Warped Wigner-Hough Transform for Defect Reflection Enhancement in Ultrasonic Guided Wave Monitoring

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</svg> are the direct and inverse Fourier Transform operators, respectively, while <svg height="16.6625" id="M43" style="vertical-align:-3.56265pt" version="1.1" viewbox="0 0 34.900002 16.6625" width="34.900002" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> are the warping map and its first derivative.</table>

Mathematical Problems in Engineering

fig5

Figure 5

Figure 5: Warped Wigner-Hough Transform for Defect Reflection Enhancement in Ultrasonic Guided Wave Monitoring 