The noise inside an automobile exerts various influences on the driver. In this context, the concept of active noise control (ANC), which reduces the noise in the automobile, has been reported. Subjective evaluation has furnished empirical evidence regarding the effects of ANC. However, few studies have investigated the effects of ANC using a physiological evaluation. Therefore, we studied the effects of ANC on the physiological functions using recorded driving noise with ANC ON and OFF conditions. Ten male subjects participated in this study. They completed four consecutive sessions: a 20 min quiet period as baseline, a 10 min noise exposure with ANC ON or OFF, a 60 min mental task period during noise exposure with ANC ON or OFF, and a 20 min recovery period. We measured electrocardiogram, photoplethysmogram, electroencephalogram, blood pressure (BP), baroreflex sensitivity and internal secretion indexes such as cortisol. Before and after the task, the subjects were evaluated on the Kansei-gakuin Sleepiness Scale, and after the task, they answered the NASA-TLX. Two experiments with ANC ON and OFF conditions were conducted at the same time of day on separate days. Data of the ANC ON condition and ANC OFF condition were compared by the paired t-test. We found that systolic BP, diastolic BP and sympathetic nerve activity during the ANC ON condition were significantly lower than those during the ANC OFF condition. Furthermore, parasympathetic nerve activity during the ANC ON condition was significantly higher than that during the ANC OFF condition. The results suggested that ANC effectively reduces the stress level in physiological functions, especially the cardiovascular system.

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We report the time-of-day-dependent effects of monochromatic lights at wavelength of 458 nm and 550 nm on human physiological and psychological parameters under the same irradiance density (9.8 µW/cm² at eye level). We conducted an experiment in the daytime and nighttime on different days. Twelve subjects were selected, none of whom was either a morning-type or evening-type person, as assessed by the morningness/eveningness questionnaire. We found that 458 nm light exposure caused a greater high-frequency (HF)/(HF+low-frequency (LF)) component than did 550 nm light. The change of oral temperature (ΔTor) during exposure to 458 nm light was larger than that to 550 nm light in the daytime. Our findings indicate that short-wavelength monochromatic light can affect the circadian rhythms of autonomic nerve function and body temperature.

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This study examined the influence of wearing trousers or shorts under firefighting protective clothing with phase change materials (PCMs) on physiological/subjective responses and the mobility of firefighters.
Experiment 1: Eight Fukuoka City firefighters (28±3.6 yrs) participated in the research and rested in a pre-test room for 10 min before entering the test-room where they rested for another 10 min, followed by a 30 min-exercise period (on a treadmill, 4.8 km·h⁻¹ at a 3% gradient) and a 10 min-recovery period. Rectal temperature, mean skin temperature, heart rate, body weight loss and subjective responses were measured.
Experiment 2: Eight Fukuoka City firefighters (27.9±3.5 yrs) participated in a freedom of movement test, an exercise test and answered a set of questionnaires. The exercise test involved obstacle courses with 70 cm and 90 cm obstacles.
The results suggest that performance was improved while wearing shorts under protective clothing with PCMs, although no significant difference in reducing thermal stress while wearing shorts instead of trousers was revealed.

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We intended to clarify the present states of special old age nursing homes and elderly health care facilities in Japan especially in a cold climate region. A questionnaire survey about maintenance and control of living environment for all special old age nursing homes and elderly health care facilities in Sapporo and Fukuoka City, and Hokkaido, Saitama, Kanagawa, Osaka Prefecture and Tokyo Metropolis was performed. The main questionnaire asks about heating, air-cooling, ventilation system, sanitary system and indoor air quality including bio-aerosol and odors. We send the questionnaire sheets, which were A-4 size and four pages, to total 1,479 homes and facilities. We received total 646 answers, about 44% of total number. The 95 questionnaire items were converted 249 categories for statistical analyses.
The present database for special old age nursing homes and elderly health care facilities consists of about 160,000 data. The data obtained from Sapporo City and Hokkaido Prefecture were compared with those of other regions. We show the characteristics of special old age nursing homes and elderly health care facilities in a cold climate region in this paper. The main differences were set values of air temperature in both winter and mid-summer, and air-cooling system.

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