Transactions of the Korean Society of Machine Tool Engineers (한국공작기계학회논문집)

The Korean Society of Manufacturing Technology Engineers (한국생산제조학회)
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Acoustic Emission Source Location and Material Characterization Evaluation of Fiberboards

목재 섬유판의 음향방출 위치표정과 재료 특성 평가

  • 노승남 (서울산업대학교 기계공학과) ;
  • 박익근 (서울산업대학교 기계공학과) ;
  • 서성원 (서울산업대학교 기계공학과) ;
  • 김용권 (서울산업대학교 에너지 환경대학원)
  • Published : 2005.06.01
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Abstract

Acoustic Emission(AE) technique has been applied to not only material characterization evaluation but also on-line monitoring of the structural integrity. The AE source location technique is very important to identify the source, such as crack, leak detection. Since the AE waveforms obtained from sensors are very difficult to distinguish the defect signals, therefore, it is necessary to consider the signal analysis of the transient wave-form. In this study, we have divided the region of interest into a set finite elements, and calculated the arrival time differences between sensors by using the velocities at every degree from 0 to 90. A new technique for the source location of acoustic emission in fiberboard plates has been studied by introducing Wavelet Transform(WT) do-noising technique. WT is a powerful tool for processing transient signals with temporally varying spectra. If the WT de-noising was employed, we could successfully filter out the errors of source location in fiberboard plates by arrival time difference method. The accuracy of source location appeared to be significantly improved.

Keywords

References

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