PHYSICAL AND NUMERICAL MODELING FOR DRIFT OBJECTS DUE TO TSUNAMI INUNDATION IN COASTAL URBAN AREA

Off the Pacific coast of Tohoku Earthquake and Tsunami, many ships, containers, cars, and wooden debris of collapsed houses were drifted by a huge tsunami. Their drift objects prevented the rapid elimination of obstacles and debris on land and sea. In addition, in areas where tsunami-fire occurred, accumulated wooden debris caused the large-scale fire spread. Generally, when assuming tsunami damages in urban areas, the inundation depth and arrival time of tsunami are mostly used. In order to enhance the tsunami damage assumptions in urban areas, to understand the characteristic of tsunami flow and the behavior of drift objects in urban areas is also important. However, it is very difficult to measure the state of actual tsunami flow and the behavior of drift objects by tsunami flow. This study aims to understand the characteristics of drift objects behavior in an urban area through a series of experiments in a laboratory flume. This study also validates numerical simulation model by comparing with the experimental results.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/09KWpiVSbmU

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Numerical Simulation of Tsunami Inundation in Urban Areas

Journal of Disaster Research ◽

10.20965/jdr.2006.p0148 ◽

2006 ◽

Vol 1 (1) ◽

pp. 148-156 ◽

Cited By ~ 1

Author(s):

Tetsuya Hiraishi ◽

◽

Tomohiro Yasuda ◽

Keyword(s):

Numerical Simulation ◽

Numerical Model ◽

Simulation Model ◽

Urban Areas ◽

Tokyo Bay ◽

Tsunami Inundation ◽

Model City ◽

Inundation Depth ◽

The Pacific ◽

Potential Damage

The population and property in urban areas facing waterfronts is rapidly increasing together with the probability that a huge tsunami will occur on the Pacific Rim. The huge potential damage reflects the need to develop a highly accurate simulation model for tsunami inundation to help mitigate tsunami effects. We developed a simulation model to estimate the inundation depth and speed of tsunamis in urban areas. The model was applied to calculate the vari- ation of inundation areas in a model city facing Tokyo Bay. Experiments of tsunami inundation in the model city on a 1/50 scale was carried out for validation of the numerical model.

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GNSS RUMS: GNSS Realistic Urban Multiagent Simulator for Collaborative Positioning Research

Remote Sensing ◽

10.3390/rs13040544 ◽

2021 ◽

Vol 13 (4) ◽

pp. 544

Author(s):

Guohao Zhang ◽

Bing Xu ◽

Hoi-Fung Ng ◽

Li-Ta Hsu

Keyword(s):

Urban Area ◽

Intelligent Transportation Systems ◽

Urban Areas ◽

Large Scale ◽

Transportation Systems ◽

Accurate Localization ◽

Gnss Receivers ◽

Multipath Signal ◽

Scale Test ◽

Error Behavior

Accurate localization of road agents (GNSS receivers) is the basis of intelligent transportation systems, which is still difficult to achieve for GNSS positioning in urban areas due to the signal interferences from buildings. Various collaborative positioning techniques were recently developed to improve the positioning performance by the aid from neighboring agents. However, it is still challenging to study their performances comprehensively. The GNSS measurement error behavior is complicated in urban areas and unable to be represented by naive models. On the other hand, real experiments requiring numbers of devices are difficult to conduct, especially for a large-scale test. Therefore, a GNSS realistic urban measurement simulator is developed to provide measurements for collaborative positioning studies. The proposed simulator employs a ray-tracing technique searching for all possible interferences in the urban area. Then, it categorizes them into direct, reflected, diffracted, and multipath signal to simulate the pseudorange, C/N0, and Doppler shift measurements correspondingly. The performance of the proposed simulator is validated through real experimental comparisons with different scenarios based on commercial-grade receivers. The proposed simulator is also applied with different positioning algorithms, which verifies it is sophisticated enough for the collaborative positioning studies in the urban area.

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SEISMIC RESPONSE ANALYSIS FOR FOUNDATION OF LARGE-SCALE STRUCTURE ON DISCONTINUOUS ROCK^|^mdash;AS A BASIC EXAMPLE USED THE 2011 OFF THE PACIFIC COAST OF TOHOKU EARTHQUAKE^|^mdash;

Journal of Japan Society of Civil Engineers Ser C (Geosphere Engineering) ◽

10.2208/jscejge.70.16 ◽

2014 ◽

Vol 70 (1) ◽

pp. 16-32

Author(s):

Ryunoshin YOSHINAKA ◽

Naoki IWATA ◽

Takeshi SASAKI

Keyword(s):

Seismic Response ◽

Large Scale ◽

Pacific Coast ◽

Tohoku Earthquake ◽

Large Scale Structure ◽

Scale Structure ◽

Response Analysis ◽

Seismic Response Analysis ◽

The Pacific ◽

Discontinuous Rock

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TSUNAMI INUNDATION SIMULATIONS IN URBAN TOPOGRAPHY

Coastal Engineering Proceedings ◽

10.9753/icce.v36.currents.62 ◽

2018 ◽

pp. 62

Author(s):

Takuya Miyashita ◽

Nobuhito Mori

Keyword(s):

Rural Areas ◽

Urban Areas ◽

Numerical Models ◽

Tohoku Earthquake ◽

The 2011 Tohoku Earthquake ◽

Tsunami Inundation ◽

Urban Topography ◽

Run Up ◽

Tsunami Run Up ◽

Local Momentum

The inundation of the 2011 Tohoku Earthquake Tsunami showed complex behavior over the land. According to the surveys of the Tohoku Earthquake Tsunami in 2011, the behavior of tsunami in urban areas was different from that in rural areas and the damage was not only dependent on the inundation heights but also the local momentum. The buildings are commonly excluded and smoothed off in the topography in the conventional inundation simulation but itâ€™s important to understand the local characteristics of tsunami run-up in urban areas. The purpose of this study is to understand and validate numerical models of tsunami in the urban area.

