In this research, the outdoor thermal environment around residential buildings with and without greens were measured in winter and summer, and the following results were obtained. 1) In summer and winter, outdoor air temperature is 1.5K lower in the green space than in the no green space. 2) In summer, ground surface temperature is 8.3K lower in the green space than in the no green space. 3) In summer, moisture ratio is 1.1g/kg' lower in the green space than in the no green space. The results show that greens are effective to moderate air temperature, ground surface temperature and humidity. Heat mitigation effect of trees extends to out of tree shade. According to this measurement, the optimal green plantation is about 4.5m in height and 4m away from the building.

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Residential buildings with high insulation and airtightness have been successfully diffused in cold regions to reduce energy consumption. More recently highly insulated, airtight houses have also been built in hot, humid regions in order to reduce air-conditioning and heating energy. However, concerns have been raised that highly insulated, airtight construction may cause moisture problems such as condensation, mold and decay inside of the walls and crawlspace in these regions. This paper reports the results of the measurement on a highly insulated, airtight house in a hot, humid region. The measurement data was used to verify the accuracy of the computer model. The simulation results confirmed the performance and advantages of highly insulated, airtight buildings.

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In this paper we examine accuracy and speed of calculating view factors about several geometries using Monte Carlo method, Hemi-cube method, double area integral method and Mitalas-Stephenson method. As a result, the following conclusions are revealed : If there is no obstruct in geometry, Mitalas-Stephenson method has overwhelmingly good performance than other method. Although Hemi-cube method is not good at calculating view factors with very high accuracy, it is faster than Monte Carlo method as far as ordinay precision is required. Monte Carlo method is slower than other method, but it is easy and safe to calculate view factors with high precision using this method.

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We investigated the actual status of the thermal environment and heating methods in the main bedroom and the space around the living room in 15 prefabricated houses built in the Kansai area with approximately 25% higher insulation capacity than the new energy-saving standard. The results are summarized as follows : 1) All of the residences surveyed have a heating apparatus in the main bedroom. But residents use them for a very short time because they seldom use the main bedroom for any purpose other than to sleep. 2) The temperature of the corridor is low the whole day, because that is a non-heated space. The difference in temperature between the corridor and the LDK is about 5-15℃ in the evening. 3) Residents with the intention of trying to extend the heating space to the room adjoining the LDK, the corridor and so forth were not observed.

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Subjective experiments were conducted both in summer and winter in order to clarify the effects of humidity environment and indoor chemical pollutants on subjective comfort and productivity, and evaluate the seasonal difference of their reactions. Subjects were exposed to the three levels of humidity conditions and two indoor air quality levels performing the simulated office works. Concentration of formaldehyde was lower in low humidity environment. The effects of environmental humidity and indoor air quality on subjective thermal comfort were moderate under thermally neutral conditions in both seasons. Perceived air quality was affected by indoor air quality under the polluted condition and by humidity environment under the clean condition. Irritations of mucous were found under polluted conditions in winter though they were not found in summer. Environmental humidity had larger effects on skin moisture than indoor air quality. Subjective performance was higher under clean condition than polluted condition with same humidity. Subjective performance was higher and their dificulty of concentration was lower under high humidity than that under low humidity in winter. The seasonal differences of eye dryness, BUT and skin moisture were found.

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In this paper are discussed the thermal performance of a solar house which has air-type solar heating system and Water Floor. The Water Floor is composed of wooden floor and water bags in the floor framing and is used for heat storage and floor heating, and also to decrease the temperature difference in the house. The thermal performance of this house and the effect of Water Floor on the indoor climate control is discussed using the long-term monitoring data in winter. The results show that Water Floor has good performance both of heat storage and heat distribution and the indoor environment is kept in comfortable level.

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In January 2003, JIS A1901 on "Determination of the emission of volatile organic compounds and aldehydes for building products -Small chamber method" was published. We have proposed and developed a small chamber for determining chemical emission rates from building materials. In this paper, the performance characteristics of small chamber were examined especially background concentration, airtightness and mass transfer coefficient in the chamber. The performance test method was proposed because that was not clearly stated in related standards. The measurement method for mass transfer coefficient by used the filter paper is applicable for the calibration with the measurement for evaporation-controlled materials. Several small chambers have been used to determine chemical emissions for building materials. However, it is difficult to compare with the result from different chambers. In this paper, formaldehyde concentration with two small chambers was discussed by the relation with loading factor (L) and ventilation rate (n). It was observed that it has possibility to compare with the linear of n/L versus 1/C with used the equilibrium concentration for the segment.

