• Title/Summary/Keyword: Windowed or Short-Time Fourier Transform

Search Result 2, Processing Time 0.015 seconds

A Study on the Wavelet Transform of Acoustic Emission Signals Generated from Fusion-Welded Butt Joints in Steel during Tensile Test and its Applications (맞대기 용접 이음재 인장시험에서 발생한 음향방출 신호의 웨이블릿 변환과 응용)

  • Rhee, Zhang-Kyu
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.16 no.1
    • /
    • pp.26-32
    • /
    • 2007
  • This study was carried out fusion-welded butt joints in SWS 490A high strength steel subjected to tensile test that load-deflection curve. The windowed or short-time Fourier transform(WFT or STFT) makes possible for the analysis of non-stationary or transient signals into a joint time-frequency domain and the wavelet transform(WT) is used to decompose the acoustic emission(AE) signal into various discrete series of sequences over different frequency bands. In this paper, for acoustic emission signal analysis to use a continuous wavelet transform, in which the Gabor wavelet base on a Gaussian window function is applied to the time-frequency domain. A wavelet transform is demonstrated and the plots are very powerful in the recognition of the acoustic emission features. As a result, the technique of acoustic emission is ideally suited to study variables which control time and stress dependent fracture or damage process in metallic materials.

A Study on the Wavelet Transform of Acoustic Emission Signals Generated from Fusion-Welded Butt Joints in Steel during Tensile Test and its Applications (맞대기 용접 이음재 인장시험에서 발생한 음향방출 신호의 웨이블릿 변환과 응용)

  • Rhee Zhang-Kyu;Yoon Joung-Hwi;Woo Chang-Ki;Park Sung-Oan;Kim Bong-Gag;Jo Dae-Hee
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • 2005.05a
    • /
    • pp.342-348
    • /
    • 2005
  • This study was carried out fusion-welded butt joints in SWS 490A high strength steel subjected to tensile test that load-deflection curve. The windowed or short-time Fourier transform (WFT or SIFT) makes possible for the analysis of non-stationary or transient signals into a joint time-frequency domain and the wavelet transform (WT) is used to decompose the acoustic emission (AE) signal into various discrete series of sequences over different frequency bands. In this paper, for acoustic emission signal analysis to use a continuous wavelet transform, in which the Gabor wavelet base on a Gaussian window function is applied to the time-frequency domain. A wavelet transform is demonstrated and the plots are very powerful in the recognition of the acoustic emission features. As a result, the technique of acoustic emission is ideally suited to study variables which control time and stress dependent fracture or damage process in metallic materials.

  • PDF