The Japanese Journal of Ergonomics
Online ISSN : 1884-2844
Print ISSN : 0549-4974
ISSN-L : 0549-4974
Volume 34, Issue 3
Displaying 1-6 of 6 articles from this issue
  • Futomi SHIMONO, Mieko OHSUGA, Hiromi TERASHITA
    1998 Volume 34 Issue 3 Pages 107-115
    Published: June 15, 1998
    Released on J-STAGE: March 12, 2010
    JOURNAL FREE ACCESS
    The present paper concerns the method for the assessment of mental work stress using autonomic responses such as heart rate, heart rate variability, respiration and blood pressure. Two types of mental work stress, that is, high-tension stress and monotonous one were investigated. To simulate the high-tension work stress, tracking task was used intriducing two kinds of instructions which induce more stress. The indices obtained from electrocardiogram, blood pressure and respiration were investigated and most of them except blood pressure showed task dependent changes which can be explained by sympathetic activation and parasympathetic withdrawal, while only HR showed the effect of the instructions. The same tracking task was used but repeatedly to simulate monotonous work, that is, a sequence of eight tracking task trials. At the beginning of the sequence most indices showed task dependent changes which are similar to those in the high-tension experiment. As the trials were repeated, blood pressure went up, the irregularity of the respiration enlarged, and the Mayer wave related Heart rate variability increased, which may reflect irritation, boredom, and disgust.
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  • Koji OMINO, Hisao NAGATA, Hisato OHNO
    1998 Volume 34 Issue 3 Pages 117-127
    Published: June 15, 1998
    Released on J-STAGE: March 12, 2010
    JOURNAL FREE ACCESS
    For the purpose of working out the passenger injury-minimizing technology in the event of a train collision, it is important first of all to estimate the probable reaction of passengers involved in the accident. Computer simulation is one of the means conceivable for investigation of this problem.
    To get the basic data for the investigation, we have performed an experiment to know the toppling characteristics of passengers reacting to shock and accelerations in such a collision. The experiment revealed that the toppling liability and direction of passengers in response to rectangular waveform of acceleration stimulus depend on the standing apart width of their feet, and the duration and acting direction of the acceleration.
    Meanwhile, the range of accelerations at which the human body may be regarded as a simple mass is assumed as the range of accelerations at which humans can no longer control the direction of their toppling and practically they fall in that direction. Then a minimum value of this acceleration is defined as the limit value for toppling control and as to adult female students, we presumed a value of 280cm/s2 as this minimum. Further as a result of comparing the toppling directions of humans and a dummy model currently utilized in computer simulation by auto industry, we point out that there is a discrepancy in the toppling direction between humans and the dummy when the stimulus duration is 0.2-0.5s and the stimulus applied is short of 1400cm/s2.
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  • Pongthorn JITTACHALOTHORN
    1998 Volume 34 Issue 3 Pages 129-142
    Published: June 15, 1998
    Released on J-STAGE: March 12, 2010
    JOURNAL FREE ACCESS
    In this study, the simple manipulative task of “pick and place” has been performed with instructions available through a computer by “assembling position-part assembled-place of part stored” memorization sequence. Proposed memorization border model and pattern classification of the memorization border curve can be applied to analyze the effect of the number of assembled parts on the memorization process. From the results of analysis, the memorization process is divided into two categories, middle and neighborhood preceding memorization process. The memorization border curve is useful to analyze memorization trend in term of number of parts. The comparison between individual memorization border curves gives ideas of the individual inclination. The combination work method of the middle preceding memorization process on the first half work elements and the neighborhood preceding memorization process on the latter half work elements is proposed as the efficient task guideline.
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  • Tsuyoshi HORIO, Yojiro KAWAMURA
    1998 Volume 34 Issue 3 Pages 143-150
    Published: June 15, 1998
    Released on J-STAGE: March 12, 2010
    JOURNAL FREE ACCESS
    Influences of nutritional calorie intake and aerobic exercise training using a bicycle ergometer on percent body fat were evaluated. Five-month training for two-five days per week was performed at intensity 50% VO2max (maximal oxygen uptake) for 20 minutes per day. Whereas the percent body fat was 22.0% in men and 28.2% in women (borderline obesity, respectively) before the training, it changed to 19.3% in men (normal) and 23.8% in women (normal) after the training. The female subjects who showed the less decrease of percent body fat had taken the more calories than those who showed significant decrease of the percent body fat. The values of diastolic blood pressure, systolic blood pressure, heart rate at rest, fasting plasma glucose, total cholesterol, HDL (high density lipoprotein) cholesterol and triglyceride of plasma were all not different between the pre-and post-training.
    These results suggested that decrease rate of percent body fat induced by regular physical exercise training were influenced by nutritional intakes.
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  • Atsuo MURATA
    1998 Volume 34 Issue 3 Pages 151-155
    Published: June 15, 1998
    Released on J-STAGE: March 12, 2010
    JOURNAL FREE ACCESS
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  • Ryoji YOSHITAKE
    1998 Volume 34 Issue 3 Pages 157-158
    Published: June 15, 1998
    Released on J-STAGE: March 12, 2010
    JOURNAL FREE ACCESS
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