Faculty Profiles - YOSHIDA Keisuke

Papers - YOSHIDA Keisuke

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APPLICATION OF IMAGE GENERATION AI IN MODEL FOR DETECTING PLASTIC BOTTLES DURING RIVER PATROL USING UAV Reviewed

Daichi SHIMOE, Shijun PAN, Keisuke YOSHIDA, Satoshi NISHIYAMA, Takashi KOJIMA

Japanese Journal of JSCE 81 ( 16 ) n/a - n/a 2025.2

STUDY ON THE SURVEY OF RIVER SPACE UTILIZATION USING A RIVER MONITORING CAMERA, OBJECT DETECTION, AND A LARGE-SCALE MULTIMODAL MODEL Reviewed

Yuki YAMADA, Keisuke YOSHIDA, Shijun PAN, Takashi KOJIMA

Japanese Journal of JSCE 81 ( 16 ) n/a - n/a 2025.2

Interchangeability of Cross-Platform Orthophotographic and LiDAR Data in DeepLabV3+-Based Land Cover Classification Method Reviewed

Shijun Pan, Keisuke Yoshida, Satoshi Nishiyama, Takashi Kojima, Yutaro Hashimoto

Land 14 ( 2 ) 217 - 217 2025.1

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

Riverine environmental information includes important data to collect, and the data collection still requires personnel’s field surveys. These on-site tasks still face significant limitations (i.e., hard or danger to entry). In recent years, as one of the efficient approaches for data collection, air-vehicle-based Light Detection and Ranging technologies have already been applied in global environmental research, i.e., land cover classification (LCC) or environmental monitoring. For this study, the authors specifically focused on seven types of LCC (i.e., bamboo, tree, grass, bare ground, water, road, and clutter) that can be parameterized for flood simulation. A validated airborne LiDAR bathymetry system (ALB) and a UAV-borne green LiDAR System (GLS) were applied in this study for cross-platform analysis of LCC. Furthermore, LiDAR data were visualized using high-contrast color scales to improve the accuracy of land cover classification methods through image fusion techniques. If high-resolution aerial imagery is available, then it must be downscaled to match the resolution of low-resolution point clouds. Cross-platform data interchangeability was assessed by comparing the interchangeability, which measures the absolute difference in overall accuracy (OA) or macro-F1 by comparing the cross-platform interchangeability. It is noteworthy that relying solely on aerial photographs is inadequate for achieving precise labeling, particularly under limited sunlight conditions that can lead to misclassification. In such cases, LiDAR plays a crucial role in facilitating target recognition. All the approaches (i.e., low-resolution digital imagery, LiDAR-derived imagery and image fusion) present results of over 0.65 OA and of around 0.6 macro-F1. The authors found that the vegetation (bamboo, tree, grass) and road species have comparatively better performance compared with clutter and bare ground species. Given the stated conditions, differences in the species derived from different years (ALB from year 2017 and GLS from year 2020) are the main reason. Because the identification of clutter species includes all the items except for the relative species in this research, RGB-based features of the clutter species cannot be substituted easily because of the 3-year gap compared with other species. Derived from on-site reconstruction, the bare ground species also has a further color change between ALB and GLS that leads to decreased interchangeability. In the case of individual species, without considering seasons and platforms, image fusion can classify bamboo and trees with higher F1 scores compared to low-resolution digital imagery and LiDAR-derived imagery, which has especially proved the cross-platform interchangeability in the high vegetation types. In recent years, high-resolution photography (UAV), high-precision LiDAR measurement (ALB, GLS), and satellite imagery have been used. LiDAR measurement equipment is expensive, and measurement opportunities are limited. Based on this, it would be desirable if ALB and GLS could be continuously classified by Artificial Intelligence, and in this study, the authors investigated such data interchangeability. A unique and crucial aspect of this study is exploring the interchangeability of land cover classification models across different LiDAR platforms.

DOI： 10.3390/land14020217

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Trials of Night-Time 4K-Camera-based Human Action Recognition in Riverine Environments with Multimodal and Object Detection Technologies Reviewed

Shijun PAN, Keisuke YOSHIDA, Yuki YAMADA, Takashi KOJIMA

Intelligence, Informatics and Infrastructure 5 ( 1 ) 89 - 97 2024.11

Generating 3D Models for UAV-Based Detection of Riparian PET Plastic Bottle Waste: Integrating Local Social Media and InstantMesh Reviewed

Shijun PAN, Keisuke YOSHIDA, Daichi SHIMOE, Takashi KOJIMA, Satoshi NISHIYAMA

Drones 8 ( 9 ) 471 2024.9

Assessment of spawning habitat suitability for Amphidromous Ayu (Plecoglossus altivelis) in tidal Asahi River sections in Japan: Implications for conservation and restoration Reviewed

Keisuke Yoshida, Hiroshi Yajima, Md. Touhidul Islam, Shijun Pan

River Research and Applications 40 ( 8 ) 1497 - 1511 2024.6

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Wiley

Abstract

The Amphidromous Ayu (Plecoglossus altivelis), vital for Japan's riverine commercial fisheries, is experiencing population decline due to habitat degradation. In response, Japan is implementing restoration efforts by releasing juvenile fish and cultivating spawning habitats. This study, focusing on the Asahi River's Heidan area, evaluates Ayu spawning habitat suitability, especially in tidal zones, and its conservation implications. Through field surveys and numerical analysis, the research identifies optimal conditions for spawning amid dwindling numbers. Observations from the 2020 peak spawning season showed that water temperatures below 20°C are conducive to spawning, with the best sites producing up to 48,817 eggs/m². Gravel sizes between 0.85 and 53.0 mm were identified as crucial for effective spawning. Notably, artificial spawning grounds established in 2019 showed no spawning activity, likely due to saline intrusion from tides. Using the three‐dimensional hydrodynamic‐aquatic ecosystem numerical model, the study assesses flow, substrate, and water quality's impact on spawning, corroborated by sensor data. A key finding is the negative correlation between salinity and egg density in tidal sections of the Asahi River. Furthermore, an artificial intelligence (AI)‐based YOLOv5 model, trained on underwater images, effectively detected Ayu aggregations, demonstrating an F1‐score of 0.757 in differentiating Ayu from other coexisting fish species in the same aquatic environment. This AI approach provides a nonintrusive method for monitoring Ayu populations and habitat preferences. The research underlines that successful spawning habitats require minimal saline intrusion, with optimal salinity and flow conditions. These insights are critical for spawning ground development, emphasizing the management of tidal effects and riverbed conditions to bolster Ayu populations and preserve aquatic ecosystems.

