Faculty Profiles - Shimayoshi Takao

透過型SMTPプロキシによるメール送信集約とキュー輻輳回避の検討 Reviewed

心筋虚血・再灌流の数理モデル解析

松岡達, 嶋吉隆夫, 竹内綾子

日本生理学雑誌 84 ( 1 ) 7 - 7 2022.2

小田, 知央, 廣川, 優, 近藤, 宇智朗, 嶋吉, 隆夫, 笠原, 義晃

マルチメディア，分散協調とモバイルシンポジウム2021論文集 2021 ( 1 ) 1479 - 1485 2021.6

Language：Japanese Publisher：情報処理学会

電子メールは古くから用いられているメッセージ交換手段で，依然として世界的に広く利用されている．メールサービスを提供するメールホスティングでは，多数の利用者を同一システムに収容するマルチテナント型によりリソース効率を高め，運用コストを低減している．メールホスティングでは利用可能なグローバル IP アドレス数やメール送信の集中管理のため送信サーバは集約されていることが多いが，大量メール送信や送信先の迷惑メール対策により送信キューの輻輳が発生することで，問題を起こしたテナント以外にも影響が波及し，サービス品質の低下や管理コストの増大をまねいている．本研究では，テナントごとの送信キューの分離と，メール送信の集中管理や送信用グローバル IP アドレスの管理を両立する，メール送信集約用の透過型 SMTP プロキシを提案する．また，送信キューの分離によってキュー輻輳時の影響範囲が限定される効果を確認するための予備実験と，透過型 SMTP プロキシのプロトタイプ実装について述べる．

A Supplementation Method for Delegation of Address Management on a Cloud Email Service Reviewed

Other Link： http://hdl.handle.net/2324/4753053

62 ( 3 ) 810 - 817 2021.3

Authorship：Lead author,　Corresponding author Language：Japanese Publishing type：Research paper (scientific journal)

In providing organizational email service, the use of cloud email services contributes to reducing operation and management costs, generally. In most cloud email services, the management of a certain part of email addresses is not delegatable to administrators of organizational units, but this causes operational load concentration on organizational service administrators in large-scale organizations. For solving this issue, this study aims to enable delegations of email address management to administrators of organizational units. This article introduces a method for delegation of email address management and a supplemental system onto a cloud email service. The proposed method divides the management of email addresses within internet subdomains for organizational units from account administration and delegates the email address management to subdomain administrators. The present system for email address management is designed based on microservice architecture and configured in serverless. This microservice architecture and serverless configuration reduces operation and management costs and contributes to the maintainability and extensibility of the present system. Furthermore, the use of an identity-as-a-service for authentification, authorization and storing privilege information ensures confidentiality and security of system accounts.

CiNii Books

Challenge for Consolidation of Individual Email Services into a Cloud Service Reviewed

Takao Shimayoshi, Yoshiaki Kasahara, Naomi Fujimura

Proceedings ACM SIGUCCS User Services Conference 26 - 29 2021.3

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (international conference proceedings) Publisher：ACM

Email is a traditional but still important global communication tool. An email address is a kind of personal identifier, and email addresses printed on publications require persistent reachability. Kyushu University provides a university-wide email service, Primary Mail Service, and assigns a Primary Mail Address for each member. Divisions of the university additionally operate individual email services for their internet subdomains and administer member email addresses. Since email is a major means of cyberattacks nowadays, the secure operation of an email server demands considerable effort and high skill. This article describes a challenge at Kyushu University for consolidating individual email services. Since 2018, the Primary Mail Service has been operated using Microsoft's cloud service, Exchange Online, which supports multiple internet domains on a tenant. The approach employed is registering divisional subdomains to the tenant and configuring forwarding addresses from addresses of the subdomains to the Primary Mail Addresses or external addresses. A desirable scheme is for each domain administrator to manage forwarding addresses of the domain, but Exchange Online is unable to delegate administration to the domains. To overcome this, a system was designed and developed for domain administrators to create, read, update, and delete forwarding addresses. Beginning in July 2020, a new service to import divisional domains was offered. We are now planning measures for promoting the consolidation of individual email services.

DOI： 10.1145/3419944.3441170

Other Link： https://dblp.uni-trier.de/db/conf/siguccs/siguccs2021.html#ShimayoshiKF21

Renovation of the Office 365 environment in Kyushu University: Integration of account management and authentication Reviewed International journal

Takao Shimayoshi, Yoshiaki Kasahara, Naomi Fujimura

Proceedings ACM SIGUCCS User Services Conference 135 - 139 2019.10

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (international conference proceedings) Publisher：ACM

Office 365 Education is a suite of cloud services for students and educators. Kyushu University has provided Office 365 accounts for all students and staff. The first generation of an environment for Office 365 provisioning in the university had several issues about associating between Office 365 accounts and member identifications of the university. All university members are randomly assigned unique identifiers by the central ID management system for using commonly in university-wide information services. Since the IDs are for internal use only, the first environment authenticated a user with another ID and password specific for Office 365. In addition, processes for assigning licenses and giving privilege to users of Office 365 depending on modifications to member information in the ID management system were not fully automated. This paper shows how we resolved problems integrating Office 365 into the ID management of the university by rebuilding the infrastructure. We configured a federated authentication system and developed a system for processing in events of the account life cycle.

