Updated on 2022/10/01

写真a

 
FUNABIKI Nobuo
 
Organization
Faculty of Natural Science and Technology Professor
Position
Professor
External link

Degree

  • Doctor of Engineering ( The University of Tokyo )

Research Interests

  • 教育工学

  • Wireless Networking

  • Information and Communication Technology

  • Optimization Algorithms

  • Web Systems

  • Webシステム

  • Educational Technology

  • Wireless Networks

  • 情報通信工学

  • 最適化アルゴリズム

Research Areas

  • Humanities & Social Sciences / Educational technology

  • Informatics / Information network

  • Informatics / Theory of informatics

  • Informatics / Computer system

Education

  • ケ-スウェスタンリザ-ブ大学大学院   工学系研究科   電気工学

    - 1991

      More details

    Country: United States

    researchmap

  • Case Western Reserve University   Graduate School of Engineering   Electrical Engineering

    - 1991

      More details

  • The University of Tokyo   工学部   計数工学科

    - 1984

      More details

    Country: Japan

    researchmap

  • The University of Tokyo    

    - 1984

      More details

Research History

  • - 岡山大学大学院自然科学研究科 教授(改組による) 教授

    2005

      More details

  • - Professor,Professor, Graduate School of Natural Science and Technology, Okayama University

    2005

      More details

  • - Professor,Graduate School of Natural Science and Technology,Okayama University

    2004

      More details

  • - 岡山大学自然科学研究科 教授

    2004

      More details

  • Professor,Professor, Faculty of Engineering, Okayama University

    2001 - 2005

      More details

  • Okayama University   Faculty of Engineering

    2001 - 2005

      More details

  • Osaka University   School of Engineering Science Direct Affiliates

    1995 - 2001

      More details

  • Associate Professor,Associate Professor, Faculty of Engineering Science, Osaka University

    1995 - 2001

      More details

  • Osaka University   School of Engineering Science Direct Affiliates

    1994 - 1995

      More details

  • Senior Assistant Professor,Assistant Professor, Faculty of Engineering Science, Osaka University

    1994 - 1995

      More details

  • 住友金属工業株式会社 職員(技術系)

    1984 - 1994

      More details

  • Technical Staff,Sumitomo Metal Industries, Ltd.

    1984 - 1994

      More details

▼display all

Professional Memberships

▼display all

Committee Memberships

  • IEEE   IEEE Hiroshima Section Chairman  

    2014   

      More details

    Committee type:Academic society

    IEEE

    researchmap

  • IEEE   広島支部支部長  

    2014   

      More details

    Committee type:Academic society

    IEEE

    researchmap

 

Papers

  • Application of Fingerprint-based Indoor Localization System Using IEEE 802.15.4 to Two-Floors Environment.

    Pradini Puspitaningayu, Nobuo Funabiki, Yuan-Zhi Huo, Kazushi Hamazaki, Minoru Kuribayashi, Wen-Chung Kao

    LifeTech   239 - 240   2022

     More details

    Publishing type:Research paper (international conference proceedings)  

    DOI: 10.1109/LifeTech53646.2022.9754790

    researchmap

    Other Link: https://dblp.uni-trier.de/db/conf/lifetech/lifetech2022.html#PuspitaningayuF22

  • Implementations of Online Job Acceptance Functions in User-PC Computing System.

    Hein Htet, Nobuo Funabiki, Ariel Kamoyedji, Xudong Zhou, Yan Watequlis Syaifudin, Irin Tri Anggraini, Minoru Kuribayashi

    LifeTech   121 - 122   2022

     More details

    Publishing type:Research paper (international conference proceedings)  

    DOI: 10.1109/LifeTech53646.2022.9754807

    researchmap

    Other Link: https://dblp.uni-trier.de/db/conf/lifetech/lifetech2022.html#HtetFKZSAK22

  • A Proposal of Phrase Fill-in-blank Problem for Learning Recursive Function in C Programming.

    Xiqin Lu, Shixi Chen, Nobuo Funabiki, Minoru Kuribayashi, Kiyoshi Ueda

    LifeTech   123 - 124   2022

     More details

    Publishing type:Research paper (international conference proceedings)  

    DOI: 10.1109/LifeTech53646.2022.9754593

    researchmap

    Other Link: https://dblp.uni-trier.de/db/conf/lifetech/lifetech2022.html#LuCFKU22

  • A Proposal of the Fingerprint Optimization Method for the Fingerprint-Based Indoor Localization System with IEEE 802.15.4 Devices.

    Yuan-Zhi Huo, Pradini Puspitaningayu, Nobuo Funabiki, Kazushi Hamazaki, Minoru Kuribayashi, Kazuyuki Kojima

    Information(Inf.)   13 ( 5 )   211 - 211   2022

     More details

    Publishing type:Research paper (scientific journal)  

    DOI: 10.3390/info13050211

    researchmap

  • Feasibility investigations of access-point transmission power optimization method under co-use of channel bonding and non channel bonding in wireless local-area network Reviewed

    Fatema Akhter, Sun Yuanshuai, Nobuo Funabiki, Hendy Briantoro, Kwenga Ismael Munene, Md. Mahbubur Rahman

    The Ninth International Symposium on Computing and Networking Workshops   69 - 72   2021.11

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A proposal of dynamic job scheduling algorithm considering CPU coreutilization for User-PC computing system Reviewed

    Ariel Kamoyedji, Nobuo Funabiki, Hein Htet, Minoru Kuribayashi

    The Ninth International Symposium on Computing and Networking Workshops   268 - 271   2021.11

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A proposal of code modification problem for Web client programming using JavaScript Reviewed

    Khaing Hsu Wai, Nobuo Funabiki, Khin Thet Mon, San Hay Mar Shwe, Htoo Htoo, Sandi Kyaw, Khin Sandar Lin

    The Ninth International Symposium on Computing and Networking (CANDAR)   196 - 202   2021.11

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A study of grammar-concept understanding problems for web client programming with JavaScript Reviewed

    Khin Thet Mon, Nobuo Funabiki, Soe Thandar Aung, Khaing Hsu Wai, Khin Sandar Lin

    International Symposium on Socially and Technically Symbiotic Systems (STSS)   2021.11

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • Answer platform implementation using Node.js for code writing problem in Java programming learning assistant system Reviewed

    Soe Thandar Aung, Nobuo Funabiki, Yan Watequlis Syaifudin, Htoo Htoo, Sandi Kyaw, Wen-Chung Kao

    International Symposium on Socially and Technically Symbiotic Systems (STSS)   2021.11

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A proposal of code modification problem for Python programming learning assistant system Reviewed

    San Hay Mar Shwe, Nobuo Funabiki, Htoo Htoo, Sandi Kyaw, Khaing Hsu Wai, Wen-Chung Kao

    International Symposium on Socially and Technically Symbiotic Systems (STSS)   2021.11

     More details

    Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A proposal of grammar-concept understanding problem in Java programming learning assistant system Reviewed

    Soe Thandar Aung, Nobuo Funabiki, Yan Watequlis Syaifudin, Htoo Htoo, Sandi Kyaw, Shune Lae Aung, Nem Khan Dim, Wen-Chung Kao

    Journal of Advances in Information Technology (JAIT)   12 ( 4 )   342 - 345   2021.11

     More details

    Authorship:Corresponding author   Publishing type:Research paper (scientific journal)  

    researchmap

  • An OpenPose-based exercise and performance learning assistant design for self-practice Yoga Reviewed

    Cheng-Hsien Lin, Shih-Wei Shen, Irin Tri Anggraini, Nobuo Funabiki, Chih-Peng Fan

    IEEE 10th Global Conference on Consumer Electronics (GCCE)   533 - 534   2021.10

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • Test code improvements for code writing problem in Java programming assistant system Reviewed

    Xiqin Lu, Huiyu Qi, Nobuo Funabiki, Soe Thandar Aung, Ei Ei Htet, Khin Sandar Lin, Wen-Chung Kao

    IEEE 10th Global Conference on Consumer Electronics (GCCE)   678 - 682   2021.10

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • Applicability investigation of transmission power optimization method for concurrently communicating access-points using channel bonding and non-Bonding in WLAN Reviewed

    Fatema Akhter, Nobuo Funabiki, Hendy Briantoro, Kwenga Ismael Munene, Md. Mahbubur Rahman, Minoru Kuribayashi

    International Conference on Vocational Education and Electrical Engineering (ICVEE)   2021.10

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • An implementation of multimedia resources learning topic for interactive applications in Android programming learning assistance system Reviewed

    Yan Watequlis Syaifudin, Nobuo Funabiki, Mustika Mentari, d Muhammad, Sofiul Fuad

    International Conference on Vocational Education and Electrical Engineering (ICVEE)   2021.10

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • Investigations of detection accuracy improvements for fingerprint-based indoor localization system using IEEE 802.15.4 Reviewed

    Pradini Puspitaningayu, Yuanzhi Huo, Nobuo Funabiki, Kazushi Hamazaki, Minoru Kuribayashi, Wen-Chung Kao

    International Conference on Vocational Education and Electrical Engineering (ICVEE)   2021.10

     More details

    Publishing type:Research paper (international conference proceedings)  

    researchmap

  • Value trace problems with assisting references for Python programming self-study Reviewed

    San Hay Mar Hay Mar Shwe, Nobuo Funabiki, Yan Watequlis Syaifudin, Phyu Phyu Tar, Htoo Htoo Sandi Kyaw, Hnin Aye Thant, Wen-Chung Kao, Nandar Win Min, Thandar Myint, Ei Ei Htet

    International Journal of Web Information Systems   17 ( 4 )   287 - 299   2021.9

     More details

    Authorship:Corresponding author   Publishing type:Research paper (scientific journal)   Publisher:Emerald  

    <sec>
    <title content-type="abstract-subheading">Purpose</title>
    This study aims to present the value trace problem (VTP) for Python programming self-study, by extending the works for Java programming learning assistant system. In total, 130 VTP instances are generated using Python codes in textbooks and websites that cover basic/advanced grammar topics, fundamental data structures and algorithms and two common library usages. Besides, assisting references on Python programming topics related to the VTP instances are introduced to assist novice learners in solving them efficiently.


    </sec>
    <sec>
    <title content-type="abstract-subheading">Design/methodology/approach</title>
    PyPLAS offers the VTP to study grammar topics and library usage through code reading. A VTP instance asks a learner to trace the actual values of important variables or output messages in the given source code. The correctness of any answer is checked through string matching.


    </sec>
    <sec>
    <title content-type="abstract-subheading">Findings</title>
    The applications to 48 undergraduate students in Myanmar and Indonesia confirm the validity of the proposal in Python programming self-studies by novice learners.


    </sec>
    <sec>
    <title content-type="abstract-subheading">Originality/value</title>
    The applications to 48 undergraduate students in Myanmar and Indonesia confirm the validity of the proposal in Python programming self-studies by novice learners.


    </sec>

    DOI: 10.1108/ijwis-03-2021-0025

    researchmap

    Other Link: https://www.emerald.com/insight/content/doi/10.1108/IJWIS-03-2021-0025/full/html

  • Applications of grammar-concept understanding and value trace problems to novice students for C programming learning

    Nobuo Funabiki, Xiqin Lu, San Hay Mar Shwe, Ei Ei Htet, Kiyoshi Ueda, Wen-Chung Kao

    IEEE International Conference on Consumer Electronics - Taiwan (ICCE-TW 2021)   265 - 266   2021.9

     More details

    Authorship:Lead author, Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • Evaluations of fingerprint-based indoor positioning system using IEEE 802.15.4 Reviewed

    Pradini Puspitaningayu, Nobuo Funabiki, Kazushi Hamazaki, Minoru Kuribayashi, Wen-Chung Kao

    IEEE International Conference on Consumer Electronics - Taiwan (ICCE-TW 2021)   267 - 268   2021.9

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A web-based online platform of distribution, collection, and validation for assignments in Android programming learning assistance system Reviewed

    Yan Watequlis Syaifudin, Nobuo Funabiki, Mustika Mentari, Habibie Ed Dien, Ikhlaashul Mu'aasyiqiin, Minoru Kuribayashi, Wen-Chung Kao

    Engineering Letters   29 ( 3 )   1178 - 1193   2021.8

     More details

    Authorship:Corresponding author   Publishing type:Research paper (scientific journal)  

    researchmap

  • A Study of Throughput Drop Estimation Model for Concurrently Communicating Links Under Coexistence of Channel Bonding and Non-bonding in IEEE 802.11n WLAN Reviewed

    Kwenga Ismael Munene, Nobuo Funabiki, Hendy Briantoro, Md Mahbubur Rahman, Sujan Chandra Roy, Minoru Kuribayashi

    COMPLEX, INTELLIGENT AND SOFTWARE INTENSIVE SYSTEMS, CISIS-2021   278   700 - 714   2021.7

     More details

    Authorship:Corresponding author   Language:English   Publishing type:Research paper (international conference proceedings)   Publisher:SPRINGER INTERNATIONAL PUBLISHING AG  

    Currently, the IEEE 802.11n wireless local-area network (WLAN) has been broadly deployed world-wide for flexible and high-speed Internet access communications. Since it uses the limited number of partially overlapping channels (POCs) at 2.4 GHz band, the throughput performance is often degraded by interferences from signals of other WLANs. Thus, we have studied throughput drop estimation models for concurrently communicating multiple links under interferences, where the 40 MHz channel bonding (CB) and 20 MHz non-CB are considered separately. We have observed that the simultaneous use of CB and non-CB can improve the performance by enhancing the channel capacity while reducing the interference. In this paper, we study the throughput drop estimation model for concurrently communicating links under coexistence of CB and non-CB in IEEE 802.11n WLAN. The model accuracy is verified by comparing the estimated throughput with the measured one under various network topologies.

    DOI: 10.1007/978-3-030-79725-6_71

    Web of Science

    researchmap

  • An implementation of job migration function using CRIU and Podman in Docker-based user-PC computing system Reviewed

    Hein Htet, Nobuo Funabiki, Ariel Kamoyedji, Zhou Xudong, Minoru Kuribayashi

    International Conference on Computer and Communications Management (ICCCM 2021)   92 - 97   2021.7

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A parameter optimization method for fingerprint-based indoor localization system using IEEE 802.15.4 devices Reviewed

    Yuanzhi Huo, Pradini Puspitaningayu, Nobuo Funabiki, Kazushi Hamazaki, Minoru Kuribayashi, Kazuyuki Kojima

    International Conference on Computer Communication and the Internet (ICCCI)   136 - 140   2021.6

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A study of element fill-in-blank problems for C programming learning assistant system Reviewed

    Htoo Htoo, Sandi Kyaw, Nobuo Funabiki, Shune Lae Aung, Nem Khan Dim, Wen-Chung Kao

    International Journal of Information and Education Technology (IJIET)   11 ( 6 )   255 - 261   2021.6

     More details

    Authorship:Corresponding author   Publishing type:Research paper (scientific journal)  

    researchmap

  • A throughput drop estimation model for concurrent communications under partially overlapping channels without channel bonding and its application to channel assignment in IEEE 802.11n WLAN Reviewed

    Kwenga Ismael Munene, Nobuo Funabiki, Hendy Briantoro, Md. Mahbubur Rahman, Fatema Akhter, Minoru Kuribayashi, Wen-Chung Kao

    IEICE Transactions on Information and Systems   104 ( 5 )   585 - 596   2021.5

     More details

    Authorship:Corresponding author   Publishing type:Research paper (scientific journal)  

    researchmap

    Other Link: https://dblp.uni-trier.de/db/journals/ieicetd/ieicetd104.html#MuneneFBRAKK21

  • A Proposal of Advanced Widgets Learning Topic for Interactive Application in Android Programming Learning Assistance System Reviewed

    Yan Watequlis Syaifudin, Nobuo Funabiki, Minoru Kuribayashi, Wen-chung Kao

    SN Computer Science   2 ( 3 )   172 - 172   2021.5

     More details

    Publishing type:Research paper (scientific journal)   Publisher:Springer Science and Business Media LLC  

    DOI: 10.1007/s42979-021-00580-1

    researchmap

    Other Link: http://link.springer.com/article/10.1007/s42979-021-00580-1/fulltext.html

  • A proposal of recommendation function for element fill-in-Blank problems in java programming learning assistant system Reviewed

    Su Sandy Wint, Nobuo Funabiki

    International Journal of Web Information Systems   17 ( 2 )   140 - 152   2021.4

     More details

    Authorship:Corresponding author   Publishing type:Research paper (scientific journal)   Publisher:Emerald  

    <sec>
    <title content-type="abstract-subheading">Purpose</title>
    To advance Java programming educations, the authors have developed a Web-based Java programming learning assistant system (JPLAS). It offers the element fill-in-blank problem (EFP) for novice students to study Java grammar and basic programming skills by filling in the missing elements in a source code. An EFP instance can be generated by selecting an appropriate code, and applying the blank element selection algorithm. As it is expected to cover broad grammar topics, a number of EFP instances have been generated. This paper aims to propose a recommendation function to guide a student solving the proper EFP instances among them.


    </sec>
    <sec>
    <title content-type="abstract-subheading">Design/methodology/approach</title>
    This function considers the difficulty level of the EFP instance and the grammar topics that have been correctly answered by the student, and is implemented at the offline answering function of JPLAS using JavaScript so that students can use it even without the Internet connections.


    </sec>
    <sec>
    <title content-type="abstract-subheading">Findings</title>
    To evaluate the effectiveness of the proposal, 85 EFP instances are prepared to cover various grammar topics, and are assigned to a total of 92 students in two universities in Myanmar and Indonesia to solve them using the recommendation function. Their solution results confirmed the effectiveness of the proposal.


    </sec>
    <sec>
    <title content-type="abstract-subheading">Originality/value</title>
    The concept of the difficulty level for an EFP instance is newly defined for the proper recommendation, and the accuracy in terms of the average numbers of answer submission times among the students is verified.


    </sec>

    DOI: 10.1108/ijwis-11-2020-0070

    researchmap

    Other Link: https://www.emerald.com/insight/content/doi/10.1108/IJWIS-11-2020-0070/full/html

  • Performance investigation of unit testing in Android programming learning assistance system Reviewed

    Yan Watequlis Syaifudin, Nobuo Funabiki, Devany C. Wijaya, Ikhlaashul Mu'aasyiqiin

    IEEE 3rd Global Conference on Life Sciences and Technologies (LifeTech 2021)   157 - 161   2021.3

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A Code Completion Problem in C Programming Learning Assistant System Reviewed

    Htoo Htoo Sandi Kyaw, Ei Ei Htet, Nobuo Funabiki, Minoru Kuribayashi, Thandar Myint, Phyu Phyu Tar, Nandar Win Min, Hnin Aye Thant, Phyu Hnin Wai

    2021 9TH INTERNATIONAL CONFERENCE ON INFORMATION AND EDUCATION TECHNOLOGY (ICIET 2021)   34 - 40   2021.3

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)   Publisher:IEEE  

    C programming has been the fundamental subject to a lot of university students for studying programming languages, algorithms, and computer architecture. Currently, we are developing C programming learning assistant system (CPLAS) for its self-study by extending our works of JPLAS for Java programming. JPLAS provides the code completion problem (CCP) to offer practical programming exercises. A CCP instance asks the completion of the given source code by filling in the missing elements. The correctness of the answer is marked through string matching by comparing each answer statement with the correct one. In this paper, we present the CCP by extending our works of the element fill-in-blank problem (EFP) in CPLAS. For evaluations, we generated 10 CCP instances and assigned them to 54 undergraduate students in Myanmar and Japan. Their solution results show that the CCP instances are generally suitable for C programming study by novice students, but those on pointer need improvements for better solutions.

    DOI: 10.1109/ICIET51873.2021.9419621

    Web of Science

    researchmap

  • An implementation of multiple activities topic for learning Intent and Fragment in Android programming learning assistance system Reviewed

    Yan Watequlis Syaifudin, Nobuo Funabiki, Ikhlaashul Mu’aasyiqiin, Devany Christina Wijaya

    International Conference on Information and Education Technology (ICIET 2021)   6 - 13   2021.3

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • Blending Android programming learning assistance system into online Android programming course Reviewed

    Yan Watequlis Syaifudin, Siti Rohani, Nobuo Funabiki, Pramana Yoga Saputra

    Blending Android programming learning assistance system into online Android programming course   26 - 33   2021.3

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • An improvement of value trace problems for pointer study in C programming Reviewed

    Xiqin Lu, Nobuo Funabiki, Htoo Htoo, Sandi Kyaw, Shune Lae Aung, Nem Khan Dim

    IEEE 3rd Global Conference on Life Sciences and Technologies (LifeTech 2021)   152 - 156   2021.3

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A study of grammar-concept understanding problem for C programming learning Reviewed

    Xiqin Lu, Soe Thandar Aung, Htoo Htoo, Sandi Kyaw, Nobuo Funabiki, Shune Lae Aung, Thin Thin Soe

    IEEE 3rd Global Conference on Life Sciences and Technologies (LifeTech 2021)   162 - 165   2021.3

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A proposal of static job scheduling algorithm considering CPU core utilization for user-PC computing system Reviewed

    Ariel Kamoyedji, Nobuo Funabiki, Hein Htet, Minoru Kuribayashi

    International Conference on Information and Education Technology (ICIET 2021)   374 - 379   2021.3

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • An implementation of offline answering function for code completion problem in programming learning assistant system Reviewed

    Htoo Htoo, Sandi Kyaw, Nobuo Funabiki, Minoru Kuribayashi

    IEEE 3rd Global Conference on Life Sciences and Technologies (LifeTech 2021)   166 - 169   2021.3

     More details

    Authorship:Corresponding author   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • Joint Optimization Method of Channel Assignment and Transmission Power for Concurrently Communicating Multiple Access-Points in Wireless Local-Area Network.

    Hendy Briantoro, Nobuo Funabiki, Md. Mahbubur Rahman, Kwenga Ismael Munene, Minoru Kuribayashi, Wen-Chung Kao

    Int. J. Netw. Comput.   11 ( 2 )   251 - 266   2021

     More details

    Authorship:Corresponding author   Publishing type:Research paper (scientific journal)  

    researchmap

    Other Link: https://dblp.uni-trier.de/db/journals/ijnc/ijnc11.html#BriantoroFRMKK21

  • Immunization of Pruning Attack in DNN Watermarking Using Constant Weight Code.

    Minoru Kuribayashi, Tatsuya Yasui, Asad Malik, Nobuo Funabiki

    CoRR   abs/2107.02961   2021

     More details

    Publishing type:Research paper (scientific journal)  

    researchmap

    Other Link: https://dblp.uni-trier.de/db/journals/corr/corr2107.html#abs-2107-02961

  • An Implementation of Offline Answering Function for Code Completion Problem in PLAS.

    Htoo Htoo Sandi Kyaw, Nobuo Funabiki, Minoru Kuribayashi

    3rd IEEE Global Conference on Life Sciences and Technologies(LifeTech)   162 - 165   2021

     More details

    Publishing type:Research paper (international conference proceedings)   Publisher:IEEE  

    DOI: 10.1109/LifeTech52111.2021.9391894

    researchmap

    Other Link: https://dblp.uni-trier.de/db/conf/lifetech/lifetech2021.html#KyawFK21

  • White-Box Watermarking Scheme for Fully-Connected Layers in Fine-Tuning Model.

    Minoru Kuribayashi, Takuro Tanaka, Shunta Suzuki, Tatsuya Yasui, Nobuo Funabiki

    IH&MMSec '21: ACM Workshop on Information Hiding and Multimedia Security(IH&MMSec)   165 - 170   2021

     More details

    Publishing type:Research paper (international conference proceedings)   Publisher:ACM  

    DOI: 10.1145/3437880.3460402

    researchmap

    Other Link: https://dblp.uni-trier.de/db/conf/ih/ihmmsec2021.html#KuribayashiTSYF21

  • Feature Extraction Based on Denoising Auto Encoder for Classification of Adversarial Examples.

    Yuma Yamasaki, Minoru Kuribayashi, Nobuo Funabiki, Huy H. Nguyen, Isao Echizen

    APSIPA ASC   1815 - 1820   2021

     More details

    Publishing type:Research paper (international conference proceedings)  

    researchmap

    Other Link: https://dblp.uni-trier.de/rec/conf/apsipa/2021

  • Application of throughput drop estimation model under partially overlapping channels to channel assignment in IEEE 802.11n WLAN Reviewed

    Kwenga Ismael Munene, Nobuo Funabiki, Hendy Briantoro, Md. Mahbubur Rahman, Fatema Akhter, and Minoru Kuribayashi

    Proceedings of 2020 International Conference on Emerging Technologies for Communications (ICETC 2020)   2020.12

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A proposal of throughput allocation method for concurrently communicating two or three hosts in wireless local-area network Reviewed

    Md. Mahbubur Rahman, Nobuo Funabiki, Kwenga Ismael Munene, Hendy Briantoro, Fatema Akhter, Minoru Kuribayashi, and Md. Manowarul Islam

    Proceedings of 2020 International Conference on Emerging Technologies for Communications (ICETC 2020)   2020.12

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • An implementation of user-PC computing system using Docker container Reviewed

    Hein Htet, Nobuo Funabiki, Ariel Kamoyedji, Minoru Kuribayashi, Fatema Akhter, Wen-Chung Kao

    International Journal of Future Computer and Communication (IJFCC)   9 ( 4 )   66 - 73   2020.12

     More details

    Authorship:Corresponding author   Publishing type:Research paper (scientific journal)  

    researchmap

  • A study of value trace problems for code reading study of C programming Reviewed

    Xiqin Lu, Nobuo Funabiki, Htoo Htoo Sandi Kyaw, Shune Lae Aung, and Nem Khan Dim

    Proceedings of 11th International Workshop on Advances in Networking and Computing (WANC 2020)   445 - 459   2020.11

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • Transmission Power Optimization of Concurrently Communicating Two Access Points in Wireless Local Area Network. Reviewed

    Hendy Briantoro, Nobuo Funabiki, Minoru Kuribayashi, Kwenga Ismael Munene, Rahardhita Widyatra Sudibyo, Md. Manowarul Islam, Wen-Chung Kao

    Int. J. Mob. Comput. Multim. Commun.   11 ( 4 )   1 - 25   2020.10

     More details

    Authorship:Lead author   Publishing type:Research paper (scientific journal)  

    DOI: 10.4018/IJMCMC.2020100101

    researchmap

  • A proposal of transmission power optimization method for concurrently communicating two access-points in wireless local-area network Reviewed

    Hendy Briantoro, Nobuo Funabiki, Kwenga Ismael Munene, Rahardhita Widyatra Sudibyo, Minoru Kuribayashi, and Wen-Chung Kao

    Proceedings of 2020 IEEE International Conference on Consumer Electronics - Taiwan (ICCE-TW 2019)   2020.9

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A proposal of code amendment problem in Java programming learning assistant system Reviewed

    10 ( 10 )   751 - 756   2020.9

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    researchmap

  • A code completion problem in Java programming learning assistant system Reviewed

    Htoo Htoo Sandi Kyaw, Su Sandy Wint, Nobuo Funabiki, and Wen-Chung Kao

    IAENG International Journal of Computer Science   47 ( 3 )   350 - 359   2020.8

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    researchmap

  • A proposal of exercise and performance learning assistant system for self-practice at home Invited Reviewed

    Irin Tri Anggraini, Achmad Basuki, Nobuo Funabiki, Xiqin Lu, Chih-Peng Fan, Yu-Chung Hsu, Cheng-Hsien Lin

    Advances in Science, Technology and Engineering Systems Journal (ASTESJ)   5 ( 5 )   1196 - 1203   2020.5

     More details

    Authorship:Corresponding author   Publishing type:Research paper (scientific journal)  

    researchmap

  • A generalized TCP fairness control method for multiple-host concurrent communications in elastic WLAN system using Raspberry Pi access-point Reviewed

    Rahardhita Widyatra Sudibyo, Nobuo Funabiki, Minoru Kuribayashi, Kwenga Ismael Munene, Hendy Briantoro, Md. Manowarul Islam, Wen-Chung Kao

    International Journal of Mobile Computing and Multimedia Communications (IJMCMC)   11 ( 2 )   18 - 40   2020.4

     More details

    Authorship:Corresponding author   Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.4018/IJMCMC.2020040102

    researchmap

  • An Implementation and Evaluation of Advanced Widgets Topic for Interactive Application Stage in Android Programming Learning Assistance System Reviewed

    Yan Watequlis Syaifudin, Nobuo Funabiki, Minoru Kuribayashi

    ICIET 2020: 2020 8TH INTERNATIONAL CONFERENCE ON INFORMATION AND EDUCATION TECHNOLOGY   88 - 93   2020.3

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)   Publisher:ASSOC COMPUTING MACHINERY  

    With the growing popularity of smartphone devices, the demand for mobile application programmers has been increasing, particularly for the most popular mobile platform Android. Then, Android application programming has become one of the most important subjects that students should learn in professional schools and universities in IT departments. To assist self-studies of students, we have developed Android Programming Learning Assistance System (APLAS). To guide students to reach correct answers for given assignments, APLAS adopts the Test-Driven Development (TDD) method to validate student answers automatically using JUnit and Robolectric. The learning model for APLAS consists of four stages where each stage has several topics. In this paper, we implement Advanced Widgets as the second topic in the Interactive Application stage and evaluate it through applications to students in an IT department in Indonesia.

    DOI: 10.1145/3395245.3396198

    Web of Science

    researchmap

  • An extension of code correction problem for Java programming learning assistant system Reviewed

    Nobuo Funabiki, Masaki Yamaguchi, Minoru Kuribayashi, Htoo Htoo Sandi Kyaw, Su Sandy Wint, Soe Thandar Aung, and Wen-Chung Kao

    Proceedings of 2020 8th International Conference on Information and Education Technology (ICIET 2020)   110 - 115   2020.3

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A proposal of preprocessing stage for active access-point configuration algorithm in elastic WLAN system Reviewed

    Mousumi Saha, Nobuo Funabiki, Sumon Kumar Debnath, Wen-Chung Kao, Shigeto Tajima, and Teruo Higashino

    Proceedings of 2020 8th International Conference on Information and Education Technology (ICIET 2020)   284 - 289   2020.3

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A proposal of TCP fairness control method for multiple-host concurrent communications in wireless local-area network Reviewed

    Rahardhita Widyatra Sudibyo, Nobuo Funabiki, Kwenga Ismael Munene, Md. Manowarul Islam, and Wen-Chung Kao

    Proceedings of 2020 IEEE International Conference on Consumer Electronics (ICCE 2020)   2020.1

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • Detection of Adversarial Examples Based on Sensitivities to Noise Removal Filter.

    Akinori Higashi, Minoru Kuribayashi, Nobuo Funabiki, Huy H. Nguyen, Isao Echizen

    Asia-Pacific Signal and Information Processing Association Annual Summit and Conference(APSIPA)   1386 - 1391   2020

     More details

    Publishing type:Research paper (international conference proceedings)   Publisher:IEEE  

    researchmap

    Other Link: https://dblp.uni-trier.de/conf/apsipa/2020

  • Classification of Video Recaptured from Display Device.

    Minoru Kuribayashi, Kodai Kamakari, Kento Kawata, Nobuo Funabiki

    Asia-Pacific Signal and Information Processing Association Annual Summit and Conference(APSIPA)   1381 - 1385   2020

     More details

    Publishing type:Research paper (international conference proceedings)   Publisher:IEEE  

    researchmap

    Other Link: https://dblp.uni-trier.de/conf/apsipa/2020

  • DeepWatermark: Embedding Watermark into DNN Model.

    Minoru Kuribayashi, Takuro Tanaka, Nobuo Funabiki

    Asia-Pacific Signal and Information Processing Association Annual Summit and Conference(APSIPA)   1340 - 1346   2020

     More details

    Publishing type:Research paper (international conference proceedings)   Publisher:IEEE  

    researchmap

    Other Link: https://dblp.uni-trier.de/conf/apsipa/2020

  • A Generalization of Transmission Power Optimization Method for Concurrently Communicating Multiple Access-Points in Wireless Local-Area Network. Reviewed

    Hendy Briantoro, Nobuo Funabiki, Kwenga Ismael Munene, Md. Mahbubur Rahman, Fatema Akhter, Wen-Chung Kao, Minoru Kuribayashi

    Eighth International Symposium on Computing and Networking Workshops   1 - 7   2020

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)   Publisher:IEEE  

    DOI: 10.1109/CANDARW51189.2020.00015

    researchmap

    Other Link: https://dblp.uni-trier.de/db/conf/ic-nc/candar2020w.html#BriantoroFMRAKK20

  • A Proposal of Air-Conditioning Guidance System Using Discomfort Index. Reviewed

    Samsul Huda, Nobuo Funabiki, Minoru Kuribayashi, Rahardhita Widyatra Sudibyo, Nobuya Ishihara, Wen-Chun Kao

    Advances on Broad-Band Wireless Computing, Communication and Applications - Proceedings of the 15th International Conference on Broad-Band and Wireless Computing, Communication and Applications (BWCCA-2020)(BWCCA)   154 - 165   2020

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)   Publisher:Springer  

    DOI: 10.1007/978-3-030-61108-8_15

    researchmap

    Other Link: https://dblp.uni-trier.de/db/conf/bwcca/bwcca2020.html#HudaFKSIK20

  • Near-Optimal Detection for Binary Tardos Code by Estimating Collusion Strategy Reviewed

    Tatsuya Yasui, Minoru Kuribayashi, Nobuo Funabiki, Isao Echizen

    IEEE Transactions on Information Forensics and Security   15   2069 - 2080   2020

     More details

    Publishing type:Research paper (scientific journal)   Publisher:Institute of Electrical and Electronics Engineers ({IEEE})  

    DOI: 10.1109/tifs.2019.2956587

    researchmap

  • A proposal of calligraphy learning assistant system with letter portion practice function using projection mapping. Reviewed

    Samsul Huda, Nobuo Funabiki, Minoru Kuribayashi, Wen-Chung Kao

    Int. J. Web Inf. Syst.   16 ( 2 )   137 - 149   2020

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1108/IJWIS-07-2019-0032

    researchmap

  • A proposal of recommendation function for solving element fill-in-blank problem in java programming learning assistant system Reviewed

    Funabiki, N., Matsumoto, S., Wint, S.S., Kuribayashi, M., Kao, W.-C.

    Advances in Intelligent Systems and Computing   1036   247 - 257   2020

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Advances in Intelligent Systems and Computing  

    DOI: 10.1007/978-3-030-29029-0_23

    Scopus

    researchmap

  • Improvement of Bit Distribution of Binary Sequence Generated by Alternative Trace Map Function.

    Fatema Akhter, Tomoya Tatara, Yasuyuki Nogami, Takuya Kusaka, Nobuo Funabiki

    Eighth International Symposium on Computing and Networking Workshops   302 - 306   2020

     More details

    Publishing type:Research paper (international conference proceedings)   Publisher:IEEE  

    DOI: 10.1109/CANDARW51189.2020.00066

    researchmap

    Other Link: https://dblp.uni-trier.de/db/conf/ic-nc/candar2020w.html#AkhterTNKF20

  • Fill-a-pix puzzle as a SAT problem Reviewed

    Aye Myint Myat, Khine Khine Htwe, and Nobuo Funabiki

    Proceedings of The 3rd International Conference on Advanced Information Technologies (ICAIT2019)   244 - 249   2019.11

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A proposal of Yoga pose assessment method using pose detection for self-learning Reviewed

    Maybel Chan Thar, Khine Zar Ne Winn, and Nobuo Funabiki

    Proceedings of The 3rd International Conference on Advanced Information Technologies (ICAIT2019)   137 - 142   2019.11

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A proposal of entertainment and performance learning assistant system for seniors Reviewed

    Irin Tri Anggraini, Achmad Basuki, and Nobuo Funabiki

    Proceedings of 2019 International Electronics Symposium (IES)   14 - 18   2019.9

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • Performance of an accelerometer-based wireless body area network in indoor environment: a preliminary study Reviewed

    Pradini Puspitaningayu, Nobuo Funabiki, Rahardhita Widyatra Sudibyo, Hendy Briantoro, Nurhayati, and Tri Wrahatnolo

    Proceedings of International Conference on Research and Academic Community Services (ICRACOS 2019)   2019.9

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A dynamic access-point transmission power minimization method using PI feedback control in elastic WLAN system for IoT applications Reviewed

    Md. Manowarul Islam, Nobuo Funabiki, Rahardhita Widyatra Sudibyo, Kwenga Ismael Munene, Wen-Chung Kao

    8   1 - 15   2019.8

     More details

    Authorship:Corresponding author   Language:English   Publishing type:Research paper (scientific journal)  

    researchmap

  • An informative test code approach in code writing problem for three object-oriented programming concepts in Java programming learning assistant system Reviewed

    Khin Khin Zaw, Win Zaw, Nobuo Funabiki, and Wen-Chung Kao

    IAENG International Journal of Computer Science   46 ( 3 )   445 - 453   2019.8

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    researchmap

  • A network configuration optimization algorithm for wireless local-area network with three Raspberry Pi access-points under concurrent communications Reviewed

    Mousumi Saha, Nobuo Funabiki, Rahardhita Widyatra Sudibyo, Sumon Kumar Debnath, Md. Manowarul Islam, Minoru Kuribayashi, and Wen-Chung Kao

    International Journal of Future Computer and Communication (IJFCC)   8 ( 2 )   55 - 62   2019.6

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    researchmap

  • An improvement of throughput measurement minimization method for access-point transmission power minimization in wireless local-area network Reviewed

    Md. Manowarul Islam, Nobuo Funabiki, Mousumi Saha, Kwenga Ismael Munene, Rahardhita Widyatra Sudibyo, and Wen-Chung Kao

    Proceedings of 2019 IEEE International Conference on Consumer Electronics - Taiwan (ICCE-TW 2019)   2019.5

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • Web-server implementation of code completion problem for Java programming learning assistant system Reviewed

    Htoo Htoo Sandi Kyaw, Nobuo Funabiki, Nobuya Ishihara, Minoru Kuribayashi, and Wen-Chung Kao

    Proceedings of 2019 IEEE International Conference on Consumer Electronics - Taiwan (ICCE-TW 2019)   2019.5

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • A personal use vehicle anti-theft tracking system using IoT platform Reviewed

    Saw Nang Paing, May Zin Oo, Mazliza Othman, and Nobuo Funabiki

    International Journal of Computer & Software Engineering   4   2019.2

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    researchmap

  • A proposal of transmission power minimization extension in active access-point configuration algorithm for elastic wireless local-area network system Reviewed

    Md. Manowarul Islam, Nobuo Funabiki, Minoru Kuribayashi, Mousumi Saha, Kwenga Ismael Munene, Rahardhita Widyatra Sudibyo, and Wen-Chung Kao

    International Journal of Computer & Software Engineering   4   2019.2

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    researchmap

  • A proposal of Android Programming Learning Assistant System with implementation of basic application learning Reviewed

    Syaifudin, Y.W., Funabiki, N., Kuribayashi, M., Kao, W.-C.

    International Journal of Web Information Systems   16 ( 1 )   115 - 135   2019

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1108/IJWIS-08-2019-0038

    Scopus

    researchmap

  • An extension of throughput drop estimation model for three-link concurrent communications under partially overlapping channels and channel bonding in ieee 802.11n wlan Reviewed

    Munene, K.I., Funabiki, N., Islam, M.M., Kuribayashi, M., Al Mamun, M.S., Kao, W.-C.

    Advances in Science, Technology and Engineering Systems   4 ( 4 )   94 - 105   2019

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.25046/aj040411

    Scopus

    researchmap

  • A proposal of TCP fairness control method for two-host concurrent communications in elastic WLAN system using raspberry pi access-point Reviewed

    Sudibyo, R.W., Funabiki, N., Kuribayashi, M., Munene, K.I., Manowarul Islam, Md., Kao, W.-C.

    Advances in Science, Technology and Engineering Systems   4 ( 6 )   76 - 80   2019

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.25046/aj040602

    Scopus

    researchmap

  • A proposal of calligraphy learning assistant system with letter portion practice function using projection mapping Reviewed

    Huda, S., Funabiki, N., Kuribayashi, M., Kao, W.-C.

    International Journal of Web Information Systems   1 - 2   2019

     More details

    Publishing type:Research paper (scientific journal)   Publisher:IEEE  

    DOI: 10.1108/IJWIS-07-2019-0032

    Scopus

    researchmap

  • Robust and secure data hiding for PDF text document Reviewed

    Kuribayashi, M., Fukushima, T., Funabiki, N.

    IEICE Transactions on Information and Systems   102-D ( 1 )   41 - 47   2019

     More details

    Publishing type:Research paper (scientific journal)  

    DOI: 10.1587/transinf.2018MUP0003

    Scopus

    researchmap

  • Throughput measurement and estimation model for concurrent communications of multiple raspberry pi access-points in wireless local-area network Reviewed

    Saha, M., Sudibyo, R.W., Funabiki, N., Kuribayashi, M., Debnath, S.K., Kao, W.-C.

    Journal of Communications   14 ( 11 )   1009 - 1009   2019

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.12720/jcm.14.11.1009-1016

    Scopus

    researchmap

  • Decentralized tracing protocol for fingerprinting system Reviewed

    Kuribayashi, M., Funabiki, N.

