Inverse Scattering from a Sound-Hard Crack via   Two-Step  Method

<table class="table-group" width="800px"><tr class="fig-image" id="a"><td><img alt="810676.fig.006a" src="https://static.hindawi.com/articles/aaa/volume-2012/810676/figures/810676.fig.006a.jpg"/></td></tr><tr class="fig-caption"><td align="center"><table><tr><td><b>(a) </b>Exact data, <svg height="11.375" id="M146" style="vertical-align:-0.1638pt" version="1.1" viewbox="0 0 50.724998 11.375" width="50.724998" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg></td></tr></table></td></tr><tr class="fig-image" id="b"><td><img alt="810676.fig.006b" src="https://static.hindawi.com/articles/aaa/volume-2012/810676/figures/810676.fig.006b.jpg"/></td></tr><tr class="fig-caption"><td align="center"><table><tr><td><b>(b) </b>3% error, <svg height="11.375" id="M147" style="vertical-align:-0.1638pt" version="1.1" viewbox="0 0 50.724998 11.375" width="50.724998" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg></td></tr></table></td></tr></table>

Abstract and Applied Analysis

Inverse Scattering from a Sound-Hard Crack via Two-Step Method

Figure 6