English
Related papers

Related papers: Some Results on the Regularization of LSQR for Lar…

200 papers

In this study, we introduce two new Krylov subspace methods for solving rectangular large-scale linear inverse problems. The first approach is a modification of the Hessenberg iterative algorithm that is based off an LU factorization and is…

Numerical Analysis · Mathematics 2024-09-10 Ariana N. Brown , Julianne Chung , James G. Nagy , Malena Sabaté Landman

This paper derives a new class of adaptive regularization parameter choice strategies that can be effectively and efficiently applied when regularizing large-scale linear inverse problems by combining standard Tikhonov regularization and…

Numerical Analysis · Mathematics 2019-07-15 Silvia Gazzola , Malena Sabate Landman

Krylov subspace methods for solving linear systems of equations involving skew-symmetric matrices have gained recent attention. Numerical equivalences among Krylov subspace methods for nonsingular skew-symmetric linear systems have been…

Numerical Analysis · Mathematics 2023-08-01 Kui Du , Jia-Jun Fan , Xiao-Hui Sun , Fang Wang , Ya-Lan Zhang

Tikhonov regularization is a widely used technique in solving inverse problems that can enforce prior properties on the desired solution. In this paper, we propose a Krylov subspace based iterative method for solving linear inverse problems…

Numerical Analysis · Mathematics 2023-08-15 Haibo Li

In this paper, we apply randomized algorithms to approximate the total least squares (TLS) solution of the problem $Ax\approx b$ in the large-scale discrete ill-posed problems. A regularization technique, based on the multiplicative…

Numerical Analysis · Mathematics 2018-08-09 Liping Zhang , Yimin Wei

We study the application of the Augmented Lagrangian Method to the solution of linear ill-posed problems. Previously, linear convergence rates with respect to the Bregman distance have been derived under the classical assumption of a…

Numerical Analysis · Mathematics 2015-06-04 Klaus Frick , Markus Grasmair

In this work we consider the stable numerical solution of large-scale ill-posed nonlinear least squares problems with nonzero residual. We propose a non-stationary Tikhonov method with inexact step computation, specially designed for…

Optimization and Control · Mathematics 2020-01-03 Stefania Bellavia , Marco Donatelli , Elisa Riccietti

In recent work (Maierhofer & Huybrechs, 2022, Adv. Comput. Math.), the authors showed that least-squares oversampling can improve the convergence properties of collocation methods for boundary integral equations involving operators of…

Numerical Analysis · Mathematics 2022-01-28 Georg Maierhofer , Daan Huybrechs

We propose inexact subspace iteration for solving high-dimensional eigenvalue problems with low-rank structure. Inexactness stems from low-rank compression, enabling efficient representation of high-dimensional vectors in a low-rank tensor…

Numerical Analysis · Mathematics 2025-10-16 Alec Dektor , Peter DelMastro , Erika Ye , Roel Van Beeumen , Chao Yang

Currently, existing tensor recovery methods fail to recognize the impact of tensor scale variations on their structural characteristics. Furthermore, existing studies face prohibitive computational costs when dealing with large-scale…

Machine Learning · Computer Science 2025-07-09 Wenjin Qin , Hailin Wang , Jingyao Hou , Jianjun Wang

Randomized subspace embedding methods have had a great impact on the solution of a linear least squares (LS) problem by reducing its row dimension, leading to a randomized or sketched LS (sLS) problem, and use the solution of the sLS…

Numerical Analysis · Mathematics 2026-02-12 Zhongxiao Jia , Xinyuan Wan

Many applications in science and engineering require the solution of large linear discrete ill-posed problems that are obtained by the discretization of a Fredholm integral equation of the first kind in several space-dimensions. The matrix…

Numerical Analysis · Mathematics 2017-05-19 Laura Dykes , Guangxin Huang , Silvia Noschese , Lothar Reichel

This paper introduces new solvers for efficiently computing solutions to large-scale inverse problems with group sparsity regularization, including both non-overlapping and overlapping groups. Group sparsity regularization refers to a type…

Numerical Analysis · Mathematics 2023-06-16 Julianne Chung , Malena Sabaté Landman

This paper provides a new regularization method which is particularly suitable for linear exponentially ill-posed problems. Under logarithmic source conditions (which have a natural interpretation in terms of Sobolev spaces in the…

Numerical Analysis · Mathematics 2020-07-08 Walter Cedric Simo Tao Lee

The computation of sparse solutions of large-scale linear discrete ill-posed problems remains a computationally demanding task. A powerful framework in this context is the use of iteratively reweighted schemes, which are based on…

Numerical Analysis · Mathematics 2025-10-14 Malena Sabaté Landman , Yuji Nakatsukasa

Inverse scattering has a broad applicability in quantum mechanics, remote sensing, geophysical, and medical imaging. This paper presents a robust direct reduced order model (ROM) method for solving inverse scattering problems based on an…

Numerical Analysis · Mathematics 2023-11-29 Justin Baker , Elena Cherkaev , Vladimir Druskin , Shari Moskow , Mikhail Zaslavsky

Recently, inverse problems have attracted more and more attention in computational mathematics and become increasingly important in engineering applications. After the discretization, many of inverse problems are reduced to linear systems.…

Numerical Analysis · Mathematics 2022-04-07 Gong Rongfang , Huang Qin

Total least squares (TLS) is an effective method for solving linear equations with the situations, when noise is not just in observation matrices but also in mapping matrices. Moreover, the Tikhonov regularization is widely used in plenty…

Numerical Analysis · Mathematics 2022-11-14 F. Han , Y. Wei , P. Xie

This work considers large-scale Lyapunov matrix equations of the form $AX + XA = \boldsymbol{c}\boldsymbol{c}^T$, where $A$ is a symmetric positive definite matrix and $\boldsymbol{c}$ is a vector. Motivated by the need to solve such…

Numerical Analysis · Mathematics 2025-05-29 Angelo A. Casulli , Francesco Hrobat , Daniel Kressner

In the present work, we propose new tensor Krylov subspace method for ill posed linear tensor problems such as in color or video image restoration. Those methods are based on the tensor-tensor discrete cosine transform that gives fast…

Numerical Analysis · Mathematics 2021-03-23 M. El Guide , A. El Ichi , K. Jbilou