158 citations · 311 across the 12 of their papers we have counts for
13 papers
Fast Data-Driven Learning of MRI Sampling Pattern for Large Scale Problems
Marcelo V. W. Zibetti, Gabor T. Herman, Ravinder R. Regatte
Purpose: A fast data-driven optimization approach, named bias-accelerated subset selection (BASS), is proposed for learning efficacious sampling patterns (SPs) with the purpose of…
Fast Proximal Gradient Methods for Nonsmooth Convex Optimization for Tomographic Image Reconstruction
Elias S. Helou, Marcelo V. W. Zibetti, Gabor T. Herman
The Fast Proximal Gradient Method (FPGM) and the Monotone FPGM (MFPGM) for minimization of nonsmooth convex functions are introduced and applied to tomographic image reconstruction…
Problem Structures in the Theory and Practice of Superiorization
Gabor T. Herman
The purpose of this short paper is to identify the mathematical essence of the superiorization methodology. This methodology has been developed in recent years while attempting to…
Derivative-Free Superiorization: Principle and Algorithm
Yair Censor, Edgar Garduño, Elias S. Helou +1
The superiorization methodology is intended to work with input data of constrained minimization problems, that is, a target function and a set of constraints. However, it is based…
The Discrete Fourier Transform for Golden Angle Linogram Sampling
Elias S. Helou, Marcelo V. W. Zibetti, Leon Axel +3
Estimation of the Discrete-Time Fourier Transform (DTFT) at points of a finite domain arises in many imaging applications. A new approach to this task, the Golden Angle Linogram Fo…
Superiorization of Preconditioned Conjugate Gradient Algorithms for Tomographic Image Reconstruction
Elias S. Helou, Gabor T. Herman, Chuan Lin +1
Properties of Superiorized Preconditioned Conjugate Gradient (SupPCG) algorithms in image reconstruction from projections are examined. Least squares (LS) is usually chosen for mea…
String-Averaging Algorithms for Convex Feasibility with Infinitely Many Sets
T. Yung Kong, Homeira Pajoohesh, Gabor T. Herman
Algorithms for convex feasibility find or approximate a point in the intersection of given closed convex sets. Typically there are only finitely many convex sets, but the case of i…
Total Variation Superiorized Conjugate Gradient Method for Image Reconstruction
Marcelo V. W. Zibetti, Chuan Lin, Gabor T. Herman
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…
Computerized Tomography with Total Variation and with Shearlets
Edgar Garduño, Gabor T. Herman
To reduce the x-ray dose in computerized tomography (CT), many constrained optimization approaches have been proposed aiming at minimizing a regularizing function that measures lac…
Projected Subgradient Minimization versus Superiorization
Yair Censor, Ran Davidi, Gabor T. Herman +2
The projected subgradient method for constrained minimization repeatedly interlaces subgradient steps for the objective function with projections onto the feasible region, which is…
Superiorization: An optimization heuristic for medical physics
G. T. Herman, E. Garduño, R. Davidi +1
Purpose: To describe and mathematically validate the superiorization methodology, which is a recently-developed heuristic approach to optimization, and to discuss its applicability…
Perturbation Resilience and Superiorization of Iterative Algorithms
Y. Censor, R. Davidi, G. T. Herman
Iterative algorithms aimed at solving some problems are discussed. For certain problems, such as finding a common point in the intersection of a finite number of convex sets, there…
On the Effectiveness of Projection Methods for Convex Feasibility Problems with Linear Inequality Constraints
Y. Censor, W. Chen, P. L. Combettes +2
The effectiveness of projection methods for solving systems of linear inequalities is investigated. It is shown that they have a computational advantage over some alternatives and…