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

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

DOI： 10.2208/jscejj.24-16180

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

DOI： 10.2208/jscejj.24-16190

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

DOI： 10.11532/jsceiiai.5.1_89

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DOI： 10.3390/drones8090471

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

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

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

DOI： 10.2208/jscejj.23-16161

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

DOI： 10.2208/jscejj.23-16032

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

DOI： 10.2208/jscejj.23-16150

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.rineng.2023.101415

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

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

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

DOI： 10.1080/00221686.2022.2106596

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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

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

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

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

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

DOI： 10.2208/jscejhe.78.2_i_133

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

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

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

DOI： 10.1002/rra.3875

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Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/rra.3875

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

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

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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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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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DOI： 10.1111/JFR3.12584

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DOI： 10.2208/jscejhe.75.1_172

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

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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

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DOI： 10.1016/j.jher.2014.12.003

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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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DOI： 10.1080/00221686.2014.932854

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

&nbsp;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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DOI： 10.2208/prohe.52.997

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DOI： 10.2208/prohe.52.1051

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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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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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DOI： 10.2208/prohe.50.781

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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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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：土木学会  

DOI： 10.2208/journalam.8.911

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

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

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

DOI： 10.2208/prohe.48.517

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

DOI： 10.2208/journalam.7.1051

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

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

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

DOI： 10.2208/journalam.6.933

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

DOI： 10.2208/jscej.2003.733_67

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CiNii Books

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

DOI： 10.2208/jscej.2003.747_85

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CiNii Books

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：土木学会  

DOI： 10.2208/journalam.6.891

CiNii Article

CiNii Books

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

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

DOI： 10.2208/prohe.46.409

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

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

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

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

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

DOI： 10.2208/prohe.46.547

CiNii Article

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

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

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

DOI： 10.2208/jscej.2001.684_69

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CiNii Books

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

DOI： 10.2208/journalam.3.775

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Event date： 2019.6

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2019.6

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2018.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2018.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2018.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2018.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2018.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2018.5

Language：Japanese   Presentation type：Poster presentation  

Venue：名城大学  

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Event date： 2017.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2017.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：京都大学  

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Event date： 2017.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2017.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2017.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2017.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2017.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2017.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2016.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2016.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2016.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2016.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2016.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2016.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2016.5

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：北海道大学  

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Event date： 2016.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2015.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2015.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2015.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2015.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2015.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2014.5.10

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2014.5.10

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2014.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2014.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2014.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2014.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2014.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2013.6

Presentation type：Oral presentation (general)  

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Event date： 2013.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2013.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2013.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2013.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2013.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2012.9

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2009.12

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2006.9

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2004.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2003.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2003.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2002.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2002.5

Presentation type：Oral presentation (general)  

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Event date： 2001.12

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2001.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Event date： 2000.5

Language：Japanese   Presentation type：Oral presentation (general)  

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Language：Japanese   Presentation type：Oral presentation (general)  

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Language：Japanese   Presentation type：Oral presentation (general)  

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Language：Japanese   Presentation type：Oral presentation (general)  

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Language：English   Presentation type：Oral presentation (general)  

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Language：Japanese   Presentation type：Oral presentation (general)  

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Language：Japanese   Presentation type：Oral presentation (general)  

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Language：English   Presentation type：Oral presentation (general)  

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Language：English   Presentation type：Oral presentation (general)  

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Language：English   Presentation type：Oral presentation (general)  

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Language：Japanese   Presentation type：Oral presentation (general)  

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Language：Japanese   Presentation type：Oral presentation (general)  

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Language：Japanese   Presentation type：Oral presentation (general)  

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Type：Lecture

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