The aim of this study was to examine the effectiveness of a mobile radiant cooling panel coated with natural nephrite to improve radiation efficiency. First, radiant capability such as radiant temperature, panel surface temperature, and flowing water temperature were measured in the old type of radiant cooling panel (O panel) and radiant cooling panel coated with natural nephrite (N panel). The N panel showed a distribution of the lower radiant temperature compared with the O panel and improved energy conservation. Next, eight healthy male students participated in the experiment to assess the differences of thermal comfort and thermal sensation between an N panel and an air conditioner. They felt thermal comfort even in a warm thermal state rather than the neutral thermal sensation in N panel, and thermal comfort tolerance was larger in N panel than in air conditioning.

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In order to make clear energy consumption of the elderly couple households and the effect of energy-saving lifestyle on energy consumption, measurement of energy consumption and indoor thermal environment of two elderly couple households throughout a year and experiments on lifestyle changes for energy conservation were carried out. In the experiment, energy-saving lifestyle plans was indicated to each occupant, and a questionnaire survey was conducted regarding the frequency of action for implementing energy-saving measures in winter, spring and summer. The consequent energy savings of these lifestyle changes were analyzed. The results were as follows. (1) Total energy consumptions for the two elderly couple households were 45GJ/year and 20% less than those in a reference, because the occupants usually follow an energy-saving lifestyle. However, it can be generally said that the quality of the indoor thermal environment for the elderly couple households is not necessarily good. (2) The energy consumption during the energy-saving week decreased 13%, 7% for each house in winter in comparison with the week before adopting an energy-saving lifestyle. (3) Effective plans on lifestyle changes for energy conservation in the two surveyed households were shown from the experiments.

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The objective of this paper is to clarify secular change and distribution of Discomfort Index DI during summer in Japan. Mean values of the calculated DI using AMeDAS data for every 10 years from 1961 were analyzed. As for the best DI maximum, Hokkaido compare 1960's and the other generations on a day, and all generations are high. As it is 2000's from 1960's so as to go south than this, the tendency that the generation when the best DI maximum throws it on a rise from a fall on a day becomes late is seen. As for the minimum DI maximum, the minimum DI maximum rises to Hokkaido, Tohoku region by a rise of the temperature on a day from 1960's to 1980's on a day. In the other areas, 1980's had many drops until 1990's in 1970's. However, minimum DI maximum is low, and the other areas tend to rise on Hokkaido, a day of Tohoku region in 2000's. Changes of monthly maximum difference between daily maximum DI and daily minimum DI in each city were calculated and compared. Japanese land was classified into 6 area based on that calculated change condition and its related distribution map was illustrated.

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Lighting has a vital impact and is indispensable in making the formative expression of the walls in a commercial space apparent. Using current technologies that often incorporate incandescent bulbs, however, would invariably lead to increased energy consumption with an attendant impact on the thermal load in the interior environment as well. Built-in lighting installed on the walls and ceiling in a commercial space is an important approach. So in order to employ LED lighting, we incorporated lenses in the built-in lighting devices, thereby condensing the light, enabling a dramatic distribution of LED light, raising efficiency with low wattage. In this way, the number of LED devices can be reduced, and waste can be eliminated. In this study, LED lighting was employed as the light source in the areas of built-in lighting, which allowed us to create dramatic lighting of wall surfaces and the like, as well as to achieve lighting design with even greater energy efficiency.

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The subjects were 20 young women (21.3±0.6 year old) and divided into two groups, an HS group (being sensitive to the heat, n=12) and an NS group (being non-sensitive to the heat, n=8) due to self-judged. Skin temperatures at 7 sites, oral temperature, humidity between skin and clothes, thermal sensation and thermal comfort were measured during the experiments. The three test sessions were conducted for each subject: 60-min exposure at 28℃, 30℃, 32℃ (50±10%RH) after 20-min baseline at 26±1℃ (60±10%RH). The mean skin temperatures after 60-min exposure at 28℃were 33.6℃ for the HS group and 33.2℃ for the NS group, which differed significantly between the groups (P<0.01). The HS group tended to produce more sweat and sweat earlier than the NS group, but showing no significant differences. There were significant correlations between mean skin temperatures and comfort sensation in both groups. The regression coefficient of the HS group's regression line was bigger than that of the NS group's. The HS group tended to complain of thermal discomfort with increase in skin temperatures compared with the NS group.

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A questionnaire survey was conducted on bathing habits of the elderly in winter to compare the characteristics of four districts, Sapporo, Akita, Osaka and Fukuoka, and to investigate factors associated with regional differences in bathing death rates. Subjects were asked their medical histories and living conditions in addition to bathing habits. More than half of those surveyed in this study were receiving treatment for diseases, particularly hypertension in all districts. The elderly people in Osaka and Fukuoka tended to feel colder in the bathroom in winter than those in Sapporo. As for heating equipment, a stove was most commonly used in the dressing room, and a heater-dryer was exclusively used in the bathroom. Those who have not installed heaters in their bathrooms do not feel the need for heating equipment. A logistic regression analysis revealed that the elderly in Sapporo, a district with a low bathing death rate, have a tendency to bathe less frequently, stay in the bathroom and soak in the bathtub for a short time, and feel little cold during bathing. If similar bathing habits can be formed elsewhere, they could prove useful in preventing fatal bathing accidents.

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