Ryota TSUBAKI
Research interest: 研究テーマ
High resolution inundation flow simulation and its application to mitigate physical and environmental risks: 高解像洪水氾濫流解析と、その解析で評価される洪水氾濫流の水理特性に着目した物理的被害や環境への影響の評価と緩和
Keywords: LiDAR, DEM, Finite volume method, Unstructured grid, railway, urban, mountainous
Advanced field monitoring of fluid flow and sediment transport: 河川の流れ・土砂・物質輸送の実測方法の開発と発展
Keywords: Flow visualization, acoustic, pressure, sediment transport, turbulence, gravel bed rivers
Understanding and control of river geomorphology: 河川の地形変化の予測と制御
Keywords: Gravel bed rivers, vegetation, numerical simulation
Recent activities
Visited the lab of Dr. Atsushi Nakano at Miyazaki University
Visited Miyazaki University in January 2025 to meet Dr. Atsushi Nakano, who had returned from his sabbatical at UC Irvine. The campus is spacious, green, and has an undulated topography. It reminds me of the campus of Hiroshima University, where I worked as an assistant professor.
The Gokase River, Omaru River and Oyodo River visit (JSCE, 基礎水理部会) Jan. 2025
Takachiho at the upstream of the Gokase River
Dakeku Bridge in the Omaru River, planned to be replaced.
Transplanted Penthorum chinese タコノアシ at the downstream of the Oyodo River
Fruit of cycad plant
Toxic and inedible.
川のふるさと交流館 さらら
2024.12に北海道旭川のこちらの施設を訪問し，流量観測に関する勉強会に参加しました．
味噌ラーメン
旭川名物！
北海道へそ祭り 人形
なんで大きな帽子を被っているのかが分った！
Visited Gifu with Prof. Cooper from UK
Prof. Cooper from Liverpool visited Nagoya, and we went to Gifu to explore the Kiso and Nagara Rivers on Dec. 2024. We also visited the river restoration research center (see the left photos).
Study supervision
Funding and research proposal of master's, doctoral and post-doctoral studies
Hiring master's and doctoral students for research projects is not very common in labs in Japanese universities.
Those interested in joining us will either have to pay your expenses or apply for a scholarship. Scholarships are either private or public.
For post-doctoral study, JSPS provides postdoctoral fellowships.
Self-driven research projects are quite important in master's and especially doctoral course. Accordingly, the research proposal by the applicant is quite important. I can advise but the proposal must be prepared by the applicant.
To consult on the master, doctoral, and post-doctoral studies, send your research proposal and C.V. by e-mail.
Description of selected papers
Image motion analysis of sediment particles migrating on dunes
Tsubaki, R., Baranya, S., Muste, M. and Toda, Y.: Spatio-temporal patterns of sediment particle movement on 2D and 3D bedforms, Experiments in Fluids, Vol. 59, No. 93, 2018. Post-print, View-only-version.
Flood Risk Assessment of the Middle Reach of the Helmand River, Afghanistan
K Sefat, R Tsubaki: Flood Risk Assessment of the Middle Reach of the Helmand River, Afghanistan, Journal of Disaster Research 19 (2), 455-464, 2024. Journal link.
A glacial lake outburst flood risk assessment for the Phochhu river basin, Bhutan
T Wangchuk, R Tsubaki: A glacial lake outburst flood risk assessment for the Phochhu river basin, Bhutan, Natural Hazards and Earth System Sciences 24 (7), 2523-2540, 2024. Journal link.
Effects of vegetation distribution along river transects on the morphology of a gravel bed braided river
R Zhu, R Tsubaki, Y Toda: Effects of vegetation distribution along river transects on the morphology of a gravel bed braided river, Acta Geophysica, 72 (2), 1097-1112, 2024. Journal link.