    APSIPA Transactions on Signal and Information Processing   8   1595 - 1601   2019

     More details

    Publishing type:Research paper (scientific journal)   Publisher:IEEE  

    DOI: 10.1017/ATSIP.2018.28

    Scopus

    researchmap

  • An Informative Test Code Approach in Code Writing Problem for Java Collections Framework in Java Programming Learning Assistant System. Reviewed

    Ei Ei Mon, Nobuo Funabiki, Minoru Kuribayashi, Wen-Chung Kao

    JSW   14 ( 5 )   200 - 208   2019

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.17706/jsw.14.5.200-208

    researchmap

  • Enhancements of minimax access-point setup optimisation approach for IEEE 802.11 WLAN. Reviewed

    Kyaw Soe Lwin, Nobuo Funabiki, Sumon Kumar Debnath, Kwenga Ismael Munene, Rahardhita Widyatra Sudibyo, Minoru Kuribayashi, Wen-Chung Kao

    IJSSC   9 ( 1 )   47 - 59   2019

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1504/IJSSC.2019.100017

    researchmap

  • A proposal of calligraphy learning assistant system using projection mapping Reviewed

    Samsul Huda, Nobuo Funabiki, Minoru Kuribayashi, and Wen-Chung Kao

    Proceedings of The 9th International Conference on Science and Engineering 2018 (ICSE 2018)   10 - 15   2018.12

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • Error debugging problem in Java Programming learning assistant system Reviewed

    Hsu Wai Hnin, Khin Khin Zaw, and Nobuo Funabiki

    Proceedings of The 9th International Conference on Science and Engineering 2018 (ICSE 2018)   293 - 297   2018.12

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • Applications of minimax access-point setup optimization approach to IEEE802.11ac WLAN at 5GHz Reviewed

    Kyaw Soe Lwin, Zinan Wang, Nobuo Funabiki, MinoruKuribayashi, and Wen-Chung Kao

    Proceedings of The 2nd International Conference on Advanced Information Technologies (ICAIT2018)   132 - 138   2018.11

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • Estimation of Collusion Attack in Bias-based Binary Fingerprinting Code, Reviewed

    T. Yasui, M. Kuribayashi, N. Funabiki, I. Echizen

    Proc. of the AsiaPacific Signal and Information Processing Association Annual Summit and Conference (APSIPA ASC 2018), 6 pages,   2018.11

     More details

  • A throughput drop estimation model for two-link concurrent communications with partially overlapping channels in IEEE 802.11n WLAN Reviewed

    Kwenga Ismael Munene, Nobuo Funabiki, Rahardhita Widyatra Sudibyo, and Wen-Chung Kao

    Proceedings of The 7th IEEE Global Conference on Consumer Electronics (GCCE2018)   809 - 810   2018.10

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • An informative test code approach for studying three object-oriented programming concepts by code writing problem in Java programming learning assistant system Reviewed

    Khin Khin Zaw, Nobuo Funabiki, Ei Ei Mon, and Wen-Chung Kao

    Proceedings of The 7th IEEE Global Conference on Consumer Electronics (GCCE2018)   592 - 596   2018.10

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • IoT-Based vehicle anti-theft tracking system Reviewed

    Saw Nang Paing, May Zin Oo, Mazliza Othman, Nobuo Funabikio

    Proceedings of 2018 Joint International Conference on Science, Technology and Innovation, Mandalay (ICSTIM)   1 - 5   2018.10

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    researchmap

  • 最大クリーク問題に対するk-opt局所探索法の改良 Reviewed

    金原一歩, 片山謙吾, 岡野傑士, 尾崎 亮, 西原典孝, 舩曵信生

    電子情報通信学会論文誌 (A)   J101-A ( 10 )   260 - 264   2018.10

     More details

  • MIMO host location optimization in active access-point configuration algorithm for elastic WLAN system Reviewed

    Sumon Kumar Debnath, Nobuo Funabiki, Mousumi Saha, and Md. Selim Al Mamun

    International Journal of Space-Based and Situated Computing (IJSSC)   8 ( 2 )   59 - 69   2018.8

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    researchmap

  • Universal scoring function based on bias equalizer for bias-based fingerprinting codes Reviewed

    Kuribayashi, M., Funabiki, N.

    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences   E101A ( 1 )   119 - 128   2018

     More details

    Publishing type:Research paper (scientific journal)  

    DOI: 10.1587/transfun.E101.A.119

    Web of Science

    Scopus

    researchmap

  • Data hiding for text document in PDF file Reviewed

    Kuribayashi, M., Fukushima, T., Funabiki, N.

    Smart Innovation, Systems and Technologies   81   390 - 398   2018

     More details

    Publishing type:Research paper (scientific journal)   Publisher:Smart Innovation, Systems and Technologies  

    DOI: 10.1007/978-3-319-63856-0_47

    Web of Science

    Scopus

    researchmap

  • A throughput estimation model under two-link concurrent communications with partially overlapping channels and its application to channel assignment in IEEE 802.11n WLAN. Reviewed

    Kwenga Ismael Munene, Nobuo Funabiki, Minoru Kuribayashi, Rahardhita Widyatra Sudibyo, Wen-Chung Kao

    IJSSC   8 ( 3 )   123 - 137   2018

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    DOI: 10.1504/IJSSC.2018.097286

    researchmap

  • Efficient Decoding Algorithm for Cyclically Permutable Code. Reviewed

    Minoru Kuribayashi, Shodai Suma, Nobuo Funabiki

    IEEE Information Theory Workshop, ITW 2018, Guangzhou, China, November 25-29, 2018   1 - 5   2018

     More details

    Publisher:IEEE  

    DOI: 10.1109/ITW.2018.8613319

    researchmap

  • Fingerprinting for multimedia content broadcasting system Reviewed

    Kuribayashi, M., Funabiki, N.

    Journal of Information Security and Applications   41   52 - 61   2018

     More details

    Publishing type:Research paper (scientific journal)  

    DOI: 10.1016/j.jisa.2018.06.002

    Web of Science

    Scopus

    researchmap

  • Dynamic Access-Point Configuration Approach for Elastic Wireless Local-Area Network System and Its Implementation Using Raspberry Pi. Reviewed

    Md. Manowarul Islam, Nobuo Funabiki, Minoru Kuribayashi, Sumon Kumar Debnath, Kwenga Ismael Munene, Kyaw Soe Lwin, Rahardhita Widyatra Sudibyo, Md. Selim Al Mamun

    Int. J. Netw. Comput.   8 ( 2 )   254 - 281   2018

     More details

    Publishing type:Research paper (scientific journal)  

    researchmap

  • Watermarking with Fixed Decoder for Aesthetic 2D Barcode Reviewed

    Minoru Kuribayashi, Ee-Chien Chang, Nobuo Funabiki

    DIGITAL FORENSICS AND WATERMARKING, IWDW 2016   10082   379 - 392   2017

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)   Publisher:SPRINGER INTERNATIONAL PUBLISHING AG  

    An aesthetic 2D-barcode, e.g. QR code, carries a given message in the payload and yet its visual appearance resembles another given logo image. The requirement of embedding a message in a "cover" image is similar to digital watermarking but with a crucial difference that, for the aesthetic 2D-barcode, the decoder is predetermined and fixed. Hence the designs and performances of the aesthetic 2D-barcode heavily rely on the predetermined decoder. In this paper, we focus on the underlying systematic encoding function in QR code. We first formulate a framework that optimizes the visual appearance of the codeword and yet meets the coding requirement. Since finding such an optimal codeword is computationally expensive, we next propose a heuristic to search for a feasible solution, and incorporate image processing operations to enhance the visual appearance. Although our method is designed for QR code, our approach can be applied to other 2D-barcodes that employ similar coding mechanisms of error correction code.

    DOI: 10.1007/978-3-319-53465-7_28

    Web of Science

    researchmap

  • Secure data management system with traceability against internal leakage. Reviewed

    Minoru Kuribayashi, Takahiro Ueda, Nobuo Funabiki

    2017 Asia-Pacific Signal and Information Processing Association Annual Summit and Conference, APSIPA ASC 2017, Kuala Lumpur, Malaysia, December 12-15, 2017   1486 - 1494   2017

     More details

  • A Design of Radio-controlled Submarine Modification for River Water Quality Monitoring Reviewed

    Sritrusta Sukaridhoto, Dadet Pramadihanto, Taufiqurrahman, Muhammad Alif, Andrie Yuwono, Nobuo Funabiki

    2015 INTERNATIONAL SEMINAR ON INTELLIGENT TECHNOLOGY AND ITS APPLICATIONS (ISITIA)   75 - 80   2015

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)   Publisher:IEEE  

    In Indonesia, river water plays important roles in human life; for example, for transportation and economic activities of the inhabitants. However, industrial, agricultural and domestic water is discarded into rivers directly in many developing countries, since drainage systems have not been completely constructed. Water quality monitoring using radio-controlled submarine provide an opportunity to develop baseline monitoring system for river water ecosystem health indicator. We propose a design modification of radio-controlled submarine for river water quality monitoring. Our design consists of modification for navigation system by added external motor, IMU and GPS; modification of processing and control system by added micro controllers and mini pc, and modification of water sensors system.

    Web of Science

    researchmap

  • Anonymous Credential System with Efficient Proofs for Monotone Formulas on Attributes Reviewed

    Shahidatul Sadiah, Toru Nakanishi, Nobuo Funabiki

    ADVANCES IN INFORMATION AND COMPUTER SECURITY (IWSEC 2015)   9241   262 - 278   2015

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)   Publisher:SPRINGER-VERLAG BERLIN  

    An anonymous credential system allows a user to convince a service provider anonymously that he/she owns certified attributes. Previously, a system to prove AND and OR relations simultaneously by CNF formulas was proposed. To achieve a constant-size proof of the formula, this system adopts an accumulator that compresses multiple attributes into a single value. However, this system has a problem: the proof generation requires a large computational time in case of lots of OR literals in the formula. One of the example formulas consists of lots of birthdate attributes to prove age. This greatly increases the public parameters correspondent to attributes, which causes a large delay in the accumulator computation due to multiplications of lots of parameters. In this paper, we propose an anonymous credential system with constant-size proofs for monotone formulas on attributes, in order to obtain more efficiency in the proof generation. The monotone formula is a logic formula that contains any combination of AND and OR relations. Our approach to prove the monotone formula is that the accumulator is extended to be adapted to the tree expressing the monotone formula. Since the use of monotone formulas increases the expression capability of the attribute proof, the number of public parameters multiplied in the accumulator is greatly decreased, which impacts the reduction of the proof generation time.

    DOI: 10.1007/978-3-319-22425-1_16

    Web of Science

    researchmap

  • A Linux-PC Implementation Design for Elastic WLAN System Reviewed

    Md Ezharul Islam, Nobuo Funabiki

    2ND INTERNATIONAL CONFERENCE ON ELECTRICAL ENGINEERING AND INFORMATION COMMUNICATION TECHNOLOGY (ICEEICT 2015)   2015

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)   Publisher:IEEE  

    For ubiquitous network services, wireless local-area network (WLAN) systems using plural access-points (APs) are often deployed in a network field. Then, a host may detect signals from multiple APs that are interfered. This redundancy can cause performance degradations and energy wastes if a small number of hosts participates the network. On the other hand, if many hosts participate there, the number of APs should be increased so that the sufficient communication quality is provided for each host. Thus, the WLAN system is expected to be adaptive and elastic to changes of host loads. In this paper, we present an idea of the elastic WLAN system and its implementation design using Linux-PCs. The key technology for this system is the use of the AP aggregation algorithm that has been proposed to minimize the number of active APs in the field by aggregating APs using the virtual AP technology. By using Linux tools and commands, this system collects necessary information for the algorithm input, and controls the APs based on the algorithm output. The implementation and evaluation of our proposal will be in future works.

    Web of Science

    researchmap

  • An Anonymous Reputation System with Reputation Secrecy for Manager Reviewed

    Toru Nakanishi, Tomoya Nomura, Nobuo Funabiki

    INFORMATION SECURITY AND CRYPTOLOGY - ICISC 2013   8565   363 - 378   2014

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)   Publisher:SPRINGER INT PUBLISHING AG  

    In anonymous reputation systems, where after an interaction between anonymous users, one of the user evaluates the peer by giving a rating. Ratings for a user are accumulated, which becomes the reputation of the user. By using the reputation, we can know the reliability of an anonymous user. Previously, anonymous reputation systems have been proposed, using an anonymous e-cash scheme. However, in the e-cash-based systems, the bank grasps the accumulated reputations for all users, and the fluctuation of reputations. These are private information for users. Furthermore, the timing attack using the deposit times is possible, which makes the anonymity weak. In this paper, we propose an anonymous reputation system, where the reputations of users are secret for even the reputation manager such as the bank. Our approach is to adopt an anonymous credential certifying the accumulated reputation of a user. Initially a user registers with the reputation manager, and is issued an initial certificate. After each interaction with a rater, the user as the ratee obtains an updated certificate certifying the previous reputation summed up by the current rating. The update protocol is based on the zero-knowledge proofs, and thus the reputations are secret for the reputation manager. On the other hand, due to the certificate, the user cannot maliciously alter his reputation.

    DOI: 10.1007/978-3-319-12160-4_22

    Web of Science

    researchmap

  • Revocable Group Signatures with Compact Revocation List Using Accumulators Reviewed

    Toru Nakanishi, Nobuo Funabiki

    INFORMATION SECURITY AND CRYPTOLOGY - ICISC 2013   8565   435 - 451   2014

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)   Publisher:SPRINGER INT PUBLISHING AG  

    Group signatures allow a group member to anonymously sign a message on behalf of the group. One of the important issues is the revocation, and lots of revocable schemes have been proposed so far. The scheme recently proposed by Libert et al. achieves that O(1) or O(log N) efficiency except for the revocation list size (also the revocation cost), for the total number of members N and the number of revoked members R. However, since a signature is required for each subset in the used subset difference method, the size is about 900R Bytes in the 128-bit security. In the case of R = 100,000, it amounts to about 80 MB. In this paper, we extend the scheme to reduce the revocation list (also the revocation cost). In the proposed scheme, an extended accumulator accumulates T subsets, which is signed for the revocation list. The revocation list size is reduced by 1/T, although the public key size, membership certificate size and the cost of a witness computation needed for signing increase related to T.

    DOI: 10.1007/978-3-319-12160-4_26

    Web of Science

    researchmap

  • Cooking-step scheduling algorithm for simultaneous cooking of multiple dishes Reviewed

    Nobuo Funabiki, Yukiko Matsushima

    Lecture Notes in Electrical Engineering   110   123 - 136   2012

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    Nowadays, cooking everyday is hard for busy persons such as workers, students, and child-rearing families, because the time is limited on weekdays. At the same time, it is important for a healthy diet not to rely on eating-out and instant foods heavily. One solution to this situation is to cook dishes for the whole week on the weekend and eat them on the following weekdays. Then, the way of cooking with a good cooking-step schedule for multiple dishes is very important to save the time. In this chapter, we first propose a cooking model to estimate the cooking time accurately under various conditions including the kitchen layout and the number of cooks. Then, using this model, we propose a cooking-step scheduling algorithm for simultaneous cooking of multiple dishes under the cooking time constraint. Through experiments, we verify the effectiveness of our model and algorithm, where the cooking time difference between the model and the real cooking is only 2 min. © 2012 Springer Science+Business Media, LLC.

    DOI: 10.1007/978-1-4614-1695-1_10

    Scopus

    researchmap

  • A proposal of access-point aggregation approach for multiple wireless local area networks Reviewed

    Nobuo Funabiki, Md. Ezharul Islam, Toru Nakanishi, Kan Watanabe

    Proceedings - 2012 6th International Conference on Complex, Intelligent, and Software Intensive Systems, CISIS 2012   677 - 682   2012

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    With the advancement of communication technologies, multiple wireless local area networks (WLANs) have been often deployed in the same building for the Internet access services. Usually, their wireless access-points (APs) have been independently managed and operated by different groups such as departments or laboratories in a university or a company. Then, a WLAN user host can detect signals from multiple APs, which may increase the interference and the operation cost, and degrade the communication performance. As a result, the number of active APs should be minimized by aggregating the physical APs allocated in the field into limited ones by introducing virtual APs. In this paper, we define this AP aggregation problem for WLANs that aggregates the APs into the minimum number of active APs, and prove the NP-completeness of its decision problem. Then, we propose the heuristic algorithm that is composed of five phases. The effectiveness of our proposal has been verified through simulations in two instances. © 2012 Crown Copyright.

    DOI: 10.1109/CISIS.2012.121

    Scopus

    researchmap

  • An Extension of Wireless Internet-Access Mesh Network Simulator for Use of Smart Antenna. Reviewed

    Nobuo Funabiki, Shigeto Tajima, Teruo Higashino, Toru Nakanishi, Kan Watanabe

    2012 Seventh International Conference on Broadband, Wireless Computing, Communication and Applications, Victoria, BC, Canada, November 12-14, 2012   517 - 522   2012

     More details

    Publisher:IEEE  

    DOI: 10.1109/BWCCA.2012.91

    researchmap

  • Anonymous IEEE802.1X Authentication System Using Group Signatures

    Sudarsono Amang, Nakanishi Toru, Nogami Yasuyuki, Funabiki Nobuo

    Information and Media Technologies   5 ( 2 )   751 - 764   2010

     More details

    Language:English   Publisher:Information and Media Technologies Editorial Board  

    Recently, ubiquitous Internet-access services have been provided by Internet service providers (ISPs) by deploying wireless local area networks (LANs) in public spaces including stations, hotels, and coffee shops. The IEEE802.1X protocol is usually used for user authentications to allow only authorized users to access services. Then, although user personal information of access locations, services, and operations can be easily collected by ISPs and thus, their strict management has been demanded, it becomes very difficult when multiple ISPs provide roaming services by their corporations. In this paper, we present an anonymous IEEE802.1X authentication system using a group signature scheme to allow user authentication without revealing their identities. Without user identities, ISPs cannot collect personal information. As an efficient revocable group signature scheme, we adopt the verifier-local revocation (VLR) type with some modifications for use of the fast pairing computation. We show the implementation of our proposal and evaluation results where the practicality of our system is confirmed for up to 1, 000 revoked users.

    DOI: 10.11185/imt.5.751

    CiNii Article

    researchmap

  • Anonymous IEEE802.1X authentication system using group signatures Reviewed

    Amang Sudarsono, Toru Nakanishi, Yasuyuki Nogami, Nobuo Funabiki

    Journal of Information Processing   18   63 - 76   2010

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Information Processing Society of Japan  

    Recently, ubiquitous Internet-access services have been provided by Internet service providers (ISPs) by deploying wireless local area networks (LANs) in public spaces including stations, hotels, and coffee shops. The IEEE802.1X protocol is usually used for user authentications to allow only authorized users to access services. Then, although user personal information of access locations, services, and operations can be easily collected by ISPs and thus, their strict management has been demanded, it becomes very difficult when multiple ISPs provide roaming services by their corporations. In this paper, we present an anonymous IEEE802.1X authentication system using a group signature scheme to allow user authentication without revealing their identities. Without user identities, ISPs cannot collect personal information. As an efficient revocable group signature scheme, we adopt the verifier-local revocation (VLR) type with some modifications for use of the fast pairing computation. We show the implementation of our proposal and evaluation results where the practicality of our system is confirmed for up to 1,000 revoked users.

    DOI: 10.2197/ipsjjip.18.63

    Scopus

    researchmap

  • A comparative study of open source softwares for virtualization with streaming server applications Reviewed

    Sritrusta Sukaridhoto, Nobuo Funabiki, Toru Nakanishi, Dadet Pramadihanto

    Digest of Technical Papers - IEEE International Conference on Consumer Electronics   577 - 581   2009

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    Currently, several streaming servers are available to provide a variety of multimedia applications such as VoD (Videoon-Demand), IP-phone, and IP-TV. As a result, the provision of multiple streaming servers on a single machine using the virtualization technology has become important in order to save the operational/management costs while enhancing the performance and the reliability of the system. In this paper, we show the performance evaluation of two representative open source softwares for the virtualization technology, Xen and OpenVZ, in various configurations of applications on three open source streaming servers, Red5, Darwin, and VLC. Our experimental results indicate that OpenVZ provides the better performance for streaming applications with Darwin and VLC whereas Red5 can run only on Xen. ©2009 IEEE.

    DOI: 10.1109/ISCE.2009.5156885

    Scopus

    researchmap

  • A proposal of a web-page layout optimization method for multimodal browsing sizes Reviewed

    Nobuo Funabiki, Yosuke Isshiki, Megumi Isogai, Toru Nakanishi

    Digest of Technical Papers - IEEE International Conference on Consumer Electronics   894 - 898   2009

     More details

    Authorship:Lead author   Language:English   Publishing type:Research paper (international conference proceedings)  

    Recently, Web-page browsing opportunities at multimodal browsing sizes have increased due to developments of various terminals. Meanwhile, most Web pages have been designed to fit to the standard size. As a result, the screen scroll operation is necessary to access the main content at a small size, whereas the blank space becomes large at a large size. In this paper, we propose a Web-page layout optimization method for multimodal browsing sizes by focusing on the standard Web design style with the separation of the document structure description by an XHTML file and the appearance description by a CSS file. Our method automatically generates a set of CSS files fit to different sizes from the files designed for the standard size by a user. Then, it dynamically switches to the CSS file fit to the current browsing size using JavaScript. We confirm the practicality of our proposal through experiments of the Web page generation and access at various sizes. ©2009 IEEE.

    DOI: 10.1109/ISCE.2009.5156917

    Scopus

    researchmap

  • Efficient revocable group signature schemes using primes Reviewed

    Toru Nakanishi, Nobuo Funabiki

    Journal of Information Processing   16   110 - 121   2008

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Information Processing Society of Japan  

    Group signature schemes with membership revocation have been intensively researched. In this paper, we propose revocable group signature schemes with less computational costs for signing/verification than an existing scheme without the update of the signer's secret keys. The key idea is the use of a small prime number embedded in the signer's secret key. By using simple prime integer relations between the secret prime and the public product of primes for valid or invalid members, the revocation is efficiently ensured. To show the practicality, we implemented the schemes and measured the signing/verification times in a common PC (Core2 DUO 2.13 GHz). The times are all less than 0.5 seconds even for relatively large groups (10,000 members), and thus our schemes are sufficiently practical.

    DOI: 10.2197/ipsjjip.16.110

    Scopus

    researchmap

  • Efficient Revocable Group Signature Schemes Using Primes

    Nakanishi Toru, Funabiki Nobuo

    Information and Media Technologies   3 ( 4 )   768 - 779   2008

     More details

    Language:English   Publisher:Information and Media Technologies Editorial Board  

    Group signature schemes with membership revocation have been intensively researched. In this paper, we propose revocable group signature schemes with less computational costs for signing/verification than an existing scheme without the update of the signer's secret keys. The key idea is the use of a small prime number embedded in the signer's secret key. By using simple prime integer relations between the secret prime and the public product of primes for valid or invalid members, the revocation is efficiently ensured. To show the practicality, we implemented the schemes and measured the signing/verification times in a common PC (Core2 DUO 2.13GHz). The times are all less than 0.5 seconds even for relatively large groups (10, 000 members), and thus our schemes are sufficiently practical.

    DOI: 10.11185/imt.3.768

    CiNii Article

    researchmap

  • A short anonymously revocable group signature scheme from decision linear assumption Reviewed

    Toru Nakanishi, Nobuo Funabiki

    Proceedings of the 2008 ACM Symposium on Information, Computer and Communications Security, ASIACCS '08   337 - 340   2008

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    In group signature schemes, a signature is anonymous for a verifier, while only a designated Privacy Manager (PM) can identify the signer. This identification is used for tracing a dishonest anonymous signer in case of an illegal act using the signature. However, PM can violate signers' anonymity. Recently, Brickell and Li propose a novel countermeasure for the anonymous dishonest signer without PM in the setting of the direct anonymous attestation. Here, we call the generalized group signature version anonymously revocable group signature scheme. In this scheme, after an illegal act using a group signature was found, the membership of the dishonest signer can be anonymously revoked for excluding the signer without the help of any PM. However, since the Brickell-Li scheme is based on the RSA assumption and the DDH assumption, the signature is long. In this paper, we propose a short anonymously revocable group signature scheme from supersingular curves, where we adopt the decision linear (DLIN) assumption. Compared to the simple adoption of the Brickell-Li DDH-based revoking approach to supersingular curves, the length of our signature is reduced to about from 30% to 60%. Copyright 2008 ACM.

    DOI: 10.1145/1368310.1368359

    Scopus

    researchmap

  • Hierarchical Logical Topology in WDM Ring Networks with Limited ADMs Reviewed

    Tomoya Kitani, Nobuo Funabiki, Hirozumi Yamaguchi, Teruo Higashino

    Proceedings of the IFIP Networking 2008   326-337   2008

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    DOI: 10.1007/978-3-540-79549-0_28

    researchmap

  • A proposal of improved lip contour extraction method using deformable template matching and its application to dental treatment Reviewed

    Yujin Yokogawa, Nobuo Funabiki, Teruo Higashino, Masashi Oda, Yoshihide Mori

    Systems and Computers in Japan   38 ( 5 )   80 - 88   2007.5

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    Studies of facial parts have been conducted in recent years in various fields of medical science and psychology, including studies of the lip contour and location. In fact, in the treatment of cleft lip patients in oral surgery, it is desirable to extract the precise lip contour and to identify its location on the face in order to plan the plastic surgery procedure and to follow up the site after surgery. Aiming at applications to dental treatment, in this study we attempt to extend the lip contour extraction procedure based on the deformable template to the case of a template with left-right asymmetry. An algorithm is also proposed for adjusting the hue and value thresholds in order to improve extraction accuracy and reduce the burden on the user. The proposal is evaluated using sample images of normal subjects and cleft lip patients. It is shown that the shape and location of the lip can be extracted precisely and automatically by the proposed method. In connection with application to dental clinics, we present an example of a quantitative evaluation of the lip shape by using the parameters extracted by the proposed method. © 2007 Wiley Periodicals, Inc.

    DOI: 10.1002/scj.10668

    Scopus

    researchmap

  • Proposal of a hierarchical heuristic algorithm for node assignment in bidirectional manhattan street networks Reviewed

    Masataka Yonezu, Nobuo Funabiki, Tomoya Kitani, Tokumi Yokohira, Toru Nakanishi, Teruo Higashino

    Systems and Computers in Japan   38 ( 4 )   74 - 83   2007.4

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    In wavelength division multiplexing (WDM) technology, high-speed large-capacity communication is realized by transmitting multiple optical signals with different wavelengths in parallel on an optical fiber. In WDM technology, the logical topology of the network can generally be modified by changing the wavelength assignment to the transmitters and receivers. Thus it is important to develop an algorithm that derives the wavelength assignment that maximizes the transmission efficiency of the network. This paper considers a bidirectional Manhattan street network which has a regular topology, and proposes a hierarchical two-stage heuristic algorithm. In the first stage, the initial solution is derived by hierarchical region division and node assignment to the regions. In the second stage, the solution is improved by simulated annealing (SA). The proposed algorithm is evaluated by simulations of random instances and instances for which optimal solutions are already known. The effectiveness of the proposed algorithm is demonstrated through comparisons to the existing one. © 2007 Wiley Periodicals, Inc.

    DOI: 10.1002/scj.10534

    Scopus

    researchmap

  • A channel configuration problem for access-point communications in wireless mesh networks Reviewed

    Nobuo Funabiki, Toru Nakanishi, Walaa Hassan, Kanako Uemura

    2007 15TH IEEE INTERNATIONAL CONFERENCE ON NETWORKS   466 - 471   2007

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)   Publisher:IEEE  

    For a flexible and inexpensive large-scale access network to the Internet, we have studied the wireless mesh network composed of access points (APs) as wireless routers. Each AP has multihop wireless connections with the others by the wireless distribution system (WDS). In this network, communications around Internet gateways are usually very crowded and become the bottleneck of performance, because most traffic go through there for access to the Internet. To avoid this problem, the proper channel configurations of APs concerning multiple network interface cards (NICs) and their channel assignments are essential, where for the given network and traffics, the throughput should be maximized while the cost for channel configurations be minimized. In this paper, we formulate this channel configuration problem for AP communications in the wireless mesh network, and present its two-stage heuristic algorithm. The effectiveness of our approach is verified through extensive simulations.

    Web of Science

    researchmap

  • Group signature schemes with membership revocation for large groups Reviewed

    Toru Nakanishi, Nobuo Funabiki

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E89A ( 5 )   1275 - 1283   2006.5

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

    Group signature schemes with membership revocation have been intensively researched. However, signing and/or verification of some existing schemes have computational costs of O(R), where R is the number of revoked members. Existing schemes using a dynamic accumulator or a similar technique have efficient signing and verifications with O(1) complexity. However, before signing, the signer has to modify his secret key with O(N) or O(R) complexity, where N is the group size. Therefore, for larger groups, signers suffer from enormous costs. On the other hand. an efficient scheme for middle-scale groups with about 1,000 members is previously proposed, where the signer need not modify his secret key. However this scheme also suffers from heavy signing/verification costs for larger groups with more than 10,000 members. In this paper, we adapt the middle-scale scheme to larger groups ranging from 1,000 to 1.000.000 members. At the sacrifice of the group manager's slight cost, our signing/verification is sufficiently efficient.

    DOI: 10.1093/ietfec/e89-a.5.1275

    Web of Science

    researchmap

  • A short verifier-local revocation group signature scheme with backward unlinkability Reviewed

    Toru Nakanishi, Nobuo Funabiki

    ADVANCES IN INFORMATION AND COMPUTER SECURITY, PROCEEDINGS   4266   17 - 32   2006

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:SPRINGER-VERLAG BERLIN  

    Previously Verifier-Local Revocation (VLR) group signature schemes from bilinear maps were proposed. In VLR schemes, only verifiers are involved in the revocation of a member, while signers are not involved in the revocation. Thus, the schemes are suitable for mobile environments. Furthermore, the previously proposed schemes satisfy an important property, the backward unlinkability. It means that even after a member is revoked, signatures produced by the member before the revocation remain anonymous. This property is needed in case a member leaves voluntarily or in case of a stolen key. In this paper an improved scheme is proposed, where the group signatures are shorter. This is achieved using a different assumption, DLDH assumption, and improving zero-knowledge proofs in the group signatures. The length of the proposed group signatures is about 53% of that of the previous ones.

    Web of Science

    researchmap

  • An optical-drop wavelength assignment algorithm for efficient wavelength reuse under heterogeneous traffic in WDM ring networks Reviewed

    Nobuo Funabiki, Jun Kawashima, Toru Nakanishi, Kiyohiko Okayama, Teruo Higashino

    IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences   E88-A ( 5 )   1234 - 1240   2005

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Institute of Electronics, Information and Communication, Engineers, IEICE  

    The wavelength-division multiplexing (WDM) technology has been popular in communication societies for providing very large communication bands by multiple lightpaths with different wavelengths on a single optical fiber. Particularly, a double-ring optical network architecture based on the packet-over-WDM technology such as the HORNET architecture, has been extensively studied as a next generation platform for metropolitan area networks (MANs). Each node in this architecture is equipped with a wavelength-fixed optical-drop and a fast tunable transmitter so that a lightpath can be established between any pair of nodes without wavelength conversions. In this paper, we formulate the optical-drop wavelength assignment problem (ODWAP) for efficient wavelength reuse under heterogeneous traffic in this network, and prove the JVP-completeness of its decision problem. Then, we propose a simple heuristic algorithm for the basic case of ODWAP. Through extensive simulations, we demonstrate the effectiveness of our approach in reducing waiting times for packet transmissions when a small number of wavelengths are available to retain the network cost for MANs. Copyright © 2005 The Institute of Electronics, Information and Communication Engineers.

    DOI: 10.1093/ietfec/e88-a.5.1234

    Scopus

    researchmap

  • Verifier-local revocation group signature schemes with backward unlinkability from bilinear maps Reviewed

    Toru Nakanishi, Nobuo Funabiki

    Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)   3788   533 - 548   2005

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    An approach of membership revocation in group signatures is verifier-local revocation (VLR for short). In this approach, only verifiers are involved in the revocation mechanism, while signers have no involvement. Thus, since signers have no load, this approach is suitable for mobile environments. Although Boneh and Shacham recently proposed a VLR group signature scheme from bilinear maps, this scheme does not satisfy the backward unlikability. The backward unlikability means that even after a member is revoked, signatures produced by the member before the revocation remain anonymous. In this paper, we propose VLR group signature schemes with the backward unlinkability from bilinear maps. © International Association for Cryptologic Research 2005.

    DOI: 10.1007/11593447_29

    Scopus

    researchmap

  • A proposal of hierarchical chordal ring network topology for WDM networks Reviewed

    Tomoya Kitani, Nobuo Funabiki, Teruo Higashino

    Proceedings - IEEE International Conference on Networks, ICON   2   605 - 609   2004

     More details

    Language:English   Publishing type:Research paper (international conference proceedings)  

    This paper presents a hierarchical chordal ring network topology (HCRN) as a regular logical topology for multihop WDM networks. In order to minimize the traffic increase and the transmission delay through the network due to packet relays or hops on intermediate nodes in the multihop network, the network topology is hierarchically constructed in HCRN, so that more lightpaths are assigned to connections between nearby nodes than those for distant nodes, while the maximum hop between any pair of nodes is restrained. This hierarchical topology is also beneficial to reduce the number of required wavelengths through increasing their reuses by multiple lightpaths, which is important for cost-conscious metropolitan area networks. Through comparisons on the network diameter and the number of required wavelengths with the original chordal ring network topology, we show the effectiveness of our proposed HCRN. © 2004 IEEE.

    DOI: 10.1109/ICON.2004.1409241

    Scopus

    researchmap

  • A Test Sequence Generation Method for Communication Protocols Using the SAT Algorithm Reviewed

    Takanori Mori, Hirotaka Otsuka, Nobuo Funabiki, Akio Nakata, Teruo Higashino

    Systems and Computers in Japan   34 ( 11 )   20 - 29   2003.10

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    The specification for a communication protocol is generally represented by a finite-state machine, and the operation of the machine is represented by transitions among states. The device implementing such specification is called the implementation under test (IUT). It is important for the IUT that its operation should be verified for all state transitions on the finite-state machine given in the specification. This test is called the conformance testing. In such testing it is important to generate efficiently a route containing all state transitions from the initial state. This problem is called the test sequence generation problem. This paper considers the test sequence generation problem for a communication protocol and proposes an application of an algorithm for satisfiability problem (SAT) that can flexibly handle various constraints, such as the order constraint and the time constraint among multiple constraints. The proposed method is applied to the dynamic host configuration protocol (DHCP) and its effectiveness is demonstrated. © 2003 Wiley Periodicals, Inc.

    DOI: 10.1002/scj.10482

    Scopus

    researchmap

  • A neural network combined two-stage algorithm for route assignment problems with reliability satisfaction in multihop radio networks Reviewed

    T Baba, N Funabiki, S Tajima

    ELECTRONICS AND COMMUNICATIONS IN JAPAN PART III-FUNDAMENTAL ELECTRONIC SCIENCE   85 ( 6 )   63 - 73   2002

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:SCRIPTA TECHNICA-JOHN WILEY & SONS  

    The radio network is a large-scale communication network in which a large number of stations are distributed over a wide area. Each station can communicate directly by radio packets only with neighborhood stations. Packet communication between stations which cannot communicate directly is realized by passing packets through multiple stations between them. For this purpose, when a packet communication request arises, the route for the packet and the transfer timing must be chosen so that the total transfer time is minimized and the efficiency of the radio network is maximized. It should be noted that the reliability, representing the probability that the required performance is achieved, fluctuates among the stations in the network due to the differences in the time of installation, the designed performance, and communication congestion. Consequently, this paper proposes a two-stage algorithm in which the route is assigned so that its reliability is larger than the required value. The proposed algorithm is composed of the iterative reliability satisfaction extraction procedure, in which a set of path candidates satisfying the reliability condition for the given transfer request, and the greedy neural network procedure, in which the route minimizing the cost is selected from the set of path candidates. The effectiveness of the proposed algorithm is demonstrated by simulation for networks with up to 500 stations. (C) 2002 Scripta Technica.

    DOI: 10.1002/ecjc.1102

    Web of Science

    researchmap

  • A global routing technique for Wave-Steered circuits

    *Nobuo Funabiki, Amit Singh, Arindam Mukherjee, Malgorzata Marek-Sadowska

    Proc. of Euromicro Symposium on Digital Design (DSD’2001)   2001.9

     More details

  • A minimal-state processing search algorithm for satisfiability problems Reviewed

    Nobuo Funabiki, Tokumi Yokohira, Toru Nakanishi, Shigeto Tajima, Teruo Higashino

    Proceedings of the IEEE International Conference on Systems, Man and Cybernetics   4   2769 - 2774   2001

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    The satisfiability problem (SAT) is a typical NP-complete problem where a wide range of applications has been studied. Given a set of variables U and a set of clauses C, the goal of SAT is to find a truth assignment to variables in U such that every clause in C is satisfied if it exits, or to derive the infeasibility otherwise. This paper presents an approximation algorithm called a minimal-state processing search algorithm for SAT (MIPS_SAT). MIPS_SAT repeatedly transits minimal states in terms of the cost function for searching a solution through a construction stage and a refinement stage. The first stage greedily generates an initial state composed of as many satisfied clauses as possible. The second stage iteratively seeks a solution while keeping state minimality. The performance of MIPS_SAT is verified through solving DIMACS benchmark instances.

    DOI: 10.1109/ICSMC.2001.972986

    Scopus

    researchmap

  • Expanded maximum neural network algorithm for a channel assignment problem in cellular radio networks Reviewed

    Katsuyoshi Ikenaga, Yoichi Takenaka, Nobuo Funabiki

    Electronics and Communications in Japan, Part III: Fundamental Electronic Science (English translation of Denshi Tsushin Gakkai Ronbunshi)   83 ( 11 )   11 - 19   2000

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:Scripta Technica Inc  

    In this paper, we propose a neural network algorithm that uses the expanded maximum neuron model to solve the channel assignment problem of cellular radio networks, which is an NP-complete combinatorial optimization problem. The channel assignment problem demands minimizing the total interference between the assigned channels needed to satisfy all of the communication needs. The proposed expanded maximum neuron model selects multiple neurons in descending order from the neuron inputs in each neuron group. As a result, the constraints will always be satisfied for the channel assignment problem. To improve the accuracy of the solution, neuron fixing, which is a heuristic technique used in the binary neuron model, a hill-climbing term, a shaking term, and an Omega function are introduced. The effectiveness of these additions to the expanded maximum neuron model algorithm is demonstrated. Simulations of benchmark problems demonstrate the superior performance of the proposed algorithm over conventional algorithms in finding the solution.

    DOI: 10.1002/(SICI)1520-6440(200011)83:11<11::AID-ECJC2>3.0.CO;2-D

    Scopus

    researchmap

  • A neural network for one-shot scheduling problems in multicast packet switching systems Reviewed

    T Baba, N Funabiki, S Nishikawa

    ELECTRONICS AND COMMUNICATIONS IN JAPAN PART III-FUNDAMENTAL ELECTRONIC SCIENCE   83 ( 3 )   12 - 21   2000

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:SCRIPTA TECHNICA-JOHN WILEY & SONS  

    In a multicast packet switching system, multiple output ports can send out packets simultaneously by means of the packet copying function. In realizing such a switching system, the transmission pattern must be determined for successively arising transfer requests, so that the number of transmitted packets is maximized, while satisfying the constraints. This paper considers the one-shot scheduling problem formulated by Chen and colleagues, where all copies of the same packet are sent at the same time, and proposes a new solution method using a neural network. In the proposed solution method using the neural network, the binary neuron, which is suited to the digital techniques and hardware implementation, is employed together with the synchronous update scheme. In order to improve the convergence performance and the accuracy of the solution, an operational equation with an additional heuristic term and a coefficient setting procedure taking account of transfer requests are proposed. By simulations for cases of up to 1000 ports, it is shown that the proposed solution method using the neural network is better in deriving the solution than the conventional method. It is also shown that the considered problem is NP-hard. (C) 1999 Scripta Technica.

    Web of Science

    researchmap

  • A maximum neural network approach for N-Queen problems.

    Funabiki Nobuo, Takenaka Yoichi, Nishikawa Seishi

    Biological Cybernetics   (76), pp. 251-255   1997.6

     More details

  • マキシマムニューロンを用いたN-Queen問題のニューラルネットワーク解法の提案

    竹中要一, 船曳信生, 西川清史

    情報処理学会誌   第37巻10号,pp. 1788-1791   1996.10

     More details

  • A binary neural network approach for link activation problems in multihop radio networks Reviewed

    N Funabiki, S Nishikawa

    IEICE TRANSACTIONS ON COMMUNICATIONS   E79B ( 8 )   1086 - 1093   1996.8

     More details

    Language:English   Publishing type:Research paper (scientific journal)   Publisher:IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

    This paper presents a binary neural network approach for link activation problems in multihop radio networks. The goal of the NP-complete problems is to find a conflict-free link activation schedule with the minimum number of time slots for specified communication requirements. The neural network is composed of NxM binary neurons for scheduling N links in M time slots. The energy functions and the motion equations are newly defined with heuristic methods. The simulation results through 14 instances with up to 419 links show that the neural network not only surpasses the best existing neural network in terms of the convergence rate and the computation time, but also can solve large scale instances within a constant number of iteration steps.