DOI： 10.1002/rra.4329

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Monitoring Human Activities in Riverine Space using 4K Camera Images with YOLOv8 and LLaVA: A Case Study from Ichinoarate in the Asahi River Reviewed

Shijun PAN, Keisuke YOSHIDA, Yuki YAMADA, Takashi KOJIMA

Intelligence, Informatics and Infrastructure 5 89 - 97 2024.5

Comprehensive Analysis of On-Site Riparian Waste Pollution: A Case Study on the Hyakken River Basin Reviewed

Shijun PAN, Keisuke YOSHIDA, Takashi KOJIMA

Intelligence, Informatics and Infrastructure 5 98 - 103 2024.5

NUMERICAL REPRODUCTION OF OVERTHROW OF BAMBOO FOREST AND WASHOUT OF WOODY VEGETATION DURING FLOODING USING ESTIMATION OF THREE－DIMENSIONAL PROFILE OF VEGETATION DRAG FORCE WITH AERIAL LASER DATA AND FLOOD SIMULATION Reviewed

Ryo FURUTANI, Keisuke YOSHIDA, Takumi OKADA, Yuki KAJIKAWA, Satoshi NISHIYAMA

Japanese Journal of JSCE 80 ( 16 ) 23-16161 2024

CLASSIFICATION OF PHYTOPLANKTON GROUPS USING A MULTI-WAVELENGTH EXCIATION FLUOROMETER WITH RANDOM FOREST Reviewed

Hiroshi YAJIMA, Yo FUJII, Shogo SUGAHARA, Keisuke YOSHIDA

Japanese Journal of JSCE 80 ( 16 ) 23-16032 2024

DEEP LEARNING OF UNDERWATER IMAGES AND TRAINING DATA CRITERIA FOR UNDERSTANDING FEEDING INJURY OF ACANTHOPAGRUS SCHLEGELII IN NORI SEAWEED FARMS Reviewed

Keisuke YOSHIDA, Shijun PAN, Takahiro YOKOYAMA, Yasushi YAMASHITA, Yuki UEDA, Hiroyuki SUGINO, Takashi KOJIMA

Japanese Journal of JSCE 80 ( 16 ) 23-16150 2024

Mutual validation of remote hydraulic estimates and flow model simulations using UAV-borne LiDAR and deep learning-based imaging techniques Reviewed

Md Touhidul Islam, Keisuke Yoshida, Satoshi Nishiyama, Koichi Sakai

Results in Engineering 20 101415 - 101415 2023.12

Detection and Segmentation of Riparian Asphalt Paved Cracks Using Drone and Computer Vision Algorithms Reviewed

Shijun PAN, Keisuke YOSHIDA, Satoshi NISHIYAMA

Intelligence, Informatics and Infrastructure 4 ( 2 ) 35 - 49 2023.12

Application of the Prompt Engineering-assisted Generative AI for the Drone-based Riparian Waste Detection Reviewed

Shijun PAN, Keisuke YOSHIDA, Takashi KOJIMA

Intelligence, Informatics and Infrastructure 4 ( 2 ) 50 - 59 2023.12

Three-dimensional numerical modelling of floods in river corridor with complex vegetation quantified using airborne LiDAR imagery Reviewed

Keisuke Yoshida, Yuki Kajikawa, Satoshi Nishiyama, Md. Touhidul Islam, Shin Adachi, Koichi Sakai

Journal of Hydraulic Research 61 ( 1 ) 88 - 108 2023.1

Promises and uncertainties in remotely sensed riverine hydro‐environmental attributes: Field testing of novel approaches to unmanned aerial vehicle‐borne lidar and imaging velocimetry Reviewed

Md. Touhidul Islam, Keisuke Yoshida, Satoshi Nishiyama, Koichi Sakai, Shin Adachi, Shijun Pan

River Research and Applications 38 ( 10 ) 1757 - 1774 2022.12

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

Recent advancements in remotely sensed techniques have markedly expanded data acquisition potential in riverine studies, but the techniques' applicability must be validated and improved because of uncertainties associated with diverse field conditions. This study is the first experimental evidence of using a newly designed unmanned aerial vehicle (UAV)-borne green lidar system (GLS) and deep learning-automated space–time image velocimetry (STIV) for remote investigation of hydraulic and vegetation quantities of the gravel-bed Asahi River in Okayama Prefecture, Japan. In addition to identifying bed deformation in waters shallower than 2 m, the GLS point clouds characterized the submerged infrastructure with block detailing patterns, thereby identifying positional displacement and severely damaged parts. This paper also presents a noncontact method of estimating incremental river discharge. Compared to benchmarked flow model estimates, remotely sensed discharges for three transects covering shallower, deeper, and partially submerged woody vegetation areas were overestimated by 1–11%, with 4% underestimation for another cross-section. The STIV analysis also showed complicated flow patterns that were reasonably confirmed by flow vectors from depth-averaged modeling. Ultimately, depth-averaged flow model estimates validated hydraulic parameters derived remotely from GLS and STIV, and vice versa. In addition to approximating vegetation growth rates, the study using GLS attributes accurately identified riparian vegetation types as herbaceous (70%), woody (86%), and bamboo groves (65%). Finally, our findings provide insight into the management of shallow clear-flowing vegetated rivers and remote sensing of streamflow to validate hydrodynamic-numerical methods.

