|COMPANY / INSTITUTION||Computational and Applied Mathematics,
Title: Nonlinear Multigrid for imaging electrical conductivity and permittivity
at low frequency
We propose a nonlinear multigrid approach for imaging the electrical conductivity and permittivity of a body, given partial, usually noisy knowledge of the Neumann to Dirichlet map at the boundary. The algorithm is a nested iteration, where the image is constructed on a sequence of grids, starting from the coarse grid and advancing towards the finest one. We show various numerical examples that demonstrate the effectiveness and robustness of the algorithm and prove local convergence.