    Web of Science

    researchmap

  • A parallel neural network computing for the maximum clique problem

    Lee Kuo Chun, Funabiki Nobuo, Cho Y. B, Takefuji Yoshiyasu

    905 - 910   1991

     More details

    Language:English  

    &lt;p&gt;A novel computational model for large-scale maximum clique problems is proposed and tested. The maximum clique problem is first formulated as an unconstrained quadratic zero-one programming and it is solved by minimizing the weight summation over the same partition in a newly constructed graph. The proposed maximum neural network has the following advantages: (1) coefficient-parameter tuning in the motion equation is not required in the maximum neural network while the conventional neural networks suffer from it; (2) the equilibrium state of the maximum neural network is clearly defined in order to terminate the algorithm, while the existing neural networks do not have the clear definition; and (3) the maximum neural network always allows the state of the system to converge to the feasible solution, while the existing neural networks cannot guarantee it. The proposed parallel algorithm for large-size problems outperforms the best known algorithms in terms of computation time with much the same solution quality where the conventional branch-and-bound method cannot be used due to the exponentially increasing computation time.&lt;/p&gt;

    researchmap

  • A maximum neural network for the max cut problem

    Lee Kuo Chun, Takefuji Yoshiyasu, Funabiki Nobuo

    379 - 384   1991

     More details

    Language:English  

    &lt;p&gt;The max cut problem, one of the NP-complete problems, was chosen to test the capability of an artificial neural network. The algorithm based on the maximum neural network was tested by 1000 randomly generated examples, including up to 300 vertex problems. The simulation result shows that the proposed parallel algorithm using the maximum neural network generates better solutions than Hsu&#039;s algorithm within one hundred iteration steps, regardless of the problem size.&lt;/p&gt;

    researchmap

  • Analog maximum neural network circuits using the switched capacitor technique

    Cho Yong Beom, Lee Kuo Chun, Takefuji Yoshiyasu, Funabiki Nobuo

    1906 - 1911   1991

     More details

    Language:English  

    &lt;p&gt;The circuit of the maximum neural network based on the switched capacitor technique is proposed. The performance of the proposed circuit was derived from SPICE simulation. The bipartite subgraph problem is solved by using the proposed circuit. The SPICE simulation result confirms the function of the network. Because the complexity of the proposed analog circuit is so small, it is possible to fabricate an optimization system in a single chip.&lt;/p&gt;

    researchmap

▼display all

Books

  • IAENG Transactions on Engineering Sciences - Special Issue for the International Association of Engineers Conferences 2016 (Volume II)

    Sio-long Ao, Len Gelman, Haeng Kon Kim, Mahyar A Amouzegar( Role: Contributor)

    World Scientific Publishing  2018.1 

     More details

  • ICTプロフェッショナル概論

    岡山大学出版会  2013 

     More details

  • グラフ理論の基礎と応用

    共立出版  2012 

     More details

  • Intelligent control and innovative computing

    Springer  2012 

     More details

  • Wireless Mesh Networks

    InTech - Open Access Publisher  2011 

     More details

  • 情報セキュリティ対策の要点-実務と理論-

    コロナ社  2005 

     More details

  • Soft computing in communications

    Springer  2004 

     More details

▼display all

MISC

  • A Study on Convergency of DNN Watermarking Without Embedding Loss Function

    聴覚研究会資料 = Proceedings of the auditory research meeting   51 ( 7 )   393 - 398   2021.11

     More details

    Language:Japanese   Publisher:日本音響学会  

    CiNii Article

    CiNii Books

    researchmap

  • A study of fingerprint parameter optimization method for indoor localization system using IEEE802.15.4 devices

    Yuanzhi Huo, Pradini Puspitaningayu, Kazushi Hamazaki, Nobuo Funabiki, Minoru Kuribayashi, Kazuyuki Kojima

    電子情報通信学会技術研究報告   LOIS2021-4   19 - 24   2021.5

     More details

    Authorship:Corresponding author   Publishing type:Research paper, summary (national, other academic conference)  

    researchmap

  • A Study of Face Detection and Its Privacy Protection in Photos Taken by Wide-Angle Surveillance Camera

    中井康貴, 栗林稔, 舩曳信生, 藤井爽平, 石原洋之

    電子情報通信学会技術研究報告(Web)   120 ( 418(EMM2020 67-79) )   2021

  • Extensions of Answer Analysis Function for Programming Learning Assistant System

    西村一輝, 岩本晃司郎, HTOO SANDI KYAW Htoo, 舩曵信生, 栗林稔

    電子情報通信学会技術研究報告(Web)   121 ( 12(LOIS2021 1-11) )   2021

  • An Extension of Indoor Localization System Using IEEE802.15.4 Protocol for Multiple Users

    濱崎和志, PUSPITANINGAYU Pradini, 舩曵信生, 栗林稔

    電子情報通信学会技術研究報告(Web)   121 ( 12(LOIS2021 1-11) )   2021

  • An Implementation of Ventilation Request Function in Air-Conditioning Guidance System

    坂上暢規, HUO Yuanzhi, 舩曵信生, 栗林稔

    電子情報通信学会技術研究報告(Web)   121 ( 12(LOIS2021 1-11) )   2021

  • A Study on Feature Extraction Suitable for Double JPEG Compression Analysis Based on Statistical Bias Observation of DCT Coefficients

    竹下大地, 栗林稔, 舩曵信生

    電子情報通信学会技術研究報告(Web)   121 ( 28(IT2021 1-14) )   2021

  • A Study of Detecting Adversarial Examples Using Sensitivities to Multiple Auto Encoders

    山崎裕真, 栗林稔, 舩曵信生, NGUYEN Huy HONG, 越前功

    電子情報通信学会技術研究報告(Web)   121 ( 28(IT2021 1-14) )   2021

  • Detection of Adversarial Examples in CNN Image Classifiers Using Features Extracted with Multiple Strengths of Filter

    東亮憲, 栗林稔, 舩曵信生, NGUYEN Huy Hong, 越前功

    電子情報通信学会技術研究報告(Web)   120 ( 418(EMM2020 67-79) )   2021

  • Poster Presentation : Evaluation on JPEG Image Compression History Analysis Using Histogram of DCT Coefficients with Different Block Size

    聴覚研究会資料 = Proceedings of the auditory research meeting   50 ( 6 )   337 - 342   2020.11

     More details

    Language:Japanese   Publisher:日本音響学会  

    CiNii Article

    CiNii Books

    researchmap

  • DM-QIM Watermarking for Fully Connected Layers of DNN Model

    映像情報メディア学会技術報告 = ITE technical report   44 ( 18 )   21 - 26   2020.9

     More details

    Language:Japanese   Publisher:映像情報メディア学会  

    CiNii Article

    CiNii Books

    researchmap

  • A Database-less Implementation for Portable Server of Java Programming Learning Assistant System

    岩本晃司郎, 舩曵信生, 石原信也, 栗林稔

    電気・情報関連学会中国支部連合大会講演論文集(CD-ROM)   71st   2020

  • DM-QIM Watermarking for Weights of Deep Neural Network

    田中拓朗, 安井達哉, 栗林稔, 舩曵信生

    電子情報通信学会技術研究報告   119 ( 463(EMM2019 102-129)(Web) )   2020

  • Study of CNN-based Analysis on Editing History of JPEG File Using Histogram of DCT Coefficients

    小浦啓太郎, 栗林稔, 舩曵信生

    電子情報通信学会技術研究報告   119 ( 463(EMM2019 102-129)(Web) )   2020

  • Detection of Illegal Movies Captured by Video Camera from Display Device

    鎌苅康大, 河田健斗, 栗林稔, 舩曵信生

    電子情報通信学会技術研究報告   119 ( 463(EMM2019 102-129)(Web) )   2020

  • A proposal of individual input data extraction method in Word document file

    LI Yuehao, 舩曵信生, 栗林稔, 石原信也

    電子情報通信学会技術研究報告   119 ( 468(ET2019 76-105)(Web) )   2020

  • DM-QIM Watermarking for Fully Connected Layers of DNN Model

    田中拓朗, 栗林稔, 舩曵信生

    電子情報通信学会技術研究報告(Web)   120 ( 151(EMM2020 29-35) )   2020

  • Detecting Adversarial Examples Based on Sensitivities to Lossy Compression Algorithms

    東亮憲, 栗林稔, 舩曵信生, NGUYEN Huy Hong, 越前功

    電子情報通信学会技術研究報告   119 ( 463(EMM2019 102-129)(Web) )   2020

  • Evaluation on JPEG Image Compression History Analysis Using Histogram of DCT Coefficients with Different Block Size

    中嶋直也, 栗林稔, 舩曵信生

    電子情報通信学会技術研究報告(Web)   120 ( 241(EA2020 21-45) )   2020

  • Extraction of Characteristic Vectors and Its Dimension Reduction for Estimating Collusion Strategy in Fingerprinting Codes

    コンピュータセキュリティシンポジウム2019論文集   ( 2019 )   982 - 989   2019.10

     More details

    Language:Japanese  

    CiNii Article

    researchmap

  • Detecting Adversarial Example Based on Changes of CNN Classification Results Caused by JPEG Compression

    コンピュータセキュリティシンポジウム2019論文集   ( 2019 )   975 - 981   2019.10

     More details

    Language:Japanese  

    CiNii Article

    researchmap

  • Analysis on Editing History of JPEG File Based on the Bias in Histogram of DCT Coefficients

    コンピュータセキュリティシンポジウム2019論文集   ( 2019 )   969 - 974   2019.10

     More details

    Language:Japanese  

    CiNii Article

    researchmap

  • Three Improvements of Code Correction Problem in Java Programming Learning Assistant System

    情報処理学会論文誌プログラミング(PRO)   12 ( 3 )   17 - 17   2019.7

     More details

    Language:Japanese  

    本グループでは,Javaプログラミング教育の高度化を狙いとして,Webを用いたJavaプログラミング学習支援システムJPLASを開発している.JPLASでは,学習者の作成した解答コードに対し,テストコードを用いたソフトウェアテストによる自動採点を行っている.その際,学習者は,テストコード中の情報(クラス,メソッド,変数の名称,アクセス修飾子,データ型など)を読み取り,解答コードに反映する必要がある.そのため,テストコードと誤りのある問題コードを与え,後者の修正を求める,コード修正問題を提案している.また,問題コード生成のために,ソースコードに誤りを施すアルゴリズムを提案している.本研究では,コード修正問題において,1)問題コードの多様化のための誤り情報の追加,2)テストコードを用いた問題コードの検証による正当性検証,3)問題コードの難易度の制御機能,の3つの改良を提案する.それらをJPLASに実装し,本学科Javaプログラミング授業での利用により,本提案の有効性を検証する.
    To enhance Java programming educations, we have developed the Web-based Java Programming Learning Assistant System (JPLAS). JPLAS automatically marks the answer code of a student through software test using the test code. Thus, a student has to extract the necessary information from the test code to implement the answer code. To help a novice student, we proposed the code correction problem in the previous study, where a source code with errors, called a problem code, is given to a student with a test code, and is requested to be corrected to pass the test. We also proposed the algorithm to generate the problem code by making errors in the source code. In this study, we propose three improvements in the code correction problem: 1) to allow additional code items for errors for variation of the problem code, 2) to verify the correctness of the problem code by testing it, and 3) to implement the problem difficulty control function. We verify the effectiveness through applications in the Java programing course in our department.

    CiNii Article

    CiNii Books

    researchmap

  • Implementations of Answering Status Visualization and Problem Recommendation Functions in Java Programming Learning Assistant System

    情報処理学会論文誌プログラミング(PRO)   12 ( 3 )   16 - 16   2019.7

     More details

    Language:Japanese  

    Javaは,可搬性,堅牢性,安全性に優れたプログラミング言語として,業務系システム,組み込みシステムなどに幅広く利用されており,そのプログラミング教育が重要である.そこで本研究室では,Webを用いたJavaプログラミング学習支援システムJPLAS(Java Programming Learning Assistant System)を開発し,授業での運用を行っている.現状のJPLASでは,教員がそれぞれの学生の問題解答状況を一覧で把握するための機能を有していない.また,全学生に同一の問題が出されており,個々の学生の学習レベルに適した問題が出題されていない.本発表では,以上の課題を解決するために,JPLASにおいて,エレメント補充問題を対象として,学生の解答状況の可視化機能,および,各学生に次に解くべき問題の推薦機能を実装する.特に後者では,これまでの学生の解答結果の分析により,各問題の難易度の算出法を提案し,各学生の解答履歴から,その学生に適した難易度の問題を次に解くべき問題として推薦する.評価として,教員に対して,解答状況可視化機能を用いたプログラミング演習を行ってもらう.また,学生に対して,問題推薦機能を用いた問題演習を行ってもらう.その後,アンケートの実施および解答結果の分析を行い,有効性を検証する.今後の課題として,問題難易度設定方法の再検討,エレメント補充問題以外の問題も対応可能な問題推薦機能への拡張があげられる.
    As a portable, solid, secure programming language, Java is used widely such as business system and embedded system, thus its programming education is important. Therefore, we have developed the Web-based Java Programming Learning Assistant System (JPLAS) and used it in the Java programming course. JPLAS has no function which teacher can follow answering status of problems for each student. Additionally, it set the same problems to all of students, thus, it doesn't set the suitable problems corresponding to learning level for each student. In this presentation, we implement the answering status visualization function for each student and the recommendation function which recommend problems each student should solve the next for element fill in blank problems in JPLAS. In particular in the latter one, according to analysis of students' answering results so far, we propose the calculation method of problem difficulty and the system recommend the suitable problem to solve the next with learning level and answering history of each student. As an evaluation, we apply the answering status visualization function to the teacher in the programming exercise. Furthermore, we inspect the effectiveness by conducting a questionnaire survey and analyzing the answering results after students solve some of problems using problem recommendation function. In the future works, revision of the way to set up the problem level of difficulty and extension of problem recommendation function to follow other type of problems are some important tips.

    CiNii Article

    CiNii Books

    researchmap

  • Cyclically Permutable codeとLDPC符号における同期回復と誤り訂正能力の比較

    須磨尚大, 栗林稔, 舩曵信生

    情報理論とその応用シンポジウム予稿集(CD-ROM)   42nd   2019

  • Estimation of Collusion Strategy for Fingerprinting Codes under Noisy Environment

    安井達哉, 栗林稔, 舩曵信生

    電子情報通信学会技術研究報告   118 ( 494(EMM2018 91-115)(Web) )   2019

  • A Study of Patch Size for Distinguishing CGs from Real Photos Using CNN

    河田健斗, 栗林稔, 舩曵信生

    電子情報通信学会技術研究報告   118 ( 494(EMM2018 91-115)(Web) )   2019

  • Implementation and Evaluation of Fingerprinting System for Preventing Internal Leakage of Sensitive Data

    聴覚研究会資料 = Proceedings of the auditory research meeting   48 ( 7 )   661 - 666   2018.11

     More details

    Language:Japanese   Publisher:日本音響学会  

    CiNii Article

    CiNii Books

    researchmap

  • Segment-Wise Watermarking Scheme for PDF Document File Considering The Applicability to Fingerprinting System

    聴覚研究会資料 = Proceedings of the auditory research meeting   48 ( 7 )   655 - 660   2018.11

     More details

    Language:Japanese   Publisher:日本音響学会  

    CiNii Article

    CiNii Books

    researchmap

  • Dynamic Estimation of Collusion Strategy for the Detection of Colluders in Fingerprinting Codes

    安井 達哉, 栗林 稔, 舩曵 信生, 越前 功

    映像情報メディア学会技術報告 = ITE technical report   42 ( 31 )   65 - 70   2018.9

     More details

    Language:Japanese   Publisher:映像情報メディア学会  

    CiNii Article

    researchmap

  • A Study on Synchronization and Error Correction for Cyclically Permutable Code

    須磨尚大, 栗林稔, 舩曵信生

    電子情報通信学会技術研究報告   118 ( 31(IT2018 1-11) )   13 - 18   2018.5

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    J-GLOBAL

    researchmap

  • A Study of Aesthetic QR Code Considering Local Characteristic of Image

    栗林稔, 村上元貴, 舩曵信生

    電子情報通信学会技術研究報告   118 ( 31(IT2018 1-11) )   19 - 24   2018.5

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    J-GLOBAL

    researchmap

  • Poster Presentation : Estimation of Collusion Strategy for Fingerprinting Codes

    安井 達哉, 栗林 稔, 舩曵 信生

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   117 ( 476 )   17 - 22   2018.3

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    researchmap

  • Poster Presentation : Analysis on History of JPEG Compression Considering the Characteristic of Quantization Table

    小浦 啓太郎, 栗林 稔, 舩曵 信生

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   117 ( 476 )   45 - 50   2018.3

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    researchmap

  • A Study of Tracing Algorithm for Fingerprinting Code Considering Erasure Symbols (マルチメディア情報ハイディング・エンリッチメント)

    栗林 稔, 舩曵 信生

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   117 ( 425 )   13 - 18   2018.1

     More details

    Language:English   Publisher:電子情報通信学会  

    CiNii Article

    researchmap

  • An Extension of Test Code Generation Support Tool Using Test Log to Java Method with Returning Value

    日下 涼太, 舩曵 信生, 栗林 稔, 石原 信也

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   117 ( 381 )   127 - 132   2018.1

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    CiNii Books

    researchmap

  • A Proposal of Code Correction Problem for Test Code Study in Java Programming Learning Assistant System

    何 賽, 舩曵 信生, 栗林 稔, 石原 信也

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   117 ( 381 )   161 - 166   2018.1

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    CiNii Books

    researchmap

  • An Introduction of Source Code Management System for Java Programming Learning Assistant System : JPLAS

    松本 慎平, 舩曵 信生, 栗林 稔, 石原 信也

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   117 ( 380 )   167 - 172   2018.1

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    researchmap

  • A test code generation method for coding standard input/output with exception handling in Java programming learning assistant system

    Ei Ei Mon, Nobuo Funabiki, Ryota Kusaka, Khin Khin Zaw, Wen-Chung Kao

    Advances in Science, Technology and Engineering Systems Journal   3 ( 1 )   30 - 37   2018

     More details

    Language:English  

    researchmap

    Other Link: https://astesj.com/v03/i01/p05/

  • A proposal of code completion problem for Java programming learning assistant system

    Htoo Htoo, Sandi Kyaw, Shwe Thinzar Aung, Hnin Aye Thant, Nobuo Funabiki

    Proceeding of The 10th International Workshop on Virtual Environment and Network-Oriented Applications (VENOA-2018)   855 - 864   2018

     More details

    Language:English  

    researchmap

  • A proposal of hardware channel bonding for IEEE802.11n wireless network using Raspberry Pi

    Rahardhita Widyatra Sudibyo, Nobuo Funabiki, Wen-Chung Kao

    Proceeding of 2018 IEEE International Conference on Consumer Electronics - Taiwan (ICCE-TW 2018)   277 - 278   2018

     More details

    Language:English  

    researchmap

  • A study of MIMO host location optimization in active access-point configuration algorithm for elastic WLAN system

    Mousumi Saha, Nobuo Funabiki, Sumon Kumar Debnath, Wen-Chung Kao

    Proceeding of 2018 IEEE International Conference on Consumer Electronics - Taiwan (ICCE-TW 2018)   275 - 276   2018

     More details

    Language:English  

    researchmap

  • A throughput estimation model for IEEE 802.11n MIMO link in wireless local-area networks

    Sumon Kumar Debnath, Mousumi Saha, Nobuo Funabiki, Wen-Chung Kao

    Proceedings of 3rd International Conference on Computer and Communication Systems (ICCCS-2018)   327 - 331   2018

     More details

    Language:English  

    researchmap

  • A holding access-point assignment algorithm for IEEE802.11 wireless local-area networks

    Shigeto Tajima, Nobuo Funabiki, Teruo Higashino

    International Journal of Space-Based and Situated Computing   8 ( 1 )   50 - 58   2018

     More details

    Language:English  

    researchmap

  • An improved informative test code approach for code writing problem in Java programming learning assistant system

    Nobuo Funabiki, Khin Khin Zaw, Ei Ei Mon, Wen-Chung Kao

    Proceeding of The 6th International Conference on Emerging Internet, Data and Web Technologies (EIDWT-2018)   687 - 698   2018

     More details

    Authorship:Lead author   Language:English  

    researchmap

  • Dynamic Estimation of Collusion Strategy for the Detection of Colluders in Fingerprinting Codes

    安井達哉, 栗林稔, 舩曵信生, 越前功

    電子情報通信学会技術研究報告   118 ( 223(IE2018 30-43)(Web) )   2018

  • Implementation and Evaluation of Fingerprinting System for Preventing Internal Leakage of Sensitive Data

    上田貴大, 栗林稔, 舩曵信生

    電子情報通信学会技術研究報告   118 ( 312(EA2018 63-80) )   2018

  • Segment-Wise Watermarking Scheme for PDF Document File Considering The Applicability to Fingerprinting System

    福島拓哉, 栗林稔, 舩曵信生

    電子情報通信学会技術研究報告   118 ( 312(EA2018 63-80) )   2018

  • File access extension of test code generation tool for Java programming learning assistant system

    Nobuo Funabiki, Ryota Kusaka, Nobuya Ishihara, Wen-Chung Kao

    2017 IEEE 6th Global Conference on Consumer Electronics, GCCE 2017   2017-   1 - 2   2017.12

     More details

    Authorship:Lead author   Language:English   Publisher:Institute of Electrical and Electronics Engineers Inc.  

    To advance Java programming studies, we have developed the Java Programming Learning Assistant System (JPLAS). The test code plays a critical role in verifying the correctness of the source code from a student automatically at the server in the code writing problem in JPLAS. Previously, we proposed the test code generation tool that automatically generates the test code from the given source code containing standard inputs/outputs that novice students are expected to study in advance. In this paper, we extend this tool to handle the source code with file inputs/outputs. By applying the extended tool to three codes containing file inputs/outputs, the correctness of the generated test codes is confirmed.

    DOI: 10.1109/GCCE.2017.8229400

    Scopus

    researchmap

  • A holding access-point assignment algorithm for wireless local-area networks

    Shigeto Tajima, Nobuo Funabiki, Sumon Kumar Debnath, Teruo Higashino

    2017 9th IEEE International Conference on Communication Software and Networks, ICCSN 2017   2017-   367 - 371   2017.12

     More details

    Language:English   Publisher:Institute of Electrical and Electronics Engineers Inc.  

    Nowadays, various types of access-points (APs) and hosts such as dedicated APs, laptop personal computers, and mobile terminals have been used in IEEE802.11 wireless local-area networks (WLANs). As a result, the optimal assignment of holding APs into the network field depending on the host type distribution has become very important to improve the network performance. In this paper, we formulate this holding access-point assignment problem as a combinatorial optimization problem and propose its heuristic algorithm. Because plural non-overlapping channels are available in IEEE802.11 WLANs, we extend the algorithm to finding the channel assignment to the APs such that the total interference among them is minimized. The effectiveness of our proposal is verified through simulations in three instances.

    DOI: 10.1109/ICCSN.2017.8230137

    Scopus

    researchmap

  • Accumulator for monotone formulas and its application to anonymous credential system

    Shahidatul Sadiah, Toru Nakanishi, Nasima Begum, Nobuo Funabiki

    Journal of Information Processing   25   949 - 961   2017.12

     More details

    Authorship:Lead author   Language:English   Publisher:Information Processing Society of Japan  

    An anonymous credential system allows a user to convince a service provider anonymously that he/she owns certified attributes. Previously, a system to prove AND and OR relations simultaneously by CNF formulas was proposed. To achieve a constant-size proof of the formula, this system adopts an accumulator that compresses multiple attributes into a single value. However, this system has a problem: the proof generation requires a large amount of computational time in the case of lots of OR literals in the formula. Therefore, we convert the attribute relation from the CNF formula to a monotone formula to decrease the number of OR literals. The monotone formula is a logic formula that contains any combination of AND and OR relations. In this paper, we propose an extended accumulator to prove the monotone formula, and apply it to the anonymous credential system. Our approach to prove the monotone formula is that the tag assignment in the accumulator is extended to be adapted to the tree expressing the monotone formula. Using this type of formula, the number of public parameters multiplied in the accumulator is decreased, which greatly impacts the reduction of authentication time.

    DOI: 10.2197/ipsjjip.25.949

    Scopus

    researchmap

  • A Study of Throughput Estimation Model and Channel Assignment Algorithm for Partially Overlapping Channels in IEEE 802.11n Wireless Local-Area Networks (ネットワークシステム)

    イスマエル・ムネネ クエンガ, 舩曵 信生, セリム・アル・マムン ムハマド, ソウ・ルイン キョウ, クマル・デブナ シュモン

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   117 ( 303 )   23 - 28   2017.11

     More details

    Language:English   Publisher:電子情報通信学会  

    CiNii Article

    CiNii Books

    researchmap

  • A Study of Throughput Estimation Model for IEEE 802.11n MIMO Link in Wireless Local-Area Network (ネットワークシステム) Reviewed

    クマル・デブナ シュモン, 舩曵 信生, ソウ・ルイン キョウ, セリム・アル・マムン ムハマド

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   117 ( 303 )   17 - 22   2017.11

     More details

    Language:English   Publisher:電子情報通信学会  

    CiNii Article

    CiNii Books

    researchmap

  • A Study of DCT-OFDM-Based Watermarking Scheme Assisted by Error Correcting Code

    重本章吾, 栗林稔, 舩曵信生

    電子情報通信学会技術研究報告   117 ( 282(EMM2017 55-65) )   47 - 52   2017.11

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    J-GLOBAL

    researchmap

  • A study of obfuscation for the security enhancement of watermarking schemes

    山下晃一郎, 栗林稔, 舩曵信生

    電子情報通信学会技術研究報告   117 ( 282(EMM2017 55-65) )   53 - 58   2017.11

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    J-GLOBAL

    researchmap

  • Making of Code Clone Elimination Problem Function for Java Programming Learning Assistant System

    石原 信也, 舩曵 信生, 栗林 稔

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   117 ( 249 )   25 - 30   2017.10

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    CiNii Books

    researchmap

  • An Informative Test Code Approach for Code Writing Problem in Java Programming Learning Assistant System (ソフトウェアサイエンス)

    キン ゾウ キン, 舩曵 信生

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   117 ( 248 )   31 - 36   2017.10

     More details

    Language:English   Publisher:電子情報通信学会  

    CiNii Article

    CiNii Books

    researchmap

  • An Informative Test Code Approach for Code Writing Problem in Java Programming Learning Assistant System (ディペンダブルコンピューティング)

    キン ゾウ キン, 舩曵 信生

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   117 ( 249 )   31 - 36   2017.10

     More details

    Language:English   Publisher:電子情報通信学会  

    CiNii Article

    CiNii Books

    researchmap

  • A software architecture for Java programming learning assistant system

    Ishihara Nobuya, Funabiki Nobuo, Kuribayashi Minoru, Kao Wen-Chung

    International Journal of Computer & Software Engineering   2 ( 1 )   116 - 116   2017.7

     More details

    Language:English   Publisher:Graphy Publications  

    For advancements of Java programming educations, we have developed a Web-based Java Programming Learning System (JPLAS). JPLAS provides four problems with different levels, namely, element fill-inblank problem, value trace problem, statement fill-in-blank problem, and code writing problem, to cover students at different learning stages. Unfortunately, since JPLAS has been implemented by a number of students who studied in our group at different years, the code has become complex and redundant, which makes further extensions of JPLAS extremely hard. In this paper, we propose a software architecture for JPLAS to avoid redundancy. Based on the MVC model, our proposal uses Java for the model (M), HTML/CSS/JavaScript for the view (V), and JSP for the controller (C). Besides, adopting a design pattern, the marking functions of the four problems are implemented uniformly. For evaluations, after JPLAS is implemented with this architecture, the number of code files is compared with that of the previous implementation, and the number of additional files is examined for two new functions.

    CiNii Article

    researchmap

  • An offline answering function for code writing problem in Java Programming Learning Assistant System

    Nobuo Funabiki, Yingxin Wang, Nobuya Ishihara, Wen-Chung Kao

    2017 IEEE International Conference on Consumer Electronics - Taiwan, ICCE-TW 2017   241 - 242   2017.7

     More details

    Authorship:Lead author   Language:English   Publisher:Institute of Electrical and Electronics Engineers Inc.  

    In order to promote Java programming educations, the Web-based Java Programming Learning Assistant System (JPLAS) has been implemented. JPLAS provides the code writing problem, where students write Java codes that satisfy the given specifications and submit them to the JPLAS server to obtain the marks using test codes instantly. Unfortunately, JPLAS could be accessed simply when the Internet connections are available. In this study, we perform the offline answering function for the code writing problem for use of JPLAS even in places without the Internet connections. First, the teacher downloads the assignment files from the server and delivers them to the students using USB memories. Next, students solve the assignments on Eclipse including code writing and testing, then submit the results to the teacher. Finally, the teacher uploads the results to the server. To evaluate the proposed function, the questionnaire will be collected after giving five assignments to six students in our group.

    DOI: 10.1109/ICCE-China.2017.7991085

    Scopus

    researchmap

  • Watermarking Scheme with Large Capacity Considering the Internal Structure of PDF File

    福島拓哉, 栗林稔, 舩曵信生

    電子情報通信学会技術研究報告   117 ( 39(IT2017 1-15) )   13 - 18   2017.5

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    J-GLOBAL

    researchmap

  • A Proposal of Fingerprinting System for Protection of Sensitive Data from Internal Leakage

    上田貴大, 栗林稔, 舩曵信生

    電子情報通信学会技術研究報告   117 ( 39(IT2017 1-15) )   19 - 24   2017.5

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    J-GLOBAL

    researchmap

  • DCT-OFDM Watermarking Scheme Based on Communication System Model

    Minoru Kuribayashi, Shogo Shigemoto, Nobuo Funabiki

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E100A ( 4 )   944 - 952   2017.4

     More details

    Authorship:Lead author   Language:English   Publisher:IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

    In conventional spread spectrum (SS) watermarking schemes, random sequences are used for the modulation of watermark information. However, because of the mutual interference among those sequences, it requires complicated removal operation to improve the performance. In this paper, we propose an efficient spread spectrum watermarking scheme by introducing the orthogonal frequency divisiion multiplexing (OFDM) technique at the modulation of watermark information. The SS sequences in the proposed method are the DCT basic vectors modulated by a pseudo-random number (PN) sequence. We investigate the SS-based method considering the host interference at the blind detection scenario and analyze the noise caused by attacks. Because every operation is invertible, the quantization index modulation (QIM)-based method is applicable for the OFDM modulated signals. We also consider the property of watermark extracting operation in SS-based and QIM-based method and formalize their models of noisy channel in order to employ an error correcting code. The performance of their methods with error correcting code is numerically evaluated under the constraints of same distortion level in watermarked content. The experimental results indicated a criteria for the selection of SS-based and QIM-based methods for given content, which is determined by the amount of host interference. In case that the host interference is 0.8 times smaller than a watermark signal, the SS-based method is suitable. When it is 1.0 times larger, the QIM-based method should be selected.

    DOI: 10.1587/transfun.E100.A.944

    Web of Science

    researchmap

  • A Consideration of Partial Channel Interference in Channel Assignment for Holding Access-Point Assignment Problem in Wireless Local-Area Networks

    116 ( 484 )   457 - 462   2017.3

     More details

  • Cross-layer selective routing for cost and delay minimization in IEEE 802.11ac wireless mesh network

    I. W. Lai, Nobuo Funabiki, Shigeto Tajima, Md. Selim Al Mamun, Sho Fujita

    Wireless Networks   1 - 13   2017.2

     More details

    Language:English   Publisher:Springer New York LLC  

    A Wireless Internet-access Mesh NETwork (WIMNET) provides scalable and reliable internet access through the deployment of multiple access points (APs) and gateways (GWs). In this work, we propose a selective routing algorithm aiming at a hierarchical minimization of the operational cost and the maximal end-to-end delay. In particular, by deploying redundant APs/GWs in the network field, the WIMNET becomes robust to the link or AP/GW failure. However, these redundant APs/GWs increase the operational cost like the power consumption. By using Dijkstra algorithm and 2-opt algorithm, the proposed algorithm iteratively deactivates the deployed APs/GWs and performs the routing that reduces the maximal end-to-end delay based on the APs/GWs remaining active. The generated route meets the real-world constraints like fairness criterion. We further propose a cross-layer design to enhance the routing performance by exploiting the MAC-layer frame aggregation technique. The selective routing algorithm is then implemented in the WIMNET simulator proposed by our group. The numerical experiments demonstrate that in both indoor and open space environments, the proposed selective routing greatly reduces the operational cost, i.e., up to (Formula presented.) APs/GWs can be deactivated.

    DOI: 10.1007/s11276-017-1462-9

    Scopus

    researchmap

  • Cross-layer selective routing for cost and delay minimization in IEEE 802.11ac wireless mesh network

    I. W. Lai, Nobuo Funabiki, Shigeto Tajima, Md. Selim Al Mamun, Sho Fujita

    Wireless Networks   1 - 13   2017.2

     More details

    Language:English   Publisher:Springer New York LLC  

    A Wireless Internet-access Mesh NETwork (WIMNET) provides scalable and reliable internet access through the deployment of multiple access points (APs) and gateways (GWs). In this work, we propose a selective routing algorithm aiming at a hierarchical minimization of the operational cost and the maximal end-to-end delay. In particular, by deploying redundant APs/GWs in the network field, the WIMNET becomes robust to the link or AP/GW failure. However, these redundant APs/GWs increase the operational cost like the power consumption. By using Dijkstra algorithm and 2-opt algorithm, the proposed algorithm iteratively deactivates the deployed APs/GWs and performs the routing that reduces the maximal end-to-end delay based on the APs/GWs remaining active. The generated route meets the real-world constraints like fairness criterion. We further propose a cross-layer design to enhance the routing performance by exploiting the MAC-layer frame aggregation technique. The selective routing algorithm is then implemented in the WIMNET simulator proposed by our group. The numerical experiments demonstrate that in both indoor and open space environments, the proposed selective routing greatly reduces the operational cost, i.e., up to (Formula presented.) APs/GWs can be deactivated.

    DOI: 10.1007/s11276-017-1462-9

    Scopus

    researchmap

  • A Proposal of Code Clone Deletion Problem for Java Programming Learning Assistant System

    石原 信也, 舩曵 信生, 栗林 稔

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   116 ( 425 )   47 - 52   2017.1

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    researchmap

  • An Improvement of Naming Rule Testing Tool for Java Programming Learning

    松本慎平, 舩曵信生, 栗林稔, 石原信也

    電子情報通信学会技術研究報告   116 ( 426(SS2016 36-59) )   41‐46   2017.1

     More details

    Language:Japanese  

    J-GLOBAL

    researchmap

  • A Minimax Approach for Access Point Setup Optimization in IEEE 802.11n Wireless Networks

    Lwin Kyaw Soe, Funabiki Nobuo, Taniguchi Chihiro, Zaw Khin Khin, Mamun Md. Selim Al, Kuribayashi Minoru, Kao Wen-Chung

    International Journal of Networking and Computing   7 ( 2 )   187 - 207   2017

     More details

    Language:English   Publisher:IJNC Editorial Committee  

    Recently, an IEEE 802.11n access point (AP) prevailed over the wireless local area network (WLAN) due to the high-speed data transmission using the multiple input multiple output (MIMO) technology. Unfortunately, the signal propagation from the 802.11n AP is not uniform in the circumferential and height directions because of the multiple antennas for MIMO. As a result, the data transmission speed between the AP and a host could be significantly affected by their relative setup conditions. In this paper, we propose a minimax approach for optimizing the 802.11n AP setup condition in terms of the angles and the height in an indoor environment using throughput measurements. First, we detect a bottleneck host that receives the weakest signal from the AP in the field using the throughput estimation model. To explore optimal values of parameters for this model, we adopt the versatile parameter optimization tool. Then, we optimize the AP setup by changing the angles and the height while measuring throughput. For evaluations, we verify the accuracy of the model using measurement results and confirm the throughput improvements for hosts in the field by our approach.

    DOI: 10.15803/ijnc.7.2_187

    CiNii Article

    researchmap

  • A fill-in-blank problem workbook for Java programming learning assistant system

    Ta Na, Nobuo Funabiki, Khin Khin Zaw, Nobuya Ishihara, Shinpei Matsumoto, Wen-Chung Kao

    International Journal of Web Information Systems   13 ( 2 )   140 - 154   2017

     More details

    Language:English   Publisher:Emerald Group Publishing Ltd.  

    Purpose-To advance Java programming educations, the authors have developed a Java Programming Learning Assistant System (JPLAS) as a web application system. JPLAS provides fill-in-blank problems for novices to study the grammar and basic programming skills through code reading. Design/methodology/approach-To select the blank elements with grammatically correct and unique answers from a given Java code, the authors have proposed the graph-based blank element selection algorithm. Then, the code for this problem should be highly readable to encourage novice students to study it. Because code readability can be improved by proper names for identifiers, the authors have also proposed the naming rule testing algorithm to identify codes with correct names. Findings-In this paper, the authors present a fill-in-blank problem workbook by collecting suitable Java codes from textbooks and Web sites and applying these algorithms with several extensions. The workbook consists of 16 categories with a considerable number of problems that follow the conventional learning order of Java programming. Originality/value-The proper set of ready-made fill-in-blank problems is effective in enhancing the usability of JPLAS both for teachers and students. For the preliminary evaluation, the authors assign a few problems to students. In coming semesters, the authors will use this workbook in the course to verify the adequacy of the proposal for novices.

    DOI: 10.1108/IJWIS-12-2016-0076

    Scopus

    researchmap

  • A Proposal of Software Architecture for Java Programming Learning Assistant System

    Nobuya Ishihara, Nobuo Funabiki, Minoru Kuribayashi, Wen-Chung Kao

    2017 IEEE 31ST INTERNATIONAL CONFERENCE ON ADVANCED INFORMATION NETWORKING AND APPLICATIONS (AINA)   2 ( 1 )   64 - 70   2017

     More details

    Language:English   Publisher:IEEE  

    To improve Java programming educations, we have developed a Web-based Java Programming Learning System (JPLAS). To deal with students at different levels, JPLAS provides three levels of problems, namely, element fill-in-blank problems, statement fill-in-blank problems, and code writing problems. Unfortunately, since JPLAS has been implemented by various students who studied in our group at different years, the code has become complex and redundant, which makes further extensions of JPLAS extremely hard. In this paper, we propose the software architecture for JPLAS to avoid redundancy to the utmost at implementations of new functions that will be continued with this JPLAS project. Following the MVC model, our proposal basically uses Java for the model (M), JavaScript/CSS for the view (V), and JSP for the controller (C). For the evaluation, we implement JPLAS by this architecture and compare the number of code files with the previous implementation.

    DOI: 10.1109/AINA.2017.56

    Web of Science

    researchmap

    Other Link: https://www.graphyonline.com/journal/journal_article_inpress.php?journalid=IJCSE

  • A parameter optimization tool and its application to throughput estimation model for wireless LAN

    Nobuo Funabiki, Chihiro Taniguchi, Kyaw Soe Lwin, Khin Khin Zaw, Wen-Chung Kao

    The 9th International Workshop on Virtual Environment and Network-Oriented Applications (VENOA-2017)   701 - 710   2017

     More details

    Authorship:Lead author   Language:English  

    researchmap

  • A Channel Assignment Extension of Active Access-Point Configuration Algorithm for Elastic WLAN System and Its Implementation Using Raspberry Pi

    Mamun Md. Selim Al, Funabiki Nobuo, Lwin Kyaw Soe, Islam Md. Ezharul, Kao Wen-Chung

    International Journal of Networking and Computing   7 ( 2 )   248 - 270   2017

     More details

    Language:English   Publisher:IJNC Editorial Committee  

    Recently, Wireless Local-Area Network (WLAN) has become prevailing as it provides flexible Internet access to users with low cost through installation of several types of access points (APs) in the network. Previously, we proposed the active AP configuration algorithm for the elastic WLAN system using heterogeneous APs, which dynamically optimizes the configuration by activating or deactivating APs based on traffic demands. However, this algorithm assumes that any active AP may use a different channel from the other ones to avoid interferences, although the number of non-interfered channels in IEEE 802.11 protocols is limited. In this paper, we propose the extension of the AP configuration algorithm to consider the channel assignment to the active APs under this limitation. Besides, AP associations of the hosts are modified to improve the network performance by averaging loads among channels. The effectiveness of our proposal is evaluated using the WIMNET simulator in two topologies. Finally, the elastic WLAN system including this proposal is implemented using Raspberry Pi for the AP. The feasibility and performance of the implementation are verified through experiments using the testbed.

    DOI: 10.15803/ijnc.7.2_248

    CiNii Article

    researchmap

  • A Channel Assignment Extension of Active Access-Point Configuration Algorithm for Elastic WLAN System and Its Implementation Using Raspberry Pi

    Mamun Md. Selim Al, Funabiki Nobuo, Lwin Kyaw Soe, Islam Md. Ezharul, Kao Wen-Chung

    International Journal of Networking and Computing   7 ( 2 )   248 - 270   2017

     More details

    Language:English   Publisher:IJNC Editorial Committee  

    Recently, Wireless Local-Area Network (WLAN) has become prevailing as it provides flexible Internet access to users with low cost through installation of several types of access points (APs) in the network. Previously, we proposed the active AP configuration algorithm for the elastic WLAN system using heterogeneous APs, which dynamically optimizes the configuration by activating or deactivating APs based on traffic demands. However, this algorithm assumes that any active AP may use a different channel from the other ones to avoid interferences, although the number of non-interfered channels in IEEE 802.11 protocols is limited. In this paper, we propose the extension of the AP configuration algorithm to consider the channel assignment to the active APs under this limitation. Besides, AP associations of the hosts are modified to improve the network performance by averaging loads among channels. The effectiveness of our proposal is evaluated using the WIMNET simulator in two topologies. Finally, the elastic WLAN system including this proposal is implemented using Raspberry Pi for the AP. The feasibility and performance of the implementation are verified through experiments using the testbed.

    DOI: 10.15803/ijnc.7.2_248

    CiNii Article

    researchmap

  • A fill-in-blank problem workbook for Java programming learning assistant system

    Ta Na, Nobuo Funabiki, Khin Khin Zaw, Nobuya Ishihara, Shinpei Matsumoto, Wen-Chung Kao

    International Journal of Web Information Systems   13 ( 2 )   140 - 154   2017

     More details

    Language:English   Publisher:Emerald Group Publishing Ltd.  

    Purpose-To advance Java programming educations, the authors have developed a Java Programming Learning Assistant System (JPLAS) as a web application system. JPLAS provides fill-in-blank problems for novices to study the grammar and basic programming skills through code reading. Design/methodology/approach-To select the blank elements with grammatically correct and unique answers from a given Java code, the authors have proposed the graph-based blank element selection algorithm. Then, the code for this problem should be highly readable to encourage novice students to study it. Because code readability can be improved by proper names for identifiers, the authors have also proposed the naming rule testing algorithm to identify codes with correct names. Findings-In this paper, the authors present a fill-in-blank problem workbook by collecting suitable Java codes from textbooks and Web sites and applying these algorithms with several extensions. The workbook consists of 16 categories with a considerable number of problems that follow the conventional learning order of Java programming. Originality/value-The proper set of ready-made fill-in-blank problems is effective in enhancing the usability of JPLAS both for teachers and students. For the preliminary evaluation, the authors assign a few problems to students. In coming semesters, the authors will use this workbook in the course to verify the adequacy of the proposal for novices.