DOI： 10.1002/rra.4042

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Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/rra.4042

水中カメラの画像と深層学習による魚道を遡上する稚アユの検出に関する検討 Reviewed

潘是均, 古谷崚, 吉田圭介, 山下泰司, 小島崇, 白神義章

土木学会論文B1(水工学) 78 ( 2 ) I_127 - I_132 2022.11

The application of drone-assisted deep learning technology in riverbank garbage detection Reviewed

Shijun PAN, Keisuke YOSHIDA, Afia S. BONEY, Satoshi NISHIYAMA

Journal of JSCE, B1 78 ( 2 ) I_133 - I_138 2022.11

堤防越水場に設置した裏法面被覆工の不陸が流体力特性へ及ぼす影響に関する研究 Reviewed

飯干富広, 佐々木海音, 安達森, 忰熊公子, 吉田圭介

土木学会論文B1(水工学) 78 ( 2 ) I_655 - I_660 2022.11

PROJECT EVALUATION OF CROSS-SECTIONAL EXCAVATION WORK OF A SANDBAR IN THE ASAHI RIVER TIDAL ZONE FOR EXPANSION OF AYU SPAWNING BED AREA Reviewed

YOSHIDA Keisuke, ADACHI Maya, YAJIMA Hiroshi, YAMASHITA Yasushi, ADACHI Shin, FUJII Yo

Journal of Japan Society of Civil Engineers, Ser. B1 (Hydraulic Engineering) 78 ( 2 ) I_1111 - I_1116 2022.11

Authorship：Lead author,　Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Society of Civil Engineers

In order to increase the spawning bed area of Ayu in the Heidan area of the Asahi River tidal zone, a portion of a sandbar around a natural spawning ground was excavated and a new artificial spawning ground (sub-current channel) was constructed under normal flow conditions in a project. For this study, field observations and numerical calculations were conducted to examine the suitability of the hydraulic environment of the artificial spawning area creation. Additionally, we examined the impacts of the construction on the existing natural spawning habitat. Results showed that the suitable spawning area was an area where there was no salinity increase at any time, and that the river bed grain size, water depth during spawning time, and current velocity were within the suitable values proposed in previous works. Results also presented that the spawning density in the constructed area might be more dependent on the suitability of the grain size than on the flow regime. Furthermore, the results of high-resolution 2D horizontal calculations showed that the creation of the new spawning area did not significantly alter the hydraulic environment of the existing natural spawning grounds, and contributed to the increase in spawning bed area, which was the original purpose of the project.

DOI： 10.2208/jscejhe.78.2_i_1111

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旭川中原橋周辺の河道形状及び植生分布の違いが更正係数に与える影響に関する数値的検討 Reviewed

安達森, 梶川勇樹, 吉田圭介, 西山哲

土木学会論文B1(水工学) 78 ( 2 ) I_1153 - I_1158 2022.11

Drone-LiDAR-assisted Image Fusion methodology for Deep Learning-based Land Cover Classification Reviewed

Shijun PAN, Keisuke YOSHIDA, Takashi KOJIMA, Satoshi NISHIYAMA

Intelligence, Informatics and Infrastructure 3 ( 3 ) 15 - 25 2022.11

Authorship：Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Japan Society of Civil Engineers

This study uses an unmanned aircraft mounted green Light Detection and Ranging (LiDAR) system to verify the learnability associated with deep learning regarding land cover classification (i.e., evaluated by the average and the absolute difference value of label-based F1, overall accuracy or Macro F1 under the premise of cross-seasonal mutual-prediction). Image fusion method in this study mainly attempts to superimpose the visualized LiDAR data with the aerial photographs to provide new features. LiDAR data are visualized using high contrast color scale (default), average high contrast color scale (same color, different split points as default), and high contrast gray color scale (different color, same split points as default). The reason of setting these methods is to compare the impact of split points and point-associated color in the color scale on learnability of cross-seasonal data. It is worth noting, however from the view of the results, that relying solely on aerial photographs is not sufficient, comparing with image fusion method, especially when training and predicting using cross-seasonal data. From the comparison of the label-based F1, this study has proved the necessary impact of LiDAR on vegetation label-based land cover classification.

DOI： 10.11532/jsceiii.3.3_15

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YoloV5 analysis for juvenile ayu detection in underwater images of fishway Reviewed

Shijun Pan, Ryo Furutani, Keisuke Yoshida

Proc. of the 2022 Int. Symp. on Ecohydraulics 2022.10

Using airborne lidar bathymetry-aided transfer learning method in riverine land cover classification Reviewed

Shijun Pan, Keisuke Yoshida, Takashi Kojima

Proc. of the 2022 Int. Symp. on Ecohydraulics 2022.10

Developing 3-D numerical flood flow model for vegetated rivers: A case study for lower Asahi River flooding in Japan Reviewed

Md. Touhidul Islam, Keisuke Yoshida, Yuki Kajikawa, Satoshi Nishiyama

Proc. of 39th IAHR World Congress 2022.6

Novel UAV-borne green LiDAR versus traditional airborne LiDAR: A case study to characterize hydraulic and riparian vegetation attributes Reviewed

Md. Touhidul Islam, Keisuke Yoshida, Satoshi Nishiyama, Koichi Sakai

Proc. of 39th IAHR World Congress 2022.6

Airborne LiDAR-assisted deep learning methodology for riparian land cover classification using aerial photographs and its application for flood modelling Reviewed

Keisuke Yoshida, Shijun Pan, Junichi Taniguchi, Satoshi Nishiyama, Takashi Kojima, Md. Touhidul Islam

Journal of Hydroinformatics 24 ( 1 ) 179 - 201 2022.1

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：IWA Publishing

<title>Abstract</title>
In response to challenges in land cover classification (LCC), many researchers have experimented recently with classification methods based on artificial intelligence techniques. For LCC mapping of the vegetated Asahi River in Japan, the current study uses deep learning (DL)-based DeepLabV3+ module for image segmentation of aerial photographs. We modified the existing model by concatenating data on its resultant output port to access the airborne laser bathymetry (ALB) dataset, including voxel-based laser points and vegetation height (i.e. digital surface model data minus digital terrain model data). Findings revealed that the modified approach improved the accuracy of LCC greatly compared to our earlier unsupervised ALB-based method, with 25 and 35% improvement, respectively, in overall accuracy and the macro F1-score for November 2017 dataset (no–leaf condition). Finally, by estimating flow-resistance parameters in flood modelling using LCC mapping-derived data, we conclude that the upgraded DL methodology produces better fit between numerically analyzed and observed peak water levels.

