著者

吉野 真史 丸山 和英 木村 克俊

出版者

公益社団法人 土木学会

雑誌

土木学会論文集B2(海岸工学) (ISSN:18842399)

巻号頁・発行日

vol.67, no.2, pp.I_1246-I_1250, 2011

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A person in a shallow beach near shoreline at Moheji Coast in Hokkaido died due to wave that had ordinary height in November, 2008. In order to reproduce the situation of the fall accident in a shallow beach, two-dimensional hydraulic model tests and numerical calculation were carried out to examine the wave force on a human body. The fall limit ratio was newly proposed for estimating the qualitative risk of person's fall accidents, and its applicability was confirmed. Based on these results, possibilities of person's fall accidents with ordinary waves were confirmed, and the safety tide level was shown for some wave conditions. A basic idea of the safety management was also proposed for shallow beach.

著者

湊 太郎 横山 由香 大石 友彦 佐藤 義夫

出版者

公益社団法人 土木学会

雑誌

土木学会論文集B2(海岸工学) (ISSN:18842399)

巻号頁・発行日

vol.68, no.1, pp.54-59, 2012 (Released:2012-10-19)

参考文献数

26

被引用文献数

1

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豊かな水産資源を効率的かつ持続的に利用するためには,より健全な沿岸海域環境を取り戻し,それを長期にわたって維持する必要がある.本研究では,海域環境改善の手法として,底質に光を照射し付着藻類の光合成を促すことにより,底層水の貧酸素化を抑制する方法に着目した.ここではまず,無酸素状態からの溶存酸素量の増加の可能性を調べるため,自然堆積物を用いて室内実験を行った.人工光源として,本研究ではLEDを採用した.その結果,光を照射することによって,溶存酸素量が増加し無酸素状態を脱することが確認された.このことから,底質にLEDを用いて光を照射する方法は,無酸素状態の環境を改善するために非常に有効な手段であることが明らかとなった.

著者

根本 信 高瀬 嗣郎 長谷部 大輔 横田 崇

出版者

公益社団法人 土木学会

雑誌

土木学会論文集B2(海岸工学) (ISSN:18842399)

巻号頁・発行日

vol.65, no.1, pp.346-350, 2009 (Released:2010-03-05)

参考文献数

15

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With the progress of recent seismological research, we have understood that slip distribution of earthquake fault rupture is generally heterogeneous and has fault asperity. However this heterogeneity of fault slip has not been considered enough in scenario earthquakes of tsunami prediction. In this study (1) we performed inversion analyses of past three large earthquakes in Japan sea (1964 Niigata, 1983 Nihonkai-Chubu and 1993 Hokkaido Nansei-Oki) using tsunami height data in order to investigate the characteristics of slip heterogeneity, (2) based on the inversion results, we proposed a modeling procedure of fault asperity on tsunami source model of scenario earthquakes.

著者

加藤 史訓 野口 賢二 諏訪 義雄

出版者

土木学会

雑誌

土木学会論文集. B2, 海岸工学 (ISSN:18842399)

巻号頁・発行日

vol.68, no.2, pp.1396-1400, 2012

著者

Hideaki YANAGISAWA Toyohiko MIYAGI Shigeyuki BABA

出版者

Japan Society of Civil Engineers

雑誌

Journal of Japan Society of Civil Engineers, Ser. B2 (Coastal Engineering) (ISSN:18842399)

巻号頁・発行日

vol.66, no.1, pp.251-255, 2010 (Released:2010-11-09)

参考文献数

11

被引用文献数

1 1

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We investigated tsunami mitigation effect of mangrove forest in 2009 Samoa tsunami using field survey and numerical model. Field surveys revealed that the wetland with 100 m width of mangrove forest reduced 80 % of tsunami inundation depth. We also found that mangrove forest significantly prevented tsunami debris from damage on the village behind forest. We modeled the propagation of 2009 Samoa tsunami and compared the numerical results with observed data. As results the numerical results are approximately consistent with the measured data. Using the numerical simulation of tsunami including the resistance of a mangrove forest we investigated the tsunami reduction effects of the mangrove forest in Samoa Island.