This paper discussed on human sensitivity and discomfort to floor vibrations with various duration times. Shaking table tests with vibrations of various combinations of the frequencies, amplitudes and duration times were performed. The sensitivity and the discomfort to the whole-body vibrations are evaluated by test subjects seated on the shaking table. As the results, the duration times influence to the discomfort more than the sensitivity to the vibrations. The discomfort to the vibration with the duration time of 30sec. increases about from 1.2 to 1.3 times as large as one with the duration time of 3 sec.

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The purpose of this study is to compare the perception of the brightness of light in sitting posture against reclining posture through an experiment. Three factors were controlled in the experiment : the position of light source; the luminance of the source; and the subject's gazing condition in reference to the source. The subjects were allowed to adjust the brightness of the compared light source with the brightness of the standard light source. Then, the ratio of brightness between the compared and the standard source was analyzed at each posture. The followings results were obtained : 1) The relative position in visual field which is most sensitive to brightness changes along with posture. 2) The difference among the ratio of three luminance levels is larger in sitting posture than reclining posture. 3) Peripheral visual field is perceived as being more brightly than the central visual regardless of position, luminance of light sources and subject's posture.

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The purpose of this research is to seek the relationship between lighting environments and furniture arrangements in a living dining room. In an experiment, five lighting environments were presented to subjects, and they were asked to arrange tables, chairs and a sofa freely. As a result of the experiment, it was revealed to be common for all subjects to put the dining table on the kitchen side and put the sofa in a position on the wall side away from the kitchen in the general lighting. When the room was illuminated non-uniformly and the lighting area was separated from the kitchen, some subjects tried to put the dining table in the vicinity of the lighting, and others did not change the position. For subjects who had changed the position of the dining table according to the lighting condition there, tended to be a strong relationship between eating behavior and brightness. On the other hand, subjects who did not change the position of the dining table even if the lighting condition changed tended to value the convenience of the positional relationship in the room, and tried to change behavior location to adjust to the lighting.

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There are many factors both from outdoor (For example : natural ventilation etc.) and indoor (For example : human bodies, a hot-water supply equipment, the moisture-conditioning material etc.) which contribute to the indoor humidity environment. The purpose of this study is to investigate the contribution of each factor to the indoor climate. In this study, the indoor humidity environment is treated as a linear summation of the contribution from each factor, which can cause an increase or a decrease of humidity to the indoor environment. Then new indices for assessing the contribution of each factor to humidity distribution in a room are proposed as CRI_<(H)> (Contribution Ratio of Indoor Humidity) 1, 2, 3 by means of CFD (Computational Fluid Dynamics) simulation. Moreover, the indices are employed to carry out a 3 months transient simulation in a model living room while moisture-conditioning material is arranged, and also the simulation result is compared with those of a previous uniform model and CFD model of humidity in order to confirm the effectiveness of those indices.

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In this paper, in order to clear the thermal comfort zone in wearing suits, the experiment was conducted under low-humidity conditions in the steady temperature and humidity room, assumed office in winter. As a result, it was clear that there were the sexual difference of MST, SET^*, and acceptable rate of thermal environment. And it was shown that natural TSV is represented in MST of 33.1℃ in male subjects and 33.6℃ in female subjects, and also that natural TSV is represented in SET^* of 25.6℃ in male subjects and 26.4℃ in female subjects.

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This paper reports the effect of absorptive building material in reducing formaldehyde in indoor air. Although some studies have reported that absorptive building materials are effective in reducing concentrations in small test chamber method by experiments, there are few studies which are carried out in actual room. In this study, numerical analysis on decreasing effect of pollutant concentration with absorptive building material in full-size resident model is conducted. And we examine the reduction effect of changing the surface area of the adsorptive material in a room and the most effective arrangement of material using the numerical analysis. We confirmed that the reduction effect is not always proportional to the adsorption surface area.

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Energy conservation in the building sector is now given the great attention to with the surge of consciousness for a global environment. Due to advances in technology for building facilities, many choices of building equipments are available when designing an energy system in a building or in an urban area, such as cogeneration systems, triple-effect absorption refrigerators, high efficiency air source heat pumps, etc. Although so many choices exist, it is difficult to make a quantitative evaluation and decide which energy system is best, i.e. the lowest cost or the minimum environmental impact. In this study, a new optimal design method for buildings and urban energy systems is proposed. Also its applicability is analyzed using a simple case study. Genetic Algorithms (GA) which can deal with non linear optimization problems are adopted for this optimization. This method has two optimization steps, selection of equipment capacity and selection of optimum operational planning. These optimization steps are calculated simultaneously. The results showed that the proposed method has the potential to be applied to very complex energy systems and achieve significant improvements.