DOI： 10.2166/hydro.2022.134

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Characterizing vegetated rivers using novel unmanned aerial vehicle‐borne topo‐bathymetric green lidar: Seasonal applications and challenges Reviewed

Md. Touhidul Islam, Keisuke Yoshida, Satoshi Nishiyama, Koichi Sakai, Tomoyuki Tsuda

River Research and Applications 38 ( 1 ) 44 - 58 2022.1

UAVレーザ点群と航空写真を併用した深層学習による河道の地被分類法の検討 Reviewed

野村碧都, 吉田圭介, 谷口純一

土木学会論文B1(水工学) 77 ( 2 ) I_913 - I_918 2021.12

旭川の感潮域におけるアユの好適な産卵場の検討 Reviewed

足立真綾, 吉田圭介, 矢島啓, 山下泰司

土木学会論文B1(水工学) 77 ( 2 ) I_1429 - I_1434 2021.12

Flood risk assessment in vegetated lower Asahi River of Okayama Prefecture in Japan using airborne topo-bathymetric LiDAR and depth-averaged flow model Reviewed

Keisuke Yoshida, Kimihisa nagata, Shiro maeno, Koji mano, Satoshi nishiyama, Md. Touhidul Islam

Journal of Hydro-environment Research 39 39 - 59 2021.10

Authorship：Lead author,　Corresponding author Language：English Publishing type：Research paper (scientific journal) Publisher：Elsevier BV

This paper describes application of airborne LiDAR bathymetry (ALB) with near-infrared and green pulsed lasers for gathering distributed vegetation conditions and topo-bathymetric data for rivers. For the lower Asahi River of Okayama Prefecture in Japan, the ALB data validity was verified using field observation data. This study also examined the applicability of ALB data for numerical simulations of the lower Asahi River flooding in early July 2018 in Japan, comparing simulated and observed data. Results demonstrated that the methodology for this study works well for parameterization of distributed vegetation on a reach scale. This study also applied numerical tests to investigate the effects of vegetation establishment on flood control plans for the lower Asahi River using parameters validated for flood flow simulations. Results demonstrate that the predicted water level markedly exceeds the high water level because of thick vegetation presently established along few-kilometerlong upstream sections of the targeted river reach. Therefore, we conclude that the present findings can support cost-effective management tasks for vegetated rivers.

DOI： 10.1016/j.jher.2021.06.005

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平成30 年7月豪雨時の旭川分流堰周辺の植生分布を考慮した3次元洪水流解析 Reviewed

吉田圭介,梶川勇樹,永田貴美久,西山哲,間野耕司,堺浩一,Md. Touhidul ISLAM,児子真也

土木学会論文集B1(水工学) 76 ( 2 ) I_985 - I_990 2020.12

Model-induced comparative study of ALB and UAV-borne green LiDAR systems on vegetated lower Asahi river assessment in Japan Reviewed

Md. Touhidul ISLAM, Keisuke YOSHIDA, Koichi SAKAI, Satoshi NISHIYAMA, Tomoyuki TSUDA, Kimishisa NAGATA and Shiro MAENO

土木学会論文集B1(水工学) 76 ( 2 ) I_529 - I_534 2020.12

ALB-ASSISTED DEEP LEARNING OF AERIAL PHOTOGRAPHS FOR LAND-COVER CLASSIFICATION IN RIVERS Reviewed

YOSHIDA Keisuke, TANIGUCHI Junichi, PAN Shijun, KOJIMA Takashi, NAGATA Kimihisa, WATANABE Akihide

Journal of Japan Society of Civil Engineers, Ser. B1 (Hydraulic Engineering) 76 ( 2 ) I_1003 - I_1008 2020.12

Authorship：Lead author,　Corresponding author Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Society of Civil Engineers

Land cover classification (LCC) map in rivers is one of the important fundamental materials for hydraulic research works and practical tasks in terms of both flood control and water environment conservation. Recently, massive flooding because of heavy rainfall motivates hydraulic engineers to estimate the flow capacity at local river sections accurately by re-evaluating the LCC map of the cross-sectional area, vegetation height, and vegetation density, using useful remote sensing methods such as airborne laser bathymetry (ALB). For this work, we developed a new methodology for land cover classification (water area, bare ground, herbaceous species, arborous species, and bamboo grove) in rivers. We used an image processing technique of deep convolutional neural networks (DCNNs) for aerial photographs taken during ALB measurements in conjunction with the dataset of laser point cloud and vegetation height (digital surface model data minus digital terrain model data). We applied our method to two flights of ALB measurement data (in March 2017 and November 2017) for the 4.5 km-long lower reach of the Asahi River. Results showed that our method predicts the LCC map more accurately in case of support of the ALB dataset, especially for detection of herbaceous species, compared with predictions using aerial photographs only. However, if we use different season dataset for learning and prediction processes, classification performance is degraded largely for arborous species because of defoliation.

DOI： 10.2208/jscejhe.76.2_i_1003

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Verification of STIV analysis of flood discharge at Nakano observatory in the Ota River by flow analysis using ALB data Reviewed

K. Yoshida, S. Nigo, S. Maeno, K. Mano, M. Nakano

Proc. 22nd IAHR-APD Congress 2020.9

Flood simulation model coupled with woody vegetation wash-out in the lower Asahi River Reviewed

K. Nagata, K. Yoshida, S. Maeno, S. Nigo, MD. T. Islam

Proc. 22nd IAHR-APD Congress 2020.9

Estimation of distributed flow resistance in vegetated rivers using airborne topo-bathymetric LiDAR and its application to risk management tasks for Asahi River flooding Reviewed

Keisuke Yoshida, Shiro Maeno, Shuhei Ogawa, Koji Mano and Shinya Nigo

Journal of Flood Risk Management 13 ( 1 ) e12584 2020.3

植生高分布と限界掃流力を考慮した植生流出を伴う洪水流解析モデルの検討 Reviewed

吉田圭介,前野詩朗,永田貴美久,児子真也,赤穗良輔

土木学会論文集B1(水工学) 75 ( 4 ) I_325 - I_330 2019.12

2018 年7 月西日本豪雨時の岡山県での降雨特性と旭川水系での洪水被害の調査解析 Reviewed

吉田圭介,前野詩朗,工藤亮治,近森秀高,赤穗良輔,小川修平,永田貴美久

土木学会論文集B1(水工学) 75 ( 1 ) 172 - 183 2019.12

FLOOD DISASTER CHARACTERISTICS IN MABI DISTRICT OF KURASHIKI CITY DUE TO HEAVY RAIN IN 2018 AND INVESTIGATION OF FLOODING SCENARIO USING RIVER FLOOD FLOW COMBINED INUNDATION FLOW MODEL Reviewed

MAENO Shiro, AKOH Ryosuke, NIHEI Yasuo, AKAMATSU Yoshihisa, YOSHIDA Keisuke

Journal of Japan Society of Civil Engineers, Ser. B1 (Hydraulic Engineering) 75 ( 1 ) 387 - 402 2019.12

