The Use of L-Curve and U-Curve in Inverse Electromagnetic Modelling

  • Dorota Krawczyk-Stańdo
  • Marek Rudnicki
Part of the Studies in Computational Intelligence book series (SCI, volume 119)


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.


Regularization Parameter Regularization Method SIAM Journal Tikhonov Regularization Fredholm Integral Equation 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Dorota Krawczyk-Stańdo
    • 1
  • Marek Rudnicki
    • 2
  1. 1.Center of Mathematics and PhysicsTechnical University of LodzŁódźPoland
  2. 2.Institute of Computer ScienceTechnical University of LodzŁódźPoland

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