In the assembling work, there are a lot of works to control the power. The control of the power is more difficult than the control of the position or the speed, because it is difficult to capture level of the power visually. There is a difficulty for grasping the level and control of the power by usual OJT. In the assembling work, the control of power in pushing operations is most frequently occurred even though there are various power controls like push, pull and turn.
In this thesis, to control to one level of pushing-power is selected as an experimental task. The purpose of this study is to analyze the influence of the visual feedback to the trainee's action and the result of training, and to obtain basic findings about how and what kind of the visual feedback is useful for trainee's grasping of level of power.
In the experiment, four patterns of visual feedbacks were compared. As a result of the experiment, the following finding was obtained. The precision and the stability of the pushing-power control are improved by the exclusion of the visual feedback at rising period and giving of the visual feedback at the continuation period.

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Saccadic eye movements are characterized by its velocity, latency, duration and gain, all of which are represented by the cognitive mechanism in the brain and each quantity of which is determined with the criterion detecting saccades. These features have been used as one of indices to evaluate a variety of phenomena including visual fatigue in VDT task, level of understanding in reading comprehension, severity for mental disorders, and human performance under virtual reality environment. Moreover, these features are expected to open up the possibility for understanding and modeling the cerebral function. The criterion, in which eye velocity is currently used for detecting saccades in most studies, has taken some problems especially on resetting index level according to an object, on detecting corrective micro-saccades, saccades being overshot and catch-up saccades induced in between smooth pursuit movements. In this study, we propose detection criterion based on the acceleration of eye movement and we empirically demonstrate that this criterion can examine aforementioned problems.

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This study examined the effects of worn-out shoes on the lower limbs during walking. Eight male subjects walked at their own pace for 10m wearing four different pairs of worn-out shoes (a combination of two thicknesses of heel portion and two lengths of the outer lateral portion) and one pair of normal shoes. Shock acceleration at the subtalar joint, leg angle, electromyography (EMG) of the lower limbs, and the center of pressure were measured during three randomly selected steps while walking. There was no difference in vertical shock acceleration among the conditions, which failed to show a reduction in shock absorption. However, in shoes with the outer lateral portion worn to 78mm, supination of the subtalar joint and external rotation of the lower leg were increased, and the center of pressure shifted laterally. The results of this study indicated that abrasion resistance of the outer lateral portion is important to maintain stability.

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This study examines the work postures and psychological burden of frontal birth assistance techniques in student and experienced midwives. The results showed that for both student and experienced midwives, birth assistance techniques most commonly involve the standing posture. In both cases the delivery table was at breast height and the work area was adequate, but there were many complaints of fatigue relating to tiredness and pain in the left knee and lower thigh, hand and wrist. Both showed high levels of cortisol in the saliva after birth assistance. Also, the fact that the level remained high for student midwives even an hour after birth assistance implies that they were exposed to excessive stress. Further, the student midwives exhibited strong feelings of stress and lower alertness both before and after birth assistance. This suggests difficulties in maintaining concentration and sense of judgment due to tension before starting work and the high mental workload during work.

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