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Society of Civil Engineers

<p> Due to the heavy rain of July in 2018, several levees of the Oda River flowing through the Mabi district of Kurashiki City and its tributaries, the Suemasa River, the Takama River, and the Madani River, were breached. Inundation area reached 1,200 ha in Mabi district and maximum inundation depth was more than 5 m, and eventually 51 people died there. First, in this study, the inundation state was clarified by the field survey. And flooding scenario was examined using an integrated flooding simulation model that analyzes the flood flow of rivers and the inundation flow from the breaching points. At first, the analysis was performed without breaching condition of levee to estimate the time to start overflowing the levee. Then simulations under breaching condition was carried out to clarify the inundation process. Numerical results of inundation depth show in good agreement with the field surveyed results.</p>

DOI： 10.2208/jscejhe.75.1_387

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太田川中野観測所におけるSTIV流量観測とALBデータを用いた水理解析による精度検証 Reviewed

児子真也,吉田圭介,前野詩朗,間野耕司,中野光隆

土木学会論文集B1(水工学) 75 ( 4 ) I_613 - I_618 2019.12

数値浮子モデルとDIEX法をカップリングさせた洪水流量推定法の構築と現地適用 Reviewed

赤穗良輔,前野詩朗,中山彰人,吉田圭介

土木学会論文集B1(水工学) 75 ( 4 ) I_625 - I_630 2019.12

環境DNA 分析と物理環境調査による旭川下流部におけるアユの産卵可能性の検討 Reviewed

吉田圭介,乾隆帝,宇田川涼平,前野詩朗,赤松良久,児子真也,?橋幸生,永田貴美久

土木学会論文集B1(水工学) 75 ( 4 ) I_529 - I_534 2019.12

Evaluation of discharge equation of lateral overflow located in the curved part of river, Reviewed

M. Ishihara, R. Akoh, S. Maeno and K. Yoshida

Proc. of 38th IAHR World Congress 2019.9

ALBによる河道地形の再現性向上に伴う河床変動解析の改善効果の検討 Reviewed

山口華穂,吉田圭介,前野詩朗,間野耕司,赤穗良輔,西山哲

土木学会論文集A2（応用力学） 74 ( 2 ) I_465 - I_474 2019.2

水路湾曲部に設置される横越流堤の流量公式の検討 Reviewed

石原正義,赤穂良輔,前野詩朗,吉田圭介

土木学会論文集B1(水工学) 74 ( 5 ) I_841 - I_846 2018.12

ALB計測データを用いた流況解析に基づく旭川下流部におけるアユの産卵場の物理環境評価 Reviewed

吉田圭介,前野詩朗,高橋幸生,児子真也,小川修平,赤穗良輔

土木学会論文集B1(水工学) 74 ( 5 ) I_421 - I_426 2018.12

Estimation of hydrodynamic forces acting on concrete blocks of toe protection works for coastal dikes by tsunami overflows Reviewed

Keisuke Yoshida, Shiro Maeno, Tomihiro Iiboshi, Daisuke Araki

Applied Ocean Research 80 181 - 196 2018.11

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

The extraordinary tsunami generated by the Great East Japan Earthquake in 2011 destroyed coastal protection facilities in the Tohoku region. After the catastrophe, landward toe protection works comprising concrete blocks were proposed at damaged coastal areas. However, the hydrodynamic behavior of the protection works against tsunami overflows has not been fully elucidated by earlier experimental studies. Therefore, this study investigated validity of three-dimensional (3-D) numerical simulations of tsunami flows over a simulated coastal dike with protection works of concrete block models. This study also presented a method of estimating the hydrodynamic forces acting on block models under the tsunami overflows. After conducting basic validation of the present numerical method, we compared experimentally obtained results of hydrodynamic forces to results obtained from simulations. Results show that the simulation data are qualitatively consistent with experimental data for the considered cases of overflow depths of four kinds. They also presented that the characteristics of hydrodynamic forces depend mainly on both the distance from the dike foundation and tsunami overflow depth. The salient finding is that the hydrodynamic forces are affected to a considerable degree by the irregularity of the block model arrangement or surface asperity of the protection works. The impulsive force of tsunami overflows at actual coasts will perturb concrete blocks placed in orderly rows at the original installation. Therefore, the landward toe protection works using concrete blocks necessitate supportive constructions to enhance their structural stability.

DOI： 10.1016/j.apor.2018.09.001

Scopus

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12th Int. Symp. on Ecohydraulics 2018.8

Remote sensing of morphodynamics and habitats in rivers using airborne LiDAR bathymetry Reviewed

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Proc. 20th IAHR-APD Congress 2016.8

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K.Yoshida, S. Ushijima, R. Tanaka, N. Miyagi, S. Maeno

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土木学会論文集A1（応用力学） 70 ( 2 ) I_701 - I_708 2015.2

Effects of landward slope protection and toe protection work shape at coastal dikes on landward bed scouring caused by tsunami overflow Reviewed

Tomihiro Iiboshi, Shiro Maeno, Keisuke Yoshida, Daisuke Takata, Akira Yamamura

Proc. of the 36th IAHR World Congress 4103 - 4111 2015

Language：English Publishing type：Research paper (international conference proceedings) Publisher：IAHR-INT ASSOC HYDRO-ENVIRONMENT ENGINEERING RESEARCH

Coastal dikes in Iwate, Miyagi, and Fukushima prefectures in Japan were damaged severely by tsunami overflow consequent to the 2011 off-the-Pacific coast of Tohoku Earthquake. A main factor of the failure was landward bed scouring following the tsunami overflow. Coastal dikes were destroyed completely or partially because of embankment material outflows caused by scouring of the landward bed. Because of this severe damage, the tsunami committee in Japan recommended several methods to produce resilient structures for coastal dikes. One method is landward toe protection works to reduce the landward toe bed scouring. It can improve the coastal dike stability. However, the relation of protection work shapes to landward bed scouring characteristics remains unclear. Therefore, we particularly examined the effects of landward slope and toe protection work shapes on landward bed scouring. We conducted small-scale experiments to clarify the effects of works with different characteristics. The obtained results demonstrate that a large scouring hole was formed around the landward toe area in any shape of the slope protection works without bed protection works. Landward bed protection works can reduce size of the scouring hole. A surface protuberances of landward toe protection works is more effective to reduce the scouring depths and areas.

