English
Related papers

Related papers: An algorithm for constrained one-step inversion of…

200 papers

In this paper, a multi-parameterized proximal point algorithm combining with a relaxation step is developed for solving convex minimization problem subject to linear constraints. We show its global convergence and sublinear convergence rate…

Numerical Analysis · Mathematics 2019-07-11 Jianchao Bai , Ke Guo , Xiaokai Chang

We study iterative signal reconstruction in computed tomography (CT), wherein measurements are produced by a linear transformation of the unknown signal followed by an exponential nonlinear map. Approaches based on pre-processing the data…

Optimization and Control · Mathematics 2024-07-19 Vasileios Charisopoulos , Rebecca Willett

Transformers are very powerful tools for a variety of tasks across domains, from text generation to image captioning. However, transformers require substantial amounts of training data, which is often a challenge in biomedical settings,…

Computer Vision and Pattern Recognition · Computer Science 2023-07-04 Andrew Kean Gao

When an inverse problem is solved by a gradient-based optimization algorithm, the corresponding forward and adjoint problems, which are introduced to compute the gradient, can be also solved iteratively. The idea of iterating at the same…

Numerical Analysis · Mathematics 2025-01-23 Marcella Bonazzoli , Houssem Haddar , Tuan Anh Vu

We derive several numerical methods for designing optimized first-order algorithms in unconstrained convex optimization settings. Our methods are based on the Performance Estimation Problem (PEP) framework, which casts the worst-case…

Optimization and Control · Mathematics 2025-07-29 Yassine Kamri , Julien M. Hendrickx , François Glineur

Aims. To investigate the performance of a deconvolution map-making algorithm for an experiment with a circular scanning strategy, specifically in this case for the analysis of Planck data, and to quantify the effects of making maps using…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 D. L. Harrison , F. van Leeuwen , M. A. J. Ashdown

Retrieving a signal from its triple correlation spectrum, also called bispectrum, arises in a wide range of signal processing problems. Conventional methods do not provide an accurate inversion of bispectrum to the underlying signal. In…

Signal Processing · Electrical Eng. & Systems 2023-06-09 Samuel Pinilla , Kumar Vijay Mishra , Brian M. Sadler

Spectral compressive imaging (SCI) is able to encode the high-dimensional hyperspectral image to a 2D measurement, and then uses algorithms to reconstruct the spatio-spectral data-cube. At present, the main bottleneck of SCI is the…

Image and Video Processing · Electrical Eng. & Systems 2023-07-04 Lishun Wang , Zongliang Wu , Yong Zhong , Xin Yuan

Computed Tomography (CT) imaging is one of the most influential diagnostic methods. In clinical reconstruction, an effective energy is used instead of total X-ray spectrum. This approximation causes an accuracy decline. To increase the…

Emerging Technologies · Computer Science 2018-07-25 Neda Gholami , Mohammad Mahdi Dehshibi , Mahmood Fazlali , Antonio Rueda-Toicen , Hector Zenil , Andrew Adamatzky

In this paper, we consider optimizing a smooth, convex, lower semicontinuous function in Riemannian space with constraints. To solve the problem, we first convert it to a dual problem and then propose a general primal-dual algorithm to…

Machine Learning · Computer Science 2020-05-20 Shijun Wang , Baocheng Zhu , Lintao Ma , Yuan Qi

We consider the problem of finding the minimizations of the sum of two convex functions and the composition of another convex function with a continuous linear operator from the view of fixed point algorithms based on proximity operators,…

Optimization and Control · Mathematics 2016-04-18 Meng Wen , Yu-Chao Tang , Jigen Peng

Model-based material decomposition is a statisticaliterative reconstruction framework where basis material densityimages are estimated directly from spectral CT data. This methoduses a physical model for polyenergetic x-ray transmission…

Medical Physics · Physics 2020-10-06 Matthew Tivnan , Wenying Wang , J. Webster Stayman

The purpose of this work is to provide a fast and accurate scatter artifacts correction algorithm for cone beam CT (CBCT) imaging. The method starts with an estimation of coarse scatter profiles for a set of CBCT data in either image domain…

Medical Physics · Physics 2016-04-27 Wei Zhao , Don Vernekohl , Jun Zhu , Luyao Wang , Lei Xing

An important form of prior information in clustering comes in form of cannot-link and must-link constraints. We present a generalