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In this paper, we propose an algorithmic framework, dubbed inertial alternating direction methods of multipliers (iADMM), for solving a class of nonconvex nonsmooth multiblock composite optimization problems with linear constraints. Our…

Optimization and Control · Mathematics 2023-01-26 Le Thi Khanh Hien , Duy Nhat Phan , Nicolas Gillis

Distributed cooperative localization in wireless networks is a challenging problem since it typically requires solving a large-scale nonconvex and nonsmooth optimization problem. In this paper, we reformulate the classic cooperative…

Optimization and Control · Mathematics 2023-08-08 Mei Zhang , Zhiguo Wang , Feng Yin , Xiaojing Shen

We develop a convex framework for spatially varying coefficient quantile regression that, for each predictor, separates a location-invariant \emph{global} effect from a \emph{spatial deviation}. An adaptive group penalty selects whether a…

Methodology · Statistics 2025-11-26 Hou Jian , Meng Tan , Tian Maozai

This paper presents a novel strategy for high-fidelity image restoration by characterizing both local smoothness and nonlocal self-similarity of natural images in a unified statistical manner. The main contributions are three-folds. First,…

Multimedia · Computer Science 2014-05-14 Jian Zhang , Debin Zhao , Ruiqin Xiong , Siwei Ma , Wen Gao

Ultrasound strain imaging, which delineates mechanical properties to detect tissue abnormalities, involves estimating the time-delay between two radio-frequency (RF) frames collected before and after tissue deformation. The existing…

Image and Video Processing · Electrical Eng. & Systems 2022-09-14 Md Ashikuzzaman , Hassan Rivaz

Using recent advances in generative artificial intelligence (AI) brought by diffusion models, this paper introduces a new synergistic method for spectral computed tomography (CT) reconstruction. Diffusion models define a neural network to…

We propose a new space-variant regularization term for variational image restoration based on the assumption that the gradient magnitudes of the target image distribute locally according to a half-Generalized Gaussian distribution. This…

Image and Video Processing · Electrical Eng. & Systems 2019-06-27 Alessandro Lanza , Serena Morigi , Monica Pragliola , Fiorella Sgallari

Removing optical and atmospheric blur from galaxy images significantly improves galaxy shape measurements for weak gravitational lensing and galaxy evolution studies. This ill-posed linear inverse problem is usually solved with…

Instrumentation and Methods for Astrophysics · Physics 2023-03-29 Tianao Li , Emma Alexander

Reconstructing images from downsampled and noisy measurements, such as MRI and low dose Computed Tomography (CT), is a mathematically ill-posed inverse problem. We propose an easy-to-use reconstruction method based on Expectation…

Image and Video Processing · Electrical Eng. & Systems 2022-08-29 Robert G. Aykroyd , Kehinde Olobatuyi

We propose a new method for computing Dynamic Mode Decomposition (DMD) evolution matrices, which we use to analyze dynamical systems. Unlike the majority of existing methods, our approach is based on a variational formulation consisting of…

Numerical Analysis · Mathematics 2019-05-24 Omri Azencot , Wotao Yin , Andrea Bertozzi

The alternating direction method of multipliers (ADMM) has been popular for solving many signal processing problems, convex or nonconvex. In this paper, we study an asynchronous implementation of the ADMM for solving a nonconvex nonsmooth…

Information Theory · Computer Science 2014-12-19 Mingyi Hong

Alternating direction method of multiplier (ADMM) is a popular method used to design distributed versions of a machine learning algorithm, whereby local computations are performed on local data with the output exchanged among neighbors in…

Machine Learning · Computer Science 2018-06-07 Xueru Zhang , Mohammad Mahdi Khalili , Mingyan Liu

Depth estimation is an essential component in understanding the 3D geometry of a scene, with numerous applications in urban and indoor settings. These scenes are characterized by a prevalence of human made structures, which in most of the…

Computer Vision and Pattern Recognition · Computer Science 2020-09-03 Mattia Rossi , Mireille El Gheche , Andreas Kuhn , Pascal Frossard

Image restoration is a typical ill-posed problem, and it contains various tasks. In the medical imaging field, an ill-posed image interrupts diagnosis and even following image processing. Both traditional iterative and up-to-date deep…

Image and Video Processing · Electrical Eng. & Systems 2021-02-12 Moran Xu , Dianlin Hu , Weifei Wu , Weiwen Wu

Since sparse unmixing has emerged as a promising approach to hyperspectral unmixing, some spatial-contextual information in the hyperspectral images has been exploited to improve the performance of the unmixing recently. The total variation…

Numerical Analysis · Computer Science 2020-07-14 Longfei Ren , Chengjing Wang , Peipei Tang , Zheng Ma

We propose an image deconvolution algorithm when the data is contaminated by Poisson noise. The image to restore is assumed to be sparsely represented in a dictionary of waveforms such as the wavelet or curvelet transforms. Our key…

Applications · Statistics 2009-11-13 François-Xavier Dupé , Jalal Fadili , Jean Luc Starck

Multi-block separable convex problems recently received considerable attention. This class of optimization problems minimizes a separable convex objective function with linear constraints. The algorithmic challenges come from the fact that…

Optimization and Control · Mathematics 2016-08-18 Qia Li , Yuesheng Xu , Na Zhang

We present two efficient numerical methods for susceptibility artifact correction applicable in Echo Planar Imaging (EPI), an ultra fast Magnetic Resonance Imaging (MRI) technique widely used in clinical applications. Both methods address a…

Optimization and Control · Mathematics 2016-11-23 Jan Macdonald , Lars Ruthotto

In this paper, we propose a new variational framework for 3D surface denoising over triangulated meshes, which is inspired by the success of semi-sparse regularization in image processing. Differing from the uniformly sampled image data,…

Computational Geometry · Computer Science 2025-10-16 Junqing Huang , Haihui Wang , Michael Ruzhansky

This paper considers the distributed optimization of a sum of locally observable, non-convex functions. The optimization is performed over a multi-agent networked system, and each local function depends only on a subset of the variables. An…

Optimization and Control · Mathematics 2016-05-04 Sandeep Kumar , Rahul Jain , Ketan Rajawat