English
Related papers

Related papers: Scalable splitting algorithms for big-data interfe…

200 papers

We describe a "spatio-spectral" deconvolution algorithm for wide-band imaging in radio interferometry. In contrast with the existing multi-frequency reconstruction algorithms, the proposed method does not rely on a model of the…

Instrumentation and Methods for Astrophysics · Physics 2016-03-01 André Ferrari , Jérémy Deguignet , Chiara Ferrari , David Mary , Antony Schutz , Oleg Smirnov

Our work considers the optimization of the sum of a non-smooth convex function and a finite family of composite convex functions, each one of which is composed of a convex function and a bounded linear operator. This type of problem is…

Optimization and Control · Mathematics 2019-08-30 Yu-Chao Tang , Chuan-Xi Zhu , Meng Wen , Ji-Gen Peng

The paper considers the minimization of a separable convex function subject to linear ascending constraints. The problem arises as the core optimization in several resource allocation scenarios, and is a special case of an optimization of a…

Optimization and Control · Mathematics 2016-08-30 Akhil P T , Rajesh Sundaresan

We present a supervised hyperspectral image segmentation algorithm based on a convex formulation of a marginal maximum a posteriori segmentation with hidden fields and structure tensor regularization: Segmentation via the Constraint Split…

Computer Vision and Pattern Recognition · Computer Science 2015-04-28 Filipe Condessa , Jose Bioucas-Dias , Jelena Kovacevic

In Part I of this paper, we proposed and analyzed a novel algorithmic framework for the minimization of a nonconvex (smooth) objective function, subject to nonconvex constraints, based on inner convex approximations. This Part II is devoted…

Information Theory · Computer Science 2017-04-05 Gesualdo Scutari , Francisco Facchinei , Lorenzo Lampariello , Peiran Song , Stefania Sardellitti

The Square Kilometre Array (SKA) will form the largest radio telescope ever built and such a huge instrument in the desert poses enormous engineering and logistic challenges. Algorithmic and architectural breakthroughs are needed. Data is…

Instrumentation and Methods for Astrophysics · Physics 2014-11-17 Orhan Ocal , Paul Hurley , Giovanni Cherubini , Sanaz Kazemi

In recent years, deep learning has been successfully applied in various scientific domains. Following these promising results and performances, it has recently also started being evaluated in the domain of radio astronomy. In particular,…

The paper reviews progress in imaging in radio interferometry for the period 1993-1996. Unlike an optical telescope, the basic measurements of a radio interferometer (correlations between antennas) are indirectly related to a sky brightness…

Astrophysics · Physics 2007-05-23 R. J. Sault , T. A. Oosterloo

Next generation radio observatories such as the MWA, LWA, LOFAR, CARMA and SKA provide a number of challenges for interferometric data analysis. These challenges include heterogeneous arrays, direction-dependent instrumental gain, and…

Astrophysics · Physics 2015-05-13 Miguel F. Morales , Michael Matejek

Majorization-minimization algorithms consist of iteratively minimizing a majorizing surrogate of an objective function. Because of its simplicity and its wide applicability, this principle has been very popular in statistics and in signal…

Machine Learning · Statistics 2013-09-11 Julien Mairal

Modern radio telescopes, such as the Square Kilometre Array (SKA), will probe the radio sky over large fields-of-view, which results in large w-modulations of the sky image. This effect complicates the relationship between the measured…

Instrumentation and Methods for Astrophysics · Physics 2017-07-14 Arwa Dabbech , Laura Wolz , Luke Pratley , Jason D. McEwen , Yves Wiaux

This paper describes the Conic Operator Splitting Method (COSMO) solver, an operator splitting algorithm for convex optimisation problems with quadratic objective function and conic constraints. At each step the algorithm alternates between…

Optimization and Control · Mathematics 2021-08-31 Michael Garstka , Mark Cannon , Paul Goulart

At present, and increasingly so in the future, much of the captured visual content will not be seen by humans. Instead, it will be used for automated machine vision analytics and may require occasional human viewing. Examples of such…

Image and Video Processing · Electrical Eng. & Systems 2022-04-13 Hyomin Choi , Ivan V. Bajic

The short-spacing problem describes the inherent inability of radio-interferometric arrays to measure the integrated flux and structure of diffuse emission associated with extended sources. New interferometric arrays, such as SKA, require…

Instrumentation and Methods for Astrophysics · Physics 2018-07-18 S. Faridani , F. Bigiel , L. Floeer , J. Kerp , S. Stanimirovic

Predictive models can be used on high-dimensional brain images for diagnosis of a clinical condition. Spatial regularization through structured sparsity offers new perspectives in this context and reduces the risk of overfitting the model…

Computation of the large sparse matrix exponential has been an important topic in many fields, such as network and finite-element analysis. The existing scaling and squaring algorithm (SSA) is not suitable for the computation of the large…

Numerical Analysis · Mathematics 2021-10-12 Feng Wu , Kailing Zhang , Li Zhu , Jiayao Hu

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,…

Numerical Analysis · Mathematics 2024-12-19 Matthias J. Ehrhardt , Zeljko Kereta , Jingwei Liang , Junqi Tang

Recently, sparsity-based algorithms are proposed for super-resolution spectrum estimation. However, to achieve adequately high resolution in real-world signal analysis, the dictionary atoms have to be close to each other in frequency,…

Machine Learning · Statistics 2015-06-05 Yiyuan She , Huanghuang Li , Jiangping Wang , Dapeng Wu

We present an algorithm for creating high resolution anatomically plausible images consistent with acquired clinical brain MRI scans with large inter-slice spacing. Although large data sets of clinical images contain a wealth of…

Computer Vision and Pattern Recognition · Computer Science 2019-03-14 Adrian V. Dalca , Katherine L. Bouman , William T. Freeman , Natalia S. Rost , Mert R. Sabuncu , Polina Golland

Reconstructing high-quality magnetic resonance images (MRI) from undersampled raw data is of great interest from both technical and clinical point of views. To this date, however, it is still a mathematically and computationally challenging…

Numerical Analysis · Mathematics 2021-09-01 T. Schmoderer , A. I Aviles-Rivero , V. Corona , N. Debroux , C-B. Schönlieb