In this study, we calculated the probability of planned suspension for Toyohashi Railroad by analyzing past operational disruptions on the Atsumi Line and streetcars, coupled with typhoon data. Results were used to develop a formula for the probability of planned service suspensions 24 hours in advance when a typhoon struck. Regression analysis showed a 61.3% accuracy for rainfall warning criteria and 78.5% for wind speed. Suspension criteria accuracy was 58.2% for rainfall and 75.8% for wind speed. However, rainfall exhibited significant variability, suggesting the insufficiency of the two parameters in capturing the phenomenon. Future improvements may involve adding new parameters, such as storm radius, for a more accurate estimation equation.

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This paper focuses on the lack of input workers at basic municipalities as one of the reasons why disaster information systems do not function adequately, and discusses information sharing from field response agencies. Until now, the information grasped by field response agencies (fire departments, police, Self-Defense Forces, Japan Coast Guard) has been shared individually with prefectures and basic municipalities by exchanging printed materials. For this reason, each basic municipality needs to re-enter the information from the disaster response agencies into the disaster information system. Aiming to improve this situation, a demonstration experiment was conducted in disaster response drills in Aichi Prefecture. A disaster information system linked to SIP4D (Shared Information Platform for Disaster Management) was provided to each field response agencies, and information was directly shared. As a result, the effectiveness of direct information sharing from field response agencies and the issues for its realization were indicated. Furthermore, during the 2024 Noto Peninsula Earthquake, the system used in the above demonstration experiment was provided to field response agencies, demonstrating the effectiveness of information sharing by field response agencies.

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On February 6, 2023, M_w 7.8 and M_w 7.5 earthquakes occurred in the southeastern part of Turkey. In Golbasi, serious damages such as settlements and tilting of buildings due to liquefaction were observed. Differential settlement of buildings caused by liquefaction has been reported in past earthquakes, with the impact of loads from adjacent buildings being noted. This study examines the differential settlement behavior of adjacent buildings with shallow foundations in Golbasi. The variations in foundation embedment depth and weight of the buildings were also investigated. The results showed that closer buildings experience more internal settlement due to stress interference, leading to inward tilting. As the distance between the two buildings increases, the mutual interference decreases, resulting in a smaller tilting angle.

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This study explores residents' demand for necessary materials in the aftermath of the Nankai Trough Earthquake. We also analyze perceptions of periods of isolating conditions and obtaining relief materials after the Nankai Trough Earthquake and demand differences among characteristics of gender, age, unnecessary period for medical care service, and unnecessary period for medication used on a daily basis. The target area is the districts of Kirime area in Inami Town, Wakayama, Japan, including the tsunami inundation area by the Nankai Trough Megathrust Earthquake assessment. A questionnaire survey was conducted on residents in the research area between October 27 and November 28, 2023. The numbers of distribution and valid responses in this study were 674 and 237 (35.3%). Results indicated that food and toilet-related supplies are high-demand materials in residents’ perceptions, and the demands for adult diapers and cutlery in the attribute of high-need for medical care service are greater than those in other attributes.

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This paper aims to elucidate the challenges faced by school-aged children and their families during disasters. This paper analyzes interviews conducted at a relatively early- stage with parents in disaster-affected areas. The results revealed that the difficulties arose due to the closer proximity between parents and children and the loss of “Ibasho” for children. Parents faced heightened mental burdens and difficulties during recovery efforts while children's rights to play were infringed upon. Moreover, requiring parents to spend long hours with their children made it challenging for them to interact with each other in a relaxed atmosphere. To mitigate these challenges, this paper highlights the need for safe spaces with daycare functions and playgrounds with minimal restrictions free from the watchful eyes of others.

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This study qualitatively explored factors driving disaster prevention app adoption among Thai residents in Japan using the Constructivist Grounded Theory Approach. Interviews with ten Thai residents revealed individual factors like disaster awareness and self-efficacy driving app downloading. However, social interactions and cultural backgrounds within the Thai community, such as online influencers and information sharing, emerged as significant adoption drivers. For non-adoption, the findings shed light on language-proficient residents with alternative information access not necessarily downloading apps despite organizational recommendations. Non-adoption seemed influenced by a combination of organizational influence, individual language ability, information environment, and disaster awareness levels. Extending social cognitive theory, the results highlight sociocultural contexts playing a key role beyond individual cognitions alone in disaster app adoption and non-adoption among foreign residents. The study provides a theoretical basis for comprehensively understanding this phenomenon in minority communities.

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To enhance preparedness for sudden disasters, it is important for local governments to conduct exercises during non-emergency periods to promptly establish and effectively operate disaster management headquarters. However, many municipalities face challenges in conducting such exercises due to limited expertise and manpower for planning and implementation. This paper presents a case study of Tamba City in Hyogo Prefecture, which conducted a floodresponse exercise at its disaster management headquarters in 2020 through a collaborative effort between a university and the municipality. This paper analyzes the process, system, scenario development, exercise rules, and evaluation methods employed in this case. This analysis can serve as valuable reference material for other municipalities planning similar disaster management headquarters exercises.

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In the areas affected by the 2011 Tohoku earthquake and tsunami, efforts have been made to promote the dissemination of disaster learning. In this study, we aim to analyze which contents of learning and experiences effectively change their actions to reduce disaster risk according to visitors' preparedness, and the purpose of their visit. We conducted an online survey among visitors (N=1,175) to the disaster-affected areas from the 2011 event. The main findings are as follows: 1) visiting the interior of the earthquake ruins, seeing the townscape that was cleared, and listening to the storytellers were most effective regardless of the visitor's disaster preparedness or purpose; 2) informal and interactive interactions with locals who experienced the disaster may be effective for visitors less prepared with intention to learn the disaster.