    DOI: 10.1108/IJWIS-12-2016-0076

    Scopus

    researchmap

  • A graph-based blank element selection algorithm for fill-in-blank problems in Java programming learning assistant system

    Nobuo Funabiki, Tana, Khin Khin Zaw, Nobuya Ishihara, Wen Chung Kao

    IAENG International Journal of Computer Science   44 ( 2 )   247 - 260   2017

     More details

    Authorship:Lead author   Language:English  

    researchmap

  • A User-PC computing system as ultralow-cost computation platform for small groups

    Nobuo Funabiki, Kyaw Soe Lwin, Yuuki Aoyagi, Minoru Kuribayashi, Wen-Chung Kao

    Application and Theory of Computer Technology   2 ( 3 )   10 - 24   2017

     More details

    Authorship:Lead author   Language:English  

    researchmap

  • A Proposal of Software Architecture for Java Programming Learning Assistant System

    Nobuya Ishihara, Nobuo Funabiki, Minoru Kuribayashi, Wen-Chung Kao

    2017 IEEE 31ST INTERNATIONAL CONFERENCE ON ADVANCED INFORMATION NETWORKING AND APPLICATIONS (AINA)   64 - 70   2017

     More details

    Language:English   Publisher:IEEE  

    To improve Java programming educations, we have developed a Web-based Java Programming Learning System (JPLAS). To deal with students at different levels, JPLAS provides three levels of problems, namely, element fill-in-blank problems, statement fill-in-blank problems, and code writing problems. Unfortunately, since JPLAS has been implemented by various students who studied in our group at different years, the code has become complex and redundant, which makes further extensions of JPLAS extremely hard. In this paper, we propose the software architecture for JPLAS to avoid redundancy to the utmost at implementations of new functions that will be continued with this JPLAS project. Following the MVC model, our proposal basically uses Java for the model (M), JavaScript/CSS for the view (V), and JSP for the controller (C). For the evaluation, we implement JPLAS by this architecture and compare the number of code files with the previous implementation.

    DOI: 10.1109/AINA.2017.56

    Web of Science

    researchmap

  • A Proposal of Test Code Generation Tool for Java Programming Learning Assistant System

    Nobuo Funabiki, Ryota Kusaka, Nobuya Ishihara, Wen-Chung Kao

    2017 IEEE 31ST INTERNATIONAL CONFERENCE ON ADVANCED INFORMATION NETWORKING AND APPLICATIONS (AINA)   51 - 56   2017

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    To advance Java programming educations, we have developed the Java programming learning assistant system (JPLAS) that can verify the correctness of the code from a student automatically using the test-driven development (TDD) method. Then, to register a new assignment in JPLAS, teachers are required to write the test code in addition to the reference source code. Unfortunately, most teachers at schools are not accustomed to writing test codes. In this paper, we propose a test code generation tool that automatically generates the test cases from the reference source code by extracting the outputs for given inputs using functions in JUnit. As assignments for Java novice students, the code that contains standard inputs/outputs is emphasized. For evaluation, we collected 97 codes containing standard inputs/outputs from Java programming text books or Web sites. The experimental result has shown that the proposed tool correctly generated the test codes for them except for one code using a random generator.

    DOI: 10.1109/AINA.2017.60

    Web of Science

    researchmap

  • A graph-based blank element selection algorithm for fill-in-blank problems in Java programming learning assistant system

    Nobuo Funabiki, Tana, Khin Khin Zaw, Nobuya Ishihara, Wen-Chung Kao

    International Journal of Computer Science   44 ( 2 )   247 - 260   2017

     More details

    Authorship:Lead author   Language:English  

    researchmap

  • An element fill-in-blank problem application in UTYCC for Java programming learning assistant system

    Htoo Htoo, Sandi Kyaw, Shwe Thinzar Aung, Hnin Aye Thant, Nobuo Funabiki

    Proceedings of The 8th International Conference on Science and Engineering 2017 (ICSE 2017)   271 - 275   2017

     More details

    Language:English  

    researchmap

  • A proposal of informative test code approach for code writing problem in Java programming learning assistant system

    Khin Khin Zaw, Nobuo Funabiki, Wen-Chung Kao

    Proceedings of The 8th International Conference on Science and Engineering 2017 (ICSE 2017)   260 - 265   2017

     More details

    Language:English  

    researchmap

  • A design-aware test code approach for code writing problem in Java programming learning assistant system

    Khin Khin Zaw, Nobuo Funabiki

    International Journal of Space-Based and Situated Computing   7 ( 3 )   145 - 154   2017

     More details

    Language:English  

    researchmap

  • Dynamic access-point configuration approach for elastic wireless local-area network system

    Md. Manowarul Islam, Md. Selim Al Mamun, Nobuo Funabiki, Minoru Kuribayashi

    Proceedings of The Fifth International Symposium on Computing and Networking (CANDAR, ASON))   2017

     More details

    Language:English  

    DOI: 10.1109/CANDAR.2017.20

    researchmap

  • A Minimax Approach for Access Point Setup Optimization in IEEE 802.11n Wireless Networks

    Lwin Kyaw Soe, Funabiki Nobuo, Taniguchi Chihiro, Zaw Khin Khin, Mamun Md. Selim Al, Kuribayashi Minoru, Kao Wen-Chung

    International Journal of Networking and Computing   7 ( 2 )   187 - 207   2017

     More details

    Language:English   Publisher:IJNC Editorial Committee  

    Recently, an IEEE 802.11n access point (AP) prevailed over the wireless local area network (WLAN) due to the high-speed data transmission using the multiple input multiple output (MIMO) technology. Unfortunately, the signal propagation from the 802.11n AP is not uniform in the circumferential and height directions because of the multiple antennas for MIMO. As a result, the data transmission speed between the AP and a host could be significantly affected by their relative setup conditions. In this paper, we propose a minimax approach for optimizing the 802.11n AP setup condition in terms of the angles and the height in an indoor environment using throughput measurements. First, we detect a bottleneck host that receives the weakest signal from the AP in the field using the throughput estimation model. To explore optimal values of parameters for this model, we adopt the versatile parameter optimization tool. Then, we optimize the AP setup by changing the angles and the height while measuring throughput. For evaluations, we verify the accuracy of the model using measurement results and confirm the throughput improvements for hosts in the field by our approach.

    DOI: 10.15803/ijnc.7.2_187

    CiNii Article

    researchmap

  • Javaプログラミング学習支援システムJPLASのステートメント補充問題のオフライン解答機能

    TANG Lewei, 舩曵信生, 石原信也, 栗林稔

    電気・情報関連学会中国支部連合大会講演論文集(CD-ROM)   68th   2017

  • A Channel Assignment Extension of Holding Access-Point Assignment Algorithm for Wireless Local-Area Networks

    116 ( 382 )   95 - 100   2016.12

     More details

  • Raspberry Pi Configuration for Access-Point and Its Throughput Measurements in IEEE802.11n Wireless Networks (ネットワークシステム)

    KUMAR DEBNATH Sumon, 舩曵 信生, SOE LWIN Kyaw, SELIM AL MAMUN Md., WIDYATRA SUDIBYO Rahardhita, HUDA Samsul

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   116 ( 382 )   101 - 106   2016.12

     More details

    Language:English   Publisher:電子情報通信学会  

    CiNii Article

    CiNii Books

    researchmap

  • A Development of Parameter Optimization Tool and Its Application to Throughput Estimation Model for Wireless LANs

    谷口知弘, 舩曵信生, 栗林稔, SOE LWIN Kyaw, SUMON KUMAR Debnath, KHIN ZAW Khin

    電子情報通信学会技術研究報告   116 ( 382(NS2016 118-140) )   89 - 94   2016.12

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    J-GLOBAL

    researchmap

  • Implementations of Problem Assignment and Offline Fill-in-blank Problem Learning Functions in Java Programming Learning Assistant System

    佐々木伸, 舩曵信生, 栗林稔, 石原信也

    電子情報通信学会技術研究報告   116 ( 351(ET2016 66-77) )   33 - 38   2016.12

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    J-GLOBAL

    researchmap

  • Offline Answering Function for Code Writing Problem in Java Programming Learning Assistant System

    WANG Yingxin, 舩曵信生, 栗林稔, 石原信也

    電子情報通信学会技術研究報告   116 ( 351(ET2016 66-77) )   39 - 44   2016.12

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    J-GLOBAL

    researchmap

  • Development of Aesthetic QR Code Encoder for Arbitrary Image

    行地将智, 栗林稔, CHANG Ee-Chien, 舩曵信生, 石原信也

    電子情報通信学会技術研究報告   116 ( 302(EA2016 48-67) )   49 - 54   2016.11

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    J-GLOBAL

    researchmap

  • Throughput Measurements for Access-Point Setup Optimization in IEEE802.11n Wireless Networks (ネットワークシステム) -- (WDN特集セッション)

    ソウ ルウィン キョウ, 舩曵 信生, キン ゾウ キン, セリム アル マムン ムハマド, 栗林 稔

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   116 ( 146 )   27 - 32   2016.7

     More details

    Language:English   Publisher:電子情報通信学会  

    CiNii Article

    researchmap

  • Throughput Measurements for Access-Point Setup Optimization in IEEE802.11n Wireless Networks (高信頼制御通信) -- (WDN特集セッション)

    ソウ ルウィン キョウ, 舩曵 信生, キン ゾウ キン, セリム アル マムン ムハマド, 栗林 稔

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   116 ( 145 )   45 - 50   2016.7

     More details

    Language:English   Publisher:電子情報通信学会  

    CiNii Article

    researchmap

  • Throughput Measurements for Access-Point Setup Optimization in IEEE802.11n Wireless Networks (無線通信システム) -- (WDN特集セッション)

    ソウ ルウィン キョウ, 舩曵 信生, キン ゾウ キン, セリム アル マムン ムハマド, 栗林 稔

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   116 ( 147 )   75 - 80   2016.7

     More details

    Language:English   Publisher:電子情報通信学会  

    CiNii Article

    CiNii Books

    researchmap

  • Considerations of Some Obfuscated Operations on the Security of Watermarking Schemes under the Kerckhoffs' Principle

    山下 晃一郎, 栗林 稔, 舩曵 信生

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   116 ( 129 )   7 - 12   2016.7

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    CiNii Books

    researchmap

  • A Study of Employment of Error Correcting Codes for the Watermarking Scheme Considering the Characteristic of Noise

    重本章吾, 栗林稔, 舩曵信生

    電子情報通信学会技術研究報告   116 ( 130(SITE2016 7-31) )   1 - 6   2016.7

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    J-GLOBAL

    researchmap

  • A Proposal of Automatic Test Code Generation Tool for Java Programming Learning Assistant System

    日下涼太, 舩曵信生, 栗林稔, 石原信也

    電子情報通信学会技術研究報告   116 ( 85(ET2016 8-20) )   41 - 46   2016.6

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    J-GLOBAL

    researchmap

  • A Proposal of Coding Rule for Java Programming Learning Assistant System Using MVC Model and Its Implementation

    石原信也, 舩曵信生, 栗林稔

    電子情報通信学会技術研究報告   116 ( 85(ET2016 8-20) )   47 - 52   2016.6

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    J-GLOBAL

    researchmap

  • A Study of Holding Access-Point Assignment Algorithm for Wireless Local-Area Networks

    116 ( 8 )   11 - 16   2016.4

     More details

  • BS-3-31 EVALUATIONS OF ACTIVE ACCESS-POINT CONFIGURATION ALGORITHM UNDER LIMITED MOBILE ROUTER ALLOCATIONS(BS-3. Advanced Networking Technologies for Innovative Information Networks)

    Mamun Md. Selim Al, Islam Md. Ezharul, Debnath Sumon Kumar, Funabiki Nobuo

    Proceedings of the IEICE General Conference   2016 ( 2 )   "S - 72"-"S-73"   2016.3

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Previously, we proposed an active access point (AP) configuration algorithm with the dynamic mobile router placement using the K-means algorithm to realize the elastic Wireless Local-Area Network (WLAN) system. However, this algorithm assumed that mobile routers can be freely placed at any location in the network, although they should be managed personally by their owners and thus, it becomes unrealistic. In this paper, we consider the locations of hosts as the candidate locations for the mobile routers, because host owners may use mobile routers for the Internet access. We compare the throughput performance of the limited mobile router locations with the previous free locations using the WIMNET simulator.

    CiNii Article

    CiNii Books

    researchmap

  • BS-3-33 PERFORMANCE EVALUATIONS OF ELASTIC WLAN SYSTEM TESTBED(BS-3. Advanced Networking Technologies for Innovative Information Networks)

    Islam Ezharul, Funabiki Nobuo, Lwin Kyaw Soe, Mamun Md. Selim Al, Debnath Sumon Kumar, Kuribayashi Minoru

    Proceedings of the IEICE General Conference   2016 ( 2 )   "S - 76"-"S-77"   2016.3

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    The elastic wireless local-area network (WLAN) system has been proposed as an adaptive and elastic WLAN system to traffic load changes in the network. Using Linux PCs, we implemented a testbed for this system that collects necessary information for the Access-Point (AP) aggregation algorithm to determine the activation/deactivation of APs by using Linux commands. Then, it controls the active APs and the associations of hosts based on the algorithm output. In this paper, we present performance evaluations of this elastic WLAN system testbed in two network scenarios in our building.

    CiNii Article

    CiNii Books

    researchmap

  • BS-3-35 THROUGHPUT MEASUREMENTS WITH VARIOUS INDOOR AP PLACEMENT CONDITIONS FOR IEEE802.11N WIRELESS NETWORKS(BS-3. Advanced Networking Technologies for Innovative Information Networks)

    Lwin Kyaw Soe, Funabiki Nobuo, Islam Md. Ezharul

    Proceedings of the IEICE General Conference   2016 ( 2 )   "S - 80"-"S-81"   2016.3

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Recently, the IEEE802.11n protocol has become popular for wireless local-area networks (WLANs). It adopts the MIMO (Multiple-Input-Multiple-Output) technology for high-speed data transmissions using multiple antennas. As a result, the device can be influenced by the installation environment in receiving/transmitting signals. This paper presents experimental performance evaluations of IEEE802.11n devices for WLAN by focusing on throughputs versus placement heights and orientations in indoor environments. Our results show that throughput performance is strongly affected by the placement heights and the orientations of access point (AP). These results should be considered in optimizing the placement of APs in the network field.

    CiNii Article

    CiNii Books

    researchmap

  • A Proposal of Readable Code Learning Tool for Java Programming

    小川卓也, 舩曵信生, 栗林稔, 石原信也, 天野憲樹

    電子情報通信学会技術研究報告   115 ( 419(MSS2015 35-66) )   35 - 40   2016.1

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    J-GLOBAL

    researchmap

  • A Proposal of Job Scheduling with Performance Measurements by Benchmarks for User PC Computing System

    青柳有輝, 舩曵信生, 栗林稔

    電子情報通信学会技術研究報告   115 ( 419(MSS2015 35-66) )   153 - 158   2016.1

     More details

    Language:Japanese   Publisher:電子情報通信学会  

    CiNii Article

    J-GLOBAL

    researchmap

  • Elastic WLAN System Model and Its Implementation on Linux-PC (システム数理と応用)

    ISLAM Md. EZHARUL, FUNABIKI Nobuo, KURIBAYASHI Minoru

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   115 ( 419 )   147 - 152   2016.1

     More details

    Language:English   Publisher:電子情報通信学会  

    CiNii Article

    researchmap

  • Elastic WLAN System Model and Its Implementation on Linux-PC (ソフトウェアサイエンス)

    ISLAM Md. EZHARUL, FUNABIKI Nobuo, KURIBAYASHI Minoru

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   115 ( 420 )   147 - 152   2016.1

     More details

    Language:English   Publisher:電子情報通信学会  

    CiNii Article

    CiNii Books

    researchmap

  • Value trace problems for graph theory algorithms in Java programming learning assistant system

    Nobuo Funabiki, Khin Khin Zaw, Minoru Kuribayashi, Wen-Chung Kao

    2016 5th International Conference on Educational and Information Technology (ICEIT 2016)   2016

     More details

    Authorship:Lead author   Language:English  

    researchmap

  • A core blank element selection algorithm for code reading studies by fill-in-blank problems in Java programming learning assistant system

    Khin Khin Zaw, Nobuo Funabiki

    The 7th International Conference on Science and Engineering 2016 (7th ICSE 2016)   204 - 208   2016

     More details

    Language:English  

    researchmap

  • Applications of coding rule learning function to workbook codes for Java programming learning assistant system

    Nobuo Funabiki, Shinpei Matsumoto, Khin Khin Zaw, Wen-Chung Kao

    The 7th International Conference on Science and Engineering 2016 (7th ICSE 2016)   1170 - 1175   2016

     More details

    Authorship:Lead author   Language:English  

    researchmap

  • A minimax approach for access-point setup optimization using throughput measurements in IEEE802.11n wireless networks

    Kyaw Soe Lwin, Nobuo Funabiki, Khin Khin Zaw, Md. Selim Al Mamun, Minoru Kuribayashi

    The Fourth International Symposium on Computing and Networking (CANDAR, ASON)   311 - 317   2016

     More details

    Language:English  

    DOI: 10.1109/CANDAR.2016.0062

    researchmap

  • A Channel Assignment Extension of Active Access-Point Configuration Algorithm for Elastic WLAN System under Limited Channels

    Md. Selim Al Mamun, Sumon Kumar Debnath, Kyaw Soe Lwin, Nobuo Funabiki

    2016 FOURTH INTERNATIONAL SYMPOSIUM ON COMPUTING AND NETWORKING (CANDAR)   318 - 324   2016

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    Previously, we proposed the active access-point (AP) configuration algorithm for elastic Wireless Local-Area Network (WLAN) systems using heterogeneous APs. This algorithm activates or deactivates APs depending on traffic demands, assuming that any active AP can use a different channel to avoid interferences among APs. However, the number of non-interfered channels in IEEE 802.11 protocols is limited. In this paper, we propose an extension of this algorithm to consider the channel assignment to the active APs under this limitation. After the channel assignment to the active APs, AP associations of hosts are improved to further minimize interferences by averaging loads among different channels. The effectiveness of our proposal is evaluated using the WIMNET simulator.

    DOI: 10.1109/CANDAR.2016.32

    Web of Science

    researchmap

  • An active access-point configuration algorithm for elastic wireless local-area network system using heterogeneous devices

    Khin Khin Zaw, Nobuo Funabiki, Wen-Chung Kao

    International Journal of Networking and Computing   6 ( 2 )   395 - 419   2016

     More details

    Language:English  

    researchmap

  • Throughput measurements for access-point installation optimization in IEEE802.11n wireless networks

    Nobuo Funabiki, Kyaw Soe Lwin, Minoru Kuribayashi, I-Wei Lai

    2016 IEEE International Conference on Consumer Electronics - Taiwan (ICCE-TW 2016)   324 - 325   2016

     More details

    Authorship:Lead author   Language:English  

    DOI: 10.1109/ICCE-TW.2016.7520994

    researchmap

  • Worker PC Performance Measurements Using Benchmarks for User-PC Computing System

    Nobuo Funabiki, Yuki Aoyagi, Minoru Kuribayashi, Wen-Chun Kao

    2016 IEEE INTERNATIONAL CONFERENCE ON CONSUMER ELECTRONICS-TAIWAN (ICCE-TW)   277 - 278   2016

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    The User-PC computing system (UPC) has been studied to provide a parallel computing platform for members in a group using idling computing resources in personal computers (PCs) of them. UPC adopts the master-worker model where we have implemented the programs for the master on Linux and for the worker on Linux and Windows. However, the current job scheduling method does not consider the real performance of a worker PC. In this paper, we implement a function to measure the performance of a worker PC using two benchmark programs. The experiment results for six PCs in our group show that there are three times difference in the CPU performance and eight times difference in the disk performance.

    DOI: 10.1109/ICCE-TW.2016.7521026

    Web of Science

    researchmap

  • Offline Answering Function for Fill-in-blank Problems in Java Programming Learning Assistant System

    Nobuo Funabiki, Hiroki Masaoka, Nobuya Ishihara, I-Wei Lai, Wen-Chung Kao

    2016 IEEE INTERNATIONAL CONFERENCE ON CONSUMER ELECTRONICS-TAIWAN (ICCE-TW)   315 - 316   2016

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    To assist Java programming educations, we have developed a Web-based Java Programming Learning Assistant System (JPLAS). JPLAS provides fill-in-blank problems to let students study the grammar and the code structure for Java by filling blank elements in a high-quality code that are composed of reserved words, identifiers, and control symbols. However, students can answer the problems only when connected with the Internet, which limits the time and place for them to use JPLAS. In this paper, we implement the offline answering function for fill-in-blank problems in JPLAS. To avoid cheating by students, we adopt the hash function and the message authentication technique. We confirm the effectiveness of our proposal through applications to the Java programming course in our department.

    DOI: 10.1109/ICCE-TW.2016.7521045

    Web of Science

    researchmap

  • Toward Personalized Learning in JPLAS: Generating and Scoring Functions for Debugging Questions

    Takato Mohri, Shingo Yamaguchi, Nobuo Funabiki

    2016 IEEE 5TH GLOBAL CONFERENCE ON CONSUMER ELECTRONICS   216 - 219   2016

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    Today, some Java program learning support systems have been proposed. Each student has his/her own learning level. It is important to give questions suitable for his/her learning level for each student. But it will cause an enormous burden to the teacher. In this paper, we implement the automatic generating function and the scoring function regarding debugging questions in Java programming learning assistant system called JPLAS. We proposed personalized learning with two functions such as automatic generating and scoring of debugging question used in JPLAS. We showed the effectiveness of proposed method with chi-squared test.

    DOI: 10.1109/GCCE.2016.7800392

    Web of Science

    researchmap

  • A Proposal of Three Extensions in Blank Element Selection Algorithm for Java Programming Learning Assistant System

    Khin Khin Zaw, Nobuo Funabiki, Minoru Kuribayashi

    2016 IEEE 5TH GLOBAL CONFERENCE ON CONSUMER ELECTRONICS   3 - 5   2016

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    To assist Java programming educations, we have developed a Web-based Java Programming Learning Assistant System (JPLAS). JPLAS provides fill-in-blank problems to let students study Java grammar and basic programming skills by filling the blanked elements in a given Java code. To generate the feasible problems, we have proposed a blank element selection algorithm using the constraint graph to select as many blanks as possible such that they have grammatically correct and unique answers. In this paper, to further increase the number of blanks and control the difficulty of the generated problem, we extend this algorithm by 1) adding operators in conditional expressions for blank candidates, 2) improving the edge generation method in the constraint graph to increase the number of blanks, and 3) introducing two parameters to change the frequency of selecting blanks. To verify the effectiveness, we apply the extended algorithm to 55 Java codes for fundamental data structure or algorithms, and confirm that these extensions can increase the number of blanks and change the problem difficulty.

    DOI: 10.1109/GCCE.2016.7800312

    Web of Science

    researchmap

  • Analysis of Fill-in-blank Problem Solution Results in Java Programming Course

    Nobuo Funabiki, Tana, Nobuya Ishihara, Wen-Chung Kao

    2016 IEEE 5TH GLOBAL CONFERENCE ON CONSUMER ELECTRONICS   479 - 480   2016

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    For advancing the educational quality of Java programming, we have proposed and implemented the Java Programming Learning Assistant System (JPLAS) as a Web application system. JPLAS offers fill-in-blank problems that request students to fill in the blank elements in a given Java code to study Java grammar and basic programming skills. In past years, we have utilized fill-in-blank problems at our Java programming courses. In this paper, we analyze solution results of students taking the course in 2015, and confirm the relatively high correlation between solution performances and course grades.

    DOI: 10.1109/GCCE.2016.7800486

    Web of Science

    researchmap

  • A Proposal of Coding Rule Learning Function in Java Programming Learning Assistant System

    Nobuo Funabiki, Takuya Ogawa, Nobuya Ishihara, Minoni Kuribayashi, Wen-Chung Kao

    PROCEEDINGS OF 2016 10TH INTERNATIONAL CONFERENCE ON COMPLEX, INTELLIGENT, AND SOFTWARE INTENSIVE SYSTEMS (CISIS)   561 - 566   2016

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    Recently, Java has been educated in many universities and professional schools due to reliability, portability, and scalability. However, because of its limited time in Java programming courses, coding rules arc rarely educated. As a result, codes made by students become far from readable codes. In this paper, we propose a coding rule learning function using static code analyzers in Java Programming Learning Assistant System (JPLAS), targeting students who have accomplished the grammar learning and are going to write practical codes for final projects. Coding rules for this function consist of naming rules, coding styles, and potential problems. We evaluate the improvement of readability in four codes refined by this function and the usability of this function through the questionnaires completed by five students. In future studies, we expect that this function will be employed in Java programming courses.

    DOI: 10.1109/CISIS.2016.94

    Web of Science

    researchmap

  • A workbook design for fill-in-blank problems in Java programming learning assistant system

    Nobuo Funabiki, Khin Khin Zaw, Wen-Chung Kao

    The 11-th International Conference on Broadband and Wireless Computing, Communication and Applications (BWCCA2016)   331 - 342   2016

     More details

    Authorship:Lead author   Language:English  

    researchmap

  • Analysis of fill-in-blank problem solutions and extensions of blank element selection algorithm for Java programming learning assistant system

    Nobuo Funabiki, Tana, Khin Khin Zaw, Nobuya Ishihara, Wen-Chung Kao

    The World Congress on Engineering and Computer Science 2016 (WCECS 2016)   237 - 242   2016

     More details

    Authorship:Lead author   Language:English  

    researchmap

  • A Proposal of Recipe Conversion Algorithm for Cooking-Step Schedule Optimization

    115 ( 221 )   67 - 72   2015.9

     More details

    Language:Japanese  

    CiNii Article

    researchmap

  • BS-6-2 A Blank Line Selection Algorithm for Value Trace Problem in Java Programming Learning Assistant System(BS-6.Network and service Design, Control and Management)

    Zaw Khin Khin, Funabiki Nobuo

    Proceedings of the Society Conference of IEICE   2015 ( 2 )   "S - 19"-"S-20"   2015.8

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    To cultivate the code reading capability of Java novice students, we have studied the value trace problem for the Web-based Java Programming Learning Assistant System (JPLAS). This problem asks students to trace actual values of important variables in fundamental data structure or algorithms. To realize the automatic problem generation, the whole sequence of changing data of such variables are output in lines by executing the code for the data structure or algorithm. Then, output data lines that have difference from their previous lines are blanked to be filled. In this paper, we propose the blank line selection algorithm for the value trace problem, and show an example of the generated problem for the insertion sort algorithm.

    CiNii Article

    CiNii Books

    researchmap

  • A Cooking-Step Scheduling Algorithm with Guidance System for Homemade Cooking

    Yukiko Matsushima, Nobuo Funabiki

    IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS   E98D ( 8 )   1439 - 1448   2015.8

     More details

    Language:English   Publisher:IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

    Homemade cooking plays a key role for a healthy and cost-efficient life. Unfortunately, preparing multiple dishes is generally time-consuming. In this paper, an algorithm is proposed to minimize the cooking time by scheduling the cooking-step of multiple dishes. The cooking procedure of a dish is divided into a sequence of six types of cooking-steps to consider the constraints in cooks and cooking utensils in a kitchen. A cooking model is presented to optimize the cooking-step schedule and estimate the cooking time for a given starting order of dishes under various constraints of cooks and utensils. Then, a high-quality schedule is sought by repeating the generation of a new order and the model application based on exhaustive search and simulated annealing. Our simulation results and cooking experiments confirm the effectiveness of our proposal.

    DOI: 10.1587/transinf.2015EDP7048

    Web of Science

    researchmap

  • An Active Access-Point Configuration Algorithm for Wireless Local Area Networks with Heterogeneous Devices (ネットワークシステム)

    セリム アル マムン ムハマド, エズハルル イスラム ムハマド, 舩曵 信生

    電子情報通信学会技術研究報告 = IEICE technical report : 信学技報   115 ( 159 )   147 - 152   2015.7

     More details

    Language:English   Publisher:電子情報通信学会  

    CiNii Article

    CiNii Books

    researchmap

  • Performance evaluations for multi-user MIMO using WIMNET simulator

    115 ( 159 )   141 - 146   2015.7

     More details

  • An Implementation and Evaluation of Job Scheduling Methods for User-PC Computing System

    AOYAGI Yuki, FUNABIKI Nobuo, FUKUSHI Masaru

    IEICE technical report   114 ( 477 )   553 - 558   2015.3

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    We have proposed and implemented User-PC computing (UPC) system as a parallel computing platform using idling computing resources (CPU cycles) in personal computers (PCs) of members in the same organization such as a laboratory in a university. Because the original UPC system has adopted a sequential job scheduling method which assigns new jobs to workers in the descending order of their performance up to its permissible number, some workers may not be assigned any job. In this paper, we propose static and dynamic round-robin (RR)job scheduling methods of assigning a predefined number of new jobs to the workers in round-robin fashion. The dynamic RR method considers the change of the worker's performance by using the CPU time of recent jobs. Our experiment results show that when the performance difference among workers and the number of jobs are small, both RR methods performs well, and when both of them are large, the dynamic RR method shows better performance.

    CiNii Article

    CiNii Books

    researchmap

  • Active Access Point Selection Algorithm for Scalable Wireless Mesh Networks

    FUJITA Sho, FUNABIKI Nobuo

    IEICE technical report   114 ( 477 )   427 - 432   2015.3

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    The wireless Internet-access mesh network (WIMNET) can realize an inexpensive scalable Internet-access network by using multiple access points (APs) connected by wireless links. We have proposed the active AP selection algorithm of selecting active APs for high-speed and low-cost communications in large WIMNET. In this paper, we extend this algorithm to improve the performance of WIMNET by introducing mobile routers. Besides, we present the plural AP deactivation procedure using link speeds for better practicality. We show the effectiveness of the proposals through simulations in two instances.

    CiNii Article

    CiNii Books

    researchmap

  • Javaプログラミング授業におけるエレメント空欄補充問題の実践

    塔 娜, 舩曵 信生, 石原 信也

    研究報告コンピュータと教育(CE)   2015 ( 11 )   1 - 8   2015.2

     More details

    Language:Japanese  

    本グループでは,プログラミング言語 Java の学習支援のために,Web を用いた Java プログラミング学習支援システム JPLAS(Java Programming Learning Assistant System) を開発している.JPLAS では,Java の初学者を対象としたエレメント空欄補充問題を提供しており,グラフ理論を用いた解の一意性を充たす問題生成のためのアルゴリズムを提案している.今回,本アルゴリズムを用いてエレメント空欄補充問題を生成し,本学科の Java プログラミング授業で実践活用した結果を報告する.

    CiNii Article

    CiNii Books

    researchmap

  • 学生用PCを用いたユーザPCコンピューティングシステムのWebインターフェース

    金 奉洙, 舩曵 信生

    研究報告コンピュータと教育(CE)   2015 ( 7 )   1 - 8   2015.2

     More details

    Language:Japanese  

    本グループでは,研究室内の学生が使用するパーソナルコンピュータ (PC) の空き資源を利用して,大規模シミュレーションなどの計算プロジェクトを実行する,ユーザ PC コンピューティングシステム UPC(User-PC Computing System) を開発している.UPC では,大規模コンピューティング環境の実現に関して,運営コストの低減と利便性の向上の実現を目指している.UPC では,計算プロジェクトの実行には,コマンド入力が必要となっており,その知識に乏しいユーザには UPC の使用が容易ではない.そこで本研究では,ブラウザで UPC の利用を可能とするために,Web 技術を用いた UPC ユーザインターフェース機能を開発する.UPC サーバ間とファイル共有ソフトを用いて連携することで,異なる複数の UPC へのインターフェース機能の提供を可能としている.本稿では,今回開発した UPC インターフェース機能の構成を示す.

    CiNii Article

    CiNii Books

    researchmap

  • Javaコードのクラス間連携理解のためのコアステートメント抽出アルゴリズム

    石原 信也, 舩曵 信生

    研究報告コンピュータと教育(CE)   2015 ( 10 )   1 - 8   2015.2

     More details

    Language:Japanese  

    Java プログラミング学習では,既存のソースコードを読み,その処理や構造を理解することが有効である.このコードリーディングをプログラミング教育に取り入れるためには,学習者がソースコードを理解したか否かを確認する方法が必要となる.そのため本グループでは,ソースコード中の肝要なステートメント (コアステートメント) を空欄とし,その記述を要求する,ステートメント空欄補充問題の提案と授業適用を行っている.本研究では,ソースコード中の空欄化すべきコアステートメント抽出アルゴリズムを提案する.本アルゴリズムでは,コアステートメントとして,1) 要求仕様を充たすためのアルゴリズム要素,2) オブジェクト指向言語の特徴であるクラス間連携要素,3) データベースなど外部機能との連携要素,の 3 種類を想定し,それぞれの抽出法を定義している.提案アルゴリズムを実装し,5 つの Java ソースコードに適用して得られたコアステートメントを,Java 学習者による抽出結果と比較した.その結果,両者に高い一致がみられ,提案アルゴリズムの有効性が確認された.

    CiNii Article

    CiNii Books

    researchmap

  • Revocable Group Signatures with Compact Revocation List Using Accumulators

    Toru Nakanishi, Nobuo Funabiki

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E98A ( 1 )   117 - 131   2015.1

     More details

    Language:English   Publisher:IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

    A group signature scheme allows a group member to anonymously sign a message on behalf of the group. One of the important issues is the member revocation, and lots of revocable schemes have been proposed so far. A scheme recently proposed by Libert et al. achieves that O(1) or O(log N) efficiency of communication and computation except for the revocation list size (also the revocation cost), for the total number of members N and the number of revoked members R. However, since a signature is required for each subset separated from the set of non-revoked members, the size is about 900R Bytes in the 128-bit security. In the case of R = 100, 000, it amounts to about 80MB. In this paper, we extend the scheme to reduce the revocation list (also the revocation cost), by accumulating T subsets, which is signed for the revocation list. The revocation list size is reduced by 1/T. Unfortunately, the public key size, membership certificate size and the cost of a witness computation needed for signing increase related to T.

    DOI: 10.1587/transfun.E98.A.117

    Web of Science

    researchmap

  • Cross-Layer Selective Routing for Active Access-Point Minimization in Wireless Mesh Network

    I-Wei Lai, Wen-Chung Kao, Nobuo Funabiki

    2015 IEEE INTERNATIONAL CONFERENCE ON CONSUMER ELECTRONICS - TAIWAN (ICCE-TW)   482 - 483   2015

     More details

    Language:English   Publisher:IEEE  

    A Wireless Internet-access Mesh NETwork (WIMNET) provides the scalable and reliable internet access through the multiple access points (APs) and wireless relay communications. In particular, by redundantly deploying APs in the network field, the WIMNET becomes robust to the link or AP failure. However, these redundant APs increase the power consumption, and thus the number of active APs should be minimized by the selective routing without loss of the transmission performance. In this work, we propose to reinvent such selective routing algorithm by exploiting physical-layer technologies. An exemplar numerical simulation demonstrates that this cross-layer selective routing can further minimize the number of APs, leading to less operational costs in WIMNET.

    DOI: 10.1109/ICCE-TW.2015.7217010

    Web of Science

    researchmap

  • An Operator Fill-in-blank Problem for Algorithm Understanding in Java Programming Learning Assistant System

    Nobuo Funabiki, Shin Sasaki, Ta Na, Wen-Chung Kao

    2015 IEEE 4TH GLOBAL CONFERENCE ON CONSUMER ELECTRONICS (GCCE)   346 - 347   2015

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    A Web-based Java Programming Learning Assistant System (JPLAS) has been developed to help novice students studying Java programming through self-learning. As one function, JPLAS provides the fill-in-blank problem that requests filling in the blank elements in a given code with several blanks. Currently, reserved words, identifiers, or control symbols can be blanked to have unique correct answers, which may be solved without reading the code carefully. In this paper, we propose to additionally blank operators in conditional expressions of core statements in the code so that students can understand the structure to realize the specification. For preliminary evaluations, we generated six operator fill-in-blank problems, and assigned them to students where the number of answer submissions per blank has increased from that of conventional problems.

    DOI: 10.1109/GCCE.2015.7398539

    Web of Science

    researchmap

  • A proposal of statement fill-in-blank problem using program dependence graph in Java programming learning assistant system

    Nobuya Ishihara, Nobuo Funabiki, Wen-Chung Kao

    Information Engineering Express   1 ( 3 )   19 - 28   2015

     More details

    Language:English  

    researchmap

  • A proposal of value trace problem for algorithm code reading in Java programming learning assistant system

    Khin Khin Zaw, Nobuo Funabiki, Wen-Chung Kao

    Information Engineering Express   1 ( 3 )   9 - 18   2015

     More details

    Language:English  

    researchmap

  • A Worker Implementation on Windows OS for User-PC Computing System

    Nobuo Funabiki, Yusuke Asai, Yuuki Aoyagi, Wen-Chung Kao

    PROCEEDINGS OF 2015 THIRD INTERNATIONAL SYMPOSIUM ON COMPUTING AND NETWORKING (CANDAR)   279 - 282   2015

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    Previously, we have proposed and implemented the User-PC computing (UPC) system as a highly parallel computing platform using idling CPU cycles in members' personal computers (PCs) of the same organization such as a laboratory in a university. This implementation for both the UPC master and the UPC worker covers only Linux OS. However, currently a lot of PCs adopt Windows OS. In this paper, we present an implementation of the UPC worker for Windows OS based on the implementation for Linux OS. During the implementation, we realize the CPU usage limitation and the automatic start-up of the worker program which can reduce loads for PC owner, aside from basic functions of master communications and job executions. Through evaluations, we conclude that the CPU usage rate does not exceed the given limitation except for starting time, and the job execution time on Windows is about twice the use of that on Linux.

    DOI: 10.1109/CANDAR.2015.17

    Web of Science

    researchmap

  • A Function for Generating Debugging Questions in a Java Programming Learning Assistant System

    Shingo Yamaguchi, Takato Mohri, Nobuo Funabiki

    2015 IEEE 4TH GLOBAL CONFERENCE ON CONSUMER ELECTRONICS (GCCE)   350 - 353   2015

     More details

    Language:English   Publisher:IEEE  

    Today many universities offer courses for learning Java programming. Debugging cannot be avoided in programming. Nevertheless, there are not many chances for students to debugging programs, particularly written by another person. In this paper, for increasing that chance, we propose a function for generating a new kind of questions that are called debugging questions. A debugging question requires students to debug a program mixed with bugs. This function provides three ways of mixing bugs: deletion of reserved words, swapping of variables, and replacement by lists. We implemented this function into a Java programming learning assistant system, called JPLAS. We also discussed the usefulness by evaluating the function.

    DOI: 10.1109/GCCE.2015.7398573

    Web of Science

    researchmap

  • An Extension of Statement Fill-in-blank Problem in Java Programming Learning Assistant System

    Nobuya Ishihara, Nobuo Funabiki, Ta Na, Wen-Chung Kao

    2015 IEEE 4TH GLOBAL CONFERENCE ON CONSUMER ELECTRONICS (GCCE)   354 - 358   2015

     More details

    Language:English   Publisher:IEEE  

    To assist Java programming studies, we have developed a Web-based Java Programming Learning Assistant System (JPLAS). As one function in JPLAS, it provides a statement fill-in-blank problem that asks students to fill in proper statements to blanked ones in a Java code, so as to cultivate simultaneous code reading and writing abilities. Previously, we blanked only the core statement in a code with one class using the Program Dependence Graph (PDG), where we do not consider the features of object-oriented programming in Java that uses multiple classes and collaborations with other systems such as database. In this paper, we extend the statement fill-in-blank problem to deal with these features. We verify the effectiveness of our proposal through the Java programming course at our department.

    DOI: 10.1109/GCCE.2015.7398543

    Web of Science

    researchmap

  • Correlation Analysis of Fill-in-blank Problem Solutions to Final Programming Results in Java Programming Course

    Ta Na, Nobuo Funabiki, Nobuya Ishihara, Wen-Chung Kao

    2015 IEEE 4TH GLOBAL CONFERENCE ON CONSUMER ELECTRONICS (GCCE)   348 - 349   2015

     More details

    Language:English   Publisher:IEEE  

    To assist Java programming educations, we have developed a Web-based Java Programming Learning Assistant System (JPLAS). JPLAS provides fill-in-blank problems to study the Java grammar and fundamental programming by filling blank elements that are composed of reserved words, identifiers, and control symbols in a high-quality code. During the last semester, we assigned 121 problems with 1,552 questions to 46 students taking our Java programming course. In this paper, we analyze correlations of problem solving results of students to their final programming results.

    DOI: 10.1109/GCCE.2015.7398542

    Web of Science

    researchmap

  • Active Access-Point Configuration Algorithm with Dynamic Mobile Router Placement for Elastic WLAN System

    Md. Selim Al Mamun, Md. Ezharul Islam, Nobuo Funabiki, I-Wei Lai

    PROCEEDINGS OF 2015 THIRD INTERNATIONAL SYMPOSIUM ON COMPUTING AND NETWORKING (CANDAR)   246 - 252   2015

     More details

    Language:English   Publisher:IEEE  

    Recently, a variety of wireless access points (APs) have been deployed by many organizations to meet different traffic demands. Previously, we proposed an active AP configuration algorithm that activates or deactivates heterogeneous AP devices depending on the traffic demand and network topology, in order to realize the elastic Wireless Local-Area Network (WLAN) system. Unfortunately, in this algorithm, the locations of the mobile routers have been fixed as the algorithm input, although they can be placed flexibly as portable APs using cellular networks. In this paper, we consider the elastic WLAN system with mobile routers which can be placed flexibly. The dynamic mobile router placement is proposed for the active AP configuration algorithm to meet stringent traffic requirements. Specifically, if some hosts fail to meet the throughput requirements, the locations of additional mobile routers are dynamically determined by applying the Kmeans algorithm to maximize the number of those failed hosts in its coverage. The effectiveness of this location determination is demonstrated by numerical examples with three network scenarios.

    DOI: 10.1109/CANDAR.2015.55

    Web of Science

    researchmap

  • Extensions of Access-Point Aggregation Algorithm for Large-scale Wireless Local Area Networks

    Islam Md. Ezharul, Funabiki Nobuo, Nakanishi Toru

    IJNC   5 ( 1 )   200 - 222   2015

     More details

    Language:English   Publisher:IJNC Editorial Committee  

    Recently, many organizations such as universities and companies have deployed wireless local area networks (WLANs) to cover the whole site for ubiquitous network services. In these WLANs, wireless access-points (APs) are often managed independently by different groups such as laboratories or departments. Then, a host may detect signals from multiple APs, which can degrade the communication performance due to radio interferences among them and increase operational costs. Previously, we proposed the AP aggregation algorithm to solve this problem by minimizing the number of active APs through aggregating them using the virtual AP technology. However, our extensive simulations in various instances found that 1) the minimization of active APs sometimes excessively degrades the network performance, and 2) the sequential optimization of host associations does not always reach optimal where slow links are still used. In this paper, we propose two extensions of the AP aggregation algorithm to solve these problems by 1) ensuring the minimum average throughput for any host by adding active APs and 2) further optimizing host associations by changing multiple hosts simultaneously in the host association finalization phase. We verify the effectiveness through simulations in four network instances using the WIMNET simulator.

