Mechanical fire resistance of internal load bearing walls under both-sides heating is important for the prevention of collapse of a dwelling in a fire. Feasibility of the 45 minutes mechanical fire resistance with Japanese traditional timber-frame soil internal wall is studied for this purpose. The tests were initiated with intermediate scale specimens for the examination of the charring and internal temperature field of the column and then loaded tests under both-sides exposure were conducted on two 1-story tall bare-timber wall specimens. The tests suggest significant influence of the mortises of columns for horizontal timber bars on the buckling of walls. The conventional predictive method of the mechanical fire resistance of bare timber walls is then modified for the tested configuration.

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The experiments on intelligibility, listening difficulty and optimum speech level by adjustment method were carried out under the condition of various noise level and reverberation. The following findings were obtained.
(1) The optimum speech level increases as noise level increases with inclination of less than 1.
(2) The level at which listening difficulty achieves minimum value in masking noise coincide with optimum speech level by adjustment method.
(3) The optimum speech level by adjustment method is not affected by reverberation, so it does not achieve sufficient intelligibility and listening difficulty in poor condition of reverberation and noise.

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Shading device is effective for reducing radiation load of buildings. Radiation load of buildings considering sky radiance distribution is different from that by isotropic model. RADIANCE is ray-tracing program and its accuracy is evaluated by some previous researches. In this research, RADIANCE installed sky radiance distribution model All Sky Model-R was developed. The transmission characteristics of external blinds evaluated by RADIANCE with isotropic model are compared with that with distribution mode in each sky conditions. Prediction error of annual insolation of building with external blinds by isotropic model is evaluated on the basis of that by sky distribution model. The evaluation results are introduced in this paper.

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The purpose of this paper is to identify the range of the total amount glare by using the average luminance of the visual field. Two series of experiments were carried out. In the first experiment , the pre-adaptation level equals the background luminance, and in the second, the pre-adaptation level is constant. The curve indicating the relationship between the luminance and glare sensation for the field with uniform luminance is obtained. The first experiment shows a significant difference in glare sensation, when the ratio of background luminance to source luminance is different, even when the average luminance of the visual field is the same. The second experiment shows that the effects of the ratio of background luminance to source luminance on glare sensation are not significant and that the average luminance can be used to predict glare sensation. The effect of the pre-adaptation level on glare sensation is also discussed.

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This paper describes a study on “exergetic” design method to efficiently utilize nutrient matter contained by domestic wastewater and its results. The followings were found. An algorithm to purify domestic wastewater and to efficiently utilize its nutrient matter is derived. Only in the case of purifying wastewater by the combination of soil and vegetation such as small wetland, if the area of a vegetation site is 5-13m² at least, exergy production by plants absorbing nutrient matter will exceed exergy consumption by a power plant and the other mechanical eguipment. Cascade use of domestic wastewater must be significant. A combined treatment septic tank or a multi-layering soil tank consumes “chemical exergy”, vegetation site fixes of chemical exergy and absorbs “concentration exergy”, and outdoor thermal environment is cooled by “wet exergy” consumption in summer. If the area of vegetation site is 20-40m² at least, exergy production by palnts will exceed exergy consumption by power plant and vehcles transporting compost on 50km/year.

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This paper described the distribution of contaminants (fine particle and bad smell from tobacco smoking) in the restaurant where the smoking seat and the non-smoking seat are arranged in the same space.
The results are as follows;
(1)When the smoking seats are in close formation near the exhaust outlet, the fine particle concentration from tobacco smoking is the lowest.
(2) It is very difficult to reduce bat smell intensity to the comfortable level, where smoking seats and non-smoking seats are arranged in the same space.

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Simpler and easier measurement method is required for ventilation rate. Improved PFT (Perfluorocarbon Tracergas) method by our group, which is a passive constant emission and passive sampling system, is applied in this paper. In order to verify the precision of PFT method, field measurements were conducted using three tracer gas techniques (PFT passive constant-emission, SF₆ constant-injection and CO₂ constant-concentration method) in a multi-family residential building with pressure control chambers. Differential pressures between indoor and outdoor were measured simultaneously and ventilation rates were calculated. Four measurement methods were applied simultaneously under four ventilation conditions. PFT method may include its unique errors referred from passive technique and might overestimate AERs (Air Exchange Rates) in cyclic reversal conditions of airflow. Under all other conditions except PFT method of condition 3, the results obtained from four methods agreed well with each other. In addition, as a result of the numerical calculation, the PFT method was suggested that it might have possibility to overevaluate a ventilation rate when the reversing cycle was relatively long over the stationary state arrival time. Under disturbance conditions except a long term cyclic reversal of airflow, however, the availability of PFT method for ventilation rate was verified.

