Human hands have highly sensitive skin sensation and deep sensation, and also have viscoelastic skeletal muscles and a skeletal structure of multi-joint linkages with many redundant degrees of freedom. Therefore, human hands can perform minute operations in handling works. A measuring technique for movements of hands is useful for a development of interface devices that can transfer human intention to a machine system. In order to measure movements of fingers, we have developed an exoskeletal type photo-goniometer that can be fitted with the thumb, the indexfinger and the middle finger without any impediments in finger actions. We have put on this goniometer with multi-joint linkages, and performed the calibration of measurement tools. We have transferred data from fiber-optic goniosensors on the joints to the personal computer, and we have analyzed the co-operations of fingers in three-dimensional movements by using these data. We expect more precise measurements of finger movements by improving the accuracy in works of this goniometer.

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The purpose of this paper was to clarify sex differences in the vocational preference of the visually impaired. Data were collected from 146 visually impaired college students and 92 sighted undergraduate students. The Vocational Preference Inventory (Japanese Version) was used to measure six personality types: realistic, investigative, artistic, social, enterprising, and conventional. Occupations that were connected directly with social independence had attraction to the visually impaired. It was suggested that the study of the process of vocational development was necessary in relation to the psychological and social developments in the visually impaired. Sex differences were shown in 5 personality types. The exception was the conventional personality type. In the analysis of the inner structure using inter-measure correlations that showed positive, sex differences were found at Holland' s hexagonal model in both groups. So it was rejected that the sex differences were not found in the vocational preference of the visually impaired because there were not so many vocations that they could select. It was concluded that the same working hypothesis that was used in the career development of the sighted group could be adopted.

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The purpose of this study is to reveal the control properties of the voluntary single hand rhythmic movement from the viewpoint of the variability aspects for frequency and amplitude. Twelve subjects (age: 20-24yrs.) participated in three experimental conditions: Preferred pace (pP), Maximum-pace (maxP), and Pace-up (Pu) conditions. Coefficients of variation (CVs) were used as variability measures for frequency and amplitude. The CVs for frequency and amplitude indicated similar deviations at slow rhythmic movement rates. Though the amplitude CVs gradually increased as the movement rates increased, the frequency CVs remained invariant. The results of these experiments indicated that frequency was the control parameter in the rhythmic movement. In addition, it was also found that the amplitude CVs began to increase at approximately 1.24Hz.

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As to operations in dynamic environments, especially in coping with anomalies, it has been considered as a crucial issue to ensure the operabilities and adaptibities of interfaces suitable to human cognitive performance. Factors contributing to improvements of the human interface may have diverse varieties, however, one of the most desirable and crucial factors is reducing operators' workload in coping with anomalies, because relatively high performance should be required in emergency situations. This paper presents the methodology for evaluating dynamic workload of four different cognitive functions separately such as perception, thought, memory, and behavior by simulating operator's cognitive and behavioral activities. Simulations were executed in coping with anomalies occurring at a simplified boiling water reactor (BWR). Simulation results involve plant transients, communications between operators, and both operations and actions including cognitive behavior of each operator. These results were compared with those obtained in the experiments including typical four kinds of malfunctions, and so it was shown that both were in good agreements. In the simulations, the activating frequencies of each cognitive function were accumulated during a periodic interval. It was suggested that obtained frequencies would be considered to indicate a relative strength of each workload component. It means that this methodology could be applicable to making relative comparisons between several types of human interfaces without manufacturing mockups, in the respect of operators' workload.

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