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Kim, O.S.;Rim, S.J.;Kim, Y.S.;Lee, Y.G.;Kim, J.C.;Chung, C.S.;Chung, S.J.
- Proceedings of the KIEE Conference
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- 1995.07b
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- pp.616-619
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- 1995
This paper describes developement of on-line system for vibration signal analysis. In the power system, the main reason of transformer fault is due to a large amount of current by a short-circuit and a ground-fault. The electromagnetic force caused by fault-current deforms transformer windings and results in vibration pattern change. Therefore if the continuous on-line vibration monitoring on transformer is performed, an incipient failure can be detected. The developed system is composed of data acquisition devices, user interface program, signal processing program, diagnosis and trend analysis program, self diagnosis program and communication program.
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An, Ok-Hee;Kim, Hyun-Jin;Kim, Gi-Hoon;Kim, Hoon;Kim, Hyun-Ji
- Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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- 2006.05a
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- pp.125-130
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- 2006
In this study, tests of brain waves were carried out to investigate the driver's physiological characteristics by the change of the headlight. The participants were 20 men in their 20s and twenty-three different conditions in combinations of waveform of light, voltage, and alteration time were used. The measurement of the brain waves was performed by internationally standardized 10-20 method using LXE3232-RF. The results were analyzed by Power Spectrum Analysis using alpha-, and beta-wave and by the analysis of different brain domains using Brain wave Map. The results were as follows. 1. From the results of the Brain wave Map analysis, it was suggested that A waveform increases mental stress and B waveform affects mental and visual stress. The longer the stimulation time, the more stress level was detected. 2 The voltage alteration time of B waveform should be kept less than 1500msec, and the voltage should not fall below 11.5V.
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Kim, S.M.;Jang, S.H.;Kim, S.G.;Ha, J.S.;Choi, Y.H.
- Proceedings of the KSME Conference
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- 2007.05a
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- pp.1590-1594
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- 2007
This paper describes a case study on dynamic characteristics analysis of a 5-axis multi-tasking machine tool of ram-head typed. Natural frequency and corresponding vibration modes of the machine tool structure were obtained by using both FEM modal analysis and an experimental modal test(impulse hammer test). Both the theoretical and experiment analysis results showed good agreement with each other. Finally, some discussion and review, from the view point of resonance vibration and/or mode coupled chatter, were made based on the analysis results.
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Yoo, B.C.;Park, I.S.;Kim, Y.S.
- Journal of the Ergonomics Society of Korea
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- v.15 no.2
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- pp.149-155
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- 1996
The purpose of this study is to provide basic information for elderly women's clothing design and to develop dress forms that can reflect the characteristics of their bodies. Three hundered twenty subjects, between the ages of 60 .approx. 85, were chosen and the data were collected from anthropometric data. Principal component analysis which is one of the basic methods in factor analysis was applied to the interpretation of anthropometric data. As a result of analysis, the data are able to be decided into appropriate group.
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Wang, Se-Myung;Kwon, Dae-Il;Kim, Chaw-Il
- Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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- 2006.05a
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- pp.1432-1436
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- 2006
Feasibility of optimizing Zwicker's loudness has been shown by using MSC/NASTRAN, SYSNOISE, and a semi-analytical design sensitivity by Wang and Kang. Design sensitivity analysis of Zwicker's loudness is developed by using ANSYS, COMET, and an adjoint variable method in order to reduce computation. A numerical example shows significant reduction of computation time for design sensitivity analysis.
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