English
Related papers

Related papers: Variational Regularization of Inverse Problems for…

200 papers

During the inversion of discrete linear systems noise in data can be amplified and result in meaningless solutions. To combat this effect, characteristics of solutions that are considered desirable are mathematically implemented during…

Numerical Analysis · Mathematics 2023-02-07 Michael J. Byrne , Rosemary A. Renaut

We propose a regularization method to solve a nonlinear ill-posed problem connected to inversion of data gathered by a ground conductivity meter.

Numerical Analysis · Mathematics 2021-09-21 Gian Piero Deidda , Caterina Fenu , Giuseppe Rodriguez

This article is the second work in our series of papers dedicated to image processing models based on the fractional order total variation $TV^r$. In our first work of this series, we studied key analytic properties of these semi-norms.…

Optimization and Control · Mathematics 2019-03-21 Pan Liu , Xin Yang Lu

In this paper, we propose Total Variation Regularized Tensor-on-scalar Regression(TVTR), a novel method for estimating the association between a tensor outcome (a one dimensional or multidimensional array) and scalar predictors. While the…

Methodology · Statistics 2018-12-11 Ying Liu , Bowei Yan , Kathleen Merikangas , Haochang Shou

The goal of this paper is to further develop an approach to inverse problems with imperfect forward operators that is based on partially ordered spaces. Studying the dual problem yields useful insights into the convergence of the…

Numerical Analysis · Mathematics 2019-01-30 Martin Burger , Yury Korolev , Julian Rasch

Frequency-domain electromagnetic instruments allow the collection of data in different configurations, that is, varying the intercoil spacing, the frequency, and the height above the ground. Their handy size makes these tools very practical…

Numerical Analysis · Mathematics 2021-09-21 Gian Piero Deidda , Patricia Diaz de Alba , Giuseppe Rodriguez , Giulio Vignoli

Lifting methods allow to transform hard variational problems such as segmentation and optical flow estimation into convex problems in a suitable higher-dimensional space. The lifted models can then be efficiently solved to a global optimum,…

Numerical Analysis · Mathematics 2019-08-13 Thomas Vogt , Evgeny Strekalovskiy , Daniel Cremers , Jan Lellmann

Several generalizations of the traditional Tikhonov-Phillips regularization method have been proposed during the last two decades. Many of these generalizations are based upon inducing stability throughout the use of different penalizers…

Functional Analysis · Mathematics 2014-03-25 Gisela L. Mazzieri , Ruben D. Spies , Karina G. Temperini

Even though the statistical theory of linear inverse problems is a well-studied topic, certain relevant cases remain open. Among these is the estimation of functions of bounded variation ($BV$), meaning $L^1$ functions on a $d$-dimensional…

Statistics Theory · Mathematics 2019-05-22 Miguel del Álamo , Axel Munk

Regular variation of distributional tails is known to be preserved by various linear transformations of some random structures. An inverse problem for regular variation aims at understanding whether the regular variation of a transformed…

Probability · Mathematics 2014-01-23 Ewa Damek , Thomas Mikosch , Jan Rosinski , Gennady Samorodnitsky

In data-driven inverse optimization an observer aims to learn the preferences of an agent who solves a parametric optimization problem depending on an exogenous signal. Thus, the observer seeks the agent's objective function that best…

Optimization and Control · Mathematics 2017-07-25 Peyman Mohajerin Esfahani , Soroosh Shafieezadeh-Abadeh , Grani Adiwena Hanasusanto , Daniel Kuhn

We propose a variational regularisation approach for the problem of template-based image reconstruction from indirect, noisy measurements as given, for instance, in X-ray computed tomography. An image is reconstructed from such measurements…

Optimization and Control · Mathematics 2019-04-02 Lukas F. Lang , Sebastian Neumayer , Ozan Öktem , Carola-Bibiane Schönlieb

A Transformer-based deep direct sampling method is proposed for electrical impedance tomography, a well-known severely ill-posed nonlinear boundary value inverse problem. A real-time reconstruction is achieved by evaluating the learned…

Machine Learning · Computer Science 2023-03-07 Ruchi Guo , Shuhao Cao , Long Chen

We consider a bilevel optimisation approach for parameter learning in higher-order total variation image reconstruction models. Apart from the least squares cost functional, naturally used in bilevel learning, we propose and analyse an…

Optimization and Control · Mathematics 2020-02-13 J. C. De los Reyes , C. -B. Schönlieb , T. Valkonen

We introduce a general framework for the reconstruction of periodic multivariate functions from finitely many and possibly noisy linear measurements. The reconstruction task is formulated as a penalized convex optimization problem, taking…

Optimization and Control · Mathematics 2020-12-02 Julien Fageot , Matthieu Simeoni

Inverse problems are inherently ill-posed and therefore require regularization techniques to achieve a stable solution. While traditional variational methods have well-established theoretical foundations, recent advances in machine learning…

Numerical Analysis · Mathematics 2023-09-15 Simon Göppel , Jürgen Frikel , Markus Haltmeier

The concept of deep learning is employed for the inversion of NMR signals and it is shown that NMR signal inversion can be considered as an image-to-image regression problem, which can be treated with a convolutional neural net. It is…

Chemical Physics · Physics 2023-11-27 Julian B. B. Beckmann , Mick D. Mantle , Andrew J. Sederman , Lynn F. Gladden

It is common to have to process signals or images whose values are cyclic and can be represented as points on the complex circle, like wrapped phases, angles, orientations, or color hues. We consider a Tikhonov-type regularization model to…

Optimization and Control · Mathematics 2022-06-08 Laurent Condat

Distributions measured in high energy physics experiments are usually distorted and/or transformed by various detector effects. A regularization method for unfolding these distributions is re-formulated in terms of the Singular Value…

High Energy Physics - Phenomenology · Physics 2008-11-26 Andreas Hoecker , Vakhtang Kartvelishvili

Extrinsic Gaussian process regression methods, such as wrapped Gaussian process, have been developed to analyze manifold data. However, there is a lack of intrinsic Gaussian process methods for studying complex data with manifold-valued…

Machine Learning · Statistics 2025-02-11 Zhanfeng Wang , Xinyu Li , Hao Ding , Jian Qing Shi