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津波越流による海岸堤防裏法尻の洗掘に及ぼす裏法被覆工と法尻保護工形状の影響 Reviewed

飯干富広,前野詩朗,吉田圭介,高田大資

土木学会論文集B2（海岸工学） 70 ( 2 ) I_966 - I_970 2014.11

Inverse estimation of distributed roughness coefficients in vegetated flooded rivers Reviewed

Keisuke Yoshida, Shiro Maeno

Journal of Hydraulic Research 52 ( 6 ) 811 - 823 2014.9

Study on characteristics of hydrodynamic force on slope and landward toe protection works of coastal dikes due to tsunami overflow Reviewed

T. Iiboshi, S. Maeno, K. Yoshida, D. Takata

19th IAHR-APD Congress 2014.9

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Numerical simulation of tsunami inundation in Okayama city, Japan Reviewed

K. Kudai, K. Yoshida, S. Maeno

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K. Yoshida, S. Maeno, S. Fujita, S. Matsuyama

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STUDY ON CHARACTERISTICS OF PRESSURE AND HYDRODYNAMIC FORCES ON COASTAL DIKE DUE TO TUNAMI OVERFLOW Reviewed

IIBOSHI Tomihiro, MAENO Shiro, YOSHIDA Keisuke, TAKATA Daisuke

Journal of Japan Society of Civil Engineers, Ser. B3 (Ocean Engineering) 70 ( 2 ) I_498 - I_503 2014.8

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Society of Civil Engineers

 Coastal dikes in Iwate, Miyagi, and Fukushima prefectures were seriously damaged due to the tsunami overflow by the 2011 off the Pacific coast of Tohoku Earthquake. However, hydrodynamic forces acting on the landward toe protection works were not clarified at present state. Therefore, hydrodynamic pressure of the dike slope and hydrodynamic force of the landward toe protection works due to tsunami overflow were experimentally investigated using different types of coastal blocks. The obtained results show that uplift force of the landward toe armoring block does not proportionally increase with the increase of tsunami height. Although surface protuberances of blocks of landward toe bed protection works increase the hydrodynamic force, they have the effect to reduce the velocity related to scouring. On the other hand, stepwise armoring blocks have the effect to decrease hydrodynamic force and reduce the velocity over the landward toe protection blocks.

DOI： 10.2208/jscejoe.70.I_498

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土木学会論文集B1(水工学) 69 ( 4 ) I_721 - I_726 2013.3

旭川の大原箇所における植生生長と洪水時の植生流出条件の検討 Reviewed

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土木学会論文集B1(水工学) 69 ( 4 ) I_727 - I_732 2013.3

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Keisuke Y. and Tadaharu I.

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Z. Wang, T. Ishikawa and K. Yoshida

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Flood flow analysis using a quasi-three-dimensional flow model and aerial photos Reviewed

Keisuke Y., Tadaharu I. and Yasuhisa M.

Proc. 3rd Int. Symp. on Shallow Flows, 2012.6

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吉田圭介, 石川忠晴

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土木学会論文集B1（水工学） 68 ( 1 ) 67 - 76 2012

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土木学会論文集B1（水工学） 67 ( 3 ) 155 - 167 2011.11

浅水流adjointモデルによる河床粗度の時間変化の逆推定法に関する基礎的検討 Reviewed

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応用力学論文集 14 ( 2 ) I_533 - I_540 2011.9

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Yoshida, K. and Ishikawa, T.

Proc. 34th IAHR Congress 4392 - 4399 2011.6

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水工学論文集 55 S_1009 - S_1014 2011.3

Inverse estimation of bed roughness coefficients of open-channel by using adjoint model in shallow-water flows Reviewed

YOSHIDA Keisuke

Journal of Hydroscience and Hydraulic Engineering 29 ( 1 ) 1 - 13 2011

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Yoshida, K. and Ishikawa, T.

Proc. 17th APD-IAHR Congress 3a043 2010.2

変分法と浅水流モデルを併用した河床粗度の逆推定法に関する研究 Reviewed

吉田圭介, 石川忠晴

水工学論文集 54 991 - 996 2010

Derivation of upstream boundary condition for 3-D numerical simulation of sediment dispersion around the Yangtze River mouth, China Reviewed

Wang, Z., Yoshida, K and Ishikawa, T.

Proc. 3rd Int. Conf. on Estuaries & Coasts 754 - 761 2009.9

実体視と画像相関解析を併用した洪水航空写真解析手法の構築と検証 Reviewed

箕浦靖久, 石川忠晴, 吉田圭介

水工学論文集 53 997 - 1002 2009

準3次元CIP-Sorobanモデルによる利根川洪水流の大規模数値計算 Reviewed

吉田圭介, 石川忠晴, 箕浦靖久

水工学論文集 53 877 - 882 2009

Quasi-3D solver of meandering river flows by CIP-Soroban scheme in cylindrical coordinates with support of boundary fitted coordinate method Reviewed

Yoshida, K. and Ishikawa, T.

Proc. 16th APD-IAHR Congress 2008.9

Flood flow analysis on aerial photos by image correlation method with support of stereo visualization Reviewed

Minoura, Y., Ishikawa, T. and Yoshida, K.

Proc. 16th APD-IAHR Congress 999 - 1004 2008.9

Flow solver of arbitrarily meandering river by CIP-Soroban-BFC scheme with quasi-3D method Reviewed

Yoshida, K. and Ishikawa, T.

Proc. 8th International Conference on HydroScience and Engineering 2008.9

Derivation of boundary condition for quasi-3D model of water exchange between Neijiang and Yangtze river Reviewed

Zhao, L., Yoshida, K., Ishikawa, T. and Futagi, K.

Proc. 16th APD-IAHR Congress 491 - 496 2008.9

Study on turbidity increase during flood in Myoginohana area of lake Kasumigaura Reviewed

Yoshida, K., Ishikawa, T., Kobayashi, Y., Sasaki, F., Aoyama, S. and Ichiyama, M.

Proc. 16th APD-IAHR Congress 472 - 477 2008.9

円筒座標CIP-Soroban法と境界適合座標法を組み合わせた蛇行河川の準3次元計算法 Reviewed

吉田圭介, 石川忠晴

水工学論文集 52 997 - 1002 2008

Depth-averaged numerical solver of meandering river flows by CIP-Soroban grids in cylindrical coordinate system Reviewed

Yoshida,K, Ishikawa, T

Journal of Hydroscience and Hydraulic Engineering, JSCE 26 ( 1 ) 11 - 28 2008

鎮江市内江の流動計算のための長江水理条件の導出 Reviewed

趙聯芳, 吉田圭介, 石川忠晴, 二木敬右

水工学論文集 52 1051 - 1056 2008

Numerical prediction of meandering river flows by CIP-Soroban grids in cylindrical coordinate system Reviewed

Yoshida, K. and Ishikawa, T.

