Results 31 to 40 of about 179,319 (288)

Accelerated Projected Gradient Method for Linear Inverse Problems with Sparsity Constraints

, 2008
Regularization of ill-posed linear inverse problems via $\ell_1$ penalization has been proposed for cases where the solution is known to be (almost) sparse. One way to obtain the minimizer of such an $\ell_1$ penalized functional is via an iterative soft-
A. Chambolle, A. Cohen, A. Cohen, A. Cohen, A. Cohen, B. Efron, C. Canuto, D.L. Donoho, D.L. Donoho, D.L. Donoho, D.L. Donoho, D.L. Donoho, D.L. Donoho, E. Candès, E.J. Candès, E.J. Candès, E.J. Candès, G. Teschke, H. Rauhut, H.W. Engl, I. Daubechies, I. Daubechies, I. Daubechies, I. Loris, Ignace Loris, Ingrid Daubechies, J.-L. Starck, J.-L. Starck, L.M. Brègman, M. Fornasier, M. Fornasier, M. Fornasier, M. Fornasier, M.A.T. Figueiredo, M.A.T. Figueiredo, Massimo Fornasier, O. Christensen, P.L. Combettes, R. Ramlau, S. Dahlke, S. Dahlke, S. Dahlke, S. Mallat, S. Wolfram, Y.I. Alber   +44 more
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Analytical Low-Dose CBCT Reconstruction Using Non-local Total Variation Regularization for Image Guided Radiation Therapy

Frontiers in Oncology, 2020
Purpose: Conventional iterative low-dose CBCT reconstruction techniques are slow and tend to over-smooth edges through uniform weighting of the image penalty gradient.
James J. Sohn, Changsoo Kim, Dong Hyun Kim, Seu-Ran Lee, Jun Zhou, Xiaofeng Yang, Tian Liu   +6 more
doaj   +1 more source

Distributed Random Projection Algorithm for Convex Optimization

, 2013
Random projection algorithm is an iterative gradient method with random projections. Such an algorithm is of interest for constrained optimization when the constraint set is not known in advance or the projection operation on the whole constraint set is ...
Lee, Soomin, Nedich, Angelia
core   +1 more source

Existence of Solutions and Algorithm for a System of Variational Inequalities

Fixed Point Theory and Applications, 2010
We obtain some existence results for a system of variational inequalities (for short, denoted by SVI) by Brouwer fixed point theorem. We also establish the existence and uniqueness theorem using the projection technique for the SVI and suggest an ...
Yali Zhao, Zunquan Xia, Liping Pang, Liwei Zhang   +3 more
doaj   +2 more sources

A Conceptual Conjugate Epi-Projection Algorithm of Convex Optimization: Superlinear, Quadratic and Finite Convergence

, 2018
This paper considers a conceptual version of a convex optimization algorithm whic is based on replacing a convex optimization problem with the root-finding problem for the approximate sub-differential mapping which is solved by repeated projection onto ...
Nurminski, Evgeni
core   +1 more source

Fused Analytical and Iterative Reconstruction (AIR) via modified proximal forward-backward splitting: a FDK-based iterative image reconstruction example for CBCT

, 2016
This work is to develop a general framework, namely analytical iterative reconstruction (AIR) method, to incorporate analytical reconstruction (AR) method into iterative reconstruction (IR) method, for enhanced CT image quality and reconstruction ...
Gao, Hao
core   +1 more source

Improved inertial projection and contraction method for solving pseudomonotone variational inequality problems

Journal of Inequalities and Applications, 2021
The objective of this article is to solve pseudomonotone variational inequality problems in a real Hilbert space. We introduce an inertial algorithm with a new self-adaptive step size rule, which is based on the projection and contraction method.
Ming Tian, Gang Xu
doaj   +1 more source

Live Iterative Ptychography with Projection-Based Algorithms

ICASSP 2024 - 2024 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP)
In this work, we demonstrate that the ptychographic phase problem can be solved in a live fashion during scanning, while data is still being collected. We propose a generally applicable modification of the widespread projection-based algorithms such as Error Reduction (ER) and Difference Map (DM).
Welker, Simon, Peer, Tal, Chapman, Henry N., Gerkmann, Timo   +3 more
openaire   +4 more sources

An iterative projections algorithm for ML factor analysis [PDF]

2008 IEEE Workshop on Machine Learning for Signal Processing, 2008
Alternating minimization of the information divergence is used to derive an effective algorithm for maximum likelihood (ML) factor analysis. The proposed algorithm is derived as an iterative alternating projections procedure on a model family of probability distributions defined on the factor analysis model and a desired family of probability ...
openaire   +1 more source

A Lyapunov-type approach to convergence of the Douglas-Rachford algorithm

, 2017
The Douglas-Rachford projection algorithm is an iterative method used to find a point in the intersection of closed constraint sets. The algorithm has been experimentally observed to solve various nonconvex feasibility problems which current theory ...
Dao, Minh N., Tam, Matthew K.
core   +1 more source