There are large individual differences in the detection performance of inspectors in inspection tasks. In particular, large individual differences are expected in the time characteristics of detection performance among the inspectors.
Few reports are available which have evaluated these individual differences from the standpoint of the relationship between detection performance and inspection time.
This study has established equations for a measure of the effect of time allowed on detection performance. This measure is defined as time characteristic parameter m. Experiments have been conducted to evaluate the effectiveness of the m value. In the experiments, fifteen inspectors were employed as subjects. Twenty-five test sheets were prepared with 200 Japanese hiragana letters arranged at random. The subjects counted the number of the letters on each test sheet.
The experimental results show that there are very large individual differences in the effect of time allowed on the inspectors. This finding confirms the effectiveness of the time characteristic parameter m for evaluating the detection performance of inspectors.

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As a part of study in clarifying characteristics of wotk area affecting work accuracy, a two-handed simultaneous work of making contacts with four targets is experimentally studied to determine the effect of distance and direction of targets on the work accuracy.
It is found that there is an optimum pace which gives the best performance for the work which requires medium level accuracy; the direction which gives the highest accuracy is in the front of the body of an operator and the accuracy decreases as direction shifts toward the side of the body; and outward-to-body motion is more accurate in the case of front direction movement and inward-to-body motion is more accurate than outward-to-body motion in the case of side direction movement. The influence of work area over the accuracy of the abovementioned experiment is explained in terms of eye motion pattern and eye-hand coordination.

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Recently, the signal processing techniques like auto-regression analysis, Kalman Filter are applied for extracting the specified information contained in EEG. However, it is not easy for these techniques to extract the frequency information immediately, even with the help of the mini or middle class computer.
In this paper, an extracting method using PLL (Phase Locked Loop) circuit is proposed, which converts the frequency of EEG to analog voltage directly (without computer). Moreover, the proposed method offers the analog voltages corresponding to the amplitude and the non-stationarity of EEG signal with great ease and small expense.

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