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相关论文: Pinsker estimators for local helioseismology

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In imaging modalities recording diffraction data, the original image can be reconstructed assuming known phases. When phases are unknown, oversampling and a constraint on the support region in the original object can be used to solve a…

信号处理 · 电气工程与系统科学 2018-10-17 Alberto Pietrini , Carl Nettelblad

A challenge in high-dimensional inverse problems is developing iterative solvers to find the accurate solution of regularized optimization problems with low computational cost. An important example is computed tomography (CT) where both…

数值分析 · 数学 2024-12-16 Alessandro Perelli , Carola-Bibiane Schonlieb , Matthias J. Ehrhardt

Statistical inverse learning aims at recovering an unknown function $f$ from randomly scattered and possibly noisy point evaluations of another function $g$, connected to $f$ via an ill-posed mathematical model. In this paper we blend…

统计理论 · 数学 2024-01-22 Tapio Helin

Stochastic optimisation algorithms are the de facto standard for machine learning with large amounts of data. Handling only a subset of available data in each optimisation step dramatically reduces the per-iteration computational costs,…

数值分析 · 数学 2024-12-19 Matthias J. Ehrhardt , Zeljko Kereta , Jingwei Liang , Junqi Tang

Inverse problems in physical or biological sciences often involve recovering an unknown parameter that is random. The sought-after quantity is a probability distribution of the unknown parameter, that produces data that aligns with…

机器学习 · 统计学 2024-10-02 Qin Li , Maria Oprea , Li Wang , Yunan Yang

We consider a stochastic version of the proximal point algorithm for optimization problems posed on a Hilbert space. A typical application of this is supervised learning. While the method is not new, it has not been extensively analyzed in…

最优化与控制 · 数学 2021-09-28 Monika Eisenmann , Tony Stillfjord , Måns Williamson

Many practical imaging systems suffer from uncertainty in acquisition geometry -- such as projection angles in computed tomography or sensor positions in photoacoustic tomography -- leading to nonlinear inverse problems that require joint…

数值分析 · 数学 2026-05-08 Toluwani Okunola , Mirjeta Pasha , Misha E. Kilmer , James G. Nagy , Eric de Sturler

We propose a new randomized algorithm for solving convex optimization problems that have a large number of constraints (with high probability). Existing methods like interior-point or Newton-type algorithms are hard to apply to such…

最优化与控制 · 数学 2020-03-25 Bo Wei , William B. Haskell , Sixiang Zhao

Numerical integral operators of convolution type form the basis of most wave-equation-based methods for processing and imaging of seismic data. As several of these methods require the solution of an inverse problem, multiple forward and…

地球物理 · 物理学 2020-11-24 Matteo Ravasi , Ivan Vasconcelos

We consider the inverse scattering problem for time-harmonic acoustic waves in a medium with pointwise inhomogeneities. In the Foldy-Lax model, the estimation of the scatterers' locations and intensities from far field measurements can be…

数值分析 · 数学 2024-07-25 Giovanni S. Alberti , Romain Petit , Matteo Santacesaria

Phase retrieval is in general a non-convex and non-linear task and the corresponding algorithms struggle with the issue of local minima. We consider the case where the measurement samples within typically very small and disconnected subsets…

信号处理 · 电气工程与系统科学 2022-06-28 Jonas Kornprobst , Alexander Paulus , Josef Knapp , Thomas F. Eibert

We present an adaptive regularization scheme for optimizing composite energy functionals arising in image analysis problems. The scheme automatically trades off data fidelity and regularization depending on the current data fit during the…

计算机视觉与模式识别 · 计算机科学 2017-05-10 Byung-Woo Hong , Ja-Keoung Koo , Martin Burger , Stefano Soatto

Local helioseismology has so far relied on semi-analytical methods to compute the spatial sensitivity of wave travel times to perturbations in the solar interior. These methods are cumbersome and lack flexibility. Here we propose a…

A new strategy based on numerical homogenization and Bayesian techniques for solving multiscale inverse problems is introduced. We consider a class of elliptic problems which vary at a microscopic scale, and we aim at recovering the highly…

数值分析 · 数学 2018-07-30 Assyr Abdulle , Andrea Di Blasio

This paper introduces a novel variational Bayesian method that integrates Tucker decomposition for efficient high-dimensional inverse problem solving. The method reduces computational complexity by transforming variational inference from a…

机器学习 · 计算机科学 2026-03-18 Qing-Mei Yang , Da-Qing Zhang

Given a proper convex lower semicontinuous function defined on a Hilbert space and whose solution set is supposed nonempty. For attaining a global minimizer when this convex function is continuously differentiable, we approach it by a…

最优化与控制 · 数学 2024-04-02 A. C. Bagy , Z. Chbani , H. Riahi

Principal component analysis (PCA) is known to be sensitive to outliers, so that various robust PCA variants were proposed in the literature. A recent model, called REAPER, aims to find the principal components by solving a convex…

数值分析 · 数学 2021-03-19 Robert Beinert , Gabriele Steidl

In many linear inverse problems, we want to estimate an unknown vector belonging to a high-dimensional (or infinite-dimensional) space from few linear measurements. To overcome the ill-posed nature of such problems, we use a low-dimension…

信息论 · 计算机科学 2017-07-18 Yann Traonmilin , Gilles Puy , Rémi Gribonval , Mike Davies

We consider the problem of discrete-time signal denoising, focusing on a specific family of non-linear convolution-type estimators. Each such estimator is associated with a time-invariant filter which is obtained adaptively, by solving a…

统计理论 · 数学 2018-06-13 Dmitrii Ostrovskii , Zaid Harchaoui

Many inverse problems include nuisance parameters which, while not of direct interest, are required to recover primary parameters. Structure present in these problems allows efficient optimization strategies - a well known example is…

数值分析 · 数学 2015-06-05 Aleksandr Y. Aravkin , Tristan van Leeuwen