• Journal of Institute of Control, Robotics and Systems
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• v.15 no.7
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• pp.675-682
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• 2009

Instead of direct driving like BLDC, the induction principle is adopted as a driving one for planar stage. The stage composed of four linear induction motors put in square type is activated by two-axial forces; low-frequency attractive force and thrust force of the linear induction motors. Here, the modified vector control whose new inputs are q-axis current and dc current biased to three phase current instead of d-axis current or flux current is applied extensively to overall motion of the stage. For the developed system, the precision step test and the constant velocity test are tried to guarantee its feasibility for TFT-LCD pattern inspection. However, to exclude a discontinuity due to phase shift and minimize a force ripple synchronized with the command frequency, the initial system is revised to the antagonistic structure over the full degree of freedom. Concretely describing, the porous air bearings guide an air-gapping of the stage up and down and a pair of liner induction motors instead of single motor are activated in the opposite direction each other. The performances of the above systems are compared from trapezoid tracking test and sinusoidal test.

• Korean Journal of Human Ecology
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• v.1 no.2
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• pp.100-112
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• 1998

The purpose of this study is to investigate the torso patterns by analyzing sensory evaluations. The anthropometric measurements for female college students were obtained between March and October in 1998, and a total of 197 anthropomatric data was used for the somatotype analysis. The appearance and fit of three kinds of torso patterns(ESMOD, FIT, and Muller & sohn) were evaluated by expert panel and the subjects. The results of the anthropometric measurements and sensory evaluations are as follows; The mean height of the anthropometric data for 197 students is 158.98cm. The largest proportion of the three somatotypes(H, M and A type) is big hip type(A type) consisting of 47.7% of all the respondents. The result of the torso pattern evaluations by expert panel indicates that the ESMOD pattern obtains the highest rating in general acceptability. A significant difference(p<.05) in the responses to two questions, the placement of the waist dart, and the gapping & creasing at back hip area was found. The ESMOD and Muller & sohn patterns are given the highest rating in the general acceptability. The result of the evaluation was obtained by the subjects. (Korean J. Human Ecology 1(2):100∼112, 1998)