The Use of L-Curve and U-Curve in Inverse Electromagnetic Modelling
Regularization methods are used for computing stable solutions to the ill-posed problems. The well-known form of regularization is that of Tikhonov in which the regularized solution is searched as a minimize of the weighted combination of the residual norm and a side constraint-controlled by the regularization parameter. For the practical choice of regularization parameter α we can use the well-known L-curve criterion, or introduced by us U-curve criterion. The efficiency of the approach is demonstrated on examples of synthesis of magnetic field. The paper is finished with the comparison of the two mentioned above methods made on numerical examples.
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