    DOI: 10.15803/ijnc.5.1_200

    CiNii Article

    researchmap

    Other Link: https://jlc.jst.go.jp/DN/JLC/20005432460?from=CiNii

  • Practices of Fill-in-blank Problems in Java Programming Course

    Nobuo Funabiki Tana, Nobuya Ishihara

    2015 IEEE INTERNATIONAL CONFERENCE ON CONSUMER ELECTRONICS - TAIWAN (ICCE-TW)   120 - 121   2015

     More details

    Language:English   Publisher:IEEE  

    To assist Java programming educations, we have developed a Web-based Java Programming Learning Assistant System (JPLAS). JPLAS provides fill-in-blank problems to study the Java grammar by filling blank elements in a high-quality code that are composed of reserved words, identifiers, and control symbols. A graph-based blank element selection algorithm has been proposed to automatically select as many blanks as possible that have grammatically correct unique answers. In this paper, we show and discuss their application results to a Java programming course in our department.

    DOI: 10.1109/ICCE-TW.2015.7216810

    Web of Science

    researchmap

  • Concept of User-PC Computing System

    Nobuo Funabiki, Bongsu Kim, Yuki Aoyagi

    2015 IEEE INTERNATIONAL CONFERENCE ON CONSUMER ELECTRONICS - TAIWAN (ICCE-TW)   480 - 481   2015

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    The User-PC computing system (UPC) is a technology of realizing a parallel computing environment using idling computing resources (CPU cycles) in Personal Computers (PCs) of members in the same organization or group such as a laboratory in a university and a section in a company. UPC can resolve drawbacks in the registration of computing projects, the reliability of computing results, and the continuity of computations that may often happen in Volunteer Computing (VC) systems using voluntary PCs in the Internet. Thus, UPC can be easily and comfortably used by computing users. In this paper, we show the concept of UPC and preliminary evaluations.

    DOI: 10.1109/ICCE-TW.2015.7217009

    Web of Science

    researchmap

  • A proposal of graph-based blank element selection algorithm for Java programming learning with fill-in-blank problems

    Tana, Nobuo Funabiki, Nobuya Ishihara

    The International MultiConference of Engineers and Computer Scientists 2015 (IMECS 2015)   2015

     More details

    Language:English  

    researchmap

  • Practices of Cooking-Step Scheduling Algorithm for Homemade Cooking

    Yukiko Matsushima, Nobuo Funabiki

    2015 IIAI 4TH INTERNATIONAL CONGRESS ON ADVANCED APPLIED INFORMATICS (IIAI-AAI)   500 - 505   2015

     More details

    Language:English   Publisher:IEEE  

    Homemade cooking is essential not only for keeping healthy and cost-efficient dietary lives but also for constructing good family relationships and identities. Previously, we proposed the cooking-step scheduling algorithm to help homemade cooking by finding a schedule of applying the cooking-steps for multiple dishes with minimal cooking time. In this algorithm, the cooking procedure for each dish is divided into a sequence of six types of cooking-steps to consider the constraints in cooks and cooking utensils in a kitchen. In this paper, we conduct practices of the algorithm in actually cooking dishes by following the generated schedules to show the effectiveness.

    DOI: 10.1109/IIAI-AAI.2015.189

    Web of Science

    researchmap

  • A Concept of Value Trace Problem for Java Code Reading Education

    Khin Khin Zaw, Nobuo Funabiki

    2015 IIAI 4TH INTERNATIONAL CONGRESS ON ADVANCED APPLIED INFORMATICS (IIAI-AAI)   253 - 258   2015

     More details

    Language:English   Publisher:IEEE  

    To assist Java programming educations, we have developed a Web-based Java Programming Learning Assistant System (JPLAS). JPLAS provides the fill-in-blank problem to help novice students studying Java programming at home, where some elements in a high-quality code including reserved words, identifiers, and control symbols are blanked to be filled by students. Unfortunately, this problem may be solved without reading out the algorithm in the code if students are familiar with Java grammar to some extent. In this paper, to further cultivate the code reading capability of students, we propose a concept of the value trace problem to ask the actual values of important variables in a code implementing some fundamental data structure or algorithm. A value trace problem can be generated by: 1) selecting a high-quality class code for the algorithm to be studied, 2) making the main class to instantiate the class in 1) if it does not contain the main method, 3) adding the functions to output variable values in questions into a text file, 4) preparing the input file to the code in 3) if necessary, 5) running this code to obtain the set of variable values in the text file, 6) blanking some values from the text file to be filled by students, and 7) uploading the final code, the blanked text file, and the correct answer file into the JPLAS server, and adding the brief description on the algorithm for a new assignment. To verify the feasibility of this concept, we manually generated five problems and asked four students with high Java programming skills in our group to solve them. Then, we analyzed the difficulty of the value trace problem for Quick Sort.

    DOI: 10.1109/IIAI-AAI.2015.188

    Web of Science

    researchmap

  • A Proposal of Statement Fill-in-blank Problem in Java Programming Learning Assistant System

    Nobuya Ishihara, Nobuo Funabiki

    2015 IIAI 4TH INTERNATIONAL CONGRESS ON ADVANCED APPLIED INFORMATICS (IIAI-AAI)   247 - 252   2015

     More details

    Language:English   Publisher:IEEE  

    As a reliable, portable, and practical programming language, Java has been educated in many universities and professional schools. To assist Java educations, we have developed a Web-based Java Programming Learning Assistant System (JPLAS). JPLAS provides the element fill-in-blank problem and the code writing problem. The former problem is designed for novice students to study the grammar and writing style of Java by filling correct words to the blanks in a given Java code that are automatically marked by checking coincidences with correct ones. The latter problem is for students to study writing Java codes for specifications described in natural language that are automatically verified using the test-driven development (TDD) method. Unfortunately, the transition between two problems is not smooth due to the difference in difficulties. In this paper, we propose the statement fill-in-blank problem in JPLAS to fill the gap by asking students to write one whole statement in a code where the correctness is verified by the TDD method. The blank statement is selected by generating the Program Dependence Graph (PDG) of the code and finding the statement that has the largest dependence with other ones. We verify the effectiveness of our proposal through applications to the Java programming course in our department.

    DOI: 10.1109/IIAI-AAI.2015.192

    Web of Science

    researchmap

  • An Anonymous Reputation System with Reputation Secrecy for Manager

    Toru Nakanishi, Nobuo Funabiki

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E97A ( 12 )   2325 - 2335   2014.12

     More details

    Language:English   Publisher:IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

    In anonymous reputation systems, where after an interaction between anonymous users, one of the users evaluates the peer by giving a rating. Ratings for a user are accumulated, which becomes the reputation of the user. By using the reputation, we can know the reliability of an anonymous user. Previously, anonymous reputation systems have been proposed, using an anonymous e-cash scheme. However, in the e-cash-based systems, the bank grasps the accumulated reputations for all users, and the fluctuation of reputations. These are private information for users. Furthermore, the timing attack using the deposit times is possible, which makes the anonymity weak. In this paper, we propose an anonymous reputation system, where the reputations of users are secret for even the reputation manager such as the bank. Our approach is to adopt an anonymous credential certifying the accumulated reputation of a user. Initially a user registers with the reputation manager, and is issued an initial certificate. After each interaction with a rater, the user as the ratee obtains an updated certificate certifying the previous reputation summed up by the current rating. The update protocol is based on the zero-knowledge proofs, and thus the reputations are secret for the reputation manager. On the other hand, due to the certificate, the user cannot maliciously alter his reputation.

    DOI: 10.1587/transfun.E97.A.2325

    Web of Science

    researchmap

  • A Proposal of Blank Element Selection Algorithm for Java Programming Learning

    Tana, FUNABIKI Nobuo, ISHIHARA Nobuya

    Technical report of IEICE. SS   114 ( 271 )   1 - 6   2014.10

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    The programming language Java has been widely used in industries and educated in educational institutes due to its excellent developing environments, reliability, and portability. To assist Java educations, we have developed a Web-based Java Programming Learning Assistant System (JPLAS). JPLAS provides the fill-in-blank problem for Java novice students to learn it by filling proper elements into blanks in a Java code. In the paper, we propose a blank element selection algorithm to find a feasible problem that has the unique solution for any blank. This algorithm first generates a simple graph such that a vertex represents a candidate element in the code and an edge is made between two vertices that can be blanked simultaneously. Then, it extracts a clique of the graph to maximize the number of feasible blanks. We applied the algorithm to 100 Java codes and checked the uniqueness of the solutions manually. The results show that by showing the execution results of the three codes, we confirmed the uniqueness of the solutions.

    CiNii Article

    CiNii Books

    researchmap

  • A Study of Access-Point Allocation Algorithm for Scalable Wireless Mesh Networks in Indoor Environments

    FARAG Tamer, FUNABIKI Nobuo, HASSAN Walaa

    IEICE technical report   114 ( 252 )   1 - 6   2014.10

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Previously, we proposed an access-point (AP) allocation algorithm for scalable Wireless Internet-access Mesh NETwork (WIMNET) with multiple gateways (GWs) and the hop count limitation. The algorithm for K GWs consists of 1) the partition of the network field into K clusters by the K-means algorithm, 2) the sequential AP allocation in each cluster by our AP allocation algorithm for one GW, and 3) the simultaneous routing in K clusters by our routing algorithm considering multiple GWs and the hop count limitation. In this paper, we study the AP allocation algorithm in indoor environments as common fields for WIMNET. We assume that one wall drops the transmission speed by 15%, which is equivalent to 10m increase of the distance in an open space. To handle situations unsuitable to the K-means algorithm where plural GWs are closely located in neighboring rooms, we regard these GWs as one virtual GW, and apply 1) and 2) in the algorithm. Then, we apply 3) to the individual real GWs. We verify the effectiveness of our proposal through simulations in an indoor field using the WIMNET simulator.

    CiNii Article

    CiNii Books

    researchmap

  • A Consideration of Extended Wireless Internet-Access Mesh Network Simulator for MU-MIMO

    TAJIMA Shigeto, FUNABIKI Nobuo, HIGASHINO Teruo

    IEICE technical report   114 ( 252 )   7 - 12   2014.10

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Recently, IEEE802.11ac has been focused as a new high-speed wireless communication protocol. IEEE802.11ac adopts the frame aggregation that can reduce communication overheads by aggregating multiple frames into one big frame and the MU-MIMO (Multi-User Multi-Input-Multi-Output) that can improve the channel efficiency by allowing simultaneous transmissions to multiple destinations using the same channel. We have studied the efficient use of this protocol in the Wireless Internet-access Mesh NETwork (WIMNET) that provides an expandable Internet-access network by connecting multiple access-points through wireless links. In this paper, we present an extension of the WIMNET simulator that has been developed by our group in considering frame aggregation and MU-MIMO in IEEE802.11ac to evaluate the performance of WIMNET using this protocol. We evaluate the effect of MU-MIMO in WIMNET through simulations using the extended WIMNET simulator.

    CiNii Article

    CiNii Books

    researchmap

  • Robustness Evaluations of Cooking-Step Scheduling Algorithm under Operation Time Fluctuations

    MATSUSHIMA Yukiko, FUNABIKI Nobuo

    114 ( 222 )   5 - 10   2014.9

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    To assist homemade cooking of busy people such as working people, child-growing families, and students, we have proposed a cooking-step scheduling algorithm for multiple dishes such that the total cooking time be minimized. For a given set of dishes where the cooking procedure for each dish is composed of a sequence of cooking-steps requiring certain time, this algorithm generates an optimal schedule for applying the cooking-steps of the dishes by considering the constraints of the cooks and the instruments. In this paper, we evaluate the robustness of this algorithm under time fluctuations in real cooking that can happen by variations of the proficiency of cooks and the cooking environment. First, we developed the evaluation cooking model to simulate the cooking process for a given schedule and time, and conducted simulations with randomly fluctuated time within 30% of the original one. Then, we actually cooked four dishes using the schedule found by the algorithm. In any result, the variation of the total cooking time is small compared to changes of cooking-step time. Thus, the robustness of the algorithm is confirmed.

    CiNii Article

    CiNii Books

    researchmap

  • BS-6-2 Throughput Measurements in Big Room with Different Access Point Locations for IEEE 802.11ac Wireless Networks(BS-6.Network and service Design, Control and Management)

    CHEW Chang Choon, FUNABIKI Nobuo

    Proceedings of the Society Conference of IEICE   2014 ( 2 )   "S - 38"-"S-39"   2014.9

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    The IEEE802.11ac wireless communication protocol has been introduced for high-speed wireless networks. In this paper, we provide throughput measurement results by Transmission Control Protocol (TCP) in a big room with various access point (AP) locations. Our measurement results show that TCP throughputs are greatly affected by AP locations for two-AP cases and are not affected for one-AP cases.

    CiNii Article

    CiNii Books

    researchmap

  • BS-6-1 AN EXTENSION OF ACCESS-POINT AGGREGATION ALGORITHM FOR HOST MOBILITY(BS-6.Network and service Design, Control and Management)

    Islam Md Ezharu, Funabiki Nobuo

    Proceedings of the Society Conference of IEICE   2014 ( 2 )   "S - 36"-"S-37"   2014.9

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    The AP aggregation algorithm has been proposed to reduce the number of active APs in overlapped WLANs by aggregating them to solve the problem of performance degradation due to interferences, and increased operational cost. However, this algorithm does not consider the mobility of hosts, although they usually join or leave the network randomly. In this paper, we propose an extension of the AP aggregation algorithm to deal with the mobility by considering the probability of each host to stay active. We verify the effectiveness of this extension through simulations using the WIM- NET simulator.

    CiNii Article

    CiNii Books

    researchmap

  • Efficient Proofs for Monotone Formulas on Attributes Excluding Restriction in Anonymous Credential System

    SADIAH Shahidatul, NAKANISHI Toru, FUNABIKI Nobuo

    Technical report of IEICE. ISEC   114 ( 203 )   21 - 26   2014.9

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    An anonymous credential system on attributes allows a user to convince a service provider anonymously that he/she owns the certified attributes. Previously, we proposed an anonymous credential scheme to prove the satisfaction of a monotone formula when only one attribute is true for any OR relation. A monotone formula represents any combination of AND relations and OR relations. However, this system has a drawback that it cannot verify a user's certificate such that two or more attributes for an OR relation are true. In this paper, we propose an extended scheme for proofs of arbitrary monotone formula by adopting Linear Homonorphic (LH) signature scheme to generate a certificate that contains the minimum attribute set as required in the verification.

    CiNii Article

    CiNii Books

    researchmap

  • Robustness Evaluations of Cooking-Step Scheduling Algorithm under Operation Time Fluctuations

    38 ( 36 )   5 - 10   2014.9

     More details

  • Throughput Evaluations Using NS-2 for Access-Point Aggregation Algorithm in IEEE802.11n Wireless LANs

    HASSAN Walaa, FUNABIKI Nobuo, ISLAM Md. EZHARUL, FARAG Tamer

    IEICE technical report. Information networks   114 ( 110 )   25 - 30   2014.6

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    The IEEE 802.11-based WiFi wireless technology has been commonly used in efficient wireless local area networks (WLANs). Recently, the IEEE 802.11n protocol among several ones has become popular as higher throughput operations with up to 600 Mbps. For a large-scale WLAN with multiple access-points (APs), we have proposed an access-point aggregation algorithm to minimize the operation cost while maximizing the performance. However, the effectiveness of this algorithm has been verified only through the WIMNET simulator that has been developed by our group as a simple network simulator. In this paper, we implement the modified 802.11n module that has been introduced by Wang and Wei on the NS-2 version 2.34, and evaluate the performance of this algorithm through simulations using it.

    CiNii Article

    CiNii Books

    researchmap

  • An Extension of Access Point Allocation Algorithm for Wireless Mesh Networks with Multiple Gateways and Maximum Hop Limitation

    FARAG Tamer, FUNABIKI Nobuo, HASSAN Walaa

    IEICE technical report. Information networks   114 ( 110 )   31 - 36   2014.6

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As an inexpensive, scalable Internet-access wireless network, we have studied design optimizations of a Wireless Internet-access Mesh NETwork (WIMNET) that adopts multiple access-points (APs) connected by Wireless Distribution System (WDS). In WIMNET, the proper allocation of APs is essential in ensuring the communication quality while reducing the installation and management costs. Thus, previously we proposed an AP allocation algorithm for WIMNET where only one gateway (GW) to the Internet exists and no hop limitation is imposed. In this study, we extend this algorithm for multiple GWs and the maximum hop limitation, which is common for large-scale WIMNET using WDS. First, for given K GWs, we partition the whole network into K sub-networks using the k-means algorithm such that the hosts in each sub-network connects with one GW. Then, we apply the previous AP allocation algorithm to each sub-network sequentially to allocate the APs. Finally, we apply our existing routing algorithm to obtain the routing path satisfying the hop limitation. We verify the effectiveness of this extended algorithm through simulations in one instance using the WIMNET simulator.

    CiNii Article

    CiNii Books

    researchmap

  • An Extension of Routing Algorithm for Wireless Mesh Networks Considering Frame Aggregation

    TANI Yuma, FUNABIKI Nobuo, TAJIMA Shigeto

    IEICE technical report. Information networks   114 ( 110 )   19 - 24   2014.6

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As a flexible inexpensive Internet-access network, we have studied the Wireless Internet-access Mesh NETwork (WIMNET) that is composed of wireless interconnected Access-Points (APs). We have proposed routing algorithm for WIMNET under realistic environments such as 1) multiple gateways, 2) communication speed changes, and 3) the limited number of hops. In this study, we extend the algorithm by considering the frame aggregation adopted in the IEEE802.11ac high-speed wireless communication protocol. We verify the effectiveness of our proposal through simulating three instances using the WIMNET simulator.

    CiNii Article

    CiNii Books

    researchmap

  • A Draft Coding Rule for Codes in Java Programming Learning Assistant System

    ISHIHARA Nobuya, FUNABUKI Nobuo

    IEICE technical report. Education technology   114 ( 82 )   57 - 62   2014.6

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    We have developed the Java programming learning support system JPLAS as a Web application using JSP, Servlet, and Java Beans, to support repetitive self-learning of Java programming through automatic verifications of answers from students to assignments. Because the codes in JPLAS have been implemented by students who have newly joined our group and taken over the codes from seniors, their managements and updates have become complicated. At the same time, they do not follow the Web standard including HTML5 and CSS3 that has become popular to realize rich Web clients. In this paper, we propose a draft coding rule to implement codes in JPLAS following the Web standard. By adopting HTML5 and Ajax, this rule makes it possible implementing codes that can be easily maintained by avoiding redundancy.

    CiNii Article

    CiNii Books

    researchmap

  • An Extension of Fill-in-blank Problem Generation Algorithm for Java Programming Learning Assistant System

    Tana, FUNABUKI Nobuo, ISHIHARA Nobuya, OGAWA Takuya

    IEICE technical report. Education technology   114 ( 82 )   63 - 68   2014.6

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    To help Java programming educations in universities and professional schools, we have developed a Web-based Java Programming Learning Assistant System (JPLAS). Since JPLAS provides the fill-in-blank problem function for Java novice students, we have proposed a graph-based fill-in-blank problem generation algorithm for it. In this paper, we extend this algorithm for blanking grammatically related words so as to encourage students studying the Java grammar more deeply. Besides, we evaluate generated problems with up to 20 blanks in a Java code where we have limited maximally 10 blanks previously. We applied problems by the extended algorithm to middle level students and found that the length, numbers of classes and methods, the difficulty of the implemented algorithm, and the existence of comments in the Java code have large influences on the correct solution rate.

    CiNii Article

    CiNii Books

    researchmap

  • An Implementation of Statement Fill-in-blank Problem Function for Java Programming Learning Assistant System

    ISHIHARA Nobuya, FUNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report. Education technology   113 ( 482 )   35 - 40   2014.3

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    We have proposed a Web-based JPLAS (Java Programming Learning Assistant System) to help students studying Java programming by themselves at home. By adopting the Test-Driven Development (TDD) method to verify the codes from students, JPLAS aims to reduce loads of teachers in addition to enhancing learning activities of students. In this paper, we propose and implement the statement fill-in-blank problem function in JPLAS as a trial assistance for code reading that has not been underestimated, although it is very important in studies of programming. In the statement fill-in-blank problem, a student is requested to fill a statement to the blank in a given Java code. By using a Program Dependence Graph (PDG), this function blanks an essential statement in the code. To evaluate our proposal, we generated multiple statement fill-in-blank problems using codes with similar procedures and applied them to students in a Java programming course in our department. Then, we found that the solution time of students decreased as they solved more problems.

    CiNii Article

    CiNii Books

    researchmap

  • A Difficulty Estimation Method of Fill-in-blank Problems for Java Programming Learning Assistant System

    OGAWA Takuya, FUNABIKI Nobuo, NAKANISHI Toru, ISHIHARA Nobuya, NA Ta, AMANO Noriki

    IEICE technical report. Education technology   113 ( 482 )   41 - 46   2014.3

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    In our group, we have proposed a Web-based Java Programing Learning Assistant System (JPLAS) that helps students to study Java programing by themselves and the reduction of the burden on teacher. JPLAS has two kinds of blanks supplement (element fill-in-blank problem, statement fill-in-blank problem). These problems are applied to a student as a self-study problem in the classes of this school for Java programming abecedarians. In this thesis, after having enumerated indexes to estimate the difficulty of the problem that a teacher generated in JPLAS, we propose the index suitable for the difficulty estimate of each problem by performing the correlation analysis with the correct answer rate of each problem by the self-study result. We enable the presentation of the problem that a teacher accepted the level of the student by implementing difficulty estimation method of each fill-in-blank problem in JPLAS.

    CiNii Article

    CiNii Books

    researchmap

  • An Extension of Active Access Point Selection Algorithm Considering Practical Conditions for Wireless Mesh Networks

    FUJITA Sho, FUNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report. Circuits and systems   113 ( 463 )   35 - 40   2014.3

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    The wireless Internet-access mesh network (WIMNET) can realize an inexpensive flexible Internet-access network by using multiple access points (APs) connected by wireless links. For WIMNET with a single Internet Gateway (GW), we have proposed the active AP selection algorithm of selecting active APs from redundantly allocated APs for communications. However, in practical implementations of WIMNET, multiple GWs usually exist and the number of hops between a GW and a host is limited. Furthermore, the communication speed is dynamically changed by the link distance for the new high-speed communication protocol IEEE802.11ac. In this paper, we propose an extension of the active AP selection algorithm to consider these conditions. We verify the effectiveness of our proposal through simulations in four instances using the WIMNET simulator.

    CiNii Article

    CiNii Books

    researchmap

  • File Synchronization Performance using Bittorrent Sync in IEEE802.11ac Wireless Networks

    KIM Bongsu, FUNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report. Circuits and systems   113 ( 463 )   29 - 34   2014.3

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Recently, Bittorrent Inc. has released a file synchronization software called Bittorrent Sync based on the peer-to-peer file sharing software Bittorrent. Using this software, users can synchronize the files on the designated folders across the multiple devices that are connected through the Internet without using a management server. These devices can be personal computers, smart phones, and tablets using different operating systems. To identify the folders to be synchronized, this software uses a 20-byte secret key that is randomly generated. We have considered the use of Bittorrent Sync to share files among nodes in a large wireless local area network (WLAN), where some nodes may be connected through mulithop wireless links. In this paper, we set up a simple WLAN test bed using the IEEE 802.1 lac protocol that has been recently introduced as a high-speed wireless communication protocol, and measure throughputs when various files with different sizes are synchronized among nodes using the software. Our results show that the throughput is quite high and stable, and a larger file can be transferred in a higher speed than a smaller file.

    CiNii Article

    CiNii Books

    researchmap

  • An Extension of Wireless Internet-Access Mesh Network Simulator for Frame Aggregation

    TAJIMA Shigeto, FUNABIKI Nobuo, HIGASHINO Teruo

    IEICE technical report. Circuits and systems   113 ( 463 )   103 - 108   2014.3

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    The Wireless Internet-access Mesh NETwork (WIMNET) can provide an inexpensive, flexible, and expandable Internet-access network by connecting multiple access-points (APs) through wireless links. To improve the performance of WIMNET, it is important to adopt high-speed wireless communication protocols IEEE 802.11n/ac that have recently become available, for heavily crowded links between APs. As one of the technologies to enhance the communication speed, the frame aggregation has been introduced so that multiple frames can be sent at the same time to reduce the communication overhead. Because each link between APs usually handles packets to/from multiple hosts in WIMNET, the effect of the frame aggregation can be further enhanced. In this paper, we present a model of the frame aggregation and an extension of the WIMNET simulator based on the model, which has been developed by our group to evaluate the performance of WIMNET. Through simulations in simple topologies, we show the effectiveness of the frame aggregation, and the necessity of the proper number of aggregated frames and the aggregated routing path.

    CiNii Article

    CiNii Books

    researchmap

  • Throughput Measurements Using IEEE 802.11ac Devices for High-Speed Wireless Networks

    CHEW Chang Choon, FUNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report. Circuits and systems   113 ( 463 )   23 - 28   2014.3

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Recently, IEEE802.11ac communication protocols have been introduced for high-speed wireless networks. Then, commercial devices implementing this protocol have been available from several vendors. In this paper, we provide various TCP throughput measurement results using devices from three vendors implementing this protocol under a set of TCP parameters in various conditions including one or two-hop communications, wall obstacle existences, different link distances, and the use of a repeater. Our measurement results show that TCP throughputs are greatly affected by vendors and communication conditions.

    CiNii Article

    CiNii Books

    researchmap

  • An Implementation of Moblie Anonymous Attribute Authentication System on Android Devices

    IPSJ SIG Notes   2014 ( 45 )   1 - 6   2014.2

     More details

    Language:Japanese   Publisher:Information Processing Society of Japan (IPSJ)  

    In current ID-based authentication systems, service providers can collect user's history via user's ID. On the other hand, service providers often want to authenticate user's attributes. To solve this problem, an anonymous attribute authentication system was proposed, where the user's attribtes are autheticated without revealing any information that can speciy the user. In this paper, we implemented a mobile anonymous attribute system using NFC and Bluetooth, where, by bringing the device close to another one, we can perform a direct anonymous attribute authentication. From the experiments on real devices, the execution time of anonymous attribute authentication is 0.98 seconds, and the total processing time including the connection establishment is 1.85 seconds.

    CiNii Article

    CiNii Books

    researchmap

  • A proposal of Web Browser-based Volunteer Computing Platform

    Shogo Takaki, Kan Watanabe, Masaru Fukushi, Noriki Amano, Nobuo Funabiki, Toru Nakanishi

    IPSJ SIG Notes   2014 ( 29 )   1 - 8   2014.2

     More details

    Language:Japanese   Publisher:Information Processing Society of Japan (IPSJ)  

    In Volunteer Computing (VC) systems, volunteer participants can contribute their idle computing resources by computing a piece of the computation (job) in their idle time. In existing VC systems, participants must put an extra effort, e.g. installing a dedicated software to their computers and register their personal E-mail addresses, which will be barriers to join as a participant. This paper proposes a web-based VC platform, in which participants can join to VC system by just accessing a specified URL with Web browsers. By using LLVM techniques such as PNaCL, VC jobs become convertible as fast-acting Web applications. As the results of our experiments based on Himeno Benchmark, we show that the performance of PNaCl codes on a web browser is equivalent of native one.

    CiNii Article

    CiNii Books

    researchmap

  • A Web Recipe Conversion Algorithm for Cooking-Step Scheduling

    ZHANG Yijia, FUNABIKI Nobuo, NAKANISHI Toru

    Technical report of IEICE. SS   113 ( 422 )   11 - 16   2014.1

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Previously, we have proposed the cooking-step scheduling algorithm to assist home-made cooking by busy people such as working persons and students. When a cooking-step schedule of applying the cooking procedures in recipes in a Web site is generated by this algorithm, their conversion into the unique input form to the algorithm is required. In this paper, we propose a Web-recipe conversion algorithm that converts cooking procedures in a recipe into six types of cooking-steps and estimates the corresponding cooking time by extracting keywords in the recipe that correspond to the cooking-step types. We verified the effectiveness of the proposed algorithm through applying it to 100 recipes.

    CiNii Article

    CiNii Books

    researchmap

  • A Clue Function Using Javadoc for Code Writing Problem in Java Programming Learning Assistant System

    NAKAMURA Takuya, FUNABIKI Nobuo, NAKANISHI Toru, AMANO Noriki

    IEICE technical report. Education technology   113 ( 377 )   115 - 120   2014.1

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Java has been educated in a lot of universities and professional schools due to the reliability, portability, and easy learning. To assist Java educations, our group has developed a Web-based Java Programming Learning Assistant System (JPLAS) that helps students to study Java programming by themselves through automatic testing of Java codes from students using the test-driven development method. Unfortunately, JPLAS is not suitable for less-experienced students in Java because they have to understand test codes that are necessary in automatic testing before writing source codes. In this paper, we propose a Javadoc-based hint function in the code design learning function of JPLAS to let such students learn how to collect the necessary information for a source code from a test code easily. It helps students to understand the whole structure of the source code and complete more accurate code design. We verify the effectiveness of our proposal through applications to 10 students in our laboratory.

    CiNii Article

    CiNii Books

    researchmap

  • Implementation of Anonymous Credential System with Efficient Proofs for Monotone Formulas on Attributes Excluding Restriction

    Shahidatul Sadiah, Toru Nakanishi, Nobuo Funabiki

    2014 SECOND INTERNATIONAL SYMPOSIUM ON COMPUTING AND NETWORKING (CANDAR)   531 - 535   2014

     More details

    Language:English   Publisher:IEEE  

    An anonymous credential system allows a user to convince a service provider anonymously that he/she owns certified attributes. Previously, we proposed an anonymous credential system to prove user's attributes to satisfy a monotone formula, i.e., a logic relation with any combination of AND/OR relations. However, this system has a restriction that the user can prove the monotone formula when only one attribute is true for any OR relation. Recently, we proposed the improved system to overcome the restriction, by adopting Linear Homonorphic (LH) signature scheme to generate a certificate that contains the minimum attribute set as required in the verification. However, the improved system has never been implemented, and thus the practicality is not evaluated. In this paper, we implement the system using a fast pairing library, and measure the processing times and data sizes, when changing the number of user's attributes and the size of the proved relation.

    DOI: 10.1109/CANDAR.2014.35

    Web of Science

    researchmap

  • A Proposal of Routing Algorithm under Practical Conditions for Wireless Internet-Access Mesh Networks

    Nobuo Funabiki, Toru Nakanishi, Wataru Maruyama

    2014 IEEE INTERNATIONAL CONFERENCE ON CONSUMER ELECTRONICS - TAIWAN (ICCE-TW)   27 - 28   2014

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    A Wireless Internet-access Mesh NETwork (WIMNET) can provide an expandable Internet-access network by flexibly adopting multiple Access-Points (APs) that have wireless connections in the field. Previously, we proposed a routing algorithm for generating an optimal routing path between the hosts and one Internet Gateway (GW). However, in practical situations, multiple GWs are usually necessary for scalability. Beside, in the high-speed IEEE802.11ac protocol, the link speed drastically decreases as the distance increases due to the lowered receiving signal quality. Furthermore, commercial APs implementing them have the limitation on the number of hops between a GW and a host. In this paper, we propose a routing algorithm to consider these practical conditions for large-scale WIMNET. We verify the effectiveness through simulating three topologies using the WIMNET simulator.

    DOI: 10.1109/ICCE-TW.2014.6904085

    Web of Science

    researchmap

  • Extensions of Active Access-Point Selection Algorithm for Wireless Mesh Networks Using IEEE802.11ac Protocol

    Chang Choon Chew, Nobuo Funabiki, Sho Fujita

    2014 SECOND INTERNATIONAL SYMPOSIUM ON COMPUTING AND NETWORKING (CANDAR)   310 - 314   2014

     More details

    Language:English   Publisher:IEEE  

    A wireless Internet-access mesh network (WIMNET) provides a scalable Internet-access network by flexibly allocating access points (APs) in the field that are connected by wireless links. Previously, we proposed an active AP selection algorithm to select the APs to be activated among the redundantly allocated APs for WIMNET that has a single Internet gateway (GW). However, in practical implementations of large-scale WIMNET, multiple GWs are usually necessary to increase the capacity of Internet connections. Besides, the number of hops between a GW and a host is limited for stable multihop communications, and the transmission speed of a wireless link is dynamically changed by the link condition such as the distance in the high-speed IEEE802.11ac protocol. Furthermore, the minimum throughput should be provided to a host as QoS (Quality of Service) when it is exclusively connected with the GW. In this paper, we propose extensions of the active AP selection algorithm to consider these conditions. We verify the effectiveness of our proposal through simulations in three topologies using the WIMNET simulator.

    DOI: 10.1109/CANDAR.2014.29

    Web of Science

    researchmap

  • A Frame Aggregation Extension of Routing Algorithm for Wireless Mesh Networks

    Nobuo Funabiki, Yuuma Tani, Shigeto Tajima

    2014 SECOND INTERNATIONAL SYMPOSIUM ON COMPUTING AND NETWORKING (CANDAR)   238 - 242   2014

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    As a scalable Internet-access network, an Wireless Internet-access Mesh NETwork (WIMNET) consists of multiple wireless access-points (APs) that are connected through wireless links. At least one AP acts as a gateway (GW) to the Internet where any host must reach there through multi-hop communications between APs. To handle large traffics, the latest highspeed IEEE 802.11ac protocol should be adopted for scalable WIMNET, where the routing path determines the performance under its practical implementations using commercial products. Therefore, we have proposed a routing algorithm considering 1) multiple GWs, 2) the link speed change, and 3) the limited number of hops. In this paper, to further improve the performance, we extend the routing algorithm to efficiently consider the frame aggregation in IEEE802.11ac. We verify the effectiveness of our proposal through simulating two topologies using the extended WIMNET simulator.

    DOI: 10.1109/CANDAR.2014.28

    Web of Science

    researchmap

  • An extended active access-point selection algorithm for link speed changes in wireless mesh networks

    International Journal Space-Based and Situated Computing   4 ( 3 )   184 - 193   2014

     More details

    Language:English  

    researchmap

  • A Proposal of Javadoc Hint Function for Java Programming Learning Assistant System

    Nobuo Funabiki, Takuya Nakamura, Wen-Chung Kao

    2014 IEEE 3RD GLOBAL CONFERENCE ON CONSUMER ELECTRONICS (GCCE)   304 - 308   2014

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    As a reliable, portable, and practical programming language, Java has been educated in many universities and professional schools. To assist Java educations, we have developed a Web-based Java Programming Learning Assistant System (JPLAS) to help students studying Java programming by themselves through automatic testing of Java source codes using the test-driven development (TDD) method. Unfortunately, JPLAS is not suitable for novice students taking basic Java classes, because they need to extract necessary information such as the names of classes and methods from a test code for automatic testing before writing a source code. Previously, we implemented the code design learning function in JPLAS to assist such students. In this paper, we propose a Javadoc hint function in JPLAS to further assist students by showing the detailed information that is automatically generated from the reference code by a teacher for the assignment. We verify the effectiveness of our proposal through an experimental use by 41 students in our department.

    DOI: 10.1109/GCCE.2014.7031127

    Web of Science

    researchmap

  • An Extension of Access-Point Allocation Algorithm for Adapting Link Speed Change in Wireless Mesh Network

    FARAG Tamer, FUNABIKI Nobuo, HASSAN Walaa

    IEICE technical report   113 ( 360 )   137 - 142   2013.12

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As an inexpensive, scalable Internet-access wireless network, we have studied design optimizations of the Wireless Internet-access Mesh NETwork (WIMNET). WIMNET uses multiple access-points (APs) that are connected by wireless links. In WIMNET, the proper allocation of APs is essential to ensure the communication quality of hosts and to minimize the installation and management cost. Previously, we have proposed an AP allocation algorithm for WIMNET assuming that every link has a constant speed regardless of the condition. However, our preliminary experiments found that the link speed is greatly affected by the distance and interferences in high-speed IEEE802.11n/ac protocols that have recently become popular. In this paper, we propose an extension of our AP allocation algorithm to adapt to this link speed change where the maximum link distance between two APs that has been fixed in the previous algorithm is optimized to provide the highest performance. We verify the effectiveness of our extended algorithm through simulations in simple topology instances using the WIMNET simulator.

    CiNii Article

    CiNii Books

    researchmap

  • A Proposal of Routing Tree Algorithm for Scalable Wireless Mesh Networks Under Practical Conditions

    MARUYAMA Wataru, FUNABIKI Nobuo, NAKANISHI Toru

    Technical report of IEICE. RCS   113 ( 361 )   249 - 254   2013.12

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As a flexible cost-efficient Internet access network, we have studied the Wireless Internet-access Mesh NETwork (WIMNET) that is composed of multiple access points (APs) connected through wireless links. We have proposed a routing tree algorithm to find a routing path between one Internet gateway (GW) and the hosts. However, normally, several GWs exist in practical implementations of WIMNET. The number of hops between a GW and a host is limited for commercial APs. Furthermore, the communication speed is dynamically changed by the link distance for the new high-speed communication protocol IEEE802.11ac. In this study, we propose a new routing tree algorithm considering these conditions for WIMNET. We verify the effectiveness of our proposal through simulating two instances using the WIMNET simulator.

    CiNii Article

    CiNii Books

    researchmap

  • An Extension of Access-Point Allocation Algorithm for Adapting Link Speed Change in Wireless Mesh Network

    FARAG Tamer, FUNABIKI Nobuo, HASSAN Walaa

    Technical report of IEICE. RCS   113 ( 361 )   255 - 260   2013.12

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As an inexpensive, scalable Internet-access wireless network, we have studied design optimizations of the Wireless Internet-access Mesh NETwork (WIMNET). WIMNET uses multiple access-points (APs) that are connected by wireless links. In WIMNET, the proper allocation of APs is essential to ensure the communication quality of hosts and to minimize the installation and management cost. Previously, we have proposed an AP allocation algorithm for WIMNET assuming that every link has a constant speed regardless of the condition. However, our preliminary experiments found that the link speed is greatly affected by the distance and interferences in high-speed IEEE802.11n/ac protocols that have recently become popular. In this paper, we propose an extension of our AP allocation algorithm to adapt to this link speed change where the maximum link distance between two APs that has been fixed in the previous algorithm is optimized to provide the highest performance. We verify the effectiveness of our extended algorithm through simulations in simple topology instances using the WIMNET simulator.

    CiNii Article

    CiNii Books

    researchmap

  • Evaluation and Improvement of Credibility-based Voting for Volunteer Computing Systems with Dynamic Error Rate

    2013 ( 26 )   1 - 8   2013.12

     More details

  • An Implementation of Volunteer Computing System with Credibility-based voting

    2013 ( 19 )   1 - 7   2013.12

     More details

  • Efficient Proofs for CNF Formulas on Attributes in Pairing-Based Anonymous Credential System

    Nasima Begum, Toru Nakanishi, Nobuo Funabiki

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E96A ( 12 )   2422 - 2433   2013.12

     More details

    Language:English   Publisher:IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

    To enhance user privacy, anonymous credential systems allow the user to convince a verifier of the possession of a certificate issued by the issuing authority anonymously. In the systems, the user can prove relations on his/her attributes embedded into the certificate. Previously, a pairing-based anonymous credential system with constant-size proofs in the number of attributes of the user was proposed. This system supports the proofs of the inner product relations on attributes, and thus can handle the complex logical relations on attributes as the CNF and DNF formulas. However this system suffers from the computational cost: The proof generation needs exponentiations depending on the number of the literals in OR relations. In this paper, we propose a pairing-based anonymous credential system with the constant-size proofs for CNF formulas and the more efficient proof generation. In the proposed system, the proof generation needs only multiplications depending on the number of literals, and thus it is more efficient than the previously proposed system. The key of our construction is to use an extended accumulator, by which we can verify that multiple attributes are included in multiple sets, all at once. This leads to the verification of CNF formulas on attributes. Since the accumulator is mainly calculated by multiplications, we achieve the better computational costs.

    DOI: 10.1587/transfun.E96.A.2422

    Web of Science

    researchmap

  • A Proposal of Extended Anonymous Credential Scheme with Efficient Proof of Age Inequality (Information Security)

    SADIAH Shahidatul, NAKANISHI Toru, WATANABE Kan, FUNABIKI Nobuo

    Technical report of IEICE. ISEC   113 ( 217 )   21 - 28   2013.9

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    An anonymous credential system on attributes allows a user to convince a service provider anonymously that he/she owns a certified attribute. Previously, an anonymous credential system to prove that user attributes satisfy a CNF formula on attributes was proposed. However, the system needs a large public key (PK) size and thus the large computation times, when proving the age in equation using the birthday attribute, because each birthday is assigned to one attribute and each attribute is mapped to one public parameter. In this paper, to reduce the PK size and computation times, we use the idea of dividing the birthday (year/month/day) attribute into the year, the month, and the day attributes. Consequently, the PK size is decreased, since the number of attributes is reduced to approximately 0.3%. In case of proving the age in equation, these attributes have to be expressed using monotone logic formulas. To adopt this idea on previous system, we extend the accumulator in the previous system and we propose an anonymous credential system to prove monotonic formulas. Also, we show the effectiveness of proposed system by measuring the process times for the implementation.

    CiNii Article

    CiNii Books

    researchmap

  • A Clustering Algorithm Considering Link Speed for Wireless Mesh Networks

    TAJIMA Shigeto, FUNABIKI Nobuo, HIGASHINO Teruo

    IEICE technical report   113 ( 129 )   155 - 160   2013.7

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    A Wireless Internet-access Mesh Network (WIMNET) can provide a scalable Internet-access network by using multiple access point (APs) connected through wireless communications. In previous studies, we proposed a clustering algorithm for efficiently composing large scale WIMNET by partitioning the APs into a set of clusters. For this algorithm, we assume that any link has a constant speed, although our preliminary experiments found that the link speed is greatly changed by the link distance and interferences for the new high-speed IEEE802.11n protocol that has recently become popular. In this paper, we extend the clustering algorithm in considering the link speed change for effectively introducing IEEE802.11n to WIMNET. We verify the effectiveness of our proposal through simulations in grid topology instances using the WIMNET simulator.

