This study was performed to investigate the concentrations of ethylbenzene, styrene, toluene, and total xylenes in indoor air and their changes in three newly built houses. Air was trapped with TENAX tubes and analyzed quantitatively by GC/FID using the absolute calibration method. In these houses, the concentrations of target compounds were below the guidelines of the Ministry of Health, Labor, and Welfare. The differences among the houses were influenced by the patterns, but not by the types of compounds. In this study, a mechanical ventilation system reduced concentrations of volatile organic compounds in indoor air by 10% to 40%.

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The purpose of this study is to establish a simple evaluation method of seasonal load by taking in outdoor air. So, this repot shows the simple method of estimating heat load by infiltration draft and natural ventilation on office building. Expanded Degree Day was used to calculate building's heat load. The method was studied by re-expanding it. Adding seasonal infiltration draft's air volume to overall heat transfer coefficient makes it possible to establish the influence of infiltration draft. Following steps make it possible to establish the influence of natural ventilation controlled flow rate. Step 1 Calculate overall heat coefficient per floor area from reference temperature. Step 2 Estimate effective opening per floor area of the vents. Step 3 Compare cooling load and outdoor air load of non-controlled natural ventilation, and judge smaller one as outdoor air load of controlled natural ventilation. Step 4 Sum up these results of cooling period. When compared cooling load by using this method to it by using real building's variables, relative errors were less than 20%. Therefore it is acceptable to use this simple evaluation method for practice. If above results are collected each area, direction, reference temperature and the ratio of solar transmittance to overall heat coefficient in advance, it makes possible to estimate seasonal load simply including effects of infiltration draft and natural ventilation.

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This paper discusses the thermal performance of a double-skin facade in an office building located in Tokyo. Field measurements were taken in order to evaluate the performance of the double-skin facade during the summer and winter. The results of the measurements show that the double-skin facade provides inner glass surface temperatures similar to room air temperatures and good performance in terms of both the radiative thermal environment near windows and cold draughts in the winter. This high performance is due to the high thermal insulation of the inner Low-E double glazing and openings of the outer skin that are large enough to extract heat absorbed by the blind in the double-skin facade. Detailed analyses were made concerning temperature differences between the inside of double-skin facade and inlet air velocity or ventilation rate of the double-skin facade. It is also proved that there are strong correlations between temperature differences in the air space of the double-skin facade and vertical solar radiation. Correlations are also observed between ventilation rate in the air space of the double-skin facade and vertical solar radiation. However, there are only very small correlation between the ventilation rate and outdoor velocity. It is estimated that ventilation in the air space of the double-skin facade is mainly driven by the temperature differences between the outside and the inside of the double-skin facade.

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This paper describes optimization of a snow melting operation for the road surface by using image processing in order to realize energy conservation for the snow melting. First, a snow-presence determination method by using image data integration, the brightness detection, the density enlargement and the binary treatment was presented, and test equipments and a control software were developed. Second, through the experiments on the accuracy of the each process in the control software, it was confirmed that the mal function caused by disturbances (people, cars, etc.) and the brightness difference of images (solar illuminance, shade, lighting, etc.) can be prevented. Finally, we compared the hours of snow melting operation between the image processing system and a snowfall sensor which is one of conventional control methods for the snow melting. It can be seen that this system reduces the operating hours substantially.

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In this study, we proposed the ventilation exhaust and ground source heat pump system with the under floor heating system using Σ beam as a method to control an increase in the cost keeping high COP. This system achieved 3.5 of the COP and 4kW of heat output for 40℃ of the water supply temperature in the experimental house. The under floor heating system using Σ beam has the sufficient radiation performance to operate the heat pump. The heat recovery from the ventilation exhaust exchanger was maximum 1.2kW, so it means that the size of the ground heat exchanger can be reduced by 40% in this operation condition. In order to use in the optimization of this system, we showed the simple equations that revealed the thermal characteristic of the equipments and simple simulation method to predict the heat extraction rate from ground.

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Reliability for power supply is extremely high and stable in Japan, however, it is yet hard to avoid some momentary voltage sags or momentary service interruptions due to natural disasters including thunderbolts. So far, as a countermeasure against momentary voltage sags or momentary service interruptions on the customer side, uninterruptible power supplies have been installed for important loads. However, these systems have several problems such as high maintenance costs. Therefore, focusing on the ultra high-speed spinning flywheel, it has been constructed that the stand-by power system, which has a long service life without maintenance, using the flywheel as energy storage apparatus.

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