The purpose of this study is the establishment of train safety in the case of large-scale earthquake, considering the derailment of Joetsu Shinkansen in 2004.
 Strengthening Tokaido Shinkansen structures to prevent long-time suspension of operation is nearly completed. As a result of this study, double measures against derailment and deviation were added and have been done.
 In this paper, we report the performance, the design, and the adaptability to the current railway of "Anti-Derailing Guard Rails". This study contributes to the safety of railway system.

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 The authors developed a stand-alone ground disaster monitoring station equipped with photovoltaic cells and packet communication tools for observing ground disasters. The system is equipped with a monitoring function for power generation and charge, remote control function for power consumption and automatic shutdown and reboot function for protection of measuring devices in order to ensure stable observations under unstable photovoltaic conditions. Through various test runs this system's performance was verified according to design concepts. This system has been determined to be stable for a stand-alone disaster monitoring station for situations where it is difficult to maintain power grids or communication networks.

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 Labour accidents in disaster-relief and disaster restoration work following the Great East Japan Earthquake (2011) were researched and analysed in order to raise awareness of the risks and hazards in such work, over a time period from the occurrence of earthquake up to a 18 months afterwards. In the construction industry, the characteristic accidents resulting in deaths and injuries are "Others," which includes disposal of rubble and demolition of buildings. In the building work, the predominant type of accident is a "fall to lower level," which increases mainly due to the fact that labourers are working to repair houses and buildings. And in the civil engineering, the predominant type of accidents is a being "caught in or compressed by equipment," due to the fact that working areas are limited in terms of space and subject to over-congestion. congested and limited. In addition, the number of the accidents classed as "fall to lower level" in the building work correlates closely with the number of partially damaged houses in disaster-affected areas.

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 This study uses as reference the conventional method of slope failure risk evaluation using a support vector machine, and assumes cases in which only a small number of the study data required for analysis is available. An attempt was made to propose a method of analysis using virtual data as a way of complementing such scarcity of training data.
 As a result of analysis, it became possible to construct separated surfaces with high precision by avoiding the expansion of contradictory data in the preparation of the virtual data and setting the parameters of the support vector machine in such a way that the number of times of additions/expansions of the virtual data is made as many as possible. Further, by using separated surfaces obtained from these virtual data, it became possible to evaluate slopes for which previously judgments of safety/risk could not be made. In addition, it was confirmed by site surveys of these slopes that there is agreement between the findings obtained from actual site conditions and the results of analysis obtained in this study, indicating the usefulness of the method.

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 The present study is to estimate the reliability for the seepage failure of the levee considering the uncertainty of the geotechnical characteristic and the probability of occurrence of the floodway water level in a year at the same time. It has aimed to calculate the annual probability of the levee failure caused by the circular slide due to the rise of water level. For this purpose, the fragility curve was first obtained by the probability of the seepage failure using the stochastic finite element method incorporating the uncertainty of shear strength. Furthermore, the hazard curve of the annual exceedance probability derived from the observational data of the floodway water level was determined. Using these results, the annual probability density of the failure of an existent levee under each water level and the annual probability the failure were calculated. Based on these results, it is suggested that the safety of the levee is able to be made quantitatively evaluated by the reliability index and/or the failure probability.

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