In performance-based fire safety design of buildings, design fires are assumed based on relatively coarse information on potential combustible objects described by the object name, weight, size and main constituent materials. Then the fire effect is calculated by using assumed design heat release rate (HRR) to judge appropriateness of fire safety provisions. For this purpose, a simple estimation method of design HRR curve (whole time history of HRR) was developed by statistical correlations. The method is based on collection of available experimental datasets of various combustibles, which were categorized into two groups, wooden-combustibles and plastic-combustibles. To describe characteristics of HRR curves, parameters were correlated with properties of combustibles. Fire growth rate was correlated with bulk density of object. Maximum HRR and total heat release (THR) were correlated with surface area and weight, respectively. Fire decay rate was averaged over datasets in each group. By using the proposed methods, it is possible to establish a simple formula to represent full HRR diagrams of each category group. The accuracy of estimation was examined against whole datasets, which is in the order of two. By increasing the parameter values with one standard deviation, it is possible to make conservative estimation to include more than about 80 percent of experimental datasets.

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Today, smoke eliminating equipments which are going to work at a fire are adopted at a lot of subway stations in Japan. But there is some possibility of not working at a fire. So we think that designing a new fire safety system will improve the reliability of fire safety. Solar chimneys and Dry mist equipments which are studied in recent years are installed in our system (named passive safety system). So passive safety system can usually control the movement of air in the subway station as outside → a staircase → a platform (or concourse) → a solar chimney → outside. Smoke will be discharged from a solar chimney and safety of staircases will be kept at a fire. We made experiments based on scaling laws using 1/20 scale model of a subway station to understand the movement of smoke at a fire in a subway station. In addition to the model experiments, we simulated the movement of smoke using CFD software.

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In order to predict the level of vibration and structure-borne sound of a building near the railway tracks, it is essential to investigate vibration propagation from the ground to the foundation of the building. In this paper, a study is described on the property of vibration propagation based on a large-scale model test. The test model consisting of a structure and a tunnel was constructed on the ground and a series of forced vibration tests were conducted. Simulation analyses have then been performed by using two and three dimensional finite element methods. Finally, a simple prediction method of vibration propagation from the ground to a piled foundation has been proposed based on the study.

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This study aims to verify the relation between the oppressive feeling caused by single building and group of buildings and physical factors by regression analysis. For this purpose, questionnaire surveys were performed in field experiments. The results of the study are as follows. At first, the aspect ratio calculated from the proportion of a building facade has an effect on the oppressive feeling. It is considered to be the important physical factor in evaluation of the oppressive feeling by single building. Secondly, in case of single building, the configuration factor is a representative physical factor in an evaluation of the oppressive feeling. Besides, in case of group of buildings, the direction of eyesight faced to the buildings also has influence on the oppressive feeling. Therefore, it was ascertained to be difficult to explain the oppressive feeling only with configuration factor in urban space.

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A procedure is described for evaluating the solar reflectance of building materials by using a spectrophotometer. The point is that one should use the calibrated diffuser as a standard reference for reflectance; values of sample reflectance measured with a calibrated polytetrafluoroethylene resin (PTFE) are most reliable. Pressed barium sulfate, which is widely used in colorimetry, is not adequate as a standard reference for measuring the solar reflectance.

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The purpose of this study is to develop the ECO-insulator, which has thermal, humidity control and fireproof performance, for another to utilize agricultural wastes: rice-straw and chaff. Firstly, material properties of this ECO-insulator were measured and next, numerical simulations using these material properties were performed and the results of this ECO-insulator were compared with cases of Glass Wool and Extruded Polystyrene. The results are as follows; 1) Thermal performance of the insulator was more than one of Giass Wool 10K. 2) The fireproof performance was equivalent to one of Quasi-noncombustible Materials. 3) Without layer of vapor-barrier, it is pcssible to stop the dew condensation in the insides of walls, because of humidity control performance of this insulator.

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It is possible that the fresh air is carried into a room with a single-sided opening, where airflow is induced parallel to the plane containing the opening. However, when one room at windward side has contamination source in itself, it is possible that the airflow including contaminated air reaches openings of other rooms at leeward side. In this study, the characteristics of cross contamination to a leeward opening due to a windward opening are analyzed through wind tunnel experiment. In some experimental cases, the shape of opening is changed in order to determine the relationship with the cross contamination. The shape of windward opening is important factor of the cross contamination. In other experimental cases, square bars are attached in order to prevent the cross contamination. The room mean concentration with square bars shows a 30% decrease compared to the case without square bars.

