English
Related papers

Related papers: Convergence Rates for Exponentially Ill-Posed Inve…

200 papers

In this paper we introduce the class of infinite infimal convolution functionals and apply these functionals to the regularization of ill-posed inverse problems. The proposed regularization involves an infimal convolution of a continuously…

Optimization and Control · Mathematics 2024-12-17 Kristian Bredies , Marcello Carioni , Martin Holler , Yury Korolev , Carola-Bibiane Schönlieb

The convergence rates results in $\ell^1$-regularization when the sparsity assumption is narrowly missed, presented by Burger et al. (2013 Inverse Problems 29 025013), are based on a crucial condition which requires that all basis elements…

Numerical Analysis · Mathematics 2015-08-05 Stephan W. Anzengruber , Bernd Hofmann , Ronny Ramlau

This work is concerned with linear inverse problems where a distributed parameter is known a priori to only take on values from a given discrete set. This property can be promoted in Tikhonov regularization with the aid of a suitable convex…

Optimization and Control · Mathematics 2018-04-19 Christian Clason , Thi Bich Tram Do

An ill-posed inverse problem of autoconvolution type is investigated. This inverse problem occurs in nonlinear optics in the context of ultrashort laser pulse characterization. The novelty of the mathematical model consists in a physically…

Mathematical Physics · Physics 2013-01-28 Daniel Gerth , Bernd Hofmann , Simon Birkholz , Sebastian Koke , Günter Steinmeyer

We study Tikhonov regularization for solving ill--posed operator equations where the solutions are functions defined on surfaces. One contribution of this paper is an error analysis of Tikhonov regularization which takes into account…

Numerical Analysis · Mathematics 2016-12-15 Guozhi Dong , Bert Juettler , Otmar Scherzer , Thomas Takacs

In a separable Hilbert space, we study the minimization problem of a convex smooth function with Lipschitz continuous gradient whose evaluations are corrupted by random noise. To this end, we associate a stochastic inertial system that…

Optimization and Control · Mathematics 2025-12-18 Chiara Schindler

Ill-posed linear inverse problems appear frequently in various signal processing applications. It can be very useful to have theoretical characterizations that quantify the level of ill-posedness for a given inverse problem and the degree…

Signal Processing · Electrical Eng. & Systems 2023-04-26 Justin P. Haldar

We consider the stable approximation of sparse solutions to non-linear operator equations by means of Tikhonov regularization with a subquadratic penalty term. Imposing certain assumptions, which for a linear operator are equivalent to the…

Functional Analysis · Mathematics 2009-12-06 Markus Grasmair , Markus Haltmeier , Otmar Scherzer

We exploit the similarities between Tikhonov regularization and Bayesian hierarchical models to propose a regularization scheme that acts like a distributed Tikhonov regularization where the amount of regularization varies from component to…

Numerical Analysis · Mathematics 2024-04-10 Daniela Calvetti , Erkki Somersalo

Blind inverse problems arise in many experimental settings where both the signal of interest and the forward operator are (partially) unknown. In this context, methods developed for the non-blind case cannot be adapted in a straightforward…

Machine Learning · Computer Science 2026-04-21 Nathan Buskulic , Luca Calatroni , Lorenzo Rosasco , Silvia Villa

We study the Tikhonov regularization for ill-posed non-linear operator equations in Hilbert scales. Our focus is on the interplay between the smoothness-promoting properties of the penalty and the smoothness inherent in the solution. The…

Numerical Analysis · Mathematics 2018-01-17 Bernd Hofmann , Peter Mathé

In this paper, we investigate an inverse random source problem concerned with recovering the strength of a random, uncorrelated acoustic source from correlation measurements of emitted time-harmonic acoustic waves. Such problems arise in…

Numerical Analysis · Mathematics 2026-02-25 Philipp Mickan , Thorsten Hohage

Recent advances in machine learning have inspired a surge of research into reconstructing specific quantities of interest from measurements that comply with certain physical laws. These efforts focus on inverse problems that are governed by…

Machine Learning · Statistics 2025-04-23 Honam Wong , Wendao Wu , Fanghui Liu , Yiping Lu

In this paper, we study the Tikhonov regularization scheme in Hilbert scales for the nonlinear statistical inverse problem with a general noise. The regularizing norm in this scheme is stronger than the norm in Hilbert space. We focus on…

Statistics Theory · Mathematics 2024-04-09 Abhishake Rastogi

We study the application of Tikhonov regularization to ill-posed nonlinear operator equations. The objective of this work is to prove low order convergence rates for the discrepancy principle under low order source conditions of logarithmic…

Numerical Analysis · Mathematics 2023-05-02 Chantal Klinkhammer , Robert Plato

Tikhonov regularization is studied in the case of linear pseudodifferential operator as the forward map and additive white Gaussian noise as the measurement error. The measurement model for an unknown function $u(x)$ is \begin{eqnarray*}…

Analysis of PDEs · Mathematics 2016-06-03 Hanne Kekkonen , Matti Lassas , Samuli Siltanen

A main drawback of classical Tikhonov regularization is that often the parameters required to apply theoretical results, e.g., the smoothness of the sought-after solution and the noise level, are unknown in practice. In this paper we…

Numerical Analysis · Mathematics 2021-01-01 Daniel Gerth , Ronny Ramlau

So-called functional error estimators provide a valuable tool for reliably estimating the discretization error for a sum of two convex functions. We apply this concept to Tikhonov regularization for the solution of inverse problems for…

Numerical Analysis · Mathematics 2017-02-13 Christian Clason , Barbara Kaltenbacher , Daniel Wachsmuth

In this work we study the inverse boundary value problem of determining the refractive index in the acoustic equation. It is known that this inverse problem is ill-posed. Nonetheless, we show that the ill-posedness decreases when we…

Analysis of PDEs · Mathematics 2011-10-25 Sei Nagayasu , Gunther Uhlmann , Jenn-Nan Wang

Tikhonov regularization with square-norm penalty for linear forward operators has been studied extensively in the literature. However, the results on convergence theory are based on technical proofs and difficult to interpret. It is also…

Numerical Analysis · Mathematics 2021-07-07 Daniel Gerth