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DOE OSTI · 1803776

A domain decomposition preconditioning for an inverse volume scattering problem

Abstract

In this work, we propose domain decomposition preconditioners for the solution of an integral equation formulation of the acoustic forward and inverse scattering problems. We study both forward and inverse volume problems and propose preconditioning techniques to accelerate the iterative solvers. For the forward scattering problem, we extend the domain decomposition based preconditioning techniques presented for partial differential equations in Cai and Sarkis (1999 SIAM J. Sci. Comput. 21 792–797), to integral equations. We combine this domain decomposition preconditioner with a low-rank correction, which is easy to construct, forming a new preconditioner. For the inverse scattering problem, we use the forward problem preconditioner as a building block for constructing a preconditioner for the Gauss–Newton Hessian. We present numerical results that demonstrate the performance of both preconditioning strategies.

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BibTeXRIS

Borges, Carlos, Biros, George. 2020-02-14. A domain decomposition preconditioning for an inverse volume scattering problem. https://doi.org/10.1088/1361-6420%2Fab6e78

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