Three scenarios for recycling of demolition wood waste from residential houses were compared in terms of the recycling rate and reduction of the new wood input. Respective scenarios included the incineration, recycling as raw materials for paper and wood composite board, and reusing as constructive members of residential houses. The results were as follows: 1) reuse of lumber as well as diverse use of wood waste chips were effective to reduce the amount of wood waste; 2) improving the reuse rate of lumber was effective to reduce both the amount of waste and the input of new wood into construction of houses; 3) an increase in the demand for wood waste chips reduced the amount of waste but did not greatly affect the input of new wood.

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Fire resistance tests are conducted on small-scale specimens of wood/soil wall assembly with different construction details as a basis for developing code-acceptable traditional wooden constructions. The tests have revealed significant influence of both-side plastering of soil wall, thickness and water content of the soil layer and various reinforcements of timber/soil layer interface on the prevention of the heat and flame penetration through a wood/soil wall. lt has been also clarified that charring of the timber element, a major cause for the collapse of the wall due to fire, can be reduced by the protection of the load-bearing timber elements by soil or wood or by design considerations reducing fire exposure of the timber element.

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For fire risk assessment, a probability prediction of fire behavior including a small fire to a large one is necessary. However most existing predicting models for fire behavior are considered some factors with dispersion as the decided values, called 'the worst conditions'. In this study, Monte Carlo simulation using a predicting model for fire behavior given two probability parameters, which were the limit heat release rate and the fire spread rate of each unit, was proposed to calculate the probability distributions of design fire. Then some case studies with the effect of fire protection measures were examined and the smoke temperature of the fire room as probability distribution were calculated.

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This paper presents 3-D analysis of wave propagation over the wide area, such as an urban block by use of boundary integral equation method(BIEM). By introducing a new response function using the mirror image with respect to the ground surface, which has arbitrary acoustic admittance, so that the element division of the ground surface becomes unnecessary, and the calculation load is mitigated. Therefore, it is enable to analyze a sound field complicated with diffraction, multiplex reflection, etc., in which the conventional geometric sound analysis method cannot give good accuracy.

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The objective of this study is to identify the effects of thermal and acoustic discomfort on glare sensation and manual control of venetian blinds. The results of subjective experiments in a test chamber with an artificial window are described. The room air temperatu re affected glare sensation a little, while noise levels did not affect glare sensation. However, the probability that subjects used the venetian blind was determined only by glare sensation. When the Glare Sensation Vote was 1(just perceptible), more than 50% of the subjects used the venetian blind. After the adjustment of the Venetian blind, glare sensation became lower in all conditions, but the room environment was not acceptable in the case of room air temperature being 29.5℃ because of thermal discomfort.

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The foundation insulated house has thermal effectiveness from the point of the high-airtightness and so on. However, there are many kinds of insulated foundation and these thermal performances are not clarified so far. Therefore, in this research, it examined the insulated performance of the foundation insulated house by the computational simulation. In addition, it presented the simple prediction model for evaluation of the heat loss around the basement of insulated foundation house and its validity.

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The vapor flux caused by temperature difference is estimated with calculation based on molecular dynamics. The thermal diffusion, which is defined in the couple with vapor flux caused by pressure gradient, has been expressed approximately by Chapman and Cowling in the extremely complicated numerical form. The literature survey shows that it has not clarified the degree of the approximation error and actual effect in and around the buildings. The calculation results supported by today's great CPU power shows good agreement with comparative reported results and the higher approximation has not great difference with the first approximated result. And the numerical results show that the thermal diffusion effect is negligible in actual building problems.

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Thc purpose of this report is to make a plume model above commercial use cooking stove to simulate environment of commercial kitchen by CFD. We measured the temperature, air velocity, turbulence energy, concentration of tracer gas of plume above gas and induction heating commertial cooking stoves at 0.5m to 1.5m high. In results, it is made clear that the shape of distribution in each section can bc expresssed Gaussian profiles, but it is difficult to predict value of commercial use cooking stove from value of domestic one.

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Recently, indoor air pollution by chemical substances generated from building materials, furniture and various utensils becomes a serious problem in Japan. Such indoor air pollution may be a cause of hazardous influence onto the occupants' health ("Sick-House-Syndrome"). In this study, indoor air quality of houses in Miyagi prefecture, Japan, where occupants are suspected of Sick-House-Syndrome, has been investigated during the summer in 2001. The investigation includes measurements of aldehydes and Volatile organic compounds (VOCs), questionnaire regarding subjective symptoms, examination and clinical test by medical doctors. As a result, the relationship between chemical substance concentration and the subjective symptoms by questionnaire suggested that the symptoms of the occupants become stronger in higher concentration houses, and, on the other hand, there are some occupants with heavy symptoms in low concentration houses.

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First, the authors performed the investigations on the released height of anthropogenic heat from HVAC system. The subjects of investigation are 203 buildings in the central city of Fukuoka and 111 buildings recorded in the database of HVAC system of a certain journals. From these investigations, following features are summarized. 1. The ninety percent of buildings with less than 5000 square meters of building area adopt the air-cooling type of heat disposal equipment, so-called cooling tower, which are mainly sited at the each floor level. 2. The fifty percent of buildings with more than 5000 square meters of building area adopt the water-cooling type of heat disposal equipment of HVAC system, which are mainly sited at the roof. Secondly, the investigation on the urban geometric figure was conducted using the GIS data of Tokyo and Fukuoka. The features of vertical distribution of both roughness volume density and building wall area density were classified with the gross ratio of building volume. And the histograms of building area, floor area, story, distortion factor and aspect factor are presented, which are grouped into 6 classed according to both the gross ratio of building volume and building plan area fraction.

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This paper is study about shadow diagram in city area. To analyze environmental thermal condition in urban area, one of major problems is effect of shadows of buildings. Using height data of buildings, shadows were calculated for a face at any date and any time. Two pixel sizes simulations were calculated about shadow of buildings in urban area, the results show 5m pixel size simulation didn't calculate shadows of houses exactly, but 1m pixel size simulation estimate good results about houses shadows. Diumal relative sunshine duration map and diumal solar irradiance map were calculated. To estimate a effect of shadows of buildings in urban area, each maps were confirmed their efficiency.

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Effects of attention on visual perception are investigated by means of analysis of visual evoked potentials that reflect visual information processing in brain. For the purpose, an experiment is carried out on two experimental conditions. The first condition requires subjects to watch visual stimuli that are presented to them repeatedly, and the second requires them to do auditory tasks while watching visual stimuli. Results of the experiment show that response quantity of visual information processing is diminished when auditory tasks that attract subject's attention to hearing are imposed on them, even if they see visual stimuli using their central vision.

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An Experiment on perceived air quality using sensory subjects was conducted in room A where one year passed after an interior repair work, and in room B where 25 years passed after the construction. In room A, the VOC concentration of the paint origins was slightly high. The subjects were divided into two groups, i.e., the group, who assesses perceived air quality using the questionnaire which specialized in the air quality (questionnaire II), and the other group using the questionnaire which asks thermal comfort, lighting comfort, noise perception and perceived air quality (questionnaire I). For the assessment by the group which used questionnaire I, there was no significant difference in the voted odor intensity of room A and that of room B. For the assessment by the group which used questionnaire II, the odor intensity of room A was significantly higher than that of room B. The nudge to the air quality assessment by the difference in a questionnaire might affect the perceived air quality assessment.

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