About 60,000 fires occur per year in Japan. Of them, over 30,000 cases were building fires. And burnout floor area is about 1,500,000 m² per year. It is preferable to decrease the number and scale of fires. The purpose of this study is to analyze the behavior of fire and its spread. To analyze them, we used fire statistics which is available to the public. At the beginning, the object region was the whole of Japan. The second object is Government-decreed cities and Tokyo's 23 wards. We analyzed the rate which is the fire spread and non-fire spread. Next there search was the correlation between the burnout floor area of the fire origin building and the burnout floor area of buildings damaged by fire spread. The result shows that the Fire spreading is not a special thing as the side of the month. The burnout floor area increases as the number of burnt buildings increases. It is different from each region that the calculation guidelines about burnout floor area. There is poor correlation between the burnout floor area of the origin building and the burnout.

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We investigated both lifestyle and energy consumption of 626 university students in Tohoku area by questionnaire surveys to assess energy conservation behaviours and energy consumption of one-person households. As a result, the following observations were obtained: 1) The percentage of possession of most appliances for one-person households, with few exceptions, was as high as the percentage for one-family households. 2) The difference in household type affected energy conservation behaviours and temperature in living room. 3) The annual energy consumption of one-person households varied in the characteristic of house occupant such as university students and workers.

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The Japanese government is funding public school facilities to apply green renovation for reducing environmental load and improving indoor environmental quality. Questionnaire survey on current classroom environment was conducted for 2,138 teachers in elementary and junior high schools across Japan. Thermal environment of classrooms was voted to be hot in summer and cold in winter, with higher discomfort votes in summer. In classrooms without heating, 90% voted the room to be cold in winter even in southern areas of Japan such as Kyushu. Direct sunlight in classrooms was voted to be glary by 48% of the teachers while 70% switched on artificial lighting at all time during the class. Teachers in open-type classrooms were more sensitive to noise from neighboring classrooms than teachers in closed-type classrooms. Indoor air quality was not rated to be a problem, although ventilation systems are rarely installed in classrooms. Green renovation schemes need to take into account the potential needs to improve indoor environmental quality as well as reduction of environmental loads.

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Reverse simulation, which is the solution of the transport equation in negative time, is a method for identifying pollutant source with CFD. Then the negative diffusion amplifies numerical errors and reverse simulation cannot be carried out. We proposed a method for improving numerical stability ⁽⁹⁾. This method applies a low-pass filter operation to concentration flux in RANS (Reynolds averaged numerical simulation)
In this paper, for application of actual problems, we introduce reverse simulation result in cavity flow, which has greatly-bent streamline and forms complex flow. In addition, we survey the dependence of reverse simulation accuracy on grid resolution and filter width.

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