Abstract：
:The solution of impedance distribution in electrical impedance tomography is a nonlinear inverse problem that requires the use of a regularization method. The generalized Tikhonov regularization methods have been popular in the solution of many inverse problems. The regularization matrices that are usually used with the Tikhonov method are more or less ad hoc and the implicit prior assumptions are, thus, in many cases inappropriate. In this paper, we propose an approach to the construction of the regularization matrix that conforms to the prior assumptions on the impedance distribution. The approach is based on the construction of an approximating subspace for the expected impedance distributions. It is shown by simulations that the reconstructions obtained with the proposed method are better than with two other schemes of the same type when the prior is compatible with the true object. On the other hand, when the prior is incompatible with the true object, the method will still give reasonable estimates.
journal_name
IEEE Trans Med Imagingjournal_title
IEEE transactions on medical imagingauthors
Vauhkonen M,Vadász D,Karjalainen PA,Somersalo E,Kaipio JPdoi
10.1109/42.700740subject
Has Abstractpub_date
1998-04-01 00:00:00pages
285-93issue
2eissn
0278-0062issn
1558-254Xjournal_volume
17pub_type
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