Impact Assessment of Flushing Flow from a Dam to Invasive Aquatic Plant Egeria densa in a Gravel-bed River
R Tsubaki, Y Kawahara, Y Mizuguchi: Impact Assessment of Flushing Flow from a Dam to Invasive Aquatic Plant Egeria densa in a Gravel-bed River, KSCE Journal of Civil Engineering 28 (3), 1062-1074, 2024. Journal link.
Experiment to clarify the condition of railway embankment scour
Tsubaki, R., Kawahara, Y. and Ueda, K.: Railway embankment failure due to ballast layer breach caused by inundation flows, Natural Hazards, Vol. 87, No. 2, doi: 10.1007/s11069-017-2789-3, 2017, Post-print, Journal link.
Fragility curve for railway embankment scour
Tsubaki, R., Bricker, J.D., Ichii, K. and Kawahara, Y.: Development of fragility curves for railway embankment and ballast scour due to overtopping flow, Natural Hazards and Earth System Sciences, EGU, Vol. 16, 2455-2472, doi:10.5194/nhess-16-2455-2016, Paper.
Sediment budgeting using detailed bathymetry maps: Acoustic mapping velocimetry (AMV)
Muste, M., Baranya, S., Tsubaki, R., Kim, D., Ho, H., Tsai, H. and Law, D.: Acoustic mapping velocimetry, Water Resources Research, Vol. 52, doi: 10.1002/2015WR018354, 2016.5, Journal link, Paper.
Spatial interpolation of river ADCP data
Tsubaki, R., Kawahara, Y., Muto, Y. and Fujita, I.: New 3-D flow interpolation method on moving ADCP data, Water Resources Research, Abstract, Paper, Repository
Development of image based flow measurement method and utilization to open water flow analysis
Multi-camera large-scale particle image velocimetry
Tsubaki, R.: Multi-camera large-scale particle image velocimetry. Measurement Science and Technology, doi: 10.1088/1361-6501/ab85d5, 2020, Post-print, Journal link.
On the Texture Angle Detection Used in Space-Time Image Velocimetry
Tsubaki, R.: On the Texture Angle Detection Used in Space-Time Image Velocimetry (STIV), Water Resources Research, Vol. 53(12), doi: 10.1002/2017WR021913, pp.10908-10914, 2017, Post-print, Journal link.
Smartphone apps for river flow measurement (LSPIV apps for iOS and Android)
Tsubaki, R., Fujita, I., Yu, K. and Muste, M.: Large-scale particle image velocimetry (LSPIV) implementation on smartphone, Proceedings of 36th IAHR congress, ISBN: 978-90-824846-0-1, Paper number 3874 on WEB site, Hague, Netherlands, June 28, 2015. Link
Innovation on river monitoring and its application on eco-hydraulics assessment
Development and refinement of methods for measuring water and sediment flow during floods, and assessment of those impact of river ecosystem (riparian and aquatic plants and attached algae)
Compact geophone
Tsubaki, R., Kawahara, Y., Zhang, X and Tsuboshita, K.: A new geophone device for understanding environmental impacts caused by gravel bedload during artificial floods, Water Resources Research, Vol. 53, doi: 10.1002/2016WR019726, 2017, Journal link, Paper, Post-print.
Flood inundation flow modeling
Railway embankment overtopping
Uncertainty assessment of the calculated result
Tsubaki, R. and Kawahara, Y.: The uncertainty of Local Flow Parameters During Inundation Flow Over Complex Topographies with Elevation Errors, Journal of Hydrology, Vol.486, 2013. Journal link, Repository
Mesh generation using LiDAR data
Tsubaki, R., Fujita, I.: Unstructured grid generation using LiDAR data for urban flood inundation modelling, Hydrological Processes, Vol. 24, No. 11, pp. 1404-1420, 2010, Abstract, Paper, Repository
Investigation of flow in a channel in Japanese garden
Tsubaki, R., Nakayama, Y. and Fujita, I.: The design secret of Kyokusui-no-En's meandering channel, Journal of Visualization, Vol. 11, No. 3, pp. 265-272, 2008.7. Abstract, Repository