American Journal of Applied Sciences

Inclusion Identification by Inverse Application of Boundary Element Method, Genetic Algorithm and Conjugate Gradient Method

Mahmud Khodadad and Mohsen D. Ardakani

DOI : 10.3844/ajassp.2008.1158.1166

American Journal of Applied Sciences

Volume 5, Issue 9

Pages 1158-1166

Abstract

Characterization of the interior of an inhomogeneous body using displacement measurements obtained by conducting a simple tension test was investigated. A homogeneous elastic solid body is assumed to have another solid body with arbitrary shape hidden inside it. The shape and physical properties of this inclusion were unknown. The Boundary Element Method (BEM) coupled with a mete heuristic Genetic Algorithm (GA) and Conjugate Gradient Method (CGM) was used in this characterization problem. A fitness function, which is the summation of squared differences between the measured displacements and calculated displacements at the same locations on the boundary, is minimized using GA and CGM. GA is used to find a good initial estimate of the unknown parameters and the CGM was used as the hybrid function to get converged values of the unknown parameters. For the cases that the fitness function fluctuates severely, a regularization function was added to CGM in order to dampen the fluctuations.

Copyright

© 2008 Mahmud Khodadad and Mohsen D. Ardakani. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.