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GNSS RUMS: GNSS Realistic Urban Multi-agent Simulator for Collaborative Positioning Research

10.20944/preprints202012.0647.v1 ◽

2020 ◽

Author(s):

Guohao Zhang ◽

Bing Xu ◽

Hoi-Fung Ng ◽

Li-Ta Hsu

Keyword(s):

Urban Area ◽

Intelligent Transportation Systems ◽

Urban Areas ◽

Large Scale ◽

Transportation Systems ◽

Accurate Localization ◽

Multipath Signal ◽

Multi Agent ◽

Scale Test ◽

Error Behavior

Accurate localization of road agents is the basis of intelligent transportation systems, which is still difficult to achieve for GNSS positioning in urban areas due to the signal interferences from buildings. Various collaborative positioning techniques are recently developed to improve the positioning performance by the aid from neighboring agents. However, it is still challenging to study their performances comprehensively. The GNSS measurement error behavior is complicated in urban areas and unable to be represented by naive models. On the other hand, real experiment requiring numbers of devices is hard to be conducted, especially for a large-scale test. Therefore, a GNSS realistic urban measurement simulator is developed to provide measurements for collaborative positioning studies. The proposed simulator employs a ray-tracing technique searching for all possible interferences in the urban area. Then, it categorizes them into direct, reflected, diffracted, and multipath signal to simulate the pseudorange, carrier-phase, 〖C/N〗_0, and Doppler shift measurements correspondingly. The performance of the proposed simulator is validated through real experimental comparisons with different scenarios. The proposed simulator is also applied with different positioning algorithms, which verifies it is sophisticated enough for the collaborative positioning studies in the urban area.

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Deformation of Sandy Beach and Inundation on Iwama-Sanuka Coast in Fukushima Prefecture due to the 2011 Tohoku Earthquake Tsunami

Journal of Disaster Research ◽

10.20965/jdr.2012.p0476 ◽

2012 ◽

Vol 7 (sp) ◽

pp. 476-484 ◽

Cited By ~ 1

Author(s):

Takaaki Uda ◽

◽

Kazuya Sakai ◽

Yukiyoshi Hoshigami ◽

Yasuhito Noshi ◽

...

Keyword(s):

Sandy Beach ◽

River Mouth ◽

Tohoku Earthquake ◽

Field Observations ◽

The 2011 Tohoku Earthquake ◽

Tsunami Inundation ◽

Fukushima Prefecture ◽

Inundation Depth ◽

Miyagi Prefecture ◽

Mouth Bar

The massive earthquake with a magnitude of 9.0 occurred at 14:46 on March 11, 2011, with an epicenter 130 km offshore from the Oshika Peninsula in Japan’s northeastern Miyagi Prefecture. After the earthquake, large tsunamis were generated owing to abrupt crustal subsidence and uplift, which inundated Japan’s eastern Pacific Ocean coastline. We carried out field observations to investigate the deformation of a previous river-mouth bar by comparing oblique photographs, and investigated the damage to seawalls and the tsunami inundation depth on the Iwama-Sanuka coast, located north of the Same River in southern Fukushima Prefecture. Here, the results of the field observations on the deformation of the sandy beach and the inundation of the Iwama-Sanuka coast are reported.

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LASDU: A Large-Scale Aerial LiDAR Dataset for Semantic Labeling in Dense Urban Areas

ISPRS International Journal of Geo-Information ◽

10.3390/ijgi9070450 ◽

2020 ◽

Vol 9 (7) ◽

pp. 450

Author(s):

Zhen Ye ◽

Yusheng Xu ◽

Rong Huang ◽

Xiaohua Tong ◽

Xin Li ◽

...

Keyword(s):

Urban Area ◽

Urban Areas ◽

Point Cloud ◽

Large Scale ◽

Point Clouds ◽

Light Detection And Ranging ◽

Early Age ◽

3D Mapping ◽

3D Point Clouds ◽

Semantic Labeling

The semantic labeling of the urban area is an essential but challenging task for a wide variety of applications such as mapping, navigation, and monitoring. The rapid advance in Light Detection and Ranging (LiDAR) systems provides this task with a possible solution using 3D point clouds, which are accessible, affordable, accurate, and applicable. Among all types of platforms, the airborne platform with LiDAR can serve as an efficient and effective tool for large-scale 3D mapping in the urban area. Against this background, a large number of algorithms and methods have been developed to fully explore the potential of 3D point clouds. However, the creation of publicly accessible large-scale annotated datasets, which are critical for assessing the performance of the developed algorithms and methods, is still at an early age. In this work, we present a large-scale aerial LiDAR point cloud dataset acquired in a highly-dense and complex urban area for the evaluation of semantic labeling methods. This dataset covers an urban area with highly-dense buildings of approximately 1 km2 and includes more than three million points with five classes of objects labeled. Moreover, experiments are carried out with the results from several baseline methods, demonstrating the feasibility and capability of the dataset serving as a benchmark for assessing semantic labeling methods.

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