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최연선
- Journal of the Korean Society for Railway
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- v.2 no.2
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- pp.13-20
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- 1999
The vibration signals of driving parts of electric train are distorted its signal patterns due to the impact components, which occurs when wheel passes rail joints. An elimination method of the impact components is investigated using adaptive signal processing technique in this study The result shows that adaptive interference canceling method seems to be more effective than line enhancement technique. The application of adaptive interference canceling method to the signal measured at bogie shows that the extractions of the signals of driving parts of traction motor, reduction gear, and axle bearing are successful. Therefore, only the signals of bogie, which is the place to attach an accelerometer easily, is sufficient for the fault diagnosis and the safety evaluation of electric train. Also, adaptive interference canceling method can be applicable to evaluate the performance of vibration isolation between bogie and car body and to investigate the characteristics of indoor sound.
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Kim, Byung-Ghun;Kim, Yun-Chul;Chai, Jang-Bom
- Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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- 2008.04a
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- pp.413-415
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- 2008
In this paper, the new algorithm which eliminates structural noise and extracts the impact signature from the measured vibration signal is developed. We studied how the transient vibration signal due to the impact is distorted while propagating through the structure. Also the characteristics of noise generated by flow and the mechanical components are analyzed. The developed method is verified in the model plenum and the flow system in the laboratory. Results show the significant improvement in the sensitivity and accuracy.
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이영신;최명환;류충현
- Journal of KSNVE
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- v.8 no.4
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- pp.623-631
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- 1998
The free vibration analyses of the isotropic and composite(CFRP, GFRP) rectangular plates with point supports at the free edge and middle position are performed. The natural frequencies and nodal patterns of plates with point supports are experimentally determined by impact testing using an impact hammer. To compare and verify these experimental results, the finite element analysis is also carried out. The effect of the point support position, the number of point supports, and the anisotropic parameters on the natural frequencies and nodal patterns of cantilevered rectangular plates are investigated.
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이영신;최명환;류충현
- Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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- 1997.10a
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- pp.414-419
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- 1997
The free vibration analysis of cantilever CFRP and GFRP composite rectangular plates with point supports at the free edge and interior position is performed. The natural frequencies and mode shapes of plates are experimentally determined by impact testing using an impact hammer. To compare and verify these experimental results, the finite element analysis is also carried out and the non-dimensional frequency parameters are compared with FE analysis results. The effects of the number and location of the point support on the frequencies are examined. In the experimental results, it is found that a significant increase in frequencies occurs when the point supports are added on certain parts of plates.
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