Proc. 32nd IAHR Congress 2007.7

霞ヶ浦の妙技の鼻水域における出水時濁度上昇に関する研究 Reviewed

吉田圭介, 石川忠晴, 佐々木史, 青山貞雄, 市山誠

河川技術論文集 Vol.13 13 - 18 2007

EFFICIENT ANALYSIS OF RIVER FLOW FIELD ON AERIAL PHOTOGRAGHS BY CORRELATION METHOD WITH SUPPORTE OF STEREO VISUALIZATION Reviewed

MINOURA Yasuhisa, ISHIKAWA Tadaharu, YOSHIDA Keisuke

Doboku Gakkai Ronbunshuu B Vol.51 1093 - 1098 2007

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Society of Civil Engineers

Stereo images obtained from sequential aerial photographs of river freshets contain a lot of useful information for river hydraulics as well as river engineering works. The image correlation analysis is a standard technique for analyzing the images, but it sometimes produces anomalous results for the area where color fluctuation of the water surface is small. On the other hand, a classical manual analysis through stereo eyeglasses usually works well even in such unclear parts of the images, but the manual analysis costs much labor and time. <BR>In this study, a new technique to analyze stereo images of river flows is developed by combining the above mentioned two methods: A small amount of suggestions are made by using the results from the manual analysis for the image correlation analysis on a computer, and then the results of the second trial of the latter is much improved without any significant time consumption.

DOI： 10.2208/prohe.51.1093

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NUMERICAL SOLVER FOR SHALLOW-WATER MODEL OF MEANDERING RIVER FLOWS BY CIP-SOROBAN SCHEME IN CYLINDRICAL COODINATE SYSTEM Reviewed

YOSHIDA Keisuke, ISHIKAWA Tadaharu

Doboku Gakkai Ronbunshuu B Vol.51 805 - 810 2007

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Society of Civil Engineers

A new numerical solver is developed for a shallow-water flow model to simulate meandering river flows. This solver can investigate the flows in the curved river channel, by means of the adaptive CIP-Soroban (CIP-S) scheme in a cylindrical coordinate system. Time development of water velocity and free-surface level is computed by the orthogonal curvilinear coordinate system without any transformation of the governing equations, and the advection term is calculated by the high-accuracy CIP scheme. The numerical grid points of the waterfront line at the river bank are moved and tracked by the kinematic condition so that the grid points are always located on the line, and the rearrangement of the positions of the girds is easily conducted by the original CIP-S method. From the verification of this solver by the pure advection problem and by the numerical solution of the meandering river flows, in comparison with the CIP-S method in a Cartesian coordinate system and with the boundary fitted coordinate (BFC) method, it is shown that the proposed numerical solver reasonably predicts the main flow profile and water surface elevation and will be a promising numerical method as one of the practical solutions.

DOI： 10.2208/prohe.51.805

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Fundamental investigation of depth-averaged numerical model with evolution of secondary currents in curved channels Reviewed

Yoshida, K. and Ishikawa, T.

Proc. 15th APD-IAHR Congress 2006.8

2次流の時空間発展を考慮した水深積分モデルに関する基礎的検討 Reviewed

吉田圭介, 石川忠晴

水工学論文集, 第50巻 pp.781-786 781 - 786 2006

Direct numerical simulation of two-fluid system and its application to air-water turbulent flows with deformed interfaces Reviewed

Yoshida, K., Ushijima, S. and Nezu, I.

Proc. 31st IAHR Congress 836 - 846 2005.9

風シアーと底面シアーが共存する開水路混成流における組織乱流構造と気液界面気体輸送過程に関する研究 Reviewed

吉田圭介,禰津家久

土木学会論文集 803/II-73 57 - 67 2005.5

DIRECT NUMERICAL SIMULATION OF AIR-WATER TURBULENT FLOWS WITH DEFORMED INTERFACE Reviewed

YOSHIDA Keisuke, USHIJIMA Satoru, NEZU Iehisa

Doboku Gakkai Ronbunshuu B 49 709 - 714 2005

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Society of Civil Engineers

In this study, a direct numerical simulation for analyzing the immiscible incompressible two-fluid flows was carried out with the 3-dimensional MARS method, and the applicability of this scheme was verified in the water column collapse phenomenon, 2-dimesional channel flows between two walls and 3-dimensinal air-water co-current flows between a non-slip wall and a free-slip wall. It was shown that the present numerical simulation was in good agreement with previous experimental and numerical results, and that the volume of fluid in flows was sufficiently conserved for the long simulation time step. However, it is pointed out in the 3-D air-water co-current flows that lack of simulation grids and inadequate averaged time generates the inaccurate results in this DNS.

DOI： 10.2208/prohe.49.709

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逆流風波開水路混成場における乱れ構造と気体輸送に関する実験的研究 Reviewed

禰津家久, 福谷彰, 吉田圭介, 垂井晃一

応用力学論文集 8 911 - 918 2005

TURBULENCE CHARACTERISTICS IN ADVERSE WIND-DRIVEN OPEN-CHANNEL FLOWS Reviewed

NEZU Iehisa, TARUI Kouichi, YOSHIDA Keisuke

Doboku Gakkai Ronbunshuu B 49 505 - 510 2005

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Society of Civil Engineers

This study describes an experimental investigation on turbulence characteristics and the water-surface fluctuations in adverse wind-driven open-channel flows by using both a laser Doppler Anemometer (LDA) and a wave gauge simultaneously. In this study, it was shown that the velocity fluctuations of water flow near the interface in not only cocurrent flow but also adverse flow are significantly affected by the water surface in every range of frequency. However turbulence characteristics in water layer in adverse wind-driven open-channel flows are different from those in cocurrent flow, and there exists a high correlation between turbulence and the surface fluctuations in predominant frequency due to high-sheared wind flow.

DOI： 10.2208/prohe.49.505

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Experimental study on air-water interfacial turbulent hydrodynamics and gas transfer in wind-induced open-channel flows Reviewed

Yoshida, K. and Nezu, I.

