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Related papers: Greedy techniques for inverse problems

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We study a linear quadratic regulation problem with a constraint where the control input can be nonzero only at a limited number of times. Given that this constraint leads to a combinational optimization problem, we adopt a greedy method to…

Systems and Control · Electrical Eng. & Systems 2024-03-26 Shumpei Nishida , Kunihisa Okano

We propose an active 3D mapping method for depth sensors, which allow individual control of depth-measuring rays, such as the newly emerging solid-state lidars. The method simultaneously (i) learns to reconstruct a dense 3D occupancy map…

Computer Vision and Pattern Recognition · Computer Science 2017-08-08 Karel Zimmermann , Tomas Petricek , Vojtech Salansky , Tomas Svoboda

We consider the optimal coverage problem where a multi-agent network is deployed in an environment with obstacles to maximize a joint event detection probability. The objective function of this problem is non-convex and no global optimum is…

Optimization and Control · Mathematics 2017-08-15 Xinmiao Sun , Christos G. Cassandras , Xiangyu Meng

In this paper we introduce several extremal sequences of points on locally compact metric spaces and study their asymptotic properties. These sequences are defined through a greedy algorithm by minimizing a certain energy functional whose…

Mathematical Physics · Physics 2019-10-22 A. López García

Tomographic imaging is in general an ill-posed inverse problem. Typically, a single regularized image estimate of the sought-after object is obtained from tomographic measurements. However, there may be multiple objects that are all…

Image and Video Processing · Electrical Eng. & Systems 2022-07-28 Sayantan Bhadra , Umberto Villa , Mark A. Anastasio

We show the potential of greedy recovery strategies for the sparse approximation of multivariate functions from a small dataset of pointwise evaluations by considering an extension of the orthogonal matching pursuit to the setting of…

Numerical Analysis · Mathematics 2019-05-06 Ben Adcock , Simone Brugiapaglia

This paper is devoted to the development and convergence analysis of greedy reconstruction algorithms based on the strategy presented in [Y. Maday and J. Salomon, Joint Proceedings of the 48th IEEE Conference on Decision and Control and the…

Optimization and Control · Mathematics 2023-08-30 S. Buchwald , G. Ciaramella , J. Salomon

The multi-step inertial randomized Kaczmarz (MIRK) method is an iterative method for solving large-scale linear systems. In this paper, we enhance the MIRK method by incorporating the greedy probability criterion, coupled with the…

Numerical Analysis · Mathematics 2024-10-10 Yansheng Su , Deren Han , Yun Zeng , Jiaxin Xie

When developing robust preconditioners for multiphysics problems, fractional functions of the Laplace operator often arise and need to be inverted. Rational approximation in the uniform norm can be used to convert inverting those fractional…

Numerical Analysis · Mathematics 2024-07-23 James H. Adler , Xiaozhe Hu , Xue Wang , Zhongqin Xue

We address an optimal sensor placement problem through Bayesian experimental design for seismic full waveform inversion for the recovery of the associated moment tensor. The objective is that of optimally choosing the location of the…

MapReduce has become the de facto standard model for designing distributed algorithms to process big data on a cluster. There has been considerable research on designing efficient MapReduce algorithms for clustering, graph optimization, and…

Data Structures and Algorithms · Computer Science 2018-06-19 Nicholas J. A. Harvey , Christopher Liaw , Paul Liu

We present a fast two-phase algorithm for super-resolution with strong theoretical guarantees. Given the low-frequency part of the spectrum of a sequence of impulses, Phase I consists of a greedy algorithm that roughly estimates the impulse…

Information Theory · Computer Science 2015-11-12 Armin Eftekhari , Michael B. Wakin

In this paper we consider the solution of certain convex integer minimization problems via greedy augmentation procedures. We show that a greedy augmentation procedure that employs only directions from certain Graver bases needs only…

Optimization and Control · Mathematics 2011-01-19 Raymond Hemmecke , Shmuel Onn , Robert Weismantel

Maximum Inner Product Search (MIPS) is an important task in many machine learning applications such as the prediction phase of a low-rank matrix factorization model for a recommender system. There have been some works on how to perform MIPS…

Data Structures and Algorithms · Computer Science 2016-10-12 Hsiang-Fu Yu , Cho-Jui Hsieh , Qi Lei , Inderjit S. Dhillon

We study greedy-type algorithms such that at a greedy step we pick several dictionary elements contrary to a single dictionary element in standard greedy-type algorithms. We call such greedy algorithms {\it super greedy algorithms}. The…

Numerical Analysis · Mathematics 2010-10-27 Entao Liu , Vladimir N. Temlyakov

Motivated by online decision-making in time-varying combinatorial environments, we study the problem of transforming offline algorithms to their online counterparts. We focus on offline combinatorial problems that are amenable to a constant…

Machine Learning · Computer Science 2023-02-07 Rad Niazadeh , Negin Golrezaei , Joshua Wang , Fransisca Susan , Ashwinkumar Badanidiyuru

A $k$-submodular function naturally generalizes submodular functions by taking as input $k$ disjoint subsets, rather than a single subset. Unlike standard submodular maximization, which only requires selecting elements for the solution,…

Data Structures and Algorithms · Computer Science 2025-07-18 Chenhao Wang

A classic problem is the estimation of a set of parameters from measurements collected by only a few sensors. The number of sensors is often limited by physical or economical constraints and their placement is of fundamental importance to…

Information Theory · Computer Science 2015-06-16 Juri Ranieri , Amina Chebira , Martin Vetterli

We propose a variable decomposition algorithm -greedy block coordinate descent (GBCD)- in order to make dense Gaussian process regression practical for large scale problems. GBCD breaks a large scale optimization into a series of small…

Machine Learning · Computer Science 2012-06-18 Liefeng Bo , Cristian Sminchisescu

We demonstrate a simple greedy algorithm that can reliably recover a d-dimensional vector v from incomplete and inaccurate measurements x. Here our measurement matrix is an N by d matrix with N much smaller than d. Our algorithm,…

Numerical Analysis · Mathematics 2007-12-11 Deanna Needell , Roman Vershynin