DOI： 10.1145/3347709.3347819

Other Link： https://dblp.uni-trier.de/db/conf/siguccs/siguccs2019.html#ShimayoshiKF19

Migrate legacy email services in Kyushu university to exchange online Reviewed International journal

Yoshiaki Kasahara, Takao Shimayoshi, Tadayuki Miyaguchi, Naomi Fujimura

Proceedings ACM SIGUCCS User Services Conference 127 - 131 2019.10

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

In Kyushu University, Information Infrastructure Initiative provides an email service for students and staff members, called “Primary Mail Service”. We had operated an on-premises system for this service, and the lifetime of this system would end in early 2019. We needed to reduce costs for replacing this system because our university had just finished a major campus migration. We compared some options such as building a yet another on-premise system and migrating to a cloud-based email service and finally gave up the on-premise option because we couldn’t afford replacement and operational costs of another on-premises system anymore. We selected Microsoft Exchange Online as the new service mainly because we already had a contract with Microsoft and been operating an Office 365 tenant. We had additional requirements for user provisioning and services which were not available in Exchange Online, so we had to implement and maintain additional systems on top of it. On December 18th, 2018, we successfully migrated the email service to Exchange Online. By coincidence, Kyushu University Administration Bureau decided to migrate their in-house Exchange server to Exchange Online. After some discussions, they concluded to migrate their domain to the same tenant with Primary Mail Service. Other than that, there are more than a hundred legacy email servers inside our campus network operated by various departments as subdomains of kyushu-u.ac.jp. We are designing a plan to consolidate them into our tenant of Exchange Online to reduce a budget and human resource costs, and to improve security. In this presentation, we share our experiences about migrating our campus-wide email services to Exchange Online. We also discuss why we want to consolidate other legacy email servers and how to implement the plan.

DOI： 10.1145/3347709.3347817

A Study on Confidential Information Protection in Kyushu University

Other Link： https://dblp.uni-trier.de/db/conf/siguccs/siguccs2019.html#KasaharaSMF19

Parameter Uncertainty Analysis of a Mathematical Ion Channel Model Reviewed International journal

Takao Shimayoshi

Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS 2019 1952 - 1955 2019.7

Authorship：Lead author,　Last author,　Corresponding author Language：English Publishing type：Research paper (international conference proceedings) Publisher：IEEE

In mathematical modeling of cell physiological processes, measurements required for parameter determination are often available only as aggregated data in the literature. Physiological measurements contain relatively large observation errors due to intrinsic variations in physiological processes, and the errors cause uncertainties in parameter values. This paper reports analyses of the uncertainty in parameter estimates of a simple mathematical model of an ion channel from a set of published experimental data. A conventional approach for estimating model parameters from aggregated data is applying the method of least squares to a series of the mean values of measurements. The parameter estimates by the conventional method significantly differed from those by a statistical approach, maximum likelihood estimation considering the standard errors of the means. Exhaustive analyses on the likelihood of parameter values show high parameter uncertainties and wide distribution of parameter values with no significant differences in the likelihood. These results imply the importance of considering variances of observations and uncertainties in parameter estimates.

DOI： 10.1109/EMBC.2019.8857142

Other Link： https://dblp.uni-trier.de/conf/embc/2019

個人情報保護と情報セキュリティを考慮したOffice 365 Educationの環境構築方法

嶋吉隆夫, 笠原義晃, 藤村直美

2019‐CSEC‐85 ( 5 ) 1 - 6 2019.5

嶋吉隆夫, 久志昇, 笠原義晃, 藤村直美

IEICE technical report 118 ( 480 ) 91 - 98 2019.3

Restructuring of Service Infrastructure for Office 365 in Kyushu University

嶋吉隆夫, 笠原義晃, 尾花昌浩, 藤村直美

大学ICT推進協議会年次大会論文集 ( 2018 ) 1 - 8 2018.11

Authorship：Lead author,　Corresponding author Language：Japanese Publishing type：Research paper (conference, symposium, etc.) Publisher：大学ICT推進協議会

九州大学では2016 年からOffice 365 を全学サービスとして正式に提供してきたが、その基盤システムやテナント運用などについて様々な課題が生じていた。そこで、基盤システムとテナントを含めて環境を新たに再構築し、2018 年4 月から新しいサービス環境の提供を開始した。本稿では、従来の環境における課題とその解決策、さらに、新しい環境の構築過程で生じた問題とその解決方法などについて紹介する。

