15 citations · 40 across the 12 of their papers we have counts for
17 papers
On Optimal Regularization Parameters via Bilevel Learning
Matthias J. Ehrhardt, Silvia Gazzola, Sebastian J. Scott
Variational regularization is commonly used to solve linear inverse problems, and involves augmenting a data fidelity by a regularizer. The regularizer is used to promote a priori…
Symmetrization Techniques in Image Deblurring
Marco Donatelli, Paola Ferrari, Silvia Gazzola
This paper presents a couple of preconditioning techniques that can be used to enhance the performance of iterative regularization methods applied to image deblurring problems with…
Undersampling Raster Scans in Spectromicroscopy for reduced dose and faster measurements
Oliver Townsend, Silvia Gazzola, Sergey Dolgov +1
Combinations of spectroscopic analysis and microscopic techniques are used across many disciplines of scientific research, including material science, chemistry and biology. X-ray…
Automatic balancing parameter selection for Tikhonov-TV regularization
Ali Gholami, Silvia Gazzola
This paper considers large-scale linear ill-posed inverse problems whose solutions can be represented as sums of smooth and piecewise constant components. To solve such problems we…
Efficient learning methods for large-scale optimal inversion design
Julianne Chung, Matthias Chung, Silvia Gazzola +1
In this work, we investigate various approaches that use learning from training data to solve inverse problems, following a bi-level learning approach. We consider a general framew…
Efficient edge-preserving methods for dynamic inverse problems
Mirjeta Pasha, Arvind K. Saibaba, Silvia Gazzola +2
We consider efficient methods for computing solutions to dynamic inverse problems, where both the quantities of interest and the forward operator (measurement process) may change a…
Regularization by inexact Krylov methods with applications to blind deblurring
Silvia Gazzola, Malena Sabaté Landman
This paper is concerned with the regularization of large-scale discrete inverse problems by means of inexact Krylov methods. Specifically, we derive two new inexact Krylov methods…
Computational methods for large-scale inverse problems: a survey on hybrid projection methods
Julianne Chung, Silvia Gazzola
This paper surveys an important class of methods that combine iterative projection methods and variational regularization methods for large-scale inverse problems. Iterative method…
An Inner-Outer Iterative Method for Edge Preservation in Image Restoration and Reconstruction
Silvia Gazzola, Misha E. Kilmer, James G. Nagy +2
We present a new inner-outer iterative algorithm for edge enhancement in imaging problems. At each outer iteration, we formulate a Tikhonov-regularized problem where the penalizati…
Krylov Methods for Low-Rank Regularization
Silvia Gazzola, Chang Meng, James Nagy
This paper introduces new solvers for the computation of low-rank approximate solutions to large-scale linear problems, with a particular focus on the regularization of linear inve…
Adaptive Regularization Parameter Choice Rules for Large-Scale Problems
Silvia Gazzola, Malena Sabate 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 p…
Arnoldi decomposition, GMRES, and preconditioning for linear discrete ill-posed problems
Silvia Gazzola, Silvia Noschese, Paolo Novati +1
GMRES is one of the most popular iterative methods for the solution of large linear systems of equations that arise from the discretization of linear well-posed problems, such as D…
Flexible Krylov methods for regularization
Julianne Chung, Silvia Gazzola
In this paper we develop flexible Krylov methods for efficiently computing regularized solutions to large-scale linear inverse problems with an fit-to-data term and an $\e…
IR Tools: A MATLAB Package of Iterative Regularization Methods and Large-Scale Test Problems
Silvia Gazzola, Per Christian Hansen, James G. Nagy
This paper describes a new MATLAB software package of iterative regularization methods and test problems for large-scale linear inverse problems. The software package, called IR To…
Some transpose-free CG-like solvers for nonsymmetric ill-posed problems
Silvia Gazzola, Paolo Novati
This paper introduces and analyzes an original class of Krylov subspace methods that provide an efficient alternative to many well-known conjugate-gradient-like (CG-like) Krylov so…
Fast nonnegative least squares through flexible Krylov subspaces
Silvia Gazzola, Yves Wiaux
Constrained least squares problems arise in a variety of applications, and many iterative methods are already available to compute their solutions. This paper proposes a new effici…
Embedded techniques for choosing the parameter in Tikhonov regularization
Silvia Gazzola, Paolo Novati, Maria Rosaria Russo
This paper introduces a new strategy for setting the regularization parameter when solving large-scale discrete ill-posed linear problems by means of the Arnoldi-Tikhonov method. T…