Twelve young woman subjects rested or exercised in the outdoor environment in the summer season. Rectal temperature, skin temperatures for chest, back, upper-arm, thigh, and leg, and heart rate were continuously measured and thermal and comfort sensations were recorded. Before and after the experiment session the body mass was measured and the mass loss was calculated for the period of rest or exercise. Moreover, air temperature, humidity, air velocity, globe temperature and horizontal solar radiation were measured and, SET^* and WBGT were calculated. The physiological, psychological and environmental results were compared for 4 conditions; solar radiation on the front surface from sun, on the back surface, in the cloudy, or in the shade. Effects of solar radiation were found in the thermal sensation and radiative heat sensation, however, not found in other psychological sensations. Skin temperatures for thigh and leg were influenced by the solar radiation and the MST (mean skin temperature), mass loss and skin wettedness were higher under sunshine than under shade and cloudy.

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The device which gave the cold stimulation to the region of the human body was made. On the 16 regions of 45 young male subjects, the skin temperature and the heat flux were measured when the cold stimulation was given. The cold sensation thresholds were calculated from the skin temperature, the heat flux and the amount of heat. As a result, the influence of the difference of summer experiment and winter experiment on the cold sensation thresholds was not shown. But the influence of the difference of the temperature change speed condition on the cold sensation thresholds was shown. Therefore, the cold sensitivities were calculated from the standardized cold sensation thresholds. It was clear that the cold sensitivities of young male subjects were similar to the cold sensitivities of young female subjects. It was clear that the cold sensitivity of the upper abdomen, the abdomen and the neck were high, and the cold sensitivity of the back of thigh and the leg were low.

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The wearing of sunglasses with UV-filtering lenses to protect our eyes from ultraviolet radiation is recommended. This study was conducted to examine the relationship between the color of sunglass lenses and color discrimination. We performed the 100 Hue Test involving young females to examine their ability to discriminate colors. The illumination intensity was set to approximately 5,000lx, and three colors of lenses were used in the test. We compared deviation values between subjects wearing smoke color, blue, brown, and no sunglasses, and no significant difference was observed. Then we compared mean deviations for each of 100 hues on comparison of the brown and no sunglass groups, significant differences were identified for nine hues. Particularly in the purple blue (PB) field, the mean deviation was lower in the brown group, which indicates that sunglasses with brown lenses are more effective in discriminating purple and blue colors. No marked difference was noted in deviations between the red purple (RP) and blue green (BG) fields, and deviations in the brown group were significantly greater in both (RP and BG) cases, which is in line with the results of previous studies of deviations in the elderly.

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This paper proposes environmental energy diagnosis for detached houses in the cold region and shows the diagnosed cases of monitored houses using efficient energy equipments for the purpose of energy saving in the residential sector. We adopted a polymer electrolyte fuel cell, a CO_2 heat pump water heater, a ground source heat pump, and a photovoltaic power generation as efficient energy equipments. First, we implemented performance evaluation on each of the efficient energy equipments and actual field measurements at monitored houses. Second, the coefficient of primary energy consumption (CPEC) was proposed as an index for the energy conservation. As a result, the excellent performance of the fuel cell was shown at the present stage. Finally, we carried out analyses on the lifestyle of monitored houses and the performance of lights and appliances. Relatively low cost for the energy conservation strategies and improving measures of the environmental consciousness promise reduction of primary energy, and most evaluation indices become superior compared with standard values.

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This study examined the effect of thermal environment on water turnover (WT) in 86 Japanese children aged 4 to 6 years. We compared WT between 32 children on summer day and 54 on winter day. WT was measured in spring in Miyazaki and from the end of fall to the beginning of winter in Akita prefecture, respectively. Deuterium oxide (99.9%) was administered and the elimination rate (kh) over 6 days was calculated. WT, expressed as a percentage of total body water (%TBW), was calculated as a product of kd and 100. WT (%TBW) was 17% higher on a summer day than on a winter day. This result suggests that thermal environment is among factors which contribute to the individual differences in WT in children.

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This study was conducted to examine the use of computers among university students, their sense of physical fatigue, and problems arising from watching the screen, as well as discuss the relationship between their fatigue and screen-related problems. The following results were obtained: Information technology-related and male students spent more time per day on average using computers than those in other departments and females. As many as 92.6% of the subjects stated that they felt tired while using computers. The most common symptoms included "eye soreness", "eye fatigue" and "stiff shoulders". In students of other departments, a relationship was noted between these symptoms and the time spent using computers. The screen interface, colors of characters and backgrounds, and other screen-related factors were also associated with their sense of physical fatigue. In developing educational materials and contents for computer learning, it is important to enhance screen usability to help students achieve desired learning effects while preventing eye fatigue as much as possible.

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In order to assess thermoregulation disorders of children with severe multiple disabilities, a questionnaire survey was conducted of 206 severely disabled children enrolled at all 5 schools for disabled children in Yokohama City, Kanagawa Prefecture (valid responses, 182). The main findings were as follows. 1) Among the 182 children, 67 (36.9%) had some form of problem with body temperature condition (heat retention, hypothermia, both). 2) Among the 46 lower grade elementary school children, 24 (52.2%) had some problems with body temperature condition, a significantly higher proportion than that of other grades. 3) The principle causes of heat retention and hypothermia might be excessive thermogenesis due to intense muscle tension and reduced thermogenesis due to disuse atrophy of skeletal muscle, respectively. 4) 64.3% of the students with both heat retention and hypothermia (9 out of 14) were lower grade elementary school children. Young children might be more easily influenced by the thermal environment because of reduced heat dissipation due to dyshidrosis and reduced thermogenesis due to lethargic movement or low nutrition.

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