Electromagnetic inverse problems involving distributions of dielectric mechanisms and parameters

Electromagnetic Inverse Problems Involving Distributions of Dielectric Mechanisms and Parameters

We consider electromagnetic interrogation problems for complex materials involving distributions of polarization mechanisms and also distributions for the parameters in these mechanisms. A theoretical and computational framework for such problems is given. Computational results for specific problems with multiple Debye mechanisms are given in the case of discrete, uniform, log-normal, and log-b...

Inverse Electromagnetic Problems

Inverse Medium Scattering Problems for Electromagnetic Waves

Consider a time-harmonic electromagnetic plane wave incident on a medium enclosed by a bounded domain in R3. In this paper, existence and uniqueness of the variational problem for forward scattering are established. An energy estimate for the scattered field with a uniform bound with respect to the wavenumber is obtained in the case of low frequency on which the Born approximation is based. A c...

Shape Optimization for Inverse Electromagnetic Casting Problems

In this paper we present an algorithm for inverse optimization problems concerning electromagnetic casting of molten metals. We are interested in locating suitable inductors around the molten metal so that the equilibrium shape be as near as possible to a desired target shape. A Simultaneous Analysis and Design (SAND) mathematical programming formulation is stated for the inverse problem. The r...

Piecewise smooth models for electromagnetic inverse problems

This paper presents a new method for constructing onedimensional electrical conductivity models of the Earth from surface electromagnetic measurements. The construction of these models is a nonlinear inverse problem that can be approached by linearization techniques combined with iterative methods and Tikhonov’s regularization. The standard application of these techniques usually leads to smoot...