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The cogeneration system (CGS) was positively introduced in terms of economy during the bubble economy period in Japan. Considering the issues of fossil fuel resource depletion and global warming, the next logical step would be reviewing the introduction of the CGS in terms of energy conservation. To examine the energy conservation effect of the CGS on the actual situation, we researched the operation situation of the gas engine CGS on Keio University Shonan Fujisawa Campus from November 2004 to October 2005. As a result, the energy conservation effect of the CGS does not reach its maximum, due to insufficient use of the exhaust heat in air conditioning systems. To enhance the effectiveness of the CGS, we examined the air conditioning systems, where the exhaust heat can be mutually reutilized among the air conditioning systems, and indicated the possibility of reducing the primary energy consumption and carbon dioxide emission through the use of the CGS.

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The authors have advanced the development of a calculating method for the time series loads of cold and hot water consumption by the Monte Carlo simulation technique. The purpose of this study is to obtain the fundamental data of the hot water consumption in the restaurants. The measurements of hot water consumption were carried out in 7 restaurants in each season. As for the measurement data, the time series loads of hot water consumption were analyzed. As the results, the relationships between the daily hot water consumption and number of customers were clarified. The fluctuation patterns of the hourly hot water consumption were classified into 3 types by cluster analysis. Finally, by using the measurement data which recorded by the interval of 2 seconds, calculation models of hot water consumption were proposed in each restaurant.

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Utilization of passive cooling effects by land and sea breeze circulation is considered to be very effective for reducing summertime air temperature in urban areas, because most of the major cities in Japan have developed in the costal area. Before the advance of the super computers, it had been difficult to simulate the airflow field of urban areas, with taking into account various scales of urban structures, such as buildings, streets and rivers. In this study, the Earth Simulator was used for the urban environmental analysis for the first time. We developed a new thermal environmental analysis system, which can deal with the atmospheric environment from individual building scale to urban scale. Using this code by incorporating the Coriolis force and potential temperature, we simulated the thermal environment in the ten-kilometers square area of central Tokyo with 5m grid spacing. As a result, regions with lower wind speed and higher air temperature were found aound high-rise buildings. It was also confirmed from the computed and observation results that airflow exists along the Nihonbashi-river and Megro-river. As for the air temperature, temperature distribution near the ground obtained from the computational results matched fairly well with that of observation, and the RMS error between observation and numerical results of 173 points was 1.1℃.

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This study is an attempt to reveal the microclimate on the loop and radial roads whose shape has been maintained since the early 20th century, in Hahoe, a traditional folk village in Korea, by field survey after confirming the characteristics of the regional climate. As the results show, the shape of the loop and radial roads which has earthen walls or the walls of earth and stones with an average height of 1.8 m on one or both sides, seemed to affect the winter microclimate in the loop and radial roads positively but the summer microclimate in some parts of the loop and radial roads were affected negatively. In addition, some parts of the loop and radial roads with a low ratio of wind velocity in summer seemed to have minimized adverse condition, because it is protected on both sides by the large crown of trees and earthen walls.

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This paper presents the findings of a questionnaire survey on usage of air-conditioners and windows among selected households in apartment houses in Johor Bahru City, Malaysia and compares the results with those in terraced houses surveyed previously. The frequency of respondents who open their windows during the nighttime in apartment houses was higher by 20% than that in terraced houses. However, this did not directly contribute to reduce the use of air-conditioners in apartment houses. It is especially important to find out the means to reduce both numbers and use of air-conditioners directly in order to help achieve energy-saving objectives in Malaysian residential areas.

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This paper described the simulation tool to evaluate energy management level of buildings for business use. The annual energy consumption can be easily estimated for various types of office buildings by this tool, of which input parameters are related with the building services and end-use conditions. This tool is user-friendly because the Input & Output Unit is developed in order to simplify the operations. Although this simulation program simplified on the basis of HASP/ACLD and BECS/CEC/AC does not need the numerous and the detail input parameters, the annual thermal loads and the annual energy consumption of air-conditioning systems for each simulated building can be calculated with the same accuracy as those by HASP/ACLD and BECS/CEC/AC. Any other energy consumption for each building service can estimated by using prediction formulas derived by the multiple regression analysis through the research conducted in order to keep track of actual conditions. Furthermore, the tool has extensive characteristics to be versatile in order to accommodate any future changes required for systems.

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The purpose of this study is 1) to clarify variations in moisture of soil around a tree, 2) to determine parameters of soil moisture stress function by measuring diurnal variations in stomatal conductance of wet soil and dry soil. The results show that : 1)the determined parameters are applicable to estimation of decline in stomatal conductance by soil moisture streess. 2)stomatal conductance declines to around a half of wet soil on fifteen days in a month.

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