RESUMEN

We consider an isotropic Lamé system for an elastic medium consisting of finitely many imperfections of small diameter, embedded in a homogeneous reference medium. The Lamé coefficients of the imperfections are different from those of the background medium. First, we establish an asymptotic formula for the displacement vector in terms of the reference Lamé coefficients, the location of the imperfections, and their geometry. Second, we use this asymptotic expansion to establish continuous dependence estimates for certain characteristics of the imperfections in terms of the boundary data and to derive integral boundary formulae that yield to a very effective identification procedure.

In this paper we rigorously derive asymptotic formulae for resonances associated with a microstrip transmission line mounted on a planar waveguide with variable electromagnetic characteristics when the width of the line goes to zero.