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This paper presents a novel hybrid algorithm for minimizing the sum of a continuously differentiable loss function and a nonsmooth, possibly nonconvex, sparse regularization function. The proposed method alternates between solving a…

Optimization and Control · Mathematics 2025-04-01 Hao Wang , Xiangyu Yang , Yichen Zhu

Many problems in computational geometry are not stated in graph-theoretic terms, but can be solved efficiently by constructing an auxiliary graph and performing a graph-theoretic algorithm on it. Often, the efficiency of the algorithm…

Computational Geometry · Computer Science 2009-08-28 David Eppstein

Alternating least squares is the most widely used algorithm for CP tensor decomposition. However, alternating least squares may exhibit slow or no convergence, especially when high accuracy is required. An alternative approach is to regard…

Numerical Analysis · Mathematics 2020-06-11 Navjot Singh , Linjian Ma , Hongru Yang , Edgar Solomonik

A common way of partitioning graphs is through minimum cuts. One drawback of classical minimum cut methods is that they tend to produce small groups, which is why more balanced variants such as normalized and ratio cuts have seen more…

Machine Learning · Computer Science 2024-10-07 Chakib Fettal , Lazhar Labiod , Mohamed Nadif

This letter proposes a novel sparsity-aware adaptive filtering scheme and algorithms based on an alternating optimization strategy with shrinkage. The proposed scheme employs a two-stage structure that consists of an alternating…

Systems and Control · Computer Science 2023-07-19 Rodrigo C. de Lamare , Raimundo Sampaio-Neto

In many applications of tomography, the acquired projections are either limited in number or contain a significant amount of noise. In these cases, standard reconstruction methods tend to produce artifacts that can make further analysis…

Numerical Analysis · Mathematics 2016-04-11 D. M. Pelt , K. J. Batenburg

Wave equation techniques have been an integral part of geophysical imaging workflows to investigate the Earth's subsurface. Least-squares reverse time migration (LSRTM) is a linearized inversion problem that iteratively minimizes a misfit…

Computational Physics · Physics 2019-12-11 Janaki Vamaraju , Jeremy Vila , Mauricio Araya-Polo , Debanjan Datta , Mohamed Sidahmed , Mrinal Sen

This paper presents a solution for efficiently and accurately solving separable least squares problems with multiple datasets. These problems involve determining linear parameters that are specific to each dataset while ensuring that the…

Numerical Analysis · Mathematics 2024-04-23 Adelina Bärligea , Philipp Hochstaffl , Franz Schreier

Chance constrained program is computationally intractable due to the existence of chance constraints, which are randomly disturbed and should be satisfied with a probability. This paper proposes a two-layer randomized algorithm to address…

Optimization and Control · Mathematics 2019-11-11 Xun Shen , Jiancang Zhuang , Xingguo Zhang

Total variation (TV) is a widely used regularizer for stabilizing the solution of ill-posed inverse problems. In this paper, we propose a novel proximal-gradient algorithm for minimizing TV regularized least-squares cost functional. Our…

Information Theory · Computer Science 2016-01-05 Ulugbek S. Kamilov

The approximation of tensors has important applications in various disciplines, but it remains an extremely challenging task. It is well known that tensors of higher order can fail to have best low-rank approximations, but with an important…

Numerical Analysis · Mathematics 2015-03-19 Mike Espig , Aram Khachatryan

High radiation dose in CT scans increases a lifetime risk of cancer and has become a major clinical concern. Recently, iterative reconstruction algorithms with Total Variation (TV) regularization have been developed to reconstruct CT images…

Medical Physics · Physics 2015-05-19 Zhen Tian , Xun Jia , Kehong Yuan , Tinsu Pan , Steve B. Jiang

We consider adaptive system identification problems with convex constraints and propose a family of regularized Least-Mean-Square (LMS) algorithms. We show that with a properly selected regularization parameter the regularized LMS provably…

Methodology · Statistics 2010-12-24 Yilun Chen , Yuantao Gu , Alfred O. Hero

The conjugate gradient (CG) method is commonly used for the rapid solution of least squares problems. In image reconstruction, the problem can be ill-posed and also contaminated by noise; due to this, approaches such as regularization…

Optimization and Control · Mathematics 2018-02-14 Marcelo V. W. Zibetti , Chuan Lin , Gabor T. Herman

In this paper, we proposed an alternating projection based algorithm to solve a class of distributed MIN-MAX convex optimization problems. We firstly transform this MINMAX problem into the problem of searching for the minimum distance…

Systems and Control · Computer Science 2014-06-11 Chunhe Hu , Zongji Chen

In tomographic reconstruction, the goal is to reconstruct an unknown object from a collection of line integrals. Given a complete sampling of such line integrals for various angles and directions, explicit inverse formulas exist to…

Numerical Analysis · Mathematics 2018-01-18 Tristan van Leeuwen , Simon Maretzke , K. Joost Batenburg

This paper addresses the solution of inverse problems in imaging given an additional reference image. We combine a modification of the discrete geodesic path model for image metamorphosis with a variational model,actually the $L^2$-$TV$…

Numerical Analysis · Mathematics 2019-05-22 Sebastian Neumayer , Johannes Persch , Gabriele Steidl

We address the problem of solving mixed random linear equations. We have unlabeled observations coming from multiple linear regressions, and each observation corresponds to exactly one of the regression models. The goal is to learn the…

Machine Learning · Statistics 2020-08-13 Avishek Ghosh , Kannan Ramchandran

We propose new approximate alternating projection methods, based on randomized sketching, for the low-rank nonnegative matrix approximation problem: find a low-rank approximation of a nonnegative matrix that is nonnegative, but whose…

Numerical Analysis · Mathematics 2023-04-25 Sergey A. Matveev , Stanislav Budzinskiy

X-ray computed tomographic infrastructures are medical imaging modalities that rely on the acquisition of rays crossing examined objects while measuring their intensity decrease. Physical measurements are post-processed by mathematical…

Image and Video Processing · Electrical Eng. & Systems 2022-01-25 Attila Juhos
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