The purpose of this study is to show the peculiarity of mood and impression evaluation in the VR system for the simulation of a residential environment using a large screen. We conducted a psychological evaluation for a virtual space and real room using the SD method and found that the VR space brought a pleasant mood, but the first experience of a virtual space caused a nervous condition. Moreover, it was difficult for them to acquire a fresh feeling as well as a sense of width and depth in a virtual space, in contrast to a real space. Furthermore, it was easier to express beauty, simplicity and youthfulness, but more difficult to express warmth and individuality in a virtual space.

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The purpose of this study is to reconsider the optimal lighting conditions in office buildings with respect to both the occupants' visual comfort and reduced energy use. This paper reports on how the lighting in office buildings in Japan changed after the events that followed the Great East Japan Earthquake in March 2011. For the first step, a survey of facility managers in office buildings was conducted nationwide. The survey focused on specific measures taken to reduce power consumption. Additionally, the occupants of each office building filled out a questionnaire about the lighting conditions in their working areas.
The results showed that for about half or more buildings, saving measures for lighting and air-conditioning during the summer months were taken. With regards to lighting, the number of illuminated lamps was reduced (partial lighting) and ceiling luminaires were turned off automatically at a preset time in order to avoid forgetting to turn them off when unnecessary, such as lunch-time or at the end of working hours. It could be supposed that the desktop illuminance of the most of the office buildings shifted from 750-1000 lx to 300-500 lx due to electricity-saving measures.

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When the thermal performance of a building is evaluated, a common method is to handle window frames and building walls as independent parts respectively, and successively to summate the thermal performance of each part through putting weight on the area. This method presumes that there is no heat transfer between the parts neighboring with each other. However, in a real building, heat transfer exists at the parts connecting window frames and building walls.
In this report, heat transfer was calculated through numerical method on several typical combinations between window frames and building walls, and the effects of the obtained values on the thermal performance of a building were confirmed. As a result, it was confirmed that heat flow was not small between a window wall and a building frame at the window frame structure made of aluminum or aluminum-plastic composite, which increased the heat loss of a building by about 5% at a maximum.

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Semi-volatile organic compounds (SVOC) are contained in building materials including plasticizers and flame retardants, and adverse effects for the human body have been are concerned. It is important to understand of SVOC behavior to reduce exposure risk. The principal aim of this study was to clarify the emission mechanism of DEHP from building materials which is a kind of SVOC. First for some PVC floor tile, emission rates by three methods (FLEC, CLIMPAQ, Little's chamber) and by Micro chamber method were compared. Second experiment was investigated DEHP emission rates from cushion floor under varying air flow volume using micro chamber. In addition, the airflow characteristic of micro chamber was investigated using computational fluid dynamics. Micro chamber method can measure SVOC emission faster than other methods. DEHP emission rate is subject to the airflow velocity near the building-materials surface, the thickness of fluid film under steady state condition.

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In the design of a ceiling radiant cooling and heating system, it is important to calculate the indoor thermal radiant environment and heat performance of a ceiling radiant panel. From the results of heat performance experiment, we clarified the radiative and convective heat transfer coefficient of a ceiling panel . And we developed the heat exchange equation model of a ceiling radiant panel using fin efficiency. The calculated values of the heat quantity using this model give close agreement with the actual measured values. Therefore, this model can be used to design ceiling radiant panels.

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This research divided granular water retentive building material into its material part and void part, and proposed a method of integrating both parts based on heat and moisture transfer formulae for each part. Next, granular water retentive building materials were installed outdoors on 5m by 5m square horizontal scales, and its surface temperature, water retention, etc. were observed. The results revealed that the surface temperature of granular water retentive building materials falls by 20°C more during the day and by 5°C more during the night than the surface temperature of ordinary asphalt covering. And simultaneous heat and moisture transfer of granular water retentive building material were analyzed based on a development model, confirming that its surface temperature and water retention behavior conform closely to the results of observations.