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Various crimes have been steadily increasing and many people feel uneasy about public safety. Especially, the number of snatch occurrence in Osaka prefecture has been the top in Japan for the last 32 years, and it is a serious problem. This study aims to research relationships between road spatial factors and the occurrence of snatches by quantifying the spatial factors of roads.
In Abeno ward, Sumiyoshi ward and Higashisumiyoshi ward, belonging residential area, relationships between the occurrence of snatches and road spatial factors was studied. From the study, the reason why the rate of the occurrence of snatches is relatively lower in the area where visible distances of roads are from 25m to 50m can be explained by the types of snatches. And in the case of using bicycles, the number of the way to escape is emphasized in the snatch occurred in the narrow road.

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Fundamental evaluation of the performance field experiment and model experiment of air-conditioning system with floor thermal storage were analysed on following 3 aspects. 1)The temperature distribution to the floor slab was able to be confirmed by the distributed temperature sensor on the field measured data. 2)The domination of the system was able to be verified by understanding the building heat characteristic based on the comparison of a variety driving patterns. 3)The influence that the supply temperature and the supply distance gave to the amount of the thermal storage was able to be confirmed by the model experiment.

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In this paper, we carried out the field measurement in the urban district in Hiroshima City formed on the delta in Ohota River. We measured wind velocity and temperature in the sea breeze in the summer. We made an analysis of the relationship between the air temperature and the instantaneous wind velocity. Results are as follows.
In case of Eastern and Western Street near the river, there is the relationship between air temperature and the wind direction: the air temperature falls when it blows from the river. In case of the road at Northern and Southern Street on the inland, there is a correlation between air temperature and the instantaneous horizontal velocity. In case of the Eastern and Western Streets where there are many the high-rise buildings, there is a correlation between air temperature and the vertical velocity. The case on the bridge at Eastern and Western Street, there is a correlation between air temperature and the horizontal velocity.

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To promote ventilation in the street canyon is one of the effective heat island measures. The analysis on the relationship between properties of urban block and wind environment in the street canyon is required. In this study, relationship between wind environment in the street canyon and the direction of street, the width of street and the building height beside street is studied by CFD simulation result and observation result. Wind velocity ratio, which is calculated in street wind velocity by upper wind velocity, is used for the index of wind environment in the street canyon.

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It's very important not only to improve the structural capacity against an earthquake but also to secure the drinking water to survive through the situation of interrupted public water supply system just after the big earthquake disaster. It's well known where the places for disaster refuge are but not so known where the strage waters are and whether the strage waters are enough for water demand under the earthquake disaster. In this study, mesh analysis was carried out that was focused on the drinking water demand and supply in the situation of interrupted public water supply system for Miyagi prefecture. Water demand was estimated by population and water supply was surveyed for emergent water supply facilities. As the results, it was clarified that there were many water-insufficient districts, and by analyzing from the viewpoint of water demand density; population density, there were several characteristics of water insufficiency and countermeasures for each of them. Besides, it was shown that analyzing method of this study was convinient for considering effectual measures.

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This study investigates the effectiveness of night ventilation technique for residential buildings in hot-humid climate of Malaysia. The effects of different natural ventilation strategies on indoor thermal environment for Malaysian terraced houses are evaluated based on the results of a full-scale field experiment. The results show that the night ventilation technique lowers the peak indoor air temperature by 2.5°C and reduces nocturnal air temperature by 2.0°C on average, compared with the current window opening patterns, i.e. daytime ventilation. It can be seen that night ventilation would provide better thermal comfort conditions for occupants in Malaysian terraced houses compared with the other ventilation strategies. However, the indoor humidity control in the daytime such as by dehumidification would be needed when the night ventilation technique is applied.

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Construction waste, approximating 20% of the total amount of industrial waste, is a vital factor in controlling environmental load. In this study, our survey on the present practices of waste treatment is the basis for numerical data analysis, on which waste treatment are discussed with the focus on landfill and its CO₂ emission as potential in load reduction. Main contents are as follows;
1. Material flowchart on building waste treatment developed.
2. Environmental loads estimate for each type of waste treatment practice by inventory analysis.
3. Discussion made on estimate loads in view of environmental load reduction.

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