Manggur, which means to plane down or sharpen, is a manual process in producing copper blades of Balinese gamelan orchestra. The craftsmen of Manggur work 6 to 8 hours a day, sitting on the floor with folded legs and hunched back. Because the craftsmen often complain about musculoskeletal problems after having completed a full day work, an ergonom-ic intervention was made by changing their usual working posture (the first working posture) into working on tables while sitting on chairs for one hour and alternately standing for half an hour (the second working posture). Treatment by subject design was applied to 22 randomly chosen craftsmen. Resting heart rate and working heart rate were measured by using a stopwatch, and the number of musculoskeletal complaints were recorded with Nordic Body Map Questionnaire. As a result, the second working posture caused significant reductions in working heart rate, work pulse (the difference between working heart rate and resting heart rate) and the number of musculoskeletal complaints. These results suggest that the change of working posture in manggur decreases cardiovascular load and musculoskeletal strain among Balinese gamelan craftsmen.

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It has been shown that vibration level, feed force, and exposure duration cause unfavourable effects on the work performance when hand-held vibrating tools are used by operators. Present study analyzed the effects of these variables on the heart rate and blood pressure of the operators carrying out the drilling task. Under three different levels of vibration (0.3, 0.5, and 1m/s²), the operators performed the drilling for 3 minutes with three different levels of feed force (100, 200, and 300 N) in study 1, and for three different durations (10, 15, and 20 min) with a feed force of 200 N in study 2. Thirty male subjects participated in the two studies and data were analyzed on the basis of two factor repeated measure kind of experimental design. Results showed that in the kind of drilling task undertaken the level of vibration was statistically significant. However, the main effects of feed force and vibration exposure duration were statistically insignificant. These findings are discussed in the light of previous researches conducted on the subject.

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The comprehension of safety signs for construction workers was compared among existing and improved designs. Safety signs considered were existing signs, existing signs improved by adding text, existing signs improved by adding/changing pictorials, and existing signs improved by adding/changing pictorials and text. Three hundred and eighty-four construction workers were randomized for assignments into four groups. They were working on nine constructions work sites randomly selected from work sites located in Bangkok, Thailand. The number of workers in each work site was calculated for the proportion of the sample size and then they were randomized so that equal numbers of workers were included in the four groups. The four types of safety signs and an interview form were used to test their comprehension of safety signs. For data analysis, percentages, means, standard deviations, the chi-square test, the one-way ANOVA and LSD tests were applied. The results showed that the mean comprehension scores of the existing signs improved by adding text, the existing signs improved by adding/changing pictorials, and the existing signs improved by adding/changing pictorials and text were significantly higher than those of the existing signs. In addition, the mean comprehension scores of the existing signs improved by adding text and the existing signs improved by adding/changing pictorials and text were significantly higher than those of the existing signs improved by adding/changing pictorials. The highest mean comprehension score of safety signs for the construction workers was found in the existing signs improved by adding/changing pictorials and text. These results indicated that for construction workers, the comprehension of safety signs with pictorials and explanatory text was better than that of the existing signs.

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The higher incidence of accidents occurring on board among the high-speed vessels has motivated this study focusing on the actual operating conditions contributing to the incidence. The working activities and workload of the officers and quartermasters were compared between the conventional and high-speed vessels of regular service ferry, by recording video-pictures and heart rate of the crews during actual navigations. An autopilot equipment was installed in the conventional vessel of over 6, 000 tons, but not in the high-speed vessel of about 1, 500 tons.Either on the conventional or high-speed vessel, dominant activities of the officers were lookout and watching radar, which were conducted in standing on the conventional vessel and in sitting on the high-speed vessel. Major works of the quartermasters were lookout and radar watch in standing on the conventional vessel and steering operations with a joystick in sitting on the high-speed vessel. Despite these differences in postural conditions, the mean % heart rate increase in both crews was significantly higher on the high-speed than on the conventional vessel. In the quartermaster, the events requiring steering maneuvers on the high-speed vessel were associated with increase in heart rate.The findings as a whole suggest occurrence of substantial mental strains in the crew on the high-speed vessel. These strains, certainly derived from caring for the safety in the absence of autopilot equipment, must have intensified the workload in the crew. In connection with the workload, the necessity for some fail-safe systems, including the autopilot facilities, and educational systems for techniques of steering high-speed vessels was discussed.

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Thermally comfortable zones in Vietnamese were investigated during winter in Hanoi. The subjects were 21 males (age: 19.7 ± 0.4 yrs; height: 165 ± 1.5 cm; body mass: 55.1 ± 1.1 kg) and 19 females (age: 19.7 ± 0.4 yrs; height; 155.6 1.7 cm; body mass: 45.6 ± 1.3 kg). Each participant entered singly the climatic chamber controlled at 22 °c and 40%RH. After 20 min rest, the participant was requested to indicate on a 7-point scale (Table 1) how he or she felt to the room temperature given. Then, the room temperature increased by 1 °c over 10 min every 20 min. Just before the rise of the room temperature, the participant judged his or her thermal sensation. More than 90% of the participants felt 24-29 °c of the room temperature as "slightly cool", "neutral" and "slightly warm" (Table 2). We defined these sensations as "thermally comfort". These thermally comfortable zones were quite higher than those (20-24 °c) recommended by ISO-7730 (1994). We discussed these discrepancies in terms of higher establishment of thermoregulatory set-point in the Vietnamese.

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Previous studies clarified more affinity toward fathers by boys and toward mothers by girls (FB&MG tendency) in indoor play interactions between infants (a few years old) and parents of Western countries. In the present study, behavioral interactions by Japanese parents and children including infants and elementary school pupils were examined in a naturalisitic outdoor park. The results indicated that the FB&MG tendency is also seen in infants of a non-Western country (Japan), in outdoor play interaction, and in older children. The meaning of the FB&MG tendency was discussed based on the results of the present study and the related previous ones.

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