Enriched Krylov subspace methods for ill-posed problems
If a linear system is ill-posed, there may be a few eigenvectors with small eigenvalues. Krylov subspace methods are accelerated if directions are added that model the directions of those eigenvectors. The resulting matrices are low rank updates of matrices that are found in standard Krylov space methods. Detailed numerical examples conclude the paper.
scientific article; zbMATH DE number 1880080