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The Measurement and Analysis of Acoustic Noise as a Random Variable

  • Steven P. Neal
  • Donald O. Thompson
Chapter
Part of the Review of Progress in Quantitative Nondestructive Evaluation book series

Abstract

In ultrasonic nondestructive evaluation, experimental measurements of the scattered wave field resulting from sonification of a flaw are corrupted with acoustic noise. Acoustic noise results from non-flaw related scattering or reflection of the incident waves. In many probabilistic approaches to flaw detection, classification, and characterization, a stochastic model for a noise-corrupted flaw signal is utilized where acoustic noise is assumed to be an uncorrelated, Gaussian random variable with zero mean. In addition, it is assumed that an estimate of the average power spectra of the noise is available [1–3]. The goal of the work presented here was to measure and analyze acoustic noise as a random variable. Emphasis was placed on evaluating these assumptions and on estimating the average power spectra of the noise.

Keywords

Noise Signal Acoustic Noise Electronic Noise Average Power Spectrum Grid Position 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1990

Authors and Affiliations

  • Steven P. Neal
    • 1
  • Donald O. Thompson
    • 2
  1. 1.Department of Mechanical and Aerospace EngineeringUniversity of Missouri-ColumbiaColumbiaUSA
  2. 2.Center for NDEIowa State UniversityAmesUSA

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