    CiNii Article

    CiNii Books

    researchmap

  • A Fixed Backoff-Time Switching Method for CSMA/CA Protocol in Wireless Mesh Networks

    Sritrusta Sukaridhoto, Nobuo Funabiki, Toru Nakanishi, Kan Watanabe, Shigeto Tajima

    IEICE TRANSACTIONS ON COMMUNICATIONS   E96B ( 4 )   1019 - 1029   2013.4

     More details

    Language:English   Publisher:IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

    As a flexible and cost-efficient scalable Internet access network, we studied architectures, protocols, and design optimizations of the Wireless Internet-access Mesh NETwork (WIMNET). WIMNET is composed of multiple access points (APs) connected through multihop wireless communications on IEEE 802.11 standards. The increasing popularity of real-time applications such as IF-phones and IP-TV means that they should be supported in WIMNET. However, the contention resolution mechanism using a random backoff-time in the CSMA/CA protocol of 802.11 standards is not sufficient for handling real-time traffic in multihop wireless communications. In this paper, we propose a Fixed Backoff-time Switching (FBS) method for the CSMA/CA protocol to improve the real-time traffic performance in WIMNET by giving the necessary activation chances to each link. We implement our proposal on the QualNet simulator, and verify its effectiveness through simulations on three network topologies with four scenarios.

    DOI: 10.1587/transcom.E96.B.1019

    Web of Science

    researchmap

  • BS-1-26 A Design for OpenFlow lmplementation of Fixed Backoff-time Switching Method in Wireless Mesh Networks

    Sukaridhoto Sritrusta, Funabiki Nobuo, Nakanishi Toru, Watanabe Kan

    Proceedings of the IEICE General Conference   2013 ( 2 )   "S - 50"-"S-51"   2013.3

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    CiNii Article

    CiNii Books

    researchmap

  • BS-1-2 AN IMPROVED HOST ASSOCIATION OPTIMIZATION STAGE IN ACCESS-POINT AGGREGATION ALGORITHM FOR WIRELESS LOCAL AREA NETWORKS

    Islam Ezharul, Funabiki Nobuo, Nakanishi Toru, Watanabe Kan

    Proceedings of the IEICE General Conference   2013 ( 2 )   "S - 3"-"S-4"   2013.3

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    CiNii Article

    CiNii Books

    researchmap

  • D-9-7 A Proposal of Web-based Receipt Information Management System

    na Ta, Funabiki Nobuo, Nakanishi Toru, Watanabe Kan

    Proceedings of the IEICE General Conference   2013 ( 1 )   105 - 105   2013.3

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    CiNii Article

    CiNii Books

    researchmap

  • D-9-27 AN EXPERIMENTAL EVALUATION OF COOKING-STEP SCHEDULING ALGORITHM IN COOKING FOUR DISHES

    Matsushima Yukiko, Okada Tomoya, Funabiki Nobuo, Nakanishi Toru, Watanabe Kan

    Proceedings of the IEICE General Conference   2013 ( 1 )   125 - 125   2013.3

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    CiNii Article

    CiNii Books

    researchmap

  • An Extension of Routing Tree Algorithm Considering Link Speed Change for Wireless Mesh Networks

    MARUYAMA Wataru, FUNABIKI Nobuo, NAKANISHI Toru, WATANABE Kan

    IEICE technical report   112 ( 392 )   1 - 6   2013.1

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As a flexible inexpensive Internet-access network, we have studied the Wireless Internet-access Mesh NETwork (WIMNET) that is composed of wirelessly interconnected Access-Points (APs). Previously, we proposed the routing tree algorithm to generate a routing path connecting the APs in WIMNET such that the performance can improved by reducing congestions at links around the Internet Gate Way (GW). For this algorithm, we assume that every link has the same constant speed to transmit data packets regardless of its distance However, when we adopt the new high-speed IEEE802. 11n protocol for wireless communications, our preliminary experiments found that the speed decreases drastically as the distance increases. In this paper, we extend the routing tree algorithm in order to consider the link speed change and generate the routing path to the hosts. We show the effectiveness of this extension through simulations in three instances.

    CiNii Article

    CiNii Books

    researchmap

  • An Extension of Access-Point Aggregation Algorithm Considering Link Speed Change for Wireless Local Area Networks

    ISLAM Md. EZHARUL, FUNABIKI Nobuo, NAKANISHI Toru, WATANABE Kan

    IEICE technical report   112 ( 392 )   7 - 12   2013.1

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    These days, multiple wireless local area networks (WLANs) have been often deployed in the same building of a university or a company. In those WLANs, access points (APs) are usually managed independently by different groups such as laboratories or departments. Then, a host can detect signals from multiple APs, which may degrade the communication performance due to their interferences and increase the operational cost Previously, we have proposed an AP aggregation algorithm to minimize the number of active APs in the field by aggregating them using the virtual AP technology. Recently, the IEEE802. 11n protocol has become popular as a high-speed communication protocol for WLANs However, our preliminary experiments using this protocol found that the link speed drastically decreases as its distance increases. In this paper, we extend our AP aggregation algorithm to considering this speed change so that any host can ensure the minimum speed with an AP while maximizing the overall throughput of the network. We verify the effectiveness of our extension through simulations in a network scenario using the WIMNET simulator.

    CiNii Article

    CiNii Books

    researchmap

  • An Extension of Active Access Point Selection Algorithm for Wireless Mesh Networks

    FUJITA Sho, FUNABIKI Nobuo, NAKANISHI Tom, WATANABE Kan

    IEICE technical report   112 ( 392 )   19 - 24   2013.1

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    The wireless Internet-access mesh network (WIMNET) has been studied to realize an inexpensive, scalable Inter-net-access network by using multiple access points (APs) connected by wireless links. WIMNET can improve the dependability to failures of links and APs by allocating APs redundantly. Since redundant APs may cause the increase of the operational cost and the degradation of the throughput due to increasing radio interferences, we have proposed the active AP selection algorithm for selecting functioning APs for communications. In this algorithm, we assume that every link speed is constant for simplicity, although our preliminary expenments found that the link speed greatly is affected by the distance in the new high-speed IEEE802.11 n protocol that has recently become popular. In this paper, we extend the active AP selection algonthm in considering this link speed change. We verify the effectiveness of our proposal through simulations in four instances using the WIMNET simulator.

    CiNii Article

    CiNii Books

    researchmap

  • Database Design and Input Data Processing Algorithm for Receipt Information System

    Tana, FUNABIKI Nobuo, NAKANISHI Toru, WATANABE Kan

    IEICE technical report. Life intelligence and office information systems   112 ( 379 )   85 - 90   2013.1

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Recently, due to the lasting economic depression, an economical life has been desired for many people. For their assistance, our group is developing a Web-based receipt information system to help keeping household accounts to grasp daily expenses, and sharing latest information of selling products at nearby shops to buy products as inexpensively as possible. In this paper, we present the database design for this system, and propose the input data processing algorithm composed of the functions for 1) product name corrections, 2) discount price corrections, and 3) category classifications, to solve problems in the character recognition software on receipts adopted in this system. Our preliminary experiments found that this software often falsely recognizes product names, cannot correct discount prices, and cannot automatically classify categories of products. We implemented the proposed algorithm as a Java application, and applied it to 113 products from 12 receipts where every product was correctly processed.

    CiNii Article

    CiNii Books

    researchmap

  • An Android Application of Cooking Guidance Function in Homemade Cooking Assistance System

    OKADA Tomoya, MATSUSHIMA Yukiko, FUNABIKI Nobuo, NAKANISHI Toru, WATANABE Kan

    IEICE technical report. Information and communication management   112 ( 378 )   91 - 96   2013.1

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    In order to assist economical and healthy lives with homemade cooking, our group has developed a Web-based HOmemade Cooking Assistance System (HOCAS) Previously, we have implemented the menu planning function and the cooking-step scheduling function at the server, so that busy persons such as working people, students, and nurturing families can make menus and cooking-step schedules for one week including bulk cooking in weekends. In this paper, we implement the cooking guidance function as an Android application of cooking guidance. Using outputs of the existing functions, it provides the three functions for the menu indication, the cooking guidance, and the cooking time measurement. For experimental evaluations, we cooked four dishes by following the guidance from the system, and confirmed its effectiveness. Through comparing cooking times between expected and measured ones, we analyzed its problems and discussed future works.

    CiNii Article

    CiNii Books

    researchmap

  • An Android Application of Cooking Guidance Function in Homemade Cooking Assistance System

    OKADA Tomoya, MATSUSHIMA Yukiko, FUNABIKI Nobuo, NAKANISHI Toru, WATANABE Kan

    IEICE technical report. Life intelligence and office information systems   112 ( 379 )   91 - 96   2013.1

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    In order to assist economical and healthy lives with homemade cooking, our group has developed a Web-based HOmemade Cooking Assistance System (HOCAS) Previously, we have implemented the menu planning function and the cooking-step scheduling function at the server, so that busy persons such as working people, students, and nurturing families can make menus and cooking-step schedules for one week including bulk cooking in weekends. In this paper, we implement the cooking guidance function as an Android application of cooking guidance. Using outputs of the existing functions, it provides the three functions for the menu indication, the cooking guidance, and the cooking time measurement. For experimental evaluations, we cooked four dishes by following the guidance from the system, and confirmed its effectiveness. Through comparing cooking times between expected and measured ones, we analyzed its problems and discussed future works.

    CiNii Article

    CiNii Books

    researchmap

  • An Extension of Fill-in-the-blank Problem Function in Java Programming Learning Assistant System and Its Application to Classes

    KORENAGA Yousuke, FUNABIKI Nobuo, NAKANISHI Toru, WATANABE Kan, AMANO Noriki

    IEICE technical report. Education technology   112 ( 374 )   63 - 68   2013.1

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Nowadays, a programming language Java has been educated in many universities and professional schools To assist its self-studies by students, we have developed a Web-based Java Programming Learning Assis-tant System (JPLAS) In this work, we extend the fill-in-the-blank problem functcon in JPLAS, so that this function can select variables and grammar symbols into problems in addition to conventional reserved words This function can automatically generate fill-in-the-blank problems by randomly blanking symbols in a sample Java code that correspond to the words specified by a teacher, where the constraints for unique answers are observed For evalu-ations of this function, we applied it to students in a Java programming course in our department after preparing 100 problems with various levels using JPLAS Then, we assigned them a quiz of the related problems to verify the learning effect The result shows that those who solved more problems in JPLAS could obtain better scores in the quiz

    CiNii Article

    CiNii Books

    researchmap

  • A Java programming learning assistant system using test-driven development method

    Nobuo Funabiki, Yukiko Matsushima, Toru Nakanishi, Kan Watanabe, Noriki Amano

    IAENG International Journal of Computer Science   40 ( 1 )   38 - 46   2013

     More details

    Authorship:Lead author   Language:English  

    researchmap

  • An Extension of Access-Point Aggregation Algorithm to Ensure Minimum Host Throughput for Wireless Local Area Networks

    Md. Ezharul Islam, Nobuo Funabiki, Toru Nakanishi, Kan Watanabe

    2013 FIRST INTERNATIONAL SYMPOSIUM ON COMPUTING AND NETWORKING (CANDAR)   141 - 147   2013

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    Recently, many organizations such as universities and companies are deploying multiple wireless local area networks (WLANs) even in the same building. In these WLANs, wireless access-points (APs) are usually managed independently by different groups such as laboratories or departments. In this overlapped WLAN environment, a host can detect signals from multiple APs, which may degrade the communication performance due to their interferences and increase the operational cost. To solve this problem, previously, we have proposed the AP aggregation algorithm to minimize the number of active APs in the field by aggregating them using the virtual AP technology. However, the minimization of active APs may excessively degrade the performance of WLANs, where more active APs can usually increase it. In this paper, we propose an extension of the AP aggregation algorithm to ensure the minimum average throughput for each host in the field. This average throughput is estimated using the cost function defined in the algorithm, and the number of active APs is increased when it does not reach the given threshold. We verify the effectiveness of this extension through extensive simulations in two network instances using the WIMNET simulator.

    DOI: 10.1109/CANDAR.2013.27

    Web of Science

    researchmap

  • An improvement of graph-based fill-in-blank problem generation algorithm in Java programming learning assistant system

    Tana, Nobuo Funabiki, Toru Nakanishi, Noriki Amano

    International Workshop on ICT   1 - 4   2013

     More details

    Language:English  

    researchmap

  • A cooking guidance function on Android tablet for Homemade Cooking Assistance System

    Yukiko Matsushima, Nobuo Funabiki, Tomoya Okada, Toru Nakanishi, Kan Watanabe

    2013 IEEE Region 10 Humanitarian Technology Conference, R10-HTC 2013   249 - 254   2013

     More details

    Language:English  

    To assist busy people such as working persons, students, and nurturing families to have economical and healthy lives with homemade cooking, we have proposed a Web-based HOmemade Cooking Assistance System (HOCAS). Previously, we implemented the menu planning function and the cooking-step scheduling function at the server using JSP/Servlet, so that a user can plan a menu for the whole week and make a cooking-step schedule to efficiently cook multiple dishes at the same time. Unfortunately, a user needs to refer the next cooking-step on a paper during cooking process, which is actually not easy at critical timing in a kitchen, because the schedule is output as a PDF file. In this paper, we propose a cooking guidance function on an Android tablet as a Java application to navigate cooking-steps through touch panel operations. We confirmed the effectiveness by experimentally cooking four dishes using this function. © 2013 IEEE.

    DOI: 10.1109/R10-HTC.2013.6669050

    Scopus

    researchmap

  • An extension of fill-in-the-blank problem function in Java programming learning assistant system

    Nobuo Funabiki, Yousuke Korenaga, Toru Nakanishi, Kan Watanabe

    2013 IEEE Region 10 Humanitarian Technology Conference, R10-HTC 2013   85 - 90   2013

     More details

    Authorship:Lead author   Language:English  

    Nowadays Java has been educated in many universities and professional schools as a reliable, portable, and practical programming language. To assist self-studies by students, we have developed a Web-based Java Programming Learning Assistant System (JPLAS). JPLAS has the two main functions of code writing problem and fill-in-the-blank problem to support studies at different levels. The former function intends that a student can write a whole code from scratch, where the submitted code is automatically tested on the server using the test-driven development (TDD) method. The latter function intends that a novice student can study Java reserved words, where a problem is generated by randomly removing the specified ones from a selected sample code and the removed one becomes the correct answer to each blank. In this paper, we extend this latter function for removing more general elements including variables and control symbols in problems. We analyze the conditions for selecting blanked elements with unique correct answers. For evaluations, we generated 100 problems with various levels using the extended function, and assigned them to students in the Java programming course in our department. Then, we gave a short test and a questionnaire with nine questions, where we found that students solving more problems achieved better scores in general, and their opinions support the effectiveness of our proposal. © 2013 IEEE.

    DOI: 10.1109/R10-HTC.2013.6669019

    Scopus

    researchmap

  • A Modified Active Access-Point Selection Algorithm Considering Link Speed Change in IEEE 802.11n for Wireless Mesh Networks

    Nobuo Funabiki, Sho Fujita, Toru Nakanishi, Kan Watanabe

    2013 SEVENTH INTERNATIONAL CONFERENCE ON COMPLEX, INTELLIGENT, AND SOFTWARE INTENSIVE SYSTEMS (CISIS)   714 - 719   2013

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    As an inexpensive, scalable Internet-access wireless network, we have studied the architecture, protocols, and design optimizations of the wireless Internet-access mesh network (WIMNET) that uses multiple access-points (APs) connected by wireless links. WIMNET can improve the dependability to failures of links and/or APs by allocating APs redundantly in the network field. Because redundant APs can increase the operational cost and degrade the performance due to increasing radio interferences, only the necessary APs for connections between the hosts and the Internet gateway should be activated at communications. Previously, we have defined the active AP selection problem of selecting the minimum number of active APs, and proposed its heuristic algorithm, assuming that every link has the same constant speed for simplicity. However, our preliminary experiments found that the link speed is greatly affected by the distance in the high-speed IEEE802.11n protocol that has recently become popular. In this paper, we propose a modification of the active AP selection algorithm to consider the link speed change, where we introduce a new design parameter for WIMNET to select links that have sufficient throughputs. We verify the effectiveness of our modified algorithm through simulations in four instances using the WIMNET simulator.

    DOI: 10.1109/CISIS.2013.128

    Web of Science

    researchmap

  • A Modified Routing Tree Algorithm Considering Link Speed Change in IEEE 802.11n for Wireless Mesh Network

    Nobuo Funabiki, Toru Nakanishi, Kan Watanabe, Wataru Maruyama

    2013 IEEE 17TH INTERNATIONAL SYMPOSIUM ON CONSUMER ELECTRONICS (ISCE)   29 - 30   2013

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    A Wireless Internet-access Mesh NETwork (WIMNET) can provide an expandable Internet-access network by adopting multiple Access-Points (APs) that have wireless connections with each other. Previously, we proposed a routing tree algorithm for generating an optimal routing path between the APs and the Internet Gate Way (GW) with a minimal transmission delay, assuming that every link has the same data transmission speed. However, our preliminary experiments found that the link speed using the IEEE802.11n as a new high-speed protocol for wireless communications, decreases drastically as the distance increases due to the lowered receiving signal quality. In this paper, we propose a modified routing tree algorithm to consider the large speed change in order to adopt the IEEE 802.11n in WIMNET effectively. In addition to links between APs, our modified algorithm selects the links between hosts and their associated APs. We verify the effectiveness of the modified algorithm through simulations in three topologies.

    DOI: 10.1109/ISCE.2013.6570233

    Web of Science

    researchmap

  • Reducing public-key size in an anonymous credential system for CNF formulas with constant-size proofs

    Nasima Begum, Toru Nakanishi, Nobuo Funabiki

    2013 IEEE 2nd Global Conference on Consumer Electronics, GCCE 2013   530 - 533   2013

     More details

    Language:English  

    To enhance the user privacy at authentications, an anonymous credential system has been designed to allow a user to anonymously convince a verifier of the possession of a certificate issued by the issuing authority. In this system, a user can prove relations on his/her attributes embedded into the certificate. Previously, we have proposed an anonymous credential system with constant-size proofs and faster proof generations for CNF formulas than the existing system. In the system, in the verification, some value should be included in some set Φ. Unfortunately, this system has a problem of requiring long public parameters that is proportional to the size of the set Φ. In this paper, we propose an extension to reduce the public key by separating this set Φ into two sets Φ1 and Φ2 with logarithmic sizes such that u1 Φ1 and u2 Φ2 if and only if u1 +u2 Φ. Furthermore, we evaluate the efficiency based on the implementation. © 2013 IEEE.

    DOI: 10.1109/GCCE.2013.6664912

    Scopus

    researchmap

  • An extension of clustering algorithm for considering link speed in wireless mesh networks

    Shigeto Tajima, Nobuo Funabiki, Teruo Higashino

    2013 IEEE 2nd Global Conference on Consumer Electronics, GCCE 2013   500 - 504   2013

     More details

    Language:English  

    As a scalable Internet-access network, we have studied Wireless Internet-access Mesh Network (WIMNET) using multiple access point (APs) that are connected through wireless communications. In previous studies, we proposed a clustering algorithm for efficiently composing a large scale WIMNET by partitioning the APs into a set of clusters. This algorithm assumes that any link speed is constant for simplicity, whereas our preliminary experiments found that it is greatly changed as the link distance increases due to interferences when adopting the new high-speed IEEE802.11n protocol. In this paper, we extend our clustering algorithm to consider this link speed change to introduce IEEE802.11n into WIMNET. We verify the effectiveness of the extended algorithm through simulations in a grid topology instance using the WIMNET simulator. © 2013 IEEE.

    DOI: 10.1109/GCCE.2013.6664902

    Scopus

    researchmap

  • Extensions of cooking guidance function on Android tablet for homemade cooking assistance system

    Yukiko Matsushima, Nobuo Funabiki, Yijia Zhang, Toru Nakanishi, Kan Watanabe

    2013 IEEE 2nd Global Conference on Consumer Electronics, GCCE 2013   397 - 401   2013

     More details

    Authorship:Lead author   Language:English  

    Previously, we proposed a cooking-step scheduling algorithm to find a schedule of applying the cooking steps in the recipes for efficiently cooking multiple dishes simultaneously, to help healthy and cost-efficient lives for busy person. Then, we implemented a cooking guidance function on an Android tablet to navigate the cooking schedule in a kitchen. Although we confirmed the effectiveness through cooking experiments, we found three problems: 1) a user may click a starting button even if the previous required steps are not completed, 2) a user may miss the proper timing to stop a cooking-step, and 3) the duration time for a cooking-step may be varied by a user skill or a dish nature. In this paper, we extend the cooking guidance function by adding three features of starting condition checking, time-up alarming, and cooking rescheduling to solve these problems. We verify the effectiveness of the extended guidance function through experimentally cooking four dishes. © 2013 IEEE.

    DOI: 10.1109/GCCE.2013.6664869

    Scopus

    researchmap

  • An extension of menu planning algorithm for two-phase homemade cooking

    Nobuo Funabiki, Yukiko Matsushima, Toru Nakanishi, Kan Watanabe

    2013 IEEE 2nd Global Conference on Consumer Electronics, GCCE 2013   352 - 356   2013

     More details

    Authorship:Lead author   Language:English  

    Nowadays, many people keep busy lives due to working in companies, studying in schools, or taking care of children or senior parents. As a result, it has become very hard for them to cook foods for suppers by themselves at home after long-hour duties at daytime in weekdays. Previously, to assist homemade cooking of such busy people, we proposed a two-phase cooking such that the preparation phase of cooking foods that they will eat on the following weekdays is performed on a weekend, and the finishing phase for the foods for a supper is completed on the day in short time. Then, we presented a menu planning algorithm to assist generating one-week menus for this two-phase cooking. Unfortunately, we found that this algorithm has the following drawbacks in practical use: 1) the selection of food preference is not easy, 2) the use of preferred ingredients for cooking cannot be directly specified, and 3) the nutrition balance of foods in a menu is not considered. In this paper, we extend this algorithm to solve them by newly defining a preference index and the food balance guide by Japanese government. We verify the effectiveness of the extended algorithm through generating five-day menus from 241 food candidates. © 2013 IEEE.

    DOI: 10.1109/GCCE.2013.6664853

    Scopus

    researchmap

  • A graph-based algorithm for fill-in-blank problem generation in Java programming learning assistant system

    Nobuo Funabiki, Tana, Toru Nakanishi, Kan Watanabe

    The 3rd International Conference on Applied and Theoretical Information Systems Research (ATISR2013)   2013

     More details

    Authorship:Lead author   Language:English  

    researchmap

  • A fixed backoff-time switching method for wireless mesh networks: Design and Linux implementation

    Sritrusta Sukaridhoto, Nobuo Funabiki, Dadet Pramudihanto, Zainal Arief

    Proceedings - 2013 International Conference on Information Technology and Electrical Engineering: "Intelligent and Green Technologies for Sustainable Development", ICITEE 2013   248 - 253   2013

     More details

    Language:English   Publisher:IEEE Computer Society  

    As a flexible and cost-efficient scalable Internet access network, we have studied architectures, protocols, and design optimizations of the Wireless Internet-Access Mesh NETwork (WIMNET). WIMNET is composed of wirelessly connected access points (APs), where any host can basically access to the Internet through multihop communications between APs with IEEE 802.11 standard. In WIMNET, undesirable situations can often happen such that some links dominate the bandwidth while others become insufficient due to the limited shared bandwidth. However, the contention resolution mechanism using a random backoff-time in the CSMA/CA protocol of 802.11 standards is not sufficient for handling real-time traffic in multihop wireless communications. Previously, we have proposed the concept of the CSMA-based Fixed Backoff time Switching (CSMA-FBS) method for WIMNET to improve the performance by giving necessary link activation chances for multi-hop communications. We implemented our proposal on the QualNet simulator, and verify its effectiveness through simulations. In this paper, we present an implementation of the FBS method in Linux kernel to show its practicality and investigate the performance in a real network. Our design consists of implementations or modifications of the five programs: Kernel configuration, Debugfs, Minstrel, iw, and FBSdaemon. © 2013 IEEE.

    DOI: 10.1109/ICITEED.2013.6676247

    Scopus

    researchmap

  • An access-point aggregation approach for energy-saving wireless local area networks

    Md. Ezharul Islam, Nobuo Funabiki, Toru Nakanishi, Kan Watanabe

    IEICE Transactions on Communications   E96-B ( 12 )   2986 - 2997   2013

     More details

    Language:English   Publisher:Institute of Electronics, Information and Communication, Engineers, IEICE  

    Nowadays, with spreads of inexpensive small communication devices, a number of wireless local area networks (WLANs) have been deployed even in the same building for the Internet access services. Their wireless access-points (APs) are often independently installed and managed by different groups such as departments or laboratories in a university or a company. Then, a user host can access to multiple WLANs by detecting signals from their APs, which increases the energy consumption and the operational cost. It may also degrade the communication performance by increasing interferences. In this paper, we present an AP aggregation approach to solve these problems in multiple WLAN environments by aggregating deployed APs of different groups into limited ones using virtual APs. First, we formulate the AP aggregation problem as a combinatorial optimization problem and prove the NP-completeness of its decision problem. Then, we propose its heuristic algorithm composed of five phases. We verify the effectiveness through extensive simulations using the WIMNET simulator. Copyright © 2013 The Institute of Electronics, Information and Communication Engineers.

    DOI: 10.1587/transcom.E96.B.2986

    Scopus

    researchmap

  • An Extension of Credibility Formula in Desktop Grid to Different Workers' Performance

    2012 ( 16 )   1 - 8   2012.12

     More details

  • A Web Service Implementation of ◆ Attribute Authentication

    HAMADA Yuji, NAKANISHI Toru, WATANABE Kan, FUNABIKI Nobuo

    IEICE technical report. Life intelligence and office information systems   112 ( 306 )   41 - 46   2012.11

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Our research group has proposed the anonymous authentication scheme using user's attributes. In this scheme, the user can anonymously convince a verifier of the possession of attributes specified by the service provider with the complexity independent of the number of attributes. Previously, we have implemented Web system where the user proves the AND relations to a verifier. However, we cannot prove CNF fomulas that is the conbination of AND and OR relations at our Web system. In this study, we implemented the anonymous attributes authentication system for CNF fomulas using proxies and a questionnaire service as a Web service. We measured the communication times including the authentication times. The results show that our system is sufficiently practical.

    CiNii Article

    CiNii Books

    researchmap

  • An Implementation of Anonymous Attributes Authentication System on Android Smart Phone

    2012 ( 3 )   146 - 152   2012.10

     More details

    Language:Japanese  

    CiNii Article

    researchmap

  • An Implementation of Reputation System with Secrecy Even for Administrators

    2012 ( 3 )   828 - 834   2012.10

     More details

    Language:Japanese  

    CiNii Article

    researchmap

  • An Extension of Wireless Internet-Access Mesh Network Simulator for Smart Antenna Use and Evaluations Using Simple Topologies

    TAJIMA Shigeto, FUNABIKI Nobuo, HIGASHINO Teruo

    IEICE technical report   112 ( 231 )   125 - 130   2012.10

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As an inexpensive, flexible, and scalable Internet-access network, we have studied architecture, protocols, and design optimizations of the Wireless Internet-access Mesh NETwork (WIMNET). WIMNET consists of multiple access-points (APs) as wireless routers that are connected through wireless links. To improve the performance by realizing high-speed and simultaneous plural link communications, we have considered use of the smart antenna as a generalized technology of the Multiple-Input-Multiple-Output (MIMO) channel and the Adaptive Array Antenna (AAA). In this paper, we present an extension of the WIMNET simulator for the smart antenna use, which has been developed by our group to estimate the throughput in WIMNET. Through simulations in simple topologies, we investigate impacts of two smart antenna use methods and of interval changes between adjacent nodes including APs and hosts, into the performance of WIMNET.

    CiNii Article

    CiNii Books

    researchmap

  • An Implementation of Code Design Learning Function in Java Programming Learning Assistant System

    NAKAMURA Takuya, FUNABIKI Nobuo, NAKANISHI Toru, WATANABE Kan, AMANO Noriki

    IEICE technical report. Education technology   112 ( 224 )   17 - 22   2012.9

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Java has been educated in a lot of universities and professional schools due to the reliability, portability, and easy learning. To assist Java educations, our group has developed a Web-based Java Programming Learning Assistant System (JPLAS) that helps students to study Java programming by themselves through automatic testing of Java codes from students using the test-driven development method. Unfortunately, JPLAS is not suitable for less-experienced students in Java because they have to understand test codes that are necessary in automatic testing before writing source codes. In this paper, we propose a code design learning function in JPLAS to let such students learn how to collect the necessary information for a source code from a test code. A code design result from a student is automatically verified through comparisons with the corresponding model answer from a teacher. We verify the effectiveness of our proposal through applications to 24 students in our department.

    CiNii Article

    CiNii Books

    researchmap

  • A Linux Implementation Design of Fixed Backoff-time Switching Method for Wireless Mesh Networks

    SUKARIDHOTO Sritrusta, FUNABIKI Nobuo, NAKANISHI Toru, WATANABE Kan, Shigeto TAJIMA

    IEICE technical report   112 ( 208 )   83 - 88   2012.9

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As a flexible and cost-efficient scalable Intenet access network, we have studied architectures, protocols, and design optimizations of the Wireless Internet-access Mesh NETwork (WIMNET). WIMNET is composed of wirelessly connected access points(APs), where any host can basically access to the Internet through multihop communications between APs.In WIMNET, undesirable situations can often happen such that some links dominate the bandwidth while others become insufficient due to the limited shared bandwidth. To improve the performance by avoiding them, controls of activation chances for wireless links depending on their traffics are effective. Thus, previously, we have proposed the Fixed Backoff-time Switching (FBS) method for the CSMA/CA protocol, and verified the effectiveness using the QualNet simulator. In this paper, we present an implementation design of the FBS method in Linux kemel to show its practicality and investigate the performance in a real network. Our design consists of implementations or modifications of the five programs:Kernel configuration, Debugfs,Minstrel,iw, and FBSdaemon.

    CiNii Article

    CiNii Books

    researchmap

  • BS-5-29 An Idea of Linux Implementation of Fixed Backoff-time Switching Method for Wireless Mesh Networks(BS-5. Network and Service Design, Control and Management)

    Sukaridhoto Sritrusta, Funabiki Nobuo, Nakanishi Toru, Watanabe Kan, Tajima Shigeto

    Proceedings of the Society Conference of IEICE   2012 ( 2 )   "S - 82"-"S-83"   2012.8

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As a flexible and cost-efficient scalable Internet access network, we have studied architectures,protocols, and design optimizations of the Wireless Internet-access Mesh NETwork (WIMNET). WIMNET is composed of wireless connected access points. Previously, we proposed the Fixed Backoff-time Switching (FBS) method for the CSMA/CA protocol to improve the real-time traffic performance in WIMNET by giving the necessary activation chances to each link, and verified the effectiveness using the QualNet simulator. In this paper, we present an idea of the FBS method implementation at Linux kernel after quickly reviewing it.

    CiNii Article

    CiNii Books

    researchmap

  • An Extension of Cooking-Step Scheduling Algorithm for Simultaneous Cooking of Multiple Dishes

    MATSUSHIMA Yukiko, FUNABIKI Nobuo, NAKANISHI Toru, WATANABE Kan

    IEICE technical report. Image engineering   112 ( 189 )   1 - 6   2012.8

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    To assist homemade cooking of busy persons such as working people and child-growing families, we have proposed a cooking-step scheduling algorithm for multiple dishes. By composing the cooking procedure for each dish as a sequence of cooking-steps, this algorithm generates an optimal schedule of the cooking-steps for multiple dishes to minimize the cooking time while considering the constraints of cooks and instruments as a cooking model. In this paper, to enhance the practicality, we extend the algorithm in 1) accommodating the continuous cooking-steps such as boiling ingredients soon after stirring for a dish cooked by boiling or stewing, 2) suggesting the clearance chance of used instruments at a long waiting time, 3) preferentially assigning any possible cooking-step of the preferred dish to the sub-cook, and 4) considering the skill level of a cook in the operating time of a cooking-step. Through simulations and cooking experiments using five dishes, we verify the effectiveness of our algorithm extensions.

    CiNii Article

    CiNii Books

    researchmap

  • An Extension of Cooking-Step Scheduling Algorithm for Simultaneous Cooking of Multiple Dishes

    MATSUSHIMA Yukiko, FUNABIKI Nobuo, NAKANISHI Toru, WATANABE Kan

    IEICE technical report. Life intelligence and office information systems   112 ( 188 )   1 - 6   2012.8

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    To assist homemade cooking of busy persons such as working people and child-growing families, we have proposed a cooking-step scheduling algorithm for multiple dishes. By composing the cooking procedure for each dish as a sequence of cooking-steps, this algorithm generates an optimal schedule of the cooking-steps for multiple dishes to minimize the cooking time while considering the constraints of cooks and instruments as a cooking model. In this paper, to enhance the practicality, we extend the algorithm in 1) accommodating the continuous cooking-steps such as boiling ingredients soon after stirring for a dish cooked by boiling or stewing, 2) suggesting the clearance chance of used instruments at a long waiting time, 3) preferentially assigning any possible cooking-step of the preferred dish to the sub-cook, and 4) considering the skill level of a cook in the operating time of a cooking-step. Through simulations and cooking experiments using five dishes, we verify the effectiveness of our algorithm extensions.

    CiNii Article

    CiNii Books

    researchmap

  • A Pairing-Based Anonymous Credential System with Efficient Attribute Proofs

    Amang Sudarsono, Toru Nakanishi, Nobuo Funabiki

    53 ( 6 )   11p   2012.6

  • A Generalization of WDS Clustering Algorithm Extension to Smart-Antenna in Wireless Mesh Networks

    TAJIMA Shigeto, FUNABIKI Nobuo, TOMISATO Shigeru, HATA Masaharu, HIGASHINO Teruo

    IEICE technical report   112 ( 8 )   37 - 42   2012.4

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As a scalable inexpensive Internet-access network, we have studied the Wireless Internet-access Mesh Network (WIMNET) that is composed of multiple access point (APs) connected through the Wireless Distribution System (WDS). Because all the traffics pass through an Internet gateway (GW) in WIMNET, the resolution of link congestions around the GW is very important. For this problem, we have proposed a WDS clustering algorithm to partition the APs into a set of WDS clusters where the APs in each cluster shares an GW, and have considered the adoption of a smart antenna for a Smart AP (SAP). Since the smart antenna is usually expensive, we have extended the WDS clustering algorithm to a cluster where only one or two SAPs are used. In this paper, we generalize this extension to a cluster with an arbitrary number of SAPs. Besides, we investigate the priority action of the smart antenna for multiple SAPs in one cluster. We evaluate the effectiveness through simulations using grid topology instances.

    CiNii Article

    CiNii Books

    researchmap

  • BS-3-17 LOAD BALANCING STAGE FOR AN ACCESS-POINT AGGREGATION ALGORITHM IN WIRELESS LOCAL AREA NETWORKS(BS-3. Management and Control Technologies for Innovative Networks)

    Islam Md. Ezharul, Funabiki Nobuo, Nakanishi Toru, Watanabe Kan

    Proceedings of the IEICE General Conference   2012 ( 2 )   "S - 33"-"S-34"   2012.3

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Currently, many organizations such as universities and companies are using multiple wireless local area networks (WLANs) even in the same building, where wireless access-points (APs) are independently managed by different groups such as departments or laboratories. As a result, a WLAN user host can detect signals from multiple APs, which may increase the interference and degrade the communication performance. Therefore, we have proposed an AP aggregation algorithm to minimize the number of active physical APs by aggregating the APs in the field by introducing virtual APs. In this paper, we introduce a load balancing stage to this algorithm to maximize the throughput by balancing loads among APs. The effectiveness has been verified through simulations in two instances.

    CiNii Article

    CiNii Books

    researchmap

  • An Extension of Web-based Assistance System for Computer-Scored Paper Tests

    TAKAKI Shogo, FUNABIKI Nobuo, NAKANISHI Toru, WATANABE Kan, AMANO Noriki

    IEICE technical report. Education technology   111 ( 473 )   243 - 248   2012.3

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    A frequent application of mini-exams and quizzes during classes can be effective to enhance the educational effects to students in universities. However, teachers may have to spend much time to prepare the test papers before classes, and grade the test papers from students after them. In order to ease such burdens of teachers, we have proposed a Web-based assistance system for computer-scored paper tests in conventional lecture rooms without computers for students. This system supports the test paper generation, the test paper grading, and the score management. In this paper, we extend the system by adding two new question types, implementing the test paper preview function, and providing the data export function to the Web quiz function in an existing learning assistant system. We evaluate the effectiveness of our proposal through an experiment in one class in our department.

    CiNii Article

    CiNii Books

    researchmap

  • An Extension of Fill-in-the-blank Problem Function in Java Programming Learning Assistant System and Its Application to Class

    KORENAGA Yousuke, FUNABIKI Nobuo, NAKANISHI Toru, WATANABE Kan, AMANO Noriki

    IEICE technical report. Education technology   111 ( 473 )   7 - 12   2012.3

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    The programming language Java has been educated in a lot of universities and professional schools due to the reliability, portability, and easy learning. To assist this Java education, our group has developed a Web-based Java Programming Learning Assistant System (JPLAS) by supporting self-studies of students. JPLAS has the fill-in-the-blank problem function for Java novice students to study Java reserved words. In this function, a teacher first generates fill-in-the-blank problems automatically by removing the specified reserved words randomly from a sample Java code in the database. Then, a student can repeatedly submit answers to the problems until all the answers are correct as self-studies. In this paper, we implement the score graph function so that the students can complete with each other in solving fill-in-the-blank problems by referring the current scores of other students. We apply the function to students in a Java programming class in our department to evaluate the effectiveness of our proposal.

    CiNii Article

    CiNii Books

    researchmap

  • An Implementation of Erroneous Code Indication Function in Java Programming Learning Assistant System Using Test-Driven Development Method

    FUKUYAMA Yuki, FUNABIKI Nobuo, NAKANISHI Toru, WATANABE Kan, AMANO Noriki

    IEICE technical report. Education technology   111 ( 473 )   1 - 6   2012.3

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    To enhance the effect of the Java programming education by assisting self-studies of students, we have proposed a Web-based Java Programming Learning Assistant System (JPLAS) using the test-driven development (TDD) method. In this system, a teacher first registers an exercise subject, a model source code, and a test code. Then, a student submits the answer code on the subject. The answer code is automatically verified by the verification tool at the server, and the verification result log is returned to the student. However, in the current system, even reading the log to find the errors is actually difficult for a student who is a Java programming beginner. In this paper, we implement an erroneous code indication function in JPLAS of graphically showing the error parts on the code. We evaluate the effectiveness of this function through an experiment to 42 students who are learning Java.

    CiNii Article

    CiNii Books

    researchmap

  • An Internship Instance of Developing an Assistance System for Promoting Group Events Using Ruby

    OKADA Tomoya, KORENAGA Yousuke, HAMADA Yuji, IKEDA Daiki, SHIMIZU Junki, TAKEBAYASHI Tatuya, FUNABIKI Nobuo, NAKANISHI Toru, Ishihara HIROYUKI, SATOU Junyuki, OTORI Yoshinori, KOHMOTO Takayuki, OHTA Mayumi

    IEICE technical report. Education technology   111 ( 394 )   35 - 40   2012.1

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    The Graduate School of Natural Science and Technology in Okayama University has offered a special exercise class named "Internship in Engineering and Science" so that the students can experience practical works in companies through long term internships there. In the past two years, we have had the exercise at Systems Nakashima Co., Ltd. in developing a Web application system using Ruby for promoting events such as travels and parties in groups by helping the event planning, the attendance confirmation, and the schedule management. In this paper, we introduce the content of this exercise and the outline of the developed system. Besides, we describe the feedbacks of the students on this exercise.

    CiNii Article

    CiNii Books

    researchmap

  • Training Program for Practical Engineering Design through the Collaboration with Regional Companies

    GOFUKU Akio, TABATA Nobuhisa, TOMITA Eiji, FUNABIKI Nobuo

    Journal of Jsee   60 ( 1 )   52 - 57   2012.1

     More details

    Language:Japanese   Publisher:Japanese Society for Engineering Education  

    An education program to bring up engineering design capabilities through long-term internship by the collaboration with regional companies has been put in practice for five years. The program is composed of two types of long-term internships and several lectures for patent systems and engineering ethics. This paper describes the outline of the program, educational effects, and our experiences. The program was improved into two educational programs in 2011. The one is a special course to educate engineers and scientists who can lead the technologies of their domains. The other is a long-term internship program for master students in engineering divisions of graduate school. This paper also describes the current activities of the latter program.

    DOI: 10.4307/jsee.60.1_52

    CiNii Article

    CiNii Books

    researchmap

  • Combinational Effect of Spot-checking in Sabotage-tolerance for Volunteer Computing

    WATANABE Kan, FUNABIKI Nobuo, NAKANISHI Toru, FUKUSHI Masaru

    111 ( 408 )   103 - 108   2012.1

     More details

  • An Improved Java Programming Learning System Using Test-Driven Development Method

    Nobuo Funabiki, Yuuki Pukuyama, Yukiko Matsushima, Toru Nakanishi, Kan Watanabe

    INTERNATIONAL MULTICONFERENCE OF ENGINEERS AND COMPUTER SCIENTISTS, IMECS 2012, VOL I   597 - 602   2012

     More details

    Authorship:Lead author   Language:English   Publisher:INT ASSOC ENGINEERS-IAENG  

    To enhance educational effects of Java programming by assisting self-studies of students and reducing teaching loads of teachers, we have proposed a Web-based Java programming learning system using the test-driven development method. In this system, a teacher should register Java programming assignments with statements, model source codes, and test codes using a Web browser. Then, a student can submit a test code and an answer source code for each assignment, where both codes are tested automatically by a testing tool called Junit at the server. Unfortunately, the current system cannot identify an incomplete test code that does not contain the complete test procedures if it has no grammatical error. In this paper, we introduce a code coverage measurement tool called Cobertura to detect such a test code by measuring the coverage rate when the submitted test code tests the model source code. We evaluate the effectiveness of our improved system through experiments with two simple assignments to 11 students who have studied Java.