Proc.4th International Symposium on Environmental Hydraulics 185 - 191 2004.12

Numerical prediction of incompressible two-fluid system and its application to stratified flows with water and silicone-oil, Reviewed

K. Yoshida, S. Ushijima and I. Nezu

Proc. 14th APD-IHAR 309 - 309 2004.12

水面上に風シアーが存在する開水路流場における水層乱れ構造と水面変動に関する研究 Reviewed

禰津家久, 吉田圭介, 垂井晃一

水工学論文集 Vol.48 517 - 522 2004

風シアーを伴う開水路乱流場における水層組織渦構造に関する研究 Reviewed

吉田圭介, 禰津家久, 垂井晃一

応用力学論文集 Vol.7 1051 - 1060 2004

Fundamental study on air-water interfacial coherent structures in wind-induced water-waves flows by PIV measurements Reviewed

Nezu, I. and Yoshida, K.

Proc. 30th IAHR Congress C-1 235 - 242 2003.8

Computation of immiscible two-fluid flows with a unified numerical procedure Reviewed

Yoshida, K., Ushijima, S. and Nezu, I.

Proc. 30th IAHR Congress D 663 - 670 2003.8

FUNDAMENTAL STUDY ON AIR-WATER INTERFACIAL COHERENT STRUCTURES IN WIND-INDUCED WATER WAVES FLOWS BY PIV MEASUREMENTS Reviewed

NEZU Iehisa, YOSHIDA Keisuke, IKEDA Daisuke

Doboku Gakkai Ronbunshuu B Vol.47 457 - 462 2003

Language：Japanese Publishing type：Research paper (scientific journal) Publisher：Japan Society of Civil Engineers

This paper describes an experimental study on turbulent bursting phenomena across air-water interface in wind-induced water waves by using Particle-Image Velocimetry (pry). The purpose of this study is to clarify coherent structures near the air-water interface in a wind-driven shear layer, and to evaluate an effect on momentum transport due to the busting events from the interfacial water to water-body flow. As the results of experiments, it is shown that the water flow is a combined flow with a wall shear flow and orbital motions, and that the wave-induced fluctuations have major power in the whole velocity fluctuations. In particular, when the bursting events are detected near the air-water interface by human eyes in the time-series of PIV raw images, only the low-frequency fluctuations are enhanced obviously at that time in wavelet-filter analysis. Therefore, it is inferred that the mechanism of water momentum transport is organized by the wave-induced fluctuations from the air-water interface to the water bulk, not by the bursting events with small fluctuations. It is also recognized by PIV measurements that the busting events are closely related to the unsteady wave-induced velocity fluctuations near the interface.

DOI： 10.2208/prohe.47.457

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風波発生下における自由水面近傍での組織構造に関する基礎的研究 Reviewed

禰津家久, 吉田圭介, 池田大輔, 垂井晃一

応用力学論文集 Vol.6 933 - 942 2003

A FUNDAMENTAL STUDY ON AIR-WATER TURBULENT STRUCTURES IN WIND-INDUCED OPEN-CHANNEL FLOWS Reviewed

NEZU Iehisa, YOSHIDA Keisuke, USHIJIMA Satoru

733/II-63 ( 733 ) 67 - 76 2003

FIFTH-ORDER CONSERVATIVE SCHEME WITH FLUX CONTROL APPLICABLE TO CONVECTION EQUATIONS Reviewed

USHIJIMA Satoru, YOSHIDA Keisuke, TAKEMURA Masaki, NEZU Iehisa

747/II-65 ( 747 ) 85 - 94 2003

非圧縮性混相流場に対する数値解法と水-シリコンオイル成層流への適用性に関する考察 Reviewed

牛島省, 吉田圭介, 禰津家久

応用力学論文集 6 891 - 898 2003

Experimental Study on Mutual Turbulent Structures across Air-Water Interface in Wind-Induced Water Waves by Synchronous LDA Measurements Reviewed

Nezu,I, Yoshida,K, Ikeda,D

Journal of Hydroscience and Hydraulic Engineering, JSCE. Vol.21 ( No.1 ) 63 - 70 2003

自由水面流れの数値計算における内部流動の解析精度に関する考察 Reviewed

牛島省, 禰津家久, 吉田圭介, 池田大輔

水工学論文集 Vol.47 409 - 414 2003

Numerical prediction of free surface flows with QSI scheme on collocated grid system Reviewed

Ushijima, S., Yoshida, K., Takemura, M. and Nezu, I.

Proc. 10th international symposium on flow visualization F0162 2002.8

Numerical prediction of free surface flows with QSI scheme on collocated grid system Reviewed

S. Ushijima, I. Nezu and K. Yoshida

Proc. 13th APD-IAHR Symp. 322 - 326 2002.8

Turbulence visualization of multi-scale water velocity fluctuations of wind-driven water waves in air-water two-phase flows Reviewed

I. Nezu, K. Yoshida and S. Ushijima

Proc. 10th International symposium on flow visualization F0088 2002.8

Experimental study on interfacial turbulent structures in wind-induced water waves by synchronous LDA measurements Reviewed

I. Nezu, S. Ushijima and K. Yoshida

Proc. 13th APD-IAHR Symp. 38 - 43 2002.8

水・空気層の同時計測による風波界面近傍流体の相関構造に関する研究 Reviewed

禰津家久, 吉田圭介

水工学論文集 Vol.46 547 - 552 2002

Study on turbulent structures of air-induced water waves by using phase-averaged PIV measurements Reviewed

Nezu, I., Ushijima, S., Onitsuka, K. and Yoshida, K

Proc. 3rd Int. Symp. on Measurement Techniques for Multiphase Flows 211 - 220 2001.8

PIV measurements of turbulent structures across air-water interface in wind-driven water waves Reviewed

Nezu, I., Ushijima, S., Onitsuka, K. and Yoshida, K.

Pcoc. 6th Asian Symp. on Visualization 363 - 365 2001.5

TURBULENT STRUCTURE AT THE AIR-WATER INTERFACE IN AIR-INDUCED WIND WATER WAVE ASSOCIATED WITH BREAKING WAVES Reviewed

NEZU Iehisa, USHIJIMA Satoru, YOSHIDA Keisuke

684/II-56 ( 684 ) 69 - 80 2001

PIV法を用いた砕波を伴う風波の界面乱流構造に関する研究 Reviewed

禰津家久, 井上理恵, 吉田圭介

応用力学論文集,Vol.3 3 775 - 786 2000

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