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This study conducted three basic studies on evacuation on foot from lava flows during the Eruption of Mt. Fuji: 1) estimation of the population exposed to lava flows over time after the eruption, 2) development of a safety assessment method for evacuation on foot from lava flows, and 3) evacuation simulation based on the developed assessment method. Based on the results of these analyses, measures for safe evacuation on foot from the lava flow were discussed. The study showed that the maximum number of people exposed to the lava flow was about 2,000 3 hours after the eruption. The maximum number of people who had difficulty evacuating was about 800 when the evacuation start time was 75 minutes. On the other hand, the number of people who had trouble evacuating was smaller when evacuation was 45 minutes than when the start time was 75 minutes. This indicates that shortening the evacuation start time is essential for safe evacuation on foot from the lava flow.

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In this study, the applicability of a numerical model for the predicting of local scour at the downstream of a weir, which has been developed by the authors in the river field, to the local scour at the toe of a coastal dike induced by tsunami overflow was investigated. Furthermore, the influence of the difference between equilibrium and non-equilibrium bed load transport models on the reproducibility of the phenomenon was also examined. The results showed that the model was able to reproduce well both the tsunami overflow situation and the local scour progression with repeated flow regime transitions. Moreover, the non-equilibrium model reproduced a smooth scour shape extending from the top of the foundation as in the experiment, while the equilibrium model produced deep scour just below at the toe of the dike. In addition, it was also clarified that the coefficient of the suspended load formula had a significant effect on the reproduction of the phenomenon.

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This study reports on the practice of disaster education using letters as a medium in school disaster education, and discusses the importance of transferring disaster education learning to readers and the importance of practicing disaster education initiatives using letters as a medium. The results suggest that the letters written by children not only contain the content of what they have learned in disaster education classes, but also their will to be proactive in times of disaster and their messages to the readers of the letters calling for disaster reduction measures. It can be concluded that the degree to which the children's thoughts are conveyed to the readers through the letters is likely to be high, and that there is a high possibility of having a positive influence on the readers' disaster awareness and actions through a series of efforts.

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The predecessor of the Volcano Disaster Management Council under the Act on Special Measures Concerning Countermeasures for Active Volcanoes was the Aso Volcano Disaster Prevention Council, which was established in 1967 around Mt. Aso. The council established criteria for entry restrictions correspond to weather station information in its disaster prevention plan, and became the prototype for the current volcano disaster countermeasures under the Volcano Disaster Management Council. The purpose of this study is to clarify how the framework of the council mainly consisting of local governments was formed around Mt. Aso, and how the volcanic disaster countermeasures that predetermined the criteria for entry restrictions correspond to information from the Japan Meteorological Agency were shaped within that framework. The results show that, in the course of considering how to respond to repeated outbreaks of volcanic disasters, the related organizations on the mountain were confronted and conflicted with each other in the Council, leading to the strengthening of the countermeasures.

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In this study, numerical experiments using SCALE-RM on the cloud-seeding method for heavy rain mitigation considering multiple implementation conditions were conducted. The effects of heavy rain mitigation under various conditions such as seeding implementation time, altitude, and area were evaluated, and comparisons were made with previous studies using WRF regarding the heavy rain mitigation effects by cloud seeding. As a result, it was confirmed that both the accumulated maximum and time maximum precipitation decreased due to seeding implementation, and the mitigation effect at peak times was observed. Particularly, the largest mitigation effect was obtained when two steps seeding, and an analysis of the mitigation mechanism confirmed that the combination of two different mechanisms, the weakening of updrafts and the suppression of graupel growth, enhanced the heavy rain mitigation effect. These mitigation effects generally matched the results of previous studies using WRF, indicating a reliability improvement of heavy rain mitigation effects through cloud seeding.

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This study conducted numerical experiments of heavy rainfall mitigation under multiple experimental conditions using the Weather Research and Forecasting model (WRF) to investigate the effectiveness of Pinpoint-Seeding operation in linear convective systems. By examining the difference of mitigation effects among different seeding methods and implementation conditions, it was found that implementing Pinpoint-Seeding only in grids with strong updrafts resulted in a reduction of approximately 16.5% in maximum accumulated precipitation. This study also clarified the impact of seeding duration and implementation altitude on the mitigation effects. The mechanism of rainfall mitigation through the over-seeding condition, where the growth of ice crystals and snow reduces supercooled water droplets and then suppresses graupel growth, was confirmed by analyzing mixing ratio and number concentration of precipitation particles.

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Although various analyses have been conducted on the resident evacuation behavior by various viewpoints, it is still difficult to say that the problems related to the resident evacuation have been solved because of the number of victims caused by heavy rain disasters. Therefore, the authors have made a new attempt to analyze the factors of resident evacuation behavior using XAI (eXplainable AI). However, there are still issues such as the estimation accuracy of the behavioral model. In addition, previous analyses of resident evacuation behavior have often attempted to determine whether certain factors influence evacuation behavior. In this study, the prediction accuracy was improved by converting questionnaire survey data into image data and constructing a resident evacuation behavior model using a convolutional neural network (CNN). we analyzed the factors of resident evacuation behavior during heavy rain disaster by using Grad-CAM that is a method of XAI in image recognition technology. As a result, the combination of the following factors were found to influence evacuation behavior during a disaster: obtaining evacuation information from a trusted person, understanding disaster prevention information deeply, preparing emergency supplies, and discussing with family members.

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