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This paper aims to establish the performance testing method for domestic air cleaners to remove single gaseous chemical substance. At first, 4 experiments were performed with gaseous formaldehyde(HCHO) on 5 air cleaners : (1) filtration test by concentration-decay, (2) re-circulating test by concentration-decay, (3) filtration test by constant-emission, and (4) re-circulating test by constant-emission. These results suggest that type-(3) as same as a penetration test for gas-removal filters is appropriate and removal efficiency(η) as same as arrestance of filters obtained from this test is the best index to evaluate the performance. Further experiments with gaseous toluene and xylene were conducted. This testing method and index can apply to all air cleaners in spite of its mechanism.

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The loads of cold and hot water consumption are changing by progress of water supply systems and spread of the water-saving fixtures aiming for energy saving in the various buildings. 0n the other hand, people's life style has also been changing by various factors, for example, social, economical, cultural factors and so on. Under these situations, it is necessary to adapt the calculating method to the changing loads for the design and maintenance of buildings. The authors have advanced the development of calculating method based on the data of water consumption for daily, hourly and instantaneous loads in the time series through a day by using a personal computer. In this paper, we carried out the questionnaire investigation about the household's behaviors using hot water and the measurement of cold and hot water consumption per month and per hour in the apartment houses located in Sanin and Sanyo areas. The survey areas were supplied the different cold water temperature because of the separate two sources such as the river water and ground water. Using these data measured fol one year, this study aims at getting various basic data adapted the calculating method for the loads of water and the supply syste's capacity and developing the relationship between the cold water temperature and the usage ratio of cold and hot water demands.

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We experimented on eggshell wastewater in drainage system with food waste grinder for business use, in oder to improve the transport performance by the intermittent operation of positive displacement pump. First, operationg the pump after storage water by stopping the pump, made eggshell flow by moving bed. Compared to the continuous operation, eggshell remains in pipe were 20-40% weight by the intermmitent operation also in the same amount of water supply. Two fomulas on the maximum stop times and the equivarent volumetric flux of liquid phase, were drawn. Furthermore, remains presumption fomula which also added pipe length influence were drawn.

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Fifteen subjects performed sedentary work in the room under three different levels of air temperatures and four different conditions of indoor air quality. Among the three levels of air temperatures, the subjects assessed the thermally neutral room, where air temperature was 26.5-27.5℃, as very acceptable. However, the highest performance was obtained under the condition with air temperature of 22-24 ℃, where thermal sensation was expected to be cool or cold. Based on the evaluation trend for pine scent, the subjects were divided into two groups : 1) group A, who assessed the pine scent not acceptable at higher odor intensity level, and 2) group B, who accepted the pine scent even at the high odor intensity level. The conditions with the scent had better influence on the self-reported arousal and performance for the subjects of Group B, while the conditions did not have better influence on them for the subjects of Group A.

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The effects of air movement from the floor to the ceiling on the human physiological and psychological responses were examined by the subjective experiments. In this study three male students were exposed to the combined eight conditions of air temperature (24℃ and 28℃) and air velocity (0.3m/s, 0.5m/s and 0.7m/s) under humidity 60%RH. To evaluate the effect of air movement on local position of the body, the corrected humid operative temperature HOTV was applied to the local position. There were high correlation between HOTV and the skin temperature on both of local positions and the whole body. The effect of air velocity could be represented by use of the air velocity effect index based on the thermal velocity field.

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The objective of this study is to clarify the key points for better recycling of the concrete waste from building demolition, based on surveys in the fields of waste disposal and building demolition. The results showed that the impurities contained in concrete waste form major obstacle to better recycling, even causing increased C0_2 emission. The removal of them should be considered in the previous stages to waste disposal. It was suggested that further efforts should be made for easier removal of plastics, glass. copper (electric wire, piping etc.) and ceramics in demolition process and of plastics and copper in designing process ; and in view of components, for easier removal of finishing materials and various fixtures in demolition process and of the fixtures in designing process.

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