Abstract
This paper is concerened with a computational method for recovering induced magnetic fields due to the existence of surface or subsurface cracks on material in critical structure. The inversion formula can be simply represented by an integral equation of the first kind. However, in practical magnetic measurements, the severe ill-posed problem is caused by the observation noise. The problem is transformed into a well-posed difference equation using output least squares approach with a regularization of bounded variations. A fast computational algorithm is also proposed using discrete Fourier transform. Results of numerical experiments to demonstrate the efficacy of the proposed algorithm are reported.
