Abstract
Tikhonov regularization often is applied with a finite difference regularization operator that approximates a low-order derivative. This paper proposes the use of orthogonal projections as regularization operators, e.g., with the same null space as commonly used finite difference operators. Applications to iterative and SVD-based methods for Tikhonov regularization are described. Truncated iterative and SVD methods are also considered.
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Research of L. Reichel was supported in part by an OBR Research Challenge Grant.
Research of F. Sgallari was supported in part by PRIN 2004 grant 2004014411-005.
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Morigi, S., Reichel, L. & Sgallari, F. Orthogonal projection regularization operators. Numer Algor 44, 99–114 (2007). https://doi.org/10.1007/s11075-007-9080-8
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DOI: https://doi.org/10.1007/s11075-007-9080-8