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arXiv · 2405.05179

Detection of a piecewise linear crack with one incident wave

Xiaoxu Xu·Guanqiu Ma·Guanghui Hu
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Abstract

This paper is concerned with inverse crack scattering problems for time-harmonic acoustic waves. We prove that a piecewise linear crack with the sound-soft boundary condition in two dimensions can be uniquely determined by the far-field data corresponding to a single incident plane wave or point source. We propose two non-iterative methods for imaging the location and shape of a crack. The first one is a contrast sampling method, while the second one is a variant of the classical factorization method but only with one incoming wave. Newton's iteration method is then employed for getting a more precise reconstruction result. Numerical examples are presented to show the effectiveness of the proposed hybrid method.

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Xiaoxu Xu, Guanqiu Ma, Guanghui Hu. 2024-05-08. Detection of a piecewise linear crack with one incident wave. https://arxiv.org/abs/2405.05179

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