# Diffraction by a Strip and by a Half-plane with Variable Face Impedances

• Luís P. Castro
Conference paper
Part of the Operator Theory: Advances and Applications book series (OT, volume 181)

## Abstract

A study is presented for boundary value problems arising from the wave diffraction theory and involving variable impedance conditions. Two different geometrical situations are considered: the diffraction by a strip and by a half-plane. In the first case, both situations of real and complex wave numbers are analyzed, and in the second case only the complex wave number case is considered. At the end, conditions are founded for the well-posedness of the problems in Bessel potential space settings. These conditions depend on the wave numbers and the impedance properties.

## Keywords

Wave diffraction boundary value problem Helmholtz equation impedance problem well-posedness pseudo-differential equations

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