    Web of Science

    researchmap

  • A dynamic rescheduling extension of cooking-step scheduling algorithm for multiple dish cooking

    Yukiko Matsushima, Nobuo Funabiki, Toru Nakanishi, Kan Watanabe

    The 2nd International Conference on Applied and Theoretical Information Systems Research (2nd ATISR2012)   2012

     More details

    Language:English  

    researchmap

  • A code design learning function in Java programming learning assistant system using test-driven development method

    Nobuo Funabiki, Takuya Nakamura, Yukiko Matsushima, Toru Nakanishi, Kan Watanabe

    The 2nd International Conference on Applied and Theoretical Information Systems Research (2nd ATISR2012)   2012

     More details

    Authorship:Lead author   Language:English  

    researchmap

  • An application of cooking-step scheduling algorithm for homemade cooking and its extensions

    Yukiko Matsushima, Nobuo Funabiki, Toru Nakanishi, Kan Watanabe

    1st IEEE Global Conference on Consumer Electronics 2012, GCCE 2012   94 - 98   2012

     More details

    Language:English  

    Homemade cooking can have a key role for a healthy and cost-efficient life. To help this activity for busy people such as workers, students, and child-rearing families, we have proposed a cooking-step scheduling algorithm to suggest an optimal sequence of the cooking-steps when multiple dishes are cooked within a limited time. In this algorithm, the cooking procedure for each dish is divided into a set of cooking-steps, and the execution sequence of all the cooking-steps for the dishes is optimized such that the total cooking time is minimized. In this paper, we first show our application result of this algorithm in cooking five dishes and the arisen problems through this experiment. Then, we present four extensions of this algorithm to solve them. Through simulations and cooking experiments, we verify the effectiveness of the algorithm extensions. © 2012 IEEE.

    DOI: 10.1109/GCCE.2012.6379977

    Scopus

    researchmap

  • An extension of routing tree algorithm for smart antenna use in wireless Internet-access mesh network

    Nobuo Funabiki, Toru Nakanishi, Kan Watanabe

    1st IEEE Global Conference on Consumer Electronics 2012, GCCE 2012   633 - 637   2012

     More details

    Authorship:Lead author   Language:English  

    As a cost-efficient scalable Internet-access network, we have studied the architecture, protocols, and design optimizations of the Wireless Internet-access Mesh NETwork (WIMNET). WIMNET is composed of wirelessly connected multiple access-points (APs), where at least one AP acts as a Gateway (GW) to the Internet. Two types of APs are used for the hierarchical configuration to achieve scalability with sufficient bandwidth and low costs, namely, a programmable Smart AP (SAP) equipped with multiple antennas, and a non-programmable Conventional AP (CAP) with a single antenna. For a SAP, a smart antenna using an array antenna should be adopted to enhance the performance by allowing simultaneous activations of multiple links. Because the transmission capacity of a SAP with m antennas can be ideally m times of that of a CAP, the routing path should consider this difference so that the average delay between the GW and any AP be minimized to avoid bottlenecks. In this paper, we present an extension of our previous routing tree algorithm for this smart antenna use in WIMNET to improve the throughput by considering the feature. We evaluate the throughput improvement through simulations using the WIMNET simulator. © 2012 IEEE.

    DOI: 10.1109/GCCE.2012.6379938

    Scopus

    researchmap

  • Implementation and Evaluation of an Pairing-Based Anonymous Credential System with Constant-Size Proofs and Efficient Proof Generations

    Nasima Begum, Toru Nakanishi, Nobuo Funabiki

    2012 THIRD INTERNATIONAL CONFERENCE ON NETWORKING AND COMPUTING (ICNC 2012)   264 - 268   2012

     More details

    Language:English   Publisher:IEEE  

    To enhance user privacy, anonymous credential systems allow the user to convince a verifier of the possession of a certificate issued by the issuing authority anonymously. In the systems, the user can prove logical relations on his/her attributes embedded into the certificate. Previously, we proposed a pairing-based system with constant-size proofs. In the system, the proof generation needs only multiplications depending on the size of the proved relations, and it is more efficient than other existing system that needs the exponentiations whose costs are much larger than multiplications. However, our efficient system has never been implemented, and thus the practicality is not evaluated. In this study, we implemented the system, and measured the processing times and data size, when changing the parameters describing the size of the proved relation. The verification time is very fast and constant, and the proof size is also constant, from which we can confirm the practicality. However, the proof generation time increases, when the parameters increase. Although we confirm the practicality in case of small relations, we clarify the problems in case of larger relations, which should be solved in our future works.

    DOI: 10.1109/ICNC.2012.48

    Web of Science

    researchmap

  • Efficient proofs for CNF formulas on attributes in pairing-based anonymous credential system

    Nasima Begum, Toru Nakanishi, Nobuo Funabiki

    15th Annual International Conference on Information Security and Cryptology (ICISC 2012)   2012

     More details

    Language:English  

    researchmap

  • An Error Code Highlighting Function in Java Programming Learning Assistant System Using Test-Driven Development Method

    Nobuo Funabiki, Yuuki Fukuyama, Yukiko Matsushima, Toru Nakanishi, Kan Watanabe

    WORLD CONGRESS ON ENGINEERING AND COMPUTER SCIENCE, WCECS 2012, VOL I   230 - 235   2012

     More details

    Authorship:Lead author   Language:English   Publisher:INT ASSOC ENGINEERS-IAENG  

    Recently, the objected-oriented programming language Java has been used in many practical systems including enterprise servers, smart phones, and embedded systems due to its high reliability and portability. To enhance effects of Java programming educations, we have developed a Web-based Java Programming Learning Assistant System (JPLAS). JPLAS adopts the Test-Driven Development (TDD) method for automatic testing of source codes written by students on the server to assist their self-learning. In JPLAS, a teacher needs to register each Java programming assignment with a statement, a reference source code, and a test code. Then, students should write source codes by referring this statement and the test code so that their source codes can be tested automatically at the server by a testing software tool called JUnit with the test code. Unfortunately, the current JPLAS is not friendly to students who have difficulty in reading the log message from JUnit that contains the information on the errors in the source code. In this paper, we implement the error code highlighting function to help such students to find erroneous lines in the code by highlighting them graphically. We evaluate the effectiveness of this function through an experiment for 42 students who are currently taking the Java programming class.

    Web of Science

    researchmap

  • An extension of clustering algorithm for smart-antenna use in wireless mesh networks

    Shigeto Tajima, Nobuo Funabiki, Shigeru Tomisato, Masaharu Hata, Teruo Higashino

    1st IEEE Global Conference on Consumer Electronics 2012, GCCE 2012   638 - 642   2012

     More details

    Language:English  

    As a scalable cost-efficient Internet-access network, we have studied the Wireless Internet-access Mesh Network (WIMNET) that is composed of multiple access point (APs) connected through the Wireless Distribution System (WDS). Because all the traffics pass through an Internet Gateway (GW), the resolution of link congestions around the GW is very important. To solve this problem, we have proposed a clustering algorithm to partition the APs into a set of clusters where each cluster consists of the APs sharing the same GW. In addition, we have considered the use of a smart antenna at a special AP called a Smart AP (SAP). In this paper, we extend this clustering algorithm for smart antenna use at SAPs. Besides, we investigate the link activation strategy for the smart antenna, because it allows a variety of link activations for packet transmissions. We evaluate the effectiveness through simulations using the WIMNET simulator. © 2012 IEEE.

    DOI: 10.1109/GCCE.2012.6379939

    Scopus

    researchmap

  • A proposal of access-point aggregation approach for multiple wireless local area networks

    Nobuo Funabiki, Md. Ezharul Islam, Toru Nakanishi, Kan Watanabe

    4th International Workshop on Virtual Environment and Network-Oriented Applications (VENOA 2012)   668 - 673   2012

     More details

    Authorship:Lead author   Language:English  

    researchmap

  • A pairing-based anonymous credential system with efficient attribute proofs

    Amang Sudarsono, Toru Nakanishi, Nobuo Funabiki

    Journal of Information Processing   20 ( 3 )   774 - 784   2012

     More details

    Language:English  

    To enhance user privacy, anonymous credential systems allow the user to convince a verifier of the possession of a certificate issued by the issuing authority anonymously. The typical application is the privacy-enhancing electronic ID (eID). Although a previously proposed system achieves the constant complexity in the number of finiteset attributes of the user, it requires the use of RSA. In this paper, we propose a pairing-based anonymous credential system excluding RSA that achieves the constant complexity. The key idea of our proposal is the adoption of a pairing-based accumulator that outputs a constant-size value from a large set of input values. Using zero-knowledge proofs of pairing-based certificates and accumulators, any AND and OR relation can be proved with the constant complexity in the number of finite-set attributes. We implement the proposed system using the fast pairing library, compare the efficiency with the conventional systems, and show the practicality in a mobile eID application. © 2012 Information Processing Society of Japan.

    DOI: 10.2197/ipsjjip.20.774

    Scopus

    researchmap

  • A proposal of CSMA fixed backoff-time switching protocol and its implementation on QualNet simulator for wireless mesh networks

    Sritrusta Sukaridhoto, Nobuo Funabiki, Toru Nakanishi, Kan Watanabe

    Proceedings - 26th IEEE International Conference on Advanced Information Networking and Applications Workshops, WAINA 2012   520 - 525   2012

     More details

    Language:English  

    As an inexpensive and scalable Internet access network, we have studied the architecture, protocols, and design optimizations of the Wireless Internet access Mesh Network (WIMNET). WIMNET is composed of multiple access points (APs) that are connected through wireless links. Previously, we have proposed the concept of the CSMA-based Fixed Back off-time Switching (CSMA-FBS) method for WIMNET to improve the performance by giving necessary link activation chances for multi-hop communications. In this paper, we propose a protocol for this CSMA-FBS method implement able on APs, and its actual implementation on the QualNet simulator for evaluations in realistic network environments. The simulation results in two network topologies confirm the effectiveness of our proposal. © 2012 IEEE.

    DOI: 10.1109/WAINA.2012.69

    Scopus

    researchmap

  • An online fill-in-the-blank problem function for learning reserved words in Java programming education

    Nobuo Funabiki, Yousuke Korenaga, Yukiko Matsushima, Toru Nakanishi, Kan Watanabe

    Proceedings - 26th IEEE International Conference on Advanced Information Networking and Applications Workshops, WAINA 2012   375 - 380   2012

     More details

    Authorship:Lead author   Language:English  

    The Java programming education to students has been held in a lot of universities and professional schools due to the reliability, portability, and easy learning. To assist this education, our group has developed a Java programming learning system based on the test-driven development method. However, this Web system targets students who have studied Java to some extent. In this paper, we propose a fill-in-the-blank problem function for this system to assist the learning of the Java reserved words by novice Java learners. Our function consists of a teacher service process and a student service process. By the former one, a teacher can generate a fill-in-the-blank problem easily by blanking the specified reserved words randomly from a sample Java code in the database. By the latter one, a student can repeatedly submit answers of a problem until all the questions are correctly solved for self-study. The function is implemented on an existing Web system and is applied to students who are currently learning Java. The questionnaire result confirms the effectiveness of our proposal. © 2012 IEEE.

    DOI: 10.1109/WAINA.2012.64

    Scopus

    researchmap

  • An Extension of Routing Tree Algorithm Considering Link Speed Change in IEEE 802.11n Protocol for Wireless Mesh Network

    Nobuo Funabiki, Wataru Maruyama, Toru Nakanishi, Kan Watanabe

    2012 9TH INTERNATIONAL CONFERENCE ON UBIQUITOUS INTELLIGENCE & COMPUTING AND 9TH INTERNATIONAL CONFERENCE ON AUTONOMIC & TRUSTED COMPUTING (UIC/ATC)   600 - 605   2012

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE COMPUTER SOC  

    As an inexpensive, flexible, and scalable Internet-access network, we have studied architecture, protocols, and design optimizations of the Wireless Internet-access Mesh NETwork (WIMNET). WIMNET consists of multiple access-points (APs) as wireless routers that are connected through wireless links. One AP acts as a gateway (GW) to the Internet, where any host must reach there for the Internet access through multi-hop communications between APs. Because a lot of traffic must be handled by these links, the latest IEEE 802.11n protocol should be adopted to provide high-speed communications. In this paper, we first show that our throughput measurement results using commercial products implementing this protocol, reveal the quick drop of the throughput as the increase of the link distance. Then, we present extensions of our previously proposed routing tree algorithm for WIMNET and the WIMNET simulator in considering this link speed change by the distance. We verify the effectiveness of our proposals through simulations in four cases with different topologies.

    DOI: 10.1109/UIC-ATC.2012.162

    Web of Science

    researchmap

  • A Lattice Implementation of High-precision IIR Filter for X-ray CT Reconstruction

    Kazuhisa Hayashi, Hiroshi Tsutsu, Yoshitaka Morikawa, Nobuo Funabiki

    INTERNATIONAL MULTICONFERENCE OF ENGINEERS AND COMPUTER SCIENTISTS, IMECS 2012, VOL I   751 - 756   2012

     More details

    Authorship:Lead author   Language:English   Publisher:INT ASSOC ENGINEERS-IAENG  

    The authors previously proposed forward and backward one round (FBOR) method to accelerate the filtering process by realizing the discrete Hilbert transform (DHT) function using an IIR filter in the convolution backprojection (CB) method that is a typical reconstruction algorithm for the X-ray CT. The FBOR method cascades causal and anticausal allpass filters to realize the linear phase DHT, and implements them by parallel ladders of allpass filters. Unfortunately, this method has to adopt the DHT that has the brickwall transition at the zero frequency and thus, requires high sensitivity coefficients in order to reduce distortions of a reconstructed image. As a result, it needs to rely on double precision floating points to avoid cancellations of significant digits. In this paper, we propose a successive-scan one-round (SSOR) method of implementing the DHT by cascading primary lattice allpass filters that allows the use of single precision floating points. We confirm the effec-tiveness of our proposal through simulations.

    Web of Science

    researchmap

  • Modeling and Performance Evaluation of Colluding Attack in Volunteer Computing Systems

    Kan Watanabe, Nobuo Funabiki, Tom Nakanishi, Masaru Fukushi

    INTERNATIONAL MULTICONFERENCE OF ENGINEERS AND COMPUTER SCIENTIST, IMECS 2012, VOL II   1658 - 1663   2012

     More details

    Language:English   Publisher:INT ASSOC ENGINEERS-IAENG  

    This paper proposes a model of a colluding attack in Volunteer Computing (VC), where some of participants are unreliable and may return incorrect results. The colluding attack is one of the most important issues to realize reliable VC because it may ruin the most basic assumption, i.e. "the majority in voting is correct". Especially, check-by-voting archives the largest efficiency by sorting reliable participants based on whether their results are the majority or not. Thus, if some incorrect results become the majority by colluding attack, it may have significant impacts on check-by-voting. In this paper, we perform a Monte Carlo simulation of VC using the proposed colluding model and evaluate the sabotage-tolerance performance of voting methods. Simulation results show that check-by-voting works well if colluding attack happens.

    Web of Science

    researchmap

  • A Proposal of an Access-Point Aggregation Algorithm for Wireless Local Area Networks

    ISLAM Md. EZHARUL, FUNABIKI Nobuo, NAKANISHI Toru, WATANABE Kan

    IEICE technical report   111 ( 344 )   1 - 6   2011.12

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Nowadays, multiple wireless local area networks (WLANs) have been deployed in the same building of an institute including a company and a university. Usually, their wireless acess-points (APs) have been independently managed and operated by different groups in the building such as departments or laboratories. As a result, a WLAN user host can detect signals from multiple APs, which may increase the interference and degrade the communication performance. Thus, the minimization of the number of active physical APs by aggregating the allocated APs in the field by introducing virtual APs becomes one of the major challenges in WLANs. In this paper, we formulate this AP aggregation problem for WLANs of aggregating the APs into the minimum number of active APs, and propose its heuristic algorithm that is composed of four phases. The effectiveness of our proposal has been verified through simulations in two instances.

    CiNii Article

    CiNii Books

    researchmap

  • A Clustering Algorithm for WDS Clusters with Two Access-Points Using Smart Antenna in Wireless Mesh Networks

    TAJIMA Shigeto, FUNABIKI Nobuo, TOMISATO Shigeru, HATA Masaharu, HIGASHINO Teruo

    Technical report of IEICE. RCS   111 ( 345 )   81 - 86   2011.12

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As a scalable Internet access network, we have studied the Wireless Internet-access Mesh Network (WIMNET) that is composed of multiple access point (APs) connected through the Wireless Distribution System (WDS). For large scale WIMNET, because the traffic through the Internet gateway (GW) becomes very high, it is composed of multiple WDS clusters where one cluster consists of APs sharing the same GW. Even in this hierarchial WIMNET, links around the GW are still crowded in each WDS cluster and may become bottlenecks of whole communications. Hence, we have proposed the adoption of a Smart AP (SAP) using the smart antenna technology for bandwidth enhancements. In this paper, we propose an extension of our WDS clustering algorithm for WIMNET such that the GW and one adjacent AP are selected as SAPs in each WDS cluster. Through simulations using grid topology instances, we verify the effectiveness of our algorithm extension.

    CiNii Article

    CiNii Books

    researchmap

  • A Proposal of Efficient Range Proof Protocol for Anonymous Credential System

    IKEDA Daiki, NAKANISHI Toru, FUNABIKI Nobuo

    Technical report of IEICE. ISEC   111 ( 337 )   7 - 14   2011.12

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    An anonymous credential system allows a user to convince a verifier of the possession of user's attributes anonymously. A range proof protocol in an anonymous credential system is the protocol where the user can show that user's attribute belongs to a certain integer range without revealing the attribute. In the previous scheme, while the constant computational complexity is achieved, the size of the public parameters depends on the number of the attributes N. This paper proposes a range proof protocol with O (logTV) public parameter size. We also implement and evaluate it.

    CiNii Article

    CiNii Books

    researchmap

  • Proposal of Reputation System with Strong Secrecy for Managers

    NOMURA Tomoya, NAKANISHIV Toru, FUNABIKI Nobuo

    Technical report of IEICE. ISEC   111 ( 337 )   15 - 20   2011.12

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    In a P2P service such as Internet auctions, there is need for keeping users anonymous, but, in this case, misbehaving user becomes a problem. So, the anonymous users use a reputation system to evaluate each other, where the user can decide whether the other user is misbehaving user or not. However, in the system, the administrator can grasp the change of user's reputation point, it becomes a problem of privacy. In this study, we propose a reputation system with the anonimity even for the administrator by user's managing reputation points in the anonymous certificate. We evaluate the proposed system by processing time of the implementation.

    CiNii Article

    CiNii Books

    researchmap

  • Modeling and Performance Evaluation of Colluding Attack in Volunteer Computing

    WATANABE Kan, FUNABIKI Nobuo, NAKANISHI Toru, FUKUSHI Masaru

    IEICE technical report. Dependable computing   111 ( 252 )   25 - 30   2011.10

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    This paper proposes a model of a colluding attack in Volunteer Computing (VC), where some of participants are unreliable and may return incorrect results. The colluding attack is one of the most important issues to realize reliable VC because it may ruin the most basic requirement, i.e. "the majority in voting is correct". It is used in most current sabotage-tolerance techniques such as M-first voting. Especially, checkbyvoting archives the largest efficiency in current sabotage-tolerance techniques by using the technique called "check by voting" (using the result of a voting as a check). Thus, if some results of votings have been incorrect by colluding attack, it may have significant impacts on checkbyvoting. In this paper, we perform a Monte Carlo simulation of VC using the proposed model and evaluate the sabotage-tolerance performance for both checkbyvoting and M-first voting.

    CiNii Article

    CiNii Books

    researchmap

  • An Implementation of an Anonymous Authentication System with Exclusion of Illegal Users in the Web Services

    2011 ( 3 )   66 - 71   2011.10

     More details

    Language:Japanese  

    CiNii Article

    researchmap

  • An Implementation of Anonymous Attributes Authentication System for Web Services

    2011 ( 3 )   60 - 65   2011.10

     More details

    Language:Japanese  

    CiNii Article

    researchmap

  • An Improvement of Active Access-Point Selection Algorithm for Throughput Maximization in Wireless Mesh Networks

    SHIMIZU Junki, FUNABIKI Nobuo, NAKANISHI Toru, WATANABE Kan

    IEICE technical report   111 ( 232 )   25 - 30   2011.10

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    The wireless Internet-access mesh network (WIMNET) has been studied to realize the inexpensive, scalable Internet-access network by adopting multiple access points (APs) connected by wireless links. WIMNET can improve the dependability to failures of APs and/or links by allocating APs redundantly, whereas redundant APs may cause the increase of the operational cost and the degradation of the throughput due to increasing radio interferences. Therefore, we have formulated the active AP selection problem of selecting the minimum number of active APs among redundant APs in WIMNET and proposed its heuristic algorithm. The simulation results indicated the existence of an active AP selection maximizing the throughput whose number of active APs is larger than the minimum. In this paper, we improve this algorithm for the throughput maximization. We verify the effectiveness of our algorithm improvement through simulations in three instances.

    CiNii Article

    CiNii Books

    researchmap

  • An Improvement of Code Verifications in Java Programming Learning System Using Test-Driven Development Method

    FUKUYAMA Yuki, FUNABIKI Nobuo, NAKANISHI Toru, WATANABE Kan, AMANO Noriki

    IEICE technical report   111 ( 213 )   13 - 18   2011.9

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    For the enhancement of the Java programming education by assisting self-studies of students and reducing loads of teachers, we have proposed and developed a Web-based Java programming learning system using the test-driven development method. In this system, the teacher first registers an exercise subject, a model source code, and a test code. Then, the student submits the test code and the answer code, which are verified by the verification tool at the server. Unfortunately, the current system cannot detect an incomplete test code from a student that does not contain necessary test procedures if it has no grammatical error. In this paper, we introduce a code coverage verification tool into the system in order to find an incomplete test code. After implementing this proposal, we evaluate the effectiveness of the improved system through experiments to 11 students who have studied Java.

    CiNii Article

    CiNii Books

    researchmap

  • An Implementation and Evaluation of Fixed Backoff-time Switching Method on QualNet for Wireless Mesh Network

    SUKARIDHOTO Sritrusta, FUNABIKI Nobuo, NAKANISHI Toru, WATANABE Kan, TAJIMA Shigeto

    IEICE technical report   111 ( 91 )   33 - 38   2011.6

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As an inexpensive and scalable access network to the Internet, we have studied the architecture, protocols, and design optimizations of Wireless Internet access Mesh Network (WIMNET). WIMNET is composed of multiple access points (APs) connected through wireless links. Previously, we have proposed the CSMA -based Fixed Backoff-time Switching (CSMA-FBS) method for WIMNET to improve the performance by giving necessary link activation chances for multi-hop communications. In this study, we implement the CSMA-FBS method on the QualNet simulator for evaluations in more realistic network environments. The simulation results in three network topologies confirm the effectiveness of our proposal.

    CiNii Article

    CiNii Books

    researchmap

  • A WDS Clustering Algorithm for Wireless Mesh Network with Gateway using MIMO Channel

    TAJIMA Shigeto, FUNABIKI Nobuo, TOMISATO Shigeru, HATA Masaharu, HIGASHINO Teruo

    IEICE technical report   111 ( 8 )   55 - 60   2011.4

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    We have studied the Wireless Internet-access Mesh NETwork (WIMNET) as a scalable wireless local area network that is composed of multiple access points (APs) connected through the Wireless Distribution System (WDS). To avoid the performance degradation due to traffic overloads, the number of APs in a single WDS is limited. Hence, we have proposed a WDS clustering algorithm to partition a given set of APs into a disjoint set of WDS clusters where the APs in one WDS cluster shares a single gateway (GW) to the Internet and are connected by a single WDS. As all the traffics from/to the Internet pass through the GW in a WDS cluster, links incident to the GW can be bottlenecks of whole communications. In this paper, in order to increase the throughput there by adopting the MIMO channel at the GW, we propose an extension of the WDS clustering algorithm to the WIMNET with the MIMO channel GW. Through simulations using several instances, we verify the effectiveness of our algorithm extension.

    CiNii Article

    CiNii Books

    researchmap

  • An Implementation of an Online Fill-in-the-blank Problem Function for Learning Reserved Words in Java Programming

    KORENAGA Yousuke, MATSUSHIMA Yukiko, FUNABIKI Nobuo, NAKANISHI Toru, AMANO Noriki

    IEICE technical report   110 ( 453 )   125 - 130   2011.2

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    The Java programming has been educated to students in a lot of universities and professional schools due to its reliability, portability, and easy learning. To assist the education, our group has developed a Java programming education assistant system based on the test-driven development method. However, this system targets students who have studied Java to some extent. In this paper, we propose the online fill-in-the-blank problem function for this Web system to assist the learning of the reserved words of Java for Java beginners. This function consists of the teacher service function and the student service function. By the former function, a teacher can generate a fill-in-the-blank problem automatically by removing the specified reserved words randomly from a sample Java code in the database. By the latter function, a student can repeatedly submit answers of a problem until all the answers are correct for self-study. The function is implemented at the existing system and is applied to students who are Java beginners, where the questionnaire result confirms the effectiveness of our proposal.

    CiNii Article

    CiNii Books

    researchmap

  • An Implementation of a Web-based Assistance System for Computer-Scored Tests

    KAWANO Hiroki, FUNABIKI Nobuo, NAKANISHI Toru, AMANO Noriki

    IEICE technical report   110 ( 453 )   193 - 198   2011.2

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Mini-exams and quizzes during classes can be effective to enhance their educational effects to students in universities. However, teachers may have to spend much time to prepare test materials before classes, and grade the test papers from students after them. In this paper, we propose a Web-based assistance system for computer-scored tests in order to reduce these loads by teachers. Our system consists of the question generation & management function, the test generation & management function, the subject generation & management function, the test grading function, and the learning history management function. By treating questions and tests separately such that one test is composed of individual questions, this system makes it possible to reuse existing questions and tests in various subjects by sharing them among teachers. Besides, by automatically generating test papers containing randomly shuffled options, it can prevent students from cheating by peeking at papers of other students at neighbor seats. To evaluate the efficiency, we implemented the system by extending the existing learning management system NOBASU, and applied it to one class in our department.

    CiNii Article

    CiNii Books

    researchmap

  • An Implementation of Menu Planning and Cooking Step Optimization Functions in a Web-based Homemade Cooking Assistance System for Busy Persons

    OKADA Tomoya, MATUSHIMA Yukiko, TANIGUCHI Shiho, FUNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report   110 ( 453 )   205 - 210   2011.2

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    For busy persons such as workers, students, and child-growing families, preparations of dishes by homemade cooking may become heavy burdens on weekdays. To solve this problem, our group has developed a Web-based homemade cooking assistance system composed of four main functions. In this paper, we implement the two functions of the menu planning and the cooking step optimization for this system. The first function helps a user to generate a menu manually, or automatically by using the menu selection algorithm. Besides, it allows the user to register the menu information into Google calendar so that the information can be accessed even from a mobile terminal. The second function optimizes the schedule of the cooking steps by using the cooking step optimization algorithm. By outputting the result into a PDF file, the user can use it at cooking. The effectiveness of these functions is confirmed through questionnaire results by 16 students in our department.

    CiNii Article

    CiNii Books

    researchmap

  • A Proposal of a Management System for Open Source Software Usage Manuals Using Content Management System

    RI Denzai, MURAKAMI Yukikazu, FUNABIKI Nobuo

    IEICE technical report   110 ( 453 )   187 - 192   2011.2

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Recently, the Open Source Software (OSS) has become used at many places. Even the installation and initial configuration of an OSS can be difficult for novice users, because there are few documents and manuals. To address this problem, we have proposed an automatic generation method of installation/configuration manuals for OSS However, this method has another problem of requiring different manuals even for the same OSS, because installation commands or configuration parameters can be different depending on OS distributions and OS/OSS versions. In this paper, we propose an OSS manual management system using a content management system "Joomla!" so that the manuals can be consolidated in a community. We implement the system composed of the four functions for general users, manual creators, community managers, and system managers, and show the effectiveness through usability evaluations using a questionnaire.

    CiNii Article

    CiNii Books

    researchmap

  • Development of an Automatic Generation System of Configuration Manuals for Open Source Software

    KAGAWA Erina, MURAKAMI Yukikazu, FUNABIKI Nobuo

    IEICE technical report   110 ( 448 )   247 - 252   2011.2

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Recently, Open Source Software (OSS) has become used at many places. However, the use of an OSS is hard for its novice users, because many OSSes have few good manuals. To solve this problem, we have proposed a method of automatically generating a web manual for installing an OSS by editing the log information recorded during the installation process by a skilled user. However, many OSS require to make changes the configuration file. In addition to that more systems are adopting OSS as middlewares such as application servers and DBMSs (Database Management Systems). For these OSS middlewares, it is known that even the processing performance is low under their default settings a great improvement is seen by optimizing their system setting. Therefore, in this research, aiming at accumulation of system optimizing technology, an automatic generation of web-based configuration manual is proposed.

    CiNii Article

    CiNii Books

    researchmap

  • An Application of the WEB Page Layout Optimization Method for Integration of Open Source Software Heterogeneous Manuals

    HORI Yuki, MURAKAMI Yukikazu, FUNABIKI Nobuo

    IEICE technical report   110 ( 448 )   241 - 246   2011.2

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Recently, the Open Source Software (OSS) has become used at many places. Even the installation and initial configuration of an OSS can be difficult for novice users, because there are few documents and manuals. To address this problem, we have proposed an automatic generation method of installation/configuration manuals for OSS. However, in the conventional system, an installation manual and a configuration manual are managed as an individual file. Therefore, the conventional system had bad convenience. We integrate an installation manual and a configuration manual and define this as an OSS usage manual. When integrate manuals, it is necessary to give a priority and to show information. When the size of a Web manual is changed by the user, a layout changes and visibility falls. In order to solve this problem, we applied to the web-page layout optimization method to proposed manuals.

    CiNii Article

    CiNii Books

    researchmap

  • A Proposal of Cooking Model and Cooking Step Scheduling Algorithm for Multiple Dishes

    MATSUSHIMA Yukiko

    IMECS 2011   127 - 131   2011

     More details

    Language:English  

    CiNii Article

    researchmap

  • An active access-point selection approach for dependable wireless mesh networks

    Nobuo Funabiki, Junki Shimizu, Masaharu Hata, Shigeru Tomisato, Toru Nakanishi, Kan Watanabe

    Journal of Interconnection Networks   12 ( 3 )   137 - 154   2011

     More details

    Authorship:Lead author   Language:English   Publisher:World Scientific Publishing Co. Pte Ltd  

    As an inexpensive, flexible, and scalable Internet-access wireless network, we have studied the architecture, protocols, and design optimizations of the Wireless Internet-access Mesh NETwork (WIMNET) that adopts multiple access-points (APs) connected through wireless links. WIMNET can improve the dependability to failures of APs and/or their links by allocating APs redundantly in the network field. Because redundant APs may increase the operational cost and degrade the throughput due to increasing radio interferences, only the necessary APs for connectivity between the hosts and the Internet gateway should be activated in communications. In this paper, we first define the active AP selection problem of selecting the minimum number of active APs, and prove the NP-completeness of its decision version through reduction from the known minimum set cover problem. Then, we propose an active AP selection algorithm of deactivating APs one by one until no more AP can be deactivated. Due to the limited transmission capacity in WIMNET, we further present an algorithm extension for throughput maximization. We verify the effectiveness of our proposal through simulations in three instances, where the number of active APs is reduced by more than 40% and the throughput is improved by more than 10% from the original in any instance. © 2011 World Scientific Publishing Company.

    DOI: 10.1142/S0219265911002915

    Scopus

    researchmap

  • An implementation of fixed backoff-time switching method on IEEE 802.11 MAC protocol for wireless Internet-access mesh network

    Nobuo Funabiki, Sritrusta Sukaridhoto, Zhe Wang, Toru Nakanishi, Kan Watanabe, Shigeto Tajima

    The 2011 International Workshop on Smart Info-Media System in Asia (SISA 2011)   67 - 72   2011

     More details

    Authorship:Lead author   Language:English  

    researchmap

  • A proposal of an active access-point selection algorithm in wireless mesh networks

    Nobuo Funabiki, Junki Shimizu, Toru Nakanishi, Kan Watanabe

    Proceedings - 2011 International Conference on Network-Based Information Systems, NBiS 2011   112 - 117   2011

     More details

    Authorship:Lead author   Language:English  

    The wireless Internet-access mesh network (WIMNET) has been studied to offer an inexpensive, scalable Internetaccess wireless network by adopting multiple access points (APs) connected by wireless links. WIMNET can improve the dependability to failures of links and/or APs by allocating APs redundantly in the network field. However, redundant APs may increase the operational cost and degrade the throughput due to increasing radio interferences. One solution to this problem is to activate only the necessary APs to provide the connectivity to the hosts while maximizing the throughput. In this paper, we first define this active AP selection problem of selecting the activated APs for communications, and propose its heuristic algorithm. The simulation results in three instances confirm the effectiveness of the proposed algorithm, and indicate the existence of an active AP selection that maximizes the throughput. Then, we present the average hop count and the traffic bias as the indices to seek the active AP selection with the maximal throughput, and the extension of our active AP selection algorithm using them. © 2011 IEEE.

    DOI: 10.1109/NBiS.2011.26

    Scopus

    researchmap

  • A smart access-point selection algorithm for scalable wireless mesh networks

    Nobuo Funabiki, Sritrusta Sukaridhoto, Masaharu Hata, Shigeru Tomisato, Toru Nakanishi, Kan Watanabe, Shigeto Tajima

    IAENG International Journal of Computer Science   38 ( 3 )   260 - 267   2011

     More details

    Authorship:Lead author   Language:English  

    researchmap

  • Efficient Proofs of Attributes in Pairing-Based Anonymous Credential System

    Amang Sudarsono, Toru Nakanishi, Nobuo Funabiki

    PRIVACY ENHANCING TECHNOLOGIES   6794   246 - 263   2011

     More details

    Language:English   Publisher:SPRINGER-VERLAG BERLIN  

    An anonymous credential system allows the user to convince a verifier of the possession of a certificate issued by the issuing authority anonymously. One of the applications is the privacy-enhancing electronic ID (eID). A previously proposed anonymous credential system achieves constant complexity in the number of finite-set attributes of the user. However, the system is based on the RSA. In this paper, we show how to achieve the constant complexity in a pairing-based anonymous credential system excluding the RSA. The key idea of the construction is the use of a pairing-based accumulator. The accumulator outputs a constant-size value from a large set of input values. Using zero-knowledge proofs of pairing-based certificates and accumulators, we can prove AND and OR relations with constant complexity in the number of finite-set attributes.

    DOI: 10.1007/978-3-642-22263-4_14

    Web of Science

    researchmap

  • An extension of active access-point selection algorithm for throughput maximization in wireless mesh networks

    Nobuo Funabiki, Junki Shimizu, Toru Nakanishi, Kan Watanabe, Shigeru Tomisato

    Proceedings - 3rd IEEE International Conference on Intelligent Networking and Collaborative Systems, INCoS 2011   367 - 372   2011

     More details

    Authorship:Lead author   Language:English  

    In order to offer an inexpensive, scalable Internetaccess wireless network, we have studied the architecture, protocols, and design optimizations of the wireless Internet-access mesh network (WIMNET) that adopts multiple access-points (APs) connected by wireless links. WIMNET can improve the dependability to failures of links and/or APs by allocating APs redundantly in the network field. Because redundant APs may increase the operational cost and degrade the throughput due to increasing radio interferences, only the necessary APs for the connectivity between the hosts and the Internet gateway should be activated in communications. Previously, we have defined the active AP selection problem of selecting the minimum number of active APs, and proposed its heuristic algorithm. However, the throughput should be maximized in WIMNET as a bandlimited wireless network, even if the number of active APs is slightly increased. In this paper, we propose the extension of the active AP selection algorithm for the throughput maximization using the average hop count. We confirm the effectiveness of our algorithm extension through simulations in three instances, where the throughput is improved by about 10% with 7-14 additional active APs on average. © 2011 IEEE.

    DOI: 10.1109/INCoS.2011.50

    Scopus

    researchmap

  • A throughput evaluation of wireless Internet-access mesh network using MIMO and adaptive array antenna

    Shigeto Tajima, Nobuo Funabiki, Shigeru Tomisato, Masaharu Hata, Teruo Higashino

    The 2011 International Workshop on Smart Info-Media System in Asia (SISA 2011)   79 - 84   2011

     More details

    Language:English  

    researchmap

  • Automatic generation of configuration manuals for open-source software

    Yukikazu Murakami, Erina Kagawa, Nobuo Funabiki

    Proceedings of the International Conference on Complex, Intelligent and Software Intensive Systems, CISIS 2011   653 - 658   2011

     More details

    Language:English  

    The installation and initial configuration of an open-source software can be difficult for novice users because of a common lack of adequate manuals. To address this problem, we have proposed a method of automatically generating Web based installation manuals for open-source software by editing the log information recorded during the installation process by a skilled user. A lot of systems using open-source software require changes of configuration files. Actually, middleware systems such as application servers and database management systems, often exhibit the low performance under their default configuration files. Thus, the optimization of such systems by setting the optimal confirmation is essential for significant performance improvements. In this paper, we propose the extension of our previous method to the automatic generation of Web-based configuration manuals. We verify the effectiveness of our proposal through experiments. © 2011 IEEE.

    DOI: 10.1109/CISIS.2011.109

    Scopus

    researchmap

  • A proposal of fixed backoff-time switching method by link activation rate for wireless mesh networks

    Shigeto Tajima, Nobuo Funabiki, Teruo Higashino

    Proceedings of the International Conference on Complex, Intelligent and Software Intensive Systems, CISIS 2011   647 - 652   2011

     More details

    Language:English  

    As an inexpensive and scalable access network to the Internet, we have extensively studied the Wireless Internet-access Mesh Network (WIMNET) that is composed of multiple access points (APs) connected through wireless links. Because most traffic in WIMNET passes through the gateway (GW) to the Internet, the links around the GW are much crowded so that they should be activated with higher priorities than others. In this paper, we propose the Fixed Back off-time Switching (CSMA-FBS) method for WIMNET using the CSMA/CA protocol to improve the performance by giving necessary activation chances to such links. Before starting communications, the target link activation rate and the active/passive back off-times for collision avoidance are calculated from the expected traffic load for each link. During communications, these back off-times are switched by comparing the actual link activation rate with the target one. By assigning different fixed values to these back off-times, the conflicts among the interfered links can be avoided. Through extensive simulations using two types of network topologies, we verify the effectiveness of our proposal. © 2011 IEEE.

    DOI: 10.1109/CISIS.2011.108

    Scopus

    researchmap

  • A proposal of a menu planning algorithm for two-phase cooking by busy persons

    Nobuo Funabiki, Shiho Taniguchi, Yukiko Matsushima, Toru Nakanishi

    Proceedings of the International Conference on Complex, Intelligent and Software Intensive Systems, CISIS 2011   668 - 673   2011

     More details

    Authorship:Lead author   Language:English  

    For busy persons such as working people, students, and nurturing parents, it is very hard to spend a long time in cooking foods by themselves at home after working for long hours on weekdays. As one solution, the cooking process can be divided into two phases, where the preparation steps for foods that they will eat on the following weekdays are performed on a weekend, and the final steps for some foods are finished on the eating day in a short time. Then, the task of generating a menu planning with this two-phase cooking becomes a complex problem to satisfy the limited cooking time. In this paper, we formulate this time-constrained menu planning problem with the two-phase cooking, and prove the NP-completeness of its decision problem through the reduction from the NP-complete knapsack problem. Then, we present its heuristic algorithm based on a simple greedy method for the knapsack problem, where foods are sequentially selected into the menu in descending order of food priorities. We apply the algorithm to the generation of one week menu plan from 53 food candidates, where the result verifies the effectiveness of our approach. © 2011 IEEE.

    DOI: 10.1109/CISIS.2011.112

    Scopus

    researchmap

  • A proposal of a traffic control method with consumed bandwidth estimation for real-time applications in wireless mesh networks

    Sritrusta Sukaridhoto, Nobuo Funabiki, Toru Nakanishi

    Proceedings of the International Symposium on Consumer Electronics, ISCE   143 - 148   2011

     More details

    Language:English  

    As a flexible and cost effective solution for a scalable Internet-access network, we have studied the Wireless Internet-access Mesh NETwork (WIMNET) that is composed of multiple access points (APs). WIMNET utilizes multi-hop communications between APs to provide access to the Internet through a gateway (GW) from associated hosts, which becomes increasingly vulnerable to problems of the available bandwidth degradation and the network latency. As a result, real-time applications such as Voice-over-IP (VoIP) and video conferences are hard in WIMNET. In this paper, we propose a traffic control method with consumed bandwidth estimation to afford real-time applications in WIMNET. After the consumed bandwidth by the requesting applications is estimated, the least priority application is repeatedly dropped at GW using the leaky bucket traffic shaping, until it does not exceed the available bandwidth in WIMNET. The effectiveness of our proposal is verified through simulations using the QualNet simulator. © 2011 IEEE.

