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Application of homomorphic signal processing to stress wave factor analysisThe stress wave factor (SWF) signal, which is the output of an ultrasonic testing system where the transmitting and receiving transducers are coupled to the same face of the test structure, is analyzed in the frequency domain. The SWF signal generated in an isotropic elastic plate is modelled as the superposition of successive reflections. The reflection which is generated by the stress waves which travel P times as a longitudinal (P) wave and s times as a shear (S) wave through the plate while reflecting back and forth between the bottom and top faces of the plate is designated as the reflection with P, s. Short-time portions of the SWF signal are considered for obtaining spectral information on individual reflections. If the significant reflections are not overlapped, the short-time Fourier analysis is used. A summary of the elevant points of homomorphic signal processing, which is also called cepstrum analysis, is given. Homomorphic signal processing is applied to short-time SWF signals to obtain estimates of the log spectra of individual reflections for cases in which the reflections are overlapped. Two typical SWF signals generated in aluminum plates (overlapping and non-overlapping reflections) are analyzed.
Document ID
19860028453
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Williams, J. H., Jr.
(Massachusetts Inst. of Tech. Cambridge, MA, United States)
Lee, S. S.
(MIT Cambridge, MA, United States)
Karaguelle, H.
(Massachusetts Inst. of Tech. Cambridge, MA, United States)
Date Acquired
August 12, 2013
Publication Date
October 1, 1985
Publication Information
Publication: Materials Evaluation
Volume: 43
ISSN: 0025-5327
Subject Category
Quality Assurance And Reliability
Accession Number
86A13191
Distribution Limits
Public
Copyright
Other

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