Flaw Identification in ALOK Imaging Systems

  • Yu Wei
  • Xing-quen Zhao
Part of the Acoustical Imaging book series (ACIM, volume 15)


In this paper the theoretical study and experimental work to improve the ability of flaw identification in an ALOK imaging system are presented. After flaws have reliably been detected by TTLC method, the migration imaging can be executed with lesser computation time only for a determined small space. Then two methods, ALC method and instantaneous phase correlations, are introduced to decide the features of pattern recognition. The experimental results of two kinds of artificial defects, holes and cracks, show that the improvement on flaw identification has been obtained.


Flaw Detection Flaw Identification Incline Angle Impinge Angle Metal Block 


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Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • Yu Wei
    • 1
  • Xing-quen Zhao
    • 1
  1. 1.Department of Biomedical EngineeringNanjing Institute of TechnologyNanjingChina

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