A Frequency Domain Parameter Estimation procedure in Viscoelastic Layered Media

MARÍA G. ARMENTANO, ELENA FERNADEZ BERDAGUER, JUAN SANTOS

COMPUTATIONAL AND APPLIED MATHEMATICS

ICMC

Año: 1995 vol. 14 p. 191 - 216

The problem of estimating the complex plane-wave modulus in viscoelastic layeredmedia with absorbing boundary conditions is solved using a quasilinearization technique. The differential model is naturally posed in the space-frequency domain, with the inclusion of dissipative effects via the use of a complex frequency-dependent plane-wave modulus in the stress-strain relations.Consequently, the parameter estimation problem is also formulated in the space-frequencydomain. A set of existence and uniqueness results and estimates of the solution of the differentialmodel and its derivative with respect to the parameter are presented. The estimation problemis formulated as a minimization problem and is solved using an iterative quasilinearization algorithm.Approximations to the solution of the differential model and its derivative are computedusing finite element procedures. Numerical examples illustrating the application of the proposedalgorithm are also presented.