An Analysis of Ultrasonic Flaw Scattering Amplitude as a Random Variable

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


The use of prior information is an important component in the ultrasonic detection, classification, and characterization of flaws. In order to take full advantage of advanced digitally based approaches to flaw detection, classification, and characterization, use of prior information will be critical. Some advanced techniques involve probabilistic approaches which start with a stochastic model for a flaw signal in which the flaw’s scattering amplitude is assumed to be an uncorrelated, Gaussian random variable with zero mean and known variance [1–4]. The goal of the work presented here was to analyze scattering amplitude as a random variable with emphasis on evaluation of these assumptions.


Lognormal Distribution Flaw Size Flaw Distribution Spherical Void Deterministic Nature 
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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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