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In this study we aimed to identify characteristics of energy consumption of accommodation building by drawing on 2009 fiscal year of DECC survey data. Conducting statistical analysis on the base-load and the fluctuation-load on a national scale derived from patterns of variation in the monthly energy consumption, we obtained estimation equations for energy consumption rate.
To determine the base-load rate, we focused on differences between heat-generation equipments in the accommodation buildings and classified them into three categories: electrical, fuel-based, and electric-fuel hybrid. We then carried out the multiple regression analysis for each category. As a result, we obtained accurate estimation equations for the electrical and the fuel-based heat-generation equipments. And to determine the summer and the winter fluctuation-load rate, we were able to obtain accurate estimation equations using the multiple regression analysis.

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The purpose of this paper is to consider the living environment for health promotion focusing on chronic pain such as the low back pain and shoulder stiffness, that many Japanese people suffer from. The questionnaire survey was conducted with 5000 adult women with a history of pain. Exploratory factor analysis revealed that living environment, activity of daily life including housework and chronic pain consisted of 27 items and five factors: "Chronic Pain", "Stress and Fatigue", "Total Hours of Housework", "Enjoying Housework" and "Satisfaction of Living Environment".
Covariance structural analysis revealed the following thing. (1) Four subscales accounted for 73% of the "Chronic Pain." (2) "Stress and Fatigue" have affected "Chronic Pain" greatly. (3) "Enjoying Housework" and "Satisfaction of Living Environment" affected directly on "Chronic Pain" slightly. (4) However, more than it, "Enjoying Housework" and "Satisfaction of Living Environment" affected on "Stress and Fatigue" greatly. As a result, "Chronic Pain" is improved greatly indirectly.

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A comprehensive, nationwide assessment of whole municipalities in Japan was conducted using the Comprehensive Assessment System for Built Environment Efficiency (CASBEE) tool specifically designed for city level assessment (CASBEE-City). As with other tools in the CASBEE family, CASBEE-City is also based on the concept of environmental efficiency and calculates the value for built environment efficiency (BEE). In this study, BEE is calculated by using public statistical information and visually displayed on a map through a geographic information system (GIS) to understand the current situation of all municipalities in Japan under the same assessment criteria (same assessment items, thresholds and rating functions).

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We calculated the difference between the amount of fixed carbon and the carbon emissions in order to calculate the carbon balance of local wood used in the construction of houses. The target tree species were the Japanese cedar which grows in Northern Nagano and the Japanese larch which grows in Eastern Nagano. We researched and calculated the percentage of wood that was wasted in the forest and the lumber mill. We measured the energy used at these two locations and at the log market. We also calculated the CO₂ emission from energy consumption at these three locations, and during the transportation of the wood. In addition, we researched the volume of by-products from the lumber mill, according to their application. The following results were obtained. The Carbon Balance of the Japanese cedar was 475kg-CO₂/m³, the Japanese larch (using biomass for artificial drying) was 728 kg-CO₂/m³, the Japanese larch (using fossil fuel for artificial drying) was 788 kg-CO₂/m³, respectively.

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The purpose of this study was to develop a prediction tool for designing and building houses with low volatile organic compounds (VOCs) to prevent people diagnose sick building syndrome. First, 116 VOCs were analyzed in detail from 124 indoor air samples collected at 29 rooms in 8 houses for over 5 years. Next, multivariate analysis was conducted to find the influencing factors and contribution on the VOC emission. As the results, it became clear that flooring materials, construction method and time after finishing construction were the major factors. Finally, a prediction tool of VOC level in indoor air was designed.

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Choice of water heaters in the housings built in 2010 across Japan is analyzed using multinomial choice models, with a focus on custom-made single-family housings. It was found that the most influential parameter is the resident's perceived importance towards water heaters, generating higher preference to energy-efficient, and in particular electric, water heaters. As such, the perceived importance greatly influences the macroscopic substitution within the water heater market, in particular that of the energy-efficient electric water heaters.

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