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Room air conditioner is one of the home electric appliances with much electricity consumption. The performance data of a room air conditioner that published by manufacturer is measured by the method of providing in Japan Industrial Standards. The indoor and outdoor conditions of the published data are provided by the standard, too. The published performance is not necessarily demonstrated because the energy consumption characteristics of room air conditioner depend on load conditions, environmental conditions and equipment control settings. However, the performance of the room air conditioner is often assumed constant when the energy consumption of a residential building is calculated. The cause is that the energy consumption characteristics of room air conditioners at the actual environmental conditions are not clarified. This paper presents the cooling performance of a room air conditioner at the off-designed conditions as a basic data of the energy consumption calculation of a residential building.

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This paper deals with authors' elaborated air conditioning system composed of under-floor air conditioning and natural ventilation in combination and equipped with ceiling fans. This paper as Part II of the preceding one reports details of our study on desirable shape of ceiling fan and lighting fixtures integrated unit in place. Also introduced are results of experiments, field measurements and simulation about load reduction on the air conditioning system the authors conducted to confirm effects of the ceiling fans, especially actual indoor air distribution tendency, air conditioning load reduction effect, and comfortableness office workers feel when air conditioned with ceiling fans sending a little air to them.

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Using the feature of the thermal conductivity of copper, the authors developed the void pipe floor heating system. Indoor experiments verified that the system has the same heating performance as the general heating ones. In this paper, the data from the experimental house equipped with our newly developed system and the data from indoor experiments on the same system were compared. Also, by using the simplified floor panel model we computed the heating performance of the systems in the experimental houses with different insulation capacities. The data from the experimental house showed that the system in the steady state can keep the floor surface temperature at about 31℃ and indoor temperature at about 25℃. However, although the system has an improved heating performance, it still takes about 8-10 hours to reach the steady state even in case that the house has high insulation capacity.

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In this research, the operation realities of the heat load characteristic, the equipment composition, the capacity division, the operating number control, and the equipment efficiency etc. of the District Heating and Cooling (DHC) Plants in 54 places in central Tokyo area were understood, and the operating actual conditions of the DHC plant were clarified. It doesn't depend on the heat source method, and the difference is seen by system COP in the difference of the heat load characteristic and the plant operating condition. The operating rate is 50% or less a year, and the operating time by 20% or less exceeds half a year. The heat loss of the year is 22% on the average of heating heat, and 6% on the average of cooling heat. For improving the system COP, the plant makes an effort to dividing the capacity, controlling the operating number etc. of the heat source equipment according to the heat load characteristic in the region. It is hoped that the existing DHC plants improve a further energy conservation performance by load leveling and the expansion of heat demand.

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Recycling rate of mixture wastes mainly come from dismantled interior material of buildings stays low. To promote the classification of dismantling from interior part, it is necessary not only separation interior parts from skeleton of buildings but also separation between various interior parts itself such as groundwork boards and the finish crosses. In this study, 'the rates of separated waste from the mixture' is defined. The dismantling or reform spots are investigated and dismantling easiness of interior material is analyzed. The execution spot of advanced specifications are also investigated and pointed out problems in the future. In addition, to promote recycling, the interior to be easy to dismantle is proposed and examined the effectiveness by a dismantling experiment.

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Four kinds of actual-size exterior walls with exterior vented air-layer were installed in a hot box with solar simulator. Although solar reflectance of the outside surface and surface emissivity of the vented air-layer of the four walls were different, the other specifications were identical. Under the given room and exterior temperatures and solar radiation conditions, wall surface temperatures as well as wall inside temperatures and heat flow were measured, changing openings of the vented air-layer set close or open. Based on the measurements, thermal performance of the four walls was compared. Comparison was also made between the measurements and calculations by the method proposed in the previous paper. The result shows that the values obtained by the calculation well represent those by the measurement.

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The reuse system mentioned in this paper is an overall system for realizing a reuse business in a series of cyclic process in a reuse flow, namely, design, fabrication, construction, maintenance, demolition, and storage. Here, we propose structural performance evaluation method for reusable members, taking up rolled H-section steels. Authors fabricate structural members obtained by a conventional demolition or reuse demolition, and do fundamental and partial frame tests of beam to column connections, and evaluate fabrication and structural performance of reusable members of building steel structures.

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