Pivoted Cauchy-Like Preconditioners for Regularized Solution of Ill-Posed Problems
نویسندگان
چکیده
منابع مشابه
Pivoted Cauchy-Like Preconditioners for Regularized Solution of Ill-Posed Problems
Many ill-posed problems are solved using a discretization that results in a least squares problem or a linear system involving a Toeplitz matrix. The exact solution to such problems is often hopelessly contaminated by noise, since the discretized problem is quite ill conditioned, and noise components in the approximate null-space dominate the solution vector. Therefore we seek an approximate so...
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Ill-conditioned matrices with block Toeplitz, Toeplitz block (BTTB) structure arise from the discretization of certain ill-posed problems in signal and image processing. We use a preconditioned conjugate gradient algorithm to compute a regularized solution to this linear system given noisy data. Our preconditioner is a Cauchy-like block diagonal approximation to an orthogonal transformation of ...
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ژورنال
عنوان ژورنال: SIAM Journal on Scientific Computing
سال: 1999
ISSN: 1064-8275,1095-7197
DOI: 10.1137/s1064827596308974