RT Book, Section T1 Topological derivative based methods for non-destructive testing A1 Carpio Rodríguez, Ana María A1 Rapún Banzo, María Luisa AB We propose a numerical strategy to reconstruct scatterers buried in a medium when the incident radiation (electromagnetic, thermal, acoustic) is governed by Helmholtz transmission problems. The scattering problem is recast as a shape optimization problem with the Helmholtz equation as a constraint and the scatterer as a design variable. Our method is based on the (successive) computation of topological derivatives of the associated shape functional for updated guesses of the scatterer.We present an efficient scheme to compute the required topological derivatives at each step. The scheme combines explicit expressions for the topological derivatives in terms of the solutions of forward and adjoint transmission problems with boundary elementfinite element approximations. Our technique applies in either spatially homogeneous or inhomogeneous media. Finally, a two dimensional numerical test illustrates the ability of the method to reconstruct buried shapes PB Springer SN 978-3-540-69776-3 YR 2008 FD 2008 LK https://hdl.handle.net/20.500.14352/53108 UL https://hdl.handle.net/20.500.14352/53108 LA eng NO Proceedings of ENUMATH 2007, the 7th European conference on numerical mathematics and advanced applications, Graz, Austria, September 10–14, 2007 DS Docta Complutense RD 17 abr 2025