• Journal of the Korea Safety Management & Science
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• v.11 no.2
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• pp.159-165
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• 2009

Through the understanding of the change of productivity and the ability of error recovery according to aging and the assessment and analysis of them, we may take this research to contribute to make a design for the road-map to help set up the policy of employment for old generation. For this we have taken an experiment of the coordination tester for 100 person who are chosen randomly and analysed the collected data using SAS, which is one of widely used statistical analysis packages. The main results are as follow: $\circledcirc$ The result of regression between the working speed and the length of the correction of error shows independence. (pr>0.2029). $\circledcirc$ The regression between age and working speed is statistically significant. (pr<0.0001) $\circledcirc$ The relation between age and the length of the correction of error is not significant. (pr>0.9123).

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.10a
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• pp.274-278
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• 2000

Ball end milling process is widely used in the die and mould manufacturing because of suitableness for the machining of free form surface. But, as ball end mill is long and thin, it is easily deflected by cutting force. In this study, Cutting force, tool deflection and surface precision was measured according to the change of depth and cutting location. Cutting force was acquired with tool dynamometer and a couple of eddy-current sensor measured tool deflection in x-y direction each. After machining, surface precision was measured with roundness tester and coordination measuring machine for sculptured surface angle change and cutting depth.

• Journal of the Korea Safety Management & Science
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• v.8 no.2
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• pp.81-90
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• 2006

As aging society makes rapid progress, various social problems arise. The drop of productive labor and the increase of welfare cost can be taken as examples. From this point of view, a use of aged labor is a matter of great Important to national productivity improvement. But, the participation rate of the aged in economical activity amounts to 49.8 percent and their unemployment rate does 2.1 percent. The purpose of this paper is to analyze the deterioration of skill and the lowering of adaption to new working environments due to aging. Since the aging effect is closely related to worker's productivity, it should be properly measured and analyzed. The coordination tester is used to find out activity limitations. Experimental results show that the expert skill of the workers can be improved through the effective of their experience. Therefore we can say that some operation is not influenced by aging.