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arXiv · 1612.06604

Direct and Inverse Elastic Scattering From Anisotropic Media

Gang Bao·Guanghui Hu·Jiguang Sun·Tao Yin
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Abstract

Assume a time-harmonic elastic wave is incident onto a penetrable anisotropic body embedded into a homogeneous isotropic background medium. We propose an equivalent variational formulation in a truncated bounded domain and show the uniqueness and existence of weak solutions by applying the Fredholm alternative and using properties of the Dirichlet-to-Neumann map in both two and three dimensions. The Fr\'echet derivative of the near-field solution operator with respect to the boundary of the scatterer is derived. As an application, we design a descent algorithm for recovering the interface from the near-field data of one or several incident directions and frequencies. Numerical examples in 2D are presented to show the validity and accuracy of our methods.

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Gang Bao, Guanghui Hu, Jiguang Sun, Tao Yin. 2016-12-20. Direct and Inverse Elastic Scattering From Anisotropic Media. https://arxiv.org/abs/1612.06604

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