A Preliminary Computational Model for Hypoxic Acidosis in Cardiac Myocytes Reviewed International journal

Takao Shimayoshi, Yuta Yamamoto, Tetsuya Matsuda

Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS 2018-July 4540 - 4543 2018.10

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (international conference proceedings) Publisher：IEEE

Intracellular acidosis induced by hypoxia resulted from myocardial ischemia damages myocardium. However, the detailed mechanisms of hypoxic acidosis are not quantitatively explained. The purpose of this study is to create a novel computational model which can reproduce intracellular acidosis caused by myocardial ischemia. We constructed a computational model of myocardium, by using a mathematical ventricular cell model which includes pH regulation and a computational model of myocardial microcirculation for calculating extracellular conditions. The present model reproduced cellular hypoxia in an ischemic condition simulated by a reduced blood flow, and intracellular pH reduction in response to the hypoxia.

DOI： 10.1109/EMBC.2018.8513112

PubMed

Other Link： https://dblp.uni-trier.de/conf/embc/2018

The past, current, and future of our email services in Kyushu University Reviewed

Yoshiaki Kasahara, Takao Shimayoshi, Eisuke Ito, Naomi Fujimura

Proceedings ACM SIGUCCS User Services Conference 103 - 106 2018.9

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

In Kyushu University, Information Infrastructure Initiative provides email service for students and staff members. Email services for students and staff members were started separately. For students, an email service was started as Unix accounts of "Computer System for Education" in 1995. On the other hand, an email service for staff members was started in 2009, and eventually the two mail services were merged into the current "Kyushu University Primary Mail Service" in 2014. The designs of these mail systems were affected by various operational issues and political decisions at their times. We think that running an in-house mail system is becoming less feasible due to the initial/operational cost, security issues, and our dwindling budget. For the current system, the planned 5-year lifetime ends in this fiscal year. Therefore, we are forced to migrate to a cloud-based mail service. In this presentation, we want to share our past experiences and future plans about our university email services.

DOI： 10.1145/3235715.3235737

Web of Science

精緻に制御可能な恒常性のある高集積マルチアカウント型のメール基盤

Other Link： https://dblp.uni-trier.de/db/conf/siguccs/siguccs2018.html#KasaharaSIF18

松本亮介, 小田知央, 笠原義晃, 嶋吉隆夫, 金子晃介, 栗林健太郎, 岡村耕二

情報処理学会シンポジウムシリーズ(CD-ROM) 2018 ( 1 ) 1383 - 1389 2018.6

Flexible Hosting/Cloud Platform Based on Light-Weight Containers and its Evaluation and Stress Test Environment

笠原義晃, 松本亮介, 近藤宇智朗, 小田知央, 嶋吉隆夫, 金子晃介, 岡村耕二

IEICE technical report 117 ( 471 ) 9 - 14 2018.3

Language：Japanese Publishing type：Research paper (conference, symposium, etc.) Publisher：電子情報通信学会

As basic components of ever-expanding internet services, hosting services and cloud computing platforms are expected to satisfy various requirements, such as efficiency, fault-tolerance, resiliency against high load, flexibility, and security. We are trying to solve these problems with a light-weight container based architecture (called FastContainer). To improve FastContainer (especially its auto-scaling function), we are creating an environment for performance and stress tests on a public cloud platform. In this paper, we describe the overview of FastContainer and details of the test environment, its current status, and future plans.

J-GLOBAL

A Design of Elaborately Analyzable Homeostatic E-mail System

松本亮介, 小田知央, 笠原義晃, 嶋吉隆夫, 金子晃介, 栗林健太郎, 岡村耕二

IEICE technical report 117 ( 471 ) 97 - 102 2018.3

Our experience with introducing microsoft office 365 in Kyushu University Reviewed

Yoshiaki Kasahara, Takao Shimayoshi, Masahiro Obana, Naomi Fujimura

Proceedings ACM SIGUCCS User Services Conference Part F131713 109 - 112 2017.10

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

Information Infrastructure Initiative of Kyushu University started serving Office 365 Education for all students and staff members at Kyushu University in November 2016. Since 2007, the university had signed Microsoft EES (Enrollment for Education Solutions) including licenses for the latest Microsoft Windows and Office suite. The EES agreement includes an advantage to provide Office 365 Education to the university members with minimum investments, and there was a demand for Skype for Business which is included in Office 365. To deploy Office 365 for our users, we first needed to configure our on-premises user authentication infrastructure to coordinate with Office 365. During trials, we had a couple of difficulties attributed to some disagreements between Microsoft's and our policy on whether the user identifier, namely the user principal name in Active Directory, was open or private. Additionally, we had to consider which services should be applied to the users, because we have been operating an on-premises email service which is competing with Microsoft Exchange mail service. In this presentation, we share our experiences in Office 365 deployment.

DOI： 10.1145/3123458.3123491

Web of Science