ACTA UNIVERSITATIS APULENSIS No 10/2005 HYBRID GA-SQP ALGORITHMS FOR THREE-DIMENSIONAL BOUNDARY DETECTION PROBLEMS IN POTENTIAL CORROSION DAMAGE
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چکیده
In this paper we consider the identification of the geometric structure of the boundary of the solution domain for the three-dimensional Laplace equation. Cauchy data consisting of boundary measurements of currents and voltages on the remainder of the boundary are used to determine the material loss caused by corrosion. This problem arrise in the early detection of corrosion in aging aircraft components. The domain identification problem is considered as a variational problem to minimize a defect functional, which utilises some additional data on certain known parts of the boundary. A sequential quadratic programming (SQP) optimisation algorithm and a real coded genetic algorithm (GA) are combined in order to obtain a fast algorithm that can deal with the multimodal objective function. The unknown boundary is parameterized using B-splines. The Laplace equation is discretised using the method of fundamental solutions (MFS). Numerical results are presented and discussed for four hybrid algorithms and several test examples. 2000 Mathematics Subject Classification: 65N21, 68T20, 90C56.
منابع مشابه
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تاریخ انتشار 2005