    DOI: 10.1109/ISCE.2011.5973801

    Scopus

    researchmap

  • Minimal smart access-point selection for maximal throughput in wireless mesh networks

    Nobuo Funabiki, Tatsuya Takebayashi, Toru Nakanishi

    The International MultiConference of Engineers and Computer Scientists 2011 (IMECS 2011)   594 - 599   2011

     More details

    Authorship:Lead author   Language:English  

    researchmap

  • 無線メッシュネットワークでの動作アクセスポイント選択アルゴリズムの提案

    清水淳基, 舩曵信生, 中西透

    電子情報通信学会論文誌(B)   J94-B ( 2 )   264 - 273   2011

     More details

    Language:Japanese  

    researchmap

  • A proposal of a web-based computer-scored test assistance system for university education

    Nobuo Funabiki, Hiroki Kawano, Toru Nakanishi, Kan Watanabe

    Proceedings of the International Symposium on Consumer Electronics, ISCE   580 - 585   2011

     More details

    Authorship:Lead author   Language:English  

    Frequent applications of short tests or quizzes during classes can be effective to enhance educational effects to students in universities. However, teachers may have to spend much time to prepare test materials before classes, and mark the test papers from students after them. In this paper, in order to reduce these loads of teachers, we propose a Web-based computer-scored test assistance system that consists of the five functions for problem generation &amp
    management, test generation &amp
    management, grading, subject generation &amp
    management, and learning profile management. By handling problems and tests separately where one test is composed of several problems, this system allows users to reuse existing problems and tests in various subjects by sharing them among teachers. Besides, by automatically generating test papers containing the randomly shuffled choices for each problem, it can prevent students from cheating by peeking at test papers of other students at neighbor seats. We implemented the system by extending our learning management system called NOBASU, and applied it to one class in our department, where the questionnaire result confirms the effectiveness of the system. © 2011 IEEE.

    DOI: 10.1109/ISCE.2011.5973897

    Scopus

    researchmap

  • An implementation of a pairing-based anonymous credential system with constant complexity

    Amang Sudarsono, Toru Nakanishi, Nobuo Funabiki

    The International MultiConference of Engineers and Computer Scientists 2011 (IMECS 2011)   630 - 635   2011

     More details

    Language:English  

    researchmap

  • A Proposal of Traffic Control Method with Bandwidth Usage Estimation for Real-Time Applications in Wireless Mesh Networks

    SUKARIDHOTO Sritrusta, FUNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report   110 ( 339 )   25 - 30   2010.12

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As a flexible and cost effective solution for a large-scale Internet access network, we have studied the Wireless Internet-access Mesh NETwork (WIMNET) that is composed of multiple access points (APs). WIMNET utilizes multi-hop communications between APs to access to the Internet through a gateway (GW), which becomes increasingly vulnerable to the problems of the available bandwidth degradation and the network latency. As a result, real-time applications such as Voice-over-IP and Video conferences become hard to work in WIMNET. In this paper, we propose a traffic control method with a bandwidth usage estimation to afford real-time applications in WIMNET. After the consumed traffic is estimated, the least priority traffic is repeatedly dropped at GW using the leaky bucket traffic shaping, until it does not exceed the available bandwidth in WIMNET. The effectiveness of our proposal is verified through simulations using the QualNet simulator.

    CiNii Article

    CiNii Books

    researchmap

  • A Study of an Active Access-Point Selection Index for Throughput Maximization in Wireless Mesh Networks

    SHIMIZU Junki, FUNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report   110 ( 339 )   13 - 18   2010.12

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    The wireless Internet-access mesh network (WIMNET) has been studied to realize the inexpensive, scalable Internet-access network by composed of multiple access points (APs) connected by wireless links. WIMNET can improve the dependability to failures of links and APs by allocating APs redundantly, whereas redundant APs may cause the increase of the operational cost and the degradation of the throughput due to increasing radio interferences. Hence, we have formulated the active AP selection problem for selecting functioning APs for communications and proposed its heuristic algorithm. The simulation results indicate the existence of an active AP selection maximizing the throughput. In this paper, we present the average hop count and the traffic bias as the indices for this active AP selection with the maximum throughput. We verify their effectiveness through simulations in three instances.

    CiNii Article

    CiNii Books

    researchmap

  • An Application of the Web-Page Layout Optimization Method to Installation Manuals for Open Source Software

    HORI Yuki, MURAKAMI Yukikazu, FUNABIKI Nobuo

    IEICE technical report   110 ( 339 )   215 - 218   2010.12

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Recently, the Open Source Software (OSS) has become used at many places. However, the use of an OSS is hard for its novice users, because many OSSes have few good manuals. To solve this problem, we have proposed a method of automatically generating a web manual for installing an OSS by editing the log information recorded during the installation process by a skilled user. However, generated manuals have been designed to fit to the standard size. Many users often change a manual size to watch a manual and a terminal window together. When a manual size is small, the screen scroll operation is needed to look at the main content of the page. When the size is big, the blank space may also be large. In order to solve this problem, we applied to the web-page layout optimization method to proposed manuals.

    CiNii Article

    CiNii Books

    researchmap

  • A Proposal of Fixed Waiting Time Switching Method by Link Activation Rate in Wireless Mesh Networks

    TAJIMA Shigeto, FUNABIKI Nobuo, HIGASHINO Teruo

    IEICE technical report   110 ( 339 )   137 - 142   2010.12

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As an access network to the Internet, we have studied the Wireless Internet-access Mesh NETwork (WIMNET) that is composed of multiple access points (APs) connected with wireless links. Because most traffics pass through the gateway (GW) to the Internet, the links around the GW are crowded which should be activated with higher priorities in WIMNET. In this paper, we propose the fixed waiting time switching method based on the CSMA/CA protocol (CSMA-FWS) to improve the performance of WIMNET. Before communications, the target link activation rate and the fixed waiting times for link activation/waiting are calculated from expected traffics of each link. During communications, these waiting times are switched by evaluating the link activation rate. Besides, by assigning different values to these waiting times among the links, the conflicts among interfered links are avoided. Through simulations using two types of network topologies, we verify the effectiveness of our proposal.

    CiNii Article

    CiNii Books

    researchmap

  • Ant Colony Optimization for the Node Placement Problem

    OHKURA Keiichi, KATAYAMA Kengo, FUNABIKI Nobuo, MINAMIHARA Hideo, NISHIHARA Noritaka

    IEICE technical report   110 ( 339 )   173 - 178   2010.12

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    We address a problem of finding an optimal node placement that minimizes the amount of traffics reducing the weighted hop distances in multihop lightwave networks. The problem is called Node Placement Problem (NPP). For the NPP, several metaheuristic algorithms have been proposed so far such as genetic algorithm, tabu search, simulated annealing, iterated local search, and memetic algorithm. However, ant colony optimization (ACO) approach, one of the most representative metaheuristics, has not been presented for the NPP yet. In this paper we present an ACO algorithm incorporating k-swap local search (KLS) based on variable depth search for the NPP. To evaluate the performance of the ACO, we tested it on the benchmark problem instance of the NPP. We showed the performance of the ACO with KLS through comparisons with those of the iterated local search and the memetic algorithm that are known to be the highly effective metaheuristics for the NPP.

    CiNii Article

    CiNii Books

    researchmap

  • A Proposal of an Automatic Generation Method of Web-based Configuration Manuals for Open Source Software

    KAGAWA Erina, MURAKAMI Yukikazu, FUNABIKI Nobuo

    IEICE technical report   110 ( 339 )   209 - 214   2010.12

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Recently, Open Source Software (OSS) has become used at many places. However, the use of an OSS is hard for its novice users, because many OSSes have few good manuals. To solve this problem, we have proposed a method of automatically generating a web manual for installing an OSS by editing the log information recorded during the installation process by a skilled user. However, many OSS require to make changes the configuration file. In addition to that more systems are adopting OSS as middlewares such as application servers and DBMSs (Database Management Systems). For these OSS middlewares, it is known that even the processing performance is low under their default settings a great improvement is seen by optimizing their system setting. Therefore, in this research, aming at accumulation of system optimizing technology, an automatic generation of web-based configuration manual is proposed.

    CiNii Article

    CiNii Books

    researchmap

  • Extensions of Cooking Model for Cooking Step Optimization and Effects of Role Changes of Sub-Cook

    MATSUSHIMA Yukiko, FUNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report   110 ( 301 )   19 - 24   2010.11

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    In order to support homemade cooking of busy persons including working people, students, and child-growing families, we have proposed a cooking model to estimate the cooking time by simulating cooking steps by a main cook and a sub-cook who helps the main cook, and a cooking step scheduling algorithm using this model. In this paper, we propose extensions of the model by including additional two cooking steps, namely the nuke step and the mix step, so as to improve the accuracy of the estimated cooking time and the efficiency of the model. At the same time, we investigate effects in cooking time reductions by the increase of possible cooking steps to the sub-cook. The cooking experiment with six foods shows the improvement of the estimation accuracy, where the cooking time difference between the model and the actual cooking was about two minutes. The model calculations with various numbers of foods show that the cooking time can be reduced by the increase of possible cooking steps to the sub-cook.

    CiNii Article

    CiNii Books

    researchmap

  • Menu Selection and Bulk-Buying Ingredient Selection Algorithms for Home Cooking Support by Busy Persons

    TANIGUCHI Shiho, FUNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report   110 ( 301 )   25 - 30   2010.11

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    For busy persons such as working people and students, it is very important to reduce the time for buying ingredients and cooking foods after working for long hours on a weekday. As one solution to achieve it, they buy ingredients in bulk and finish the preparation steps of foods as the preparation phase on a weekend after planning the menus of the following weekdays. On a weekday, they only need to buy remaining ingredients and cook the finishing steps of the foods as the finishing phase that they will eat on the day, which can reduce the necessary time for home cooking. In this paper, we propose the menu planning algorithm and bulk-buying ingredient selection algorithm for this two-phase cooking. Because these problems can be reduced from the NP-complete knapsack problem, these algorithms are based on greedy methods for the knapsack problem. Through solving instances for these problems, we verify the effectiveness of the proposed algorithms.

    CiNii Article

    CiNii Books

    researchmap

  • Forward-Secure Group Signatures from Pairings

    Toru Nakanishi, Yuta Hira, Nobuo Funabiki

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E93A ( 11 )   2007 - 2016   2010.11

     More details

    Language:English   Publisher:IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

    To reduce the damage of key exposures forward secure group signature schemes have been first proposed by Song In the forward secure schemes a secret key of a group member is updated by a one way function every interval and the previous secret key is erased Thus even if a secret key is exposed the signatures produced by the secret keys of previous Intervals remain secure Since the previous forward secure group signature schemes are based on the strong RSA assumption the signatures are longer than pairing based group signatures In addition the complexity of the key update or signing/verification is O(T) where T is the total number of Intervals In this paper a forward secure group signature scheme from pairings is proposed The complexity of our key update and signing/verification is O(log T)

    DOI: 10.1587/transfun.E93.A.2007

    Web of Science

    researchmap

  • A Minimum Smart Access-Point Allocation for Maximal Throughput in Scalable Wireless Mesh Networks

    TAKEBAYASHI Tatsuya, FYNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report   110 ( 240 )   69 - 74   2010.10

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As a flexible and low-cost access network to the Internet, we have studied WIMNET (Wireless Internet-access Mesh NETwork) that is composed of multiple access-points (APs) as wireless routers. WIMNET utilizes two types of APs to achieve the scalability and the communication bandwidth while reducing the cost. One type is an expensive, PC-based smart AP (SAP) that can use multiple channels for wireless communications and has various functions for the Internet access. The other type is an inexpensive, commercial-based conventional AP (CAP) that can use only one channel. By adopting a small number of SAPs and a large number of CAPs, the large-scale WIMNET can achieve the bandwidth expansion and the cost reduction. In this paper, we propose a minimal SAP allocation algorithm for maximal throughput in WIMNET using our conventional SAP allocation algorithm. Our algorithm finds a solution that minimizes the reduction of the cost function when the number of SAPs increases. Through simulations in four instances, we show the effectiveness of our proposal.

    CiNii Article

    CiNii Books

    researchmap

  • Developments of the Node Configuration Problem for WDM Ring Networks

    ISOGAI MEGUMI, FUNABIKI NOBUO, NAKANISHI TORU

    2010 ( 3 )   1 - 8   2010.9

  • An Extension of the Cooking Step Scheduling Algorithm for Various Dishes to Two Cooks

    MATSUSHIMA Yukiko, FUNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report   110 ( 172 )   19 - 24   2010.8

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    The reduction of the cooking time with helps of partners, friends, and children is very important for busy persons. In this paper, we present the extension of the cooking step scheduling algorithm for various dishes to the case of two cooks, and the generalization of the cooking model for this extension by defining the state transition diagrams of dishes, pans and pots, a sink, stoves, and cooks, which have been proposed by our group. We implemented the algorithm as the Java application, and applied it to an instance of six dishes. The result confirmed the effectiveness of our proposal, where the case with two cooks reduced the cooking time by 16 minutes from the case with one cook.

    CiNii Article

    CiNii Books

    researchmap

  • Extensions of the Access Point Allocation Algorithm for Wireless Mesh Networks

    Walaa Hassan, Nobuo Funabiki, Toru Nakanishi

    IEICE TRANSACTIONS ON COMMUNICATIONS   E93B ( 6 )   1555 - 1565   2010.6

     More details

    Authorship:Lead author   Language:English   Publisher:IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

    Previously, we have proposed an access point (AP) allocation algorithm in indoor environments for the Wireless Internet-access Mesh NETWork (WIMNET) using one gateway (GW) to the Internet. WIMNET consists of multiple APs that are connected wirelessly mainly by the Wireless Distribution System (WDS), to expand the coverage area inexpensively and flexibly In this paper, we present two extensions of this algorithm to enhance the applicability to the large-scale WIMNET. One is the multiple GW extension of the algorithm to increase the communication bandwidth with multiple GWs, where all the rooms in the network field are first partitioned into a set of disjoint GW clusters and then, our previous allocation algorithm is applied to each GW cluster sequentially. The APs in a GW cluster share the same GW. The other is the dependability extension to assure the network function by maintaining the connectivity and the host coverage, even if one link/AP fault occurs, where redundant APs are added to the AP allocation by our previous algorithm. The effectiveness of our proposal in terms of the number of APs and the throughput is verified through simulations using the WIMNET simulator.

    DOI: 10.1587/transcom.E93.B.1555

    Web of Science

    researchmap

  • A prioritized link activation method for access-point communications in wireless mesh networks

    TAJIMA Shigeto, FUNABIKI Nobuo, HIGASHINO Teruo

    IEICE technical report   110 ( 4 )   47 - 52   2010.4

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As a flexible, inexpensive access network to the Internet, we have studied the Wireless Internet-access Mesh NETwork (WIMNET) that is composed of multiple access points (APs) connected with wireless links. Because most traffics pass through the gateway (GW) to the Internet, the links around the GW are crowded and can become bottlenecks in WIMNET. In this paper, we propose the prioritized link activation method based on the TDMA protocol to improve the performance of WIMNET. At each time slot, the links scheduled there are activated if they have packets. Then, other links are sequentially activated in descending order of priorities given by the traffics, if they have packets and do not cause interferences. Through simulations using two types of network topologies, we verify the effectiveness of our proposal.

    CiNii Article

    CiNii Books

    researchmap

  • A WDS Clustering Algorithm for Wireless Mesh Networks

    Shigeto Tajima, Nobuo Funabiki, Teruo Higashino

    IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS   E93D ( 4 )   800 - 810   2010.4

     More details

    Authorship:Lead author   Language:English   Publisher:IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

    Wireless mesh networks have been extensively studied as expandable. flexible. and inexpensive access networks to the Internet This paper focuses on one composed of multiple access points (APs) connected through multihop wireless communications mainly by the wireless distribution system (WDS) For scalability, the proper partition of APs into multiple WDS clusters is essential, because the number of APs in one cluster is hinted due to the increasing radio interference and control packets In this paper, we formulate this WDS clustering problem and prove the NP-completeness of its decision version through reduction from a known NP-complete problem Then we propose its heuristic algorithm. using a greedy method and a variable depth search method. to satisfy the complex constraints while optimizing the cost function We verify the effectiveness of our algorithm through extensive simulations. where the results confirm as superiority to the existing algorithm in terms of throughput.

    DOI: 10.1587/transinf.E93.D.800

    Web of Science

    researchmap

  • Test Code Assignment Function in Java Programming Education Support System Using Test-Driven Development Method

    FUKUYAMA YUKI, FUNABIKI NOBUO, NAKANISHI TORU, AMANO NORIKI

    2010 ( 21 )   1 - 8   2010.2

  • A Proposal of the Active Access Point Selection Algorithm for Wireless Internet-access Mesh Networks

    SHIMIZU Junki, FUNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report   109 ( 421 )   7 - 12   2010.2

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As a scalable, inexpensive Internet-access network, we have studied the wireless Internet-access mesh network (WIMNET) that is composed of multiple access points (APs) connected by wireless links. WIMNET can improve the dependability to failures of links and APs by allocating APs redundantly. However, redundant APs may cause the increase of the operational cost and the degradation of the communication performance due to increasing radio wave interferences. In this paper, we formulate the active AP selection problem for selecting functioning APs for communications, and propose its algorithm. After finding the communication path using all the APs, our algorithm seeks the minimization of active APs by repeating the removal of one active AP and the check of the path existence. Through simulations using the WIMNET simulator, we show that our algorithm can reduce the number of active APs and there exists the best number of active APs in terms of the throughput.

    CiNii Article

    CiNii Books

    researchmap

  • Revocable Group Signature Schemes with Constant Costs for Signing and Verifying

    Toru Nakanishi, Hiroki Fujii, Yuta Hira, Nobuo Funabiki

    IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES   E93A ( 1 )   50 - 62   2010.1

     More details

    Language:English   Publisher:IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

    Lots of revocable group signature schemes have been proposed so far. In one type of revocable schemes, signing and/or verifying algorithms have O(N) or O(R) complexity, where N is the group size and R is the number of revoked members. On the other hand, in Camenisch-Lysyanskaya scheme and the followers, signing and verifying algorithms have O(1) complexity. However, before signing, the updates of the secret key are required. The complexity is O(R) in the worst case. In this paper, we propose a revocable scheme with signing and verifying of O(1) complexity, where any update of secret key is not required. The compensation is the long public key of O(N). In addition, we extend it to the scheme with O( root N)-size public key, where signing and verifying have constant extra costs.

    DOI: 10.1587/transfun.E93.A.50

    Web of Science

    researchmap

  • Anonymous IEEE802.1X authentication system using group signatures

    Amang Sudarsono, Toru Nakanishi, Yasuyuki Nogami, Nobuo Funabiki

    Journal of Information Processing Society Japan   51 ( 3 )   691 - 702   2010

     More details

    Language:English  

    researchmap

  • A Node Aggregation Approach for WDM Ring Networks

    Nobuo Funabiki, Toru Nakanishi, Megumi Isogai

    TENCON 2010: 2010 IEEE REGION 10 CONFERENCE   829 - 834   2010

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    For a high-speed metropolitan area network (MAN), a ring network based on the wavelength-division multiplexing (WDM) technology has been deployed to solve global information explosions in the Internet. To enhance the network performance, we have studied the node configuration problem, particularly for the one with the double-ring architecture where each node is equipped with fast-tunable transmitters and wavelength-fixed receivers (TT-FR) as fiber interfaces. In our studies, by adopting additional transmitters/receivers, nodes can afford far larger traffics than conventional ones. This fact indicates that plural nodes should be aggregated into one so that the transmitters/receivers can be utilized more efficiently. This paper presents a definition of the node aggregation problem for the WDM ring network and its simple greedy heuristic algorithm. The simulation results using the network simulator show the effectiveness of our approach.

    DOI: 10.1109/TENCON.2010.5686576

    Web of Science

    researchmap

  • An extension of the web-page layout optimization method for multimodal browsing sizes

    Nobuo Funabiki, Junki Shimizu, Megumi Isogai, Toru Nakanishi

    Proceedings - 13th International Conference on Network-Based Information Systems, NBiS 2010   139 - 146   2010

     More details

    Authorship:Lead author   Language:English  

    Recently, Web-page browsings at various terminals have become popular due to deployments of small mobile devices and large flat displays. To deal with this recent trend, we have proposed a Web-page layout optimization method for multimodal browsing sizes. It dynamically changes box locations and font sizes by switching CSS files for different browsing sizes, so that the main content can be accessed without the screen scroll operation even at a small size whereas the blank space is avoided at a large size. However, in this method, any box location must be specified by the absolute value in HTML/CSS files, which is not easy under a variety of browsing sizes. In this paper, we propose the extension of this method for flexible Web-page designs using the normal flow, the liquid layout, and the float property, where the browser automatically arranges the boxes. Using Ajax, the box location and the font size is switched to fit to the current browsing size by our method. The effectiveness of our proposal is verified through a usability test using sample Web-pages at small sizes. © 2010 IEEE.

    DOI: 10.1109/NBiS.2010.18

    Scopus

    researchmap

  • Software architecture and characteristic functions in learning management system "NOBASU"

    Nobuo Funabiki, Toru Nakanishi, Noriki Amano, Hiroki Kawano, Yuuki Fukuyama, Megumi Isogai

    Proceedings - 2010 10th Annual International Symposium on Applications and the Internet, SAINT 2010   109 - 112   2010

     More details

    Authorship:Lead author   Language:English  

    Recently, a learning management system (LMS) using the Web technology has been used at many educational institutions. To support educational activities in our department, we have independently developed an LMS called NOBASU (NetwOrk-Based Assistant System for University education) to improve the quality while reducing costs. Besides conventional functions in LMS, NOBASU has incorporated several original ones such as the keyword submission function for preparing and reviewing class contents. In this paper, we present two new characteristic functions for the Java programming education in NOBASU. The Java code test function verifies the specifications in source codes from students using the test-driven development (TDD) method. The Java test code submission function requests students to submit test codes so that they can generate detailed program specifications by themselves. © 2010 IEEE.

    DOI: 10.1109/SAINT.2010.24

    Scopus

    researchmap

  • A Proposal of a Smart Access Point Allocation Algorithm for Scalable Wireless Mesh Networks

    Kanako Uemura, Nobuo Funabiki, Toru Nakanishi

    INTERNATIONAL MULTICONFERENCE OF ENGINEERS AND COMPUTER SCIENTISTS (IMECS 2010), VOLS I-III   848 - 853   2010

     More details

    Authorship:Lead author   Language:English   Publisher:INT ASSOC ENGINEERS-IAENG  

    As a flexible, inexpensive, and extensive Internet access network, we have studied WIMNET (Wireless Internet-access Mesh NETwork) composed of multiple access points (APs) as wireless mesh routers. WIMNET utilizes two types of APs to achieve the scalability with sufficient bandwidth while reducing costs. One is the expensive, programmable smart AP (SAP) that can use plural channels for wireless communications and has various functions for the Internet access. Another is the inexpensive, non-rogrammable conventional AP (CAP) that can use only one channel. To enhance the performance, the proper SAP allocation is critical, because the number of SAPs is much smaller than that of CAPs. In this paper, we present the definition of the SAP allocation problem, and its algorithm of extracting the optimum solution in terms of the newly defined cost function after finding the communication route configuration by applying our previous algorithms. We verify the effectiveness through simulations in three network topologies using the WIMNET simulator.

    Web of Science

    researchmap

  • Software Architecture and New Functions in Learning Management System "NOBASU"

    Nobuo Funabiki, Toru Nakanishi, Noriki Amano, Hiroki Kawano, Kanako Uemura

    INTERNATIONAL MULTICONFERENCE OF ENGINEERS AND COMPUTER SCIENTISTS (IMECS 2010), VOLS I-III   665 - 670   2010

     More details

    Authorship:Lead author   Language:English   Publisher:INT ASSOC ENGINEERS-IAENG  

    Recently, the learning management systems (LMS) using the Web technology has been developed and used at a lot of educational institutions. We have continuously developed an original LMS called NOBASU (NetwOrk-Based Assistant System for University education) to support various educational activities in our department to improve the quality while reducing costs. In this paper, we describe the software architecture and the outline of distinguishing functions in NOBASU. In addition to conventional functions in LMS, NOBASU has incorporated several original ones such as the keyword submission function for preparing and reviewing classes, the lecture-scene playback function using the digital picture-card show, and the writing style check function for report submissions. We have implemented them in NOBASU and evaluated the effectiveness through applications to real classes in our department.

    Web of Science

    researchmap

  • A Proposal of a Cooking Order Optimization Algorithm of Various Menus

    MATSUSHIM YUKIKO, FUNABIKI NOBUO, NAKANISHI TORU

    2009 ( 13 )   1 - 6   2009.12

  • Improvement of Dependable Access Point Allocation Algorithm and Introduction of Route Availability for Wireless Mesh Networks

    HASSAN Walaa, FARAG Tamer, FUNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report   109 ( 326 )   11 - 16   2009.12

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As a scalable, flexible, and inexpensive network, we have studied the wireless Internet-access mesh network (WIMNET) that is composed of multiple access points (APs) connected by the wireless distribution system (WDS). Previously, we have proposed the AP allocation algorithm, and its dependability extensions such that one link fault or one AP fault does not impair the connectivity of the network. In this paper, we improve this heuristic algorithm by adding the improvement stage using the local search method. Besides, we introduce the route availability (RA) index to estimate the certainty of connections between hosts and the Internet gateway. We verify the effectiveness of our proposal through simulations in two instances.

    CiNii Article

    CiNii Books

    researchmap

  • A Proposal of Efficient Attribute-Based Group Signature Schemes Using Pairings

    FUJII Hiroki, NAKANISHI Toru, FUNABIKI Nobuo

    IEICE technical report   109 ( 271 )   15 - 22   2009.11

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Group signature scheme is the digital signature scheme enhancing the privacy of the user, and efficient pairing-based schemes have been proposed. Recently, some attribute-based group signature schemes are proposed, where the signer's attributes can be verified. The attribute-group signature allows us to construct more complex groups, because it can prove the logical relation of attributes such as 'AND' and 'OR'. However, the previouse schemes, the number of pairings and exponentiations in signing and verification depends on the number of attributes. In this paper, we propose an efficient attribute-base group signature scheme, where the computational complexity doesn't depend on the number of attributes.

    CiNii Article

    CiNii Books

    researchmap

  • A Proposal of a Smart Access Point Allocation Algorithm for Scalable Wireless Mesh Networks

    UEMURA Kanako, FUNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report   109 ( 228 )   13 - 18   2009.10

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    For a flexible and low-cost access network to the Internet, we have studied WIMNET (Wireless Internet-access Mesh NETwork) that is composed of multiple access points (APs) as wireless routers. WIMNET utilizes two types of APs to achieve the scalability and the communication bandwidth while reducing the cost. One type is the expensive, note-PC based smart AP (SAP) that can use multiple channels for wireless communications and has various functions for the Internet access. Another type is the inexpensive, commercial-based conventional AP (CAP) that can use only one channel. For the performance enhancement, the proper allocation of SAPs among APs is critical in WIMNET, because the number of SAPs is usually much smaller than that of CAPs. In this paper, we present the formulation of the SAP allocation problem for WIMNET and its heuristic algorithm. Our algorithm seeks the best SAP allocation in terms of the newly defined cost function, after finding the communication route by applying our previous algorithms. We verify the effectiveness of our proposal through simulations in three instances using the WIMNET simulator.

    CiNii Article

    CiNii Books

    researchmap

  • A node configuration algorithm with bandwidth bottleneck resolution for WDM ring networks

    Megumi Isogai, Nobuo Funabiki, Toru Nakanishi, Yosuke Isshiki

    PHOTONIC NETWORK COMMUNICATIONS   18 ( 2 )   218 - 226   2009.10

     More details

    Language:English   Publisher:SPRINGER  

    The wavelength-division multiplexing (WDM) technology has been extensively studied and actually deployed as a key technology to solve global information explosions by multiplexing plural signal paths using different wavelengths into one optical fiber. Among WDM-based network architectures, this article focuses on a double-ring one for a next-generation metropolitan area network (MAN), where each node is normally equipped with two pairs of fast-tunable transmitters and wavelength-fixed receivers (TT-FR) as interface to two fibers. To enhance the network performance, additional transmitters/receivers at nodes and receiver wavelengths should be assigned optimally, so that the bandwidth bottleneck can be resolved both on nodes and fiber links. This article formulates this node configuration problem with bandwidth bottleneck resolution as a combinatorial optimization problem, and proves the NP-completeness of its decision version. Then, it presents the two-phase heuristic algorithm composed of a greedy method and a variable depth search (VDS) method. Our algorithm is evaluated through extensive network simulations, where the results support the effectiveness of this joint assignment approach.

    DOI: 10.1007/s11107-009-0185-y

    Web of Science

    researchmap

  • Improvement of Anonymous Authentication System Using Proxies and Its Application to an Anonymous Bulletin Board

    YANO Masaya, NAKANISHI Toru, FUNABIKI Nobuo

    IEICE technical report   109 ( 207 )   45 - 50   2009.9

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Our research group has implemented the anonymous authentication system based on a group signature scheme for Web services. To avoid modifications of Web servers and browsers, this system uses proxies. However, the system has problems that the lack of the session management causes the communication delay, and that any application of the system has not been implemented, yet. In this study, we implemented the session management function and applied it to an anonymous bulletin board. The experimental results show that the communication time is reduced in a session due to the session management and that the anoymous bulletin board is available in practical time.

    CiNii Article

    CiNii Books

    researchmap

  • An accessibility improvement in the Web-page layout optimization method for adapting to browsing size

    ISOGAI Megumi, FUNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report   109 ( 160 )   81 - 86   2009.7

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    CiNii Article

    researchmap

  • A Proposal of an Educational-support System for Java Programming Using the Test-driven Development Method

    MATSUSHIMA Yukiko, KASAI Yasuhiro, FUNABIKI Nobuo, NAKANISHI Toru, AMANO Noriki

    IEICE technical report   109 ( 82 )   7 - 12   2009.6

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    This paper presents an educational-support system for Java programming using the test-driven development method, with the goals of reducing the teacher load in evaluating program codes submitted from students and giving corrections and comments to them, and improving the student learning environments. To achieve our goals, this system adopts a Java program verification tool called JUnit, and can generate the test code to verify the student codes from the model code to the assignment made by the teacher in a semi-automatic way. By providing the test code to students as the code specification in the assignment, the verification accuracy is enhanced with reduction of the ambiguity in code implementations. The questionnaire results from both teachers and students confirm the effectiveness of the proposed system in the Java programming education.

    CiNii Article

    CiNii Books

    researchmap

  • An Implementation of a Group Signature Scheme with Efficient Verifier-Local Revocation Check

    SUDARSONO Amang, NAKANISHI Toru, SAKEMI Yumi, NOGAMI Yasuyuki, FUNABIKI Nobuo

    IEICE technical report   109 ( 42 )   37 - 42   2009.5

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    A group signature scheme with efficient verifier-local revocation check has been proposed. This scheme provides a more efficient revocation check, using the multi-pairing technique for a product of pairings. However, this scheme has not been implemented and evaluated. This paper presents an implementation of the group signature scheme and the experimental results.

    CiNii Article

    CiNii Books

    researchmap

  • A Generalized Access Point Allocation Algorithm for Wireless Mesh Networks in Indoor Environments

    FARAG Tamer, FUNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report   109 ( 36 )   31 - 36   2009.5

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Previously, we have proposed an access point (AP) allocation algorithm in indoor environments for the Wireless Internet-access Mesh NETwork (WIMNET) with one gateway (GW) to the Internet. WIMNET is composed of multiple APs that are connected with wireless links, mainly using the wireless distribution system (WDS). In this paper, we generalize this algorithm to handle multiple GWs in the field that are essential for the large scale WIMNET. The generalized algorithm first divides the rooms in the network field into a set of GW clusters by two steps, initial greedy clustering and clustering search improvement. Where the APs allocated in the rooms of the same cluster are connected to the same GW. Then, the previous AP allocation algorithm is applied to the rooms in each cluster sequentially. The effectiveness of our proposal is verified through extensive simulations using the WIMNET simulator.

    CiNii Article

    CiNii Books

    researchmap

  • Dependability Extensions of the Access Point Allocation Algorithm for Wireless Mesh Networks

    HASSAN Walaa, FARAG Tamer, FUNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report   109 ( 36 )   37 - 42   2009.5

     More details

    Language:English   Publisher:The Institute of Electronics, Information and Communication Engineers  

    As a scalable, flexible, and inexpensive network, we have studied the wireless Internet-access mesh network (WIMNET) that is composed of multiple access points (APs) connected by the wireless distribution system (WDS). WIMNET may suffer from failures of links or APs due to hardware faults or network environmental changes. In this paper, we propose dependability extensions to link/AP faults of the AP allocation algorithm for WIMNET in indoor environments that has been proposed by our group. The extended algorithm finds AP allocations where even if one link/AP is failed, the connectivity of the APs is maintained, while seeking the minimization of the number of additional APs and the maximization of the performance. The effectiveness of our proposal is verified through simulations using the WIMNET simulator.

    CiNii Article

    CiNii Books

    researchmap

  • An Access Point Allocation Algorithm for Indoor Environments in Wireless Mesh Networks

    Tamer Farag, Nobuo Funabiki, Toru Nakanishi

    IEICE TRANSACTIONS ON COMMUNICATIONS   E92B ( 3 )   784 - 793   2009.3

     More details

    Language:English   Publisher:IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG  

    As a flexible, cost effective solution for a large-scale access network to the Internet, we have studied the design optimization of the Wireless Internet-access Mesh NETwork (WIMNET). WIMNET consists of multiple access points (APs) that have wireless links between them mainly on the wireless distribution system (WDS). In WIMNET, the links around the Internet gateway can be bottlenecks because every packet passes through it after multihop link activations. Besides, the link quality may be degraded by obstacles in indoor environments. Thus, the proper allocation of APs is essential in WIMNET, so that the communication quality should be ensured while the installation and management cost be minimized. In this paper, we formulate this AP allocation problem for indoor environments in WIMNET with the proof of the NP-completeness of its decision version. Then, we present its two-stage heuristic algorithm composed of the initial greedy allocation and the iterative improvement. The effectiveness of our proposal is verified through extensive simulations in three indoor environments.

    DOI: 10.1587/transcom.E92.B.784

    Web of Science

    researchmap

  • An Online Check Function of Writing Style in the Learning Management System "NOBASU"

    KAWANO Hiroki, FUNABIKI Nobuo, NAKANISHI Toru, AMANO Noriki

    IEICE technical report   108 ( 470 )   169 - 174   2009.2

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Our research group has developed an original Learning Management System (LMS) named NOBASU to improve educational services to students in our department. This paper presents an online check function of writing style on NOBASU. This function checks the writing styles of "Rhetoric", "Report Length" and "Keywords" in students' reports, and quickly provides results to them. The latest list of frequently used words selected from all submitted reports are also shown. To evaluate efficiency of this function, we implemented and applied it to a lecture in our department. According to the questionnaire survey, we found the effectiveness for students in learning writing styles.

    CiNii Article

    CiNii Books

    researchmap

  • A WEB Database System for Managing Open Source Software Installation Manuals

    MURAKAMI Yukikazu, KAN Etsu, FUNABIKI Nobuo, NAKANISHI Toru, TOKUNAGA Hidekazu, SHIGETA Kazuhiro

    IEICE technical report   108 ( 470 )   163 - 168   2009.2

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Recently, the Open Source Software (OSS) has become used at many places. However, the use of an OSS is hard for its novice users, because many OSSes have few good manuals, and the installation of an OSS package sometimes requires installations of multiple OSS packages to be integrated together. To solve this problem, we have proposed a method of automatically generating a WEB manual for installing an OSS by editing the log information recorded during the installation process by a skilled user. This method has a problem of requiring different manuals even for the same OSS, because installation commands may be different depending on the OS distribution for the PC and the OS/OSS versions. It is impossible to create all the manuals to cover any difference. In this paper, we propose a WEB database system for managing installation manuals so that skilled OSS users can easily upload new manuals for OSSes with new versions, and the similar manual display function after investigating differences of installation commands under different OS/OSS versions and OS distributions.

    CiNii Article

    CiNii Books

    researchmap

  • Improvements in the WDS Clustering Algorithm for Wireless Internet-access Mesh Networks

    TAJIMA Shigeto, FUNABIKI Nobuo, HIGASHINO Teruo

    IEICE technical report   108 ( 457 )   343 - 348   2009.2

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    We have studied the Wireless Internet-access Mesh NETwork (WIMNET) as a large-scale multihop wireless network using Wireless Distribution System (WDS) for Internet access network. We have proposed the heuristic algorithm for the WDS clustering problem to achieve the scalable WIMNET. In this paper, we propose the four improvements of our algorithm; 1) consideration of total hop counts and total interferences in the cost function, 2) random selection of starting APs, 3) modification of the cost function for the gateway AP selection, and 4) consideration of interferences for the route selection. Through simulations using two types of network topologies, we verify the effectiveness of these improvements.

    CiNii Article

    CiNii Books

    researchmap

  • A Multi-Server Video Encoding System Using Divided Video Files at Scene Changes

    OKADA Genya, FUNABIKI Nobuo, NAKANISHI Toru

    IEICE technical report   108 ( 392 )   79 - 82   2009.1

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Recently, with spread of high-performance personal computers and broadband networks, the use of video contents has become popular. As a result, the fast encoding process of video files is very important to improve the convenience of video contents. In this paper, we present a multi-server video encoding system to speed up the encoding process by dividing one video file into multiple fragments and encoding them in parallel using multiple servers. To improve the quality of the reunited video file, we divide the source video file at scene changes of the content. We have implemented the proposed system, and confirmed that our system using three servers can reduce the encoding process time into the half of the single server case.

    CiNii Article

    CiNii Books

    researchmap

  • A Proposal of an Web Page Layout Optimization Method for Various Browser Sizes

    ISSHIKI Yosuke, FUNABIKI Nobuo, NAKANISHI Toru, ISOGAI Megumi

    IEICE technical report   108 ( 392 )   83 - 88   2009.1

     More details

    Language:Japanese   Publisher:The Institute of Electronics, Information and Communication Engineers  

    Recently, the opportunity of Web browsing using terminals with various sizes has increased due to the development of a variety of terminals. Unfortunately, most Web pages have been designed to be fit to terminals with the standard size. As a result, the screen scroll operation is necessary to access the main content at a small-size terminal, whereas the blank space becomes large at a large-size terminal. In this paper, we focus on the separation of the document structure description by an XHTML file and the appearance description by a CSS file. Then, we propose a method of delivering the Web page layout fit to the browsing size. This method first generates the CSS file fit to each size automatically from the Web page files that have been produced by a user for the standard size. Then, it dynamically changes the CSS file using JavaScript. We confirm the effectiveness of our proposal at various sizes by generating an Web page using this method.

    CiNii Article

    CiNii Books

    researchmap

  • Revocable Group Signature Schemes with Constant Costs for Signing and Verifying

    Toru Nakanishi, Hiroki Fujii, Yuta Hira, Nobuo Funabiki

    PUBLIC KEY CRYPTOGRAPHY-PKC 2009, PROCEEDINGS   5443   463 - 480   2009

     More details

    Language:English   Publisher:SPRINGER-VERLAG BERLIN  

    Lots of revocable group signature schemes have been proposed so far. In one type of revocable schemes, signing and/or verifying algorithms have O(N) or O(R) complexity, where N is the group size and It is the number of revoked members. On the other hand, in Camenisch-Lysyanskaya scheme and the followers, signing and verifying algorithms have O(1) complexity. However, before signing, updates of the secret key are required. The complexity is O(R) in the worst case. In this paper, we propose a revocable scheme with signing and verifying of O(1) complexity, where no updates of secret key are required. The compensation is the long public key of O(N). In addition, we extend it to the scheme with O(root N)-size public key, where signing and verifying have constant extra costs.

    DOI: 10.1007/978-3-642-00468-1_26

    Web of Science

    researchmap

  • A Proposal of Structured Learning Assistance Function in Lecture-Scene Playback System Using Digital Picture-Card Show

    Nobuo Funabiki, Aki Mouri, Kanako Uemura, Toru Nakanishi

    CISIS: 2009 INTERNATIONAL CONFERENCE ON COMPLEX, INTELLIGENT AND SOFTWARE INTENSIVE SYSTEMS, VOLS 1 AND 2   983 - 988   2009

     More details

    Authorship:Lead author   Language:English   Publisher:IEEE  

    The Web-based lecture-scene playback system using the digital picture-card show has been studied to improve the educational quality of lectures with computer-aided slide presentations in universities. In this system, fine still images of lecture scenes, containing the lecturer the blackboard, and the presentation screen, are periodically taken by a commercial digital photo camera, and the lecturer voice is recorded into a digital file by a personal computer during a class. Then, the digital picture-card show to play back the lecture scenes is edited by selecting one image and the voice file section corresponding to one lecture scene that is defined as the time span of teaching one slide page by the lecturer The picture-card show is delivered to students through the World-Wide Web system on demand. In this paper we propose the structured learning assistance function for this lecture-scene playback system, so that students can study important technical concepts in the lecture structurally This function classifies the lecture scenes corresponding to one concept into five structures, and generates the links between them automatically. Through applications to one course for freshmen in our department, we show the effectiveness of our proposal.

    DOI: 10.1109/CISIS.2009.103

    Web of Science

    researchmap

  • 操作ログを用いたオープンソースソフトウエアのインストールマニュアル自動生成法の提案

    村上幸一, 舩曵信生, 徳永秀和, 重田和弘, 中西透

    情報処理学会論文誌   50 ( 3 )   926 - 939   2009

     More details

    Language:Japanese  

    researchmap

  • A web-based installation manual management system for open source software

    Yukikazu Murakami, Nobuo Funabiki, Hidekazu Tokunaga, Kazuhiro Shigeta, Toru Nakanishi

    NCM 2009 - 5th International Joint Conference on INC, IMS, and IDC   1261 - 1266   2009

     More details

    Language:English  

    Recently, Open Source Software (OSS) has become commonly used at many places. Unfortunately, although the use of OSS is often hard for novice users, many OSSes have few good manuals. To solve this problem, we have proposed a method of automatically generating a Web-based installation manual for an OSS by editing the log information recorded during the installation process by a skilled user. However, this method has another problem of requiring several manuals even for the same OSS, because installation commands may be different depending on the installation environment such as Linux distributions and versions. In addition, novice users sometimes make input mistakes during installation process that cannot be detected by themselves. In this paper, we propose a Web-based system to manage the created manuals so that users can easily use them. By incorporating the analogous manual search algorithm after investigating command changes under different environments, our system is able to show similar manuals if no existing manual matches to the search condition. Besides, we propose the installation guidance function to avoid mistakes by users. It monitors the input commands by a user, and displays the correct commands with the error message if a mistake is found. The experimental results in installing OSS packages by novice users confirm the effectiveness our proposal. © 2009 IEEE.

    DOI: