Quantum Zeno Effect for Exponentially Decaying Systems

The quantum Zeno effect -- suppression of decay by frequent measurements -- was believed to occur only when the response of the detector is so quick that the initial tiny deviation from the exponential decay law is detectable. However, we show that it can occur even for exactly exponentially decaying systems, for which this condition is never satisfied, by considering a realistic case where the detector has a finite energy band of detection. The conventional theories correspond to the limit of an infinite bandwidth. This implies that the Zeno effect occurs more widely than expected so far.Comment: 4 pages, 3 figure

A GIS-based Support Tool for Exploring Land Use Policy Considering Future Depopulation and Urban Vulnerability to Natural Disasters – A Case Study of Toyohashi City, Japan -

AbstractIn Japan, where the aging society is progressing due to depopulation and a high risk of natural disasters, such as earthquakes and floods, many actual urban master plans (MPs) do not consider the relation between countermeasures for future depopulation and disaster mitigation. Local governments do not regard long-term depopulation as a viable opportunity to establish land use policy that promotes reasonable land use by aggregating urban land use to areas with low risk.This paper proposes the development of a tool for the exploration of land use policy that realizes an intensive urban structure by considering future depopulation and urban vulnerability to natural disasters. The tool serves as a GIS-based database of information about disaster risk for floods and earthquakes, future populations, previous and existing urban land use conditions, urban structures. The following results are obtained from a case study. First, experts such as local government can distinguish areas with high risk by two types of areas: 1) areas characterized by a slow progression of depopulation and aging and 2) areas in which it is difficult to sustain the local community and provide public services due to the progression of depopulation and aging. The results of this study can confirm various data on urban structures, such as transportation infrastructure, and core urban areas that provide life services and land use history. Reasonable land use countermeasures for reducing disaster risk can be explored by considering previous and existing conditions of urban land use

An Evacuation Simulator for Exploring Mutual Assistance Activities in Neighborhood Communities for Earthquake Disaster Mitigation

Japan is at great risk of being struck by huge earthquakes. When a strong earthquake occurs, various other disasters such as fire, collapsing buildings, and road blockages simultaneously occur as a result. In such a situation, it is difficult to ensure that the local emergency activities by, for example, the public fire company and community volunteers, are sufficient. Considering this issue, mutual assistance among residents, such as firefighting, evacuating victims, and helping those in need of assistance to designated safety sites, is extremely important. This paper proposes the development of an evacuation activities simulator, considering the capability of mutual assistance under various earthquake disasters to support exploration of community-based activities. In particular, the simulator calculates the time that local resident agents take to evacuate to the designated safety site, and the number of agents that can and cannot evacuate. Users can change the ratio of those who cannot evacuate to the designated safety site based on whether they are without some support or with persons who support them. Therefore, users can compare the simulation results of various outcomes. Through the experimental demonstration the following findings were obtained. Confirming the simulation results, users can understand that human suffering is reduced by mutual assistance activities. In addition, users can distinguish when the capability of mutual assistance is high or low, and when the capability of mutual assistance is changed according to the time of day due to the presence of the commuting population. Therefore, users can explore the countermeasures used to reduce human suffering when the capability of mutual assistance is low

Trends in Urban Planning and Measures of Disaster Risks in Japan - Roles of the Activities for Disaster Mitigation by Using Planning Support Systems

Based on the history of urban form and the history of disasters, and the current issues in Japanese society such as depopulation and expansion of the cities in the areas with high disaster risk, the formation of a compact city with safety to natural disasters is required. To realize the sustainable cities mentioned above, the necessity for plans and activities to (1) induce residents from areas with high disaster risk to safer areas with long-standing perspectives, (2) to improve the safety of areas that promote induce residence and increase population density, and the areas with the difficulty of induce residents are explained. As one of the means to support such plans and activities, the importance of the development and utilization of planning support tools was shown. Especially, through some examples, it showed the usefulness for substantiating discussions and considering safe and sustainable urban structures

Synthesis and Properties of Polysilsesquioxanes Having Ethoxysulfonyl Group as a Side Chain

Polysilsesquioxane having an ethoxysulfonyl group as a side chain was synthesized to prepare a proton-conductive film composed of a main chain of siloxane. At first, sodium 4-(2-methylallyloxy)benzenesulfonate was chlorinated with thionyl chloride. Next, hydrosilylation with trichlorosilane was carried out in the presence of platinum catalyst followed by treatment with ethanol. Finally, the hydrolytic polycondensation was carried out to provide poly(3-(4-ethoxysulfonylphenoxy)-2-methylpropyl)silsesquioxane. This polysilsesquioxane was heated to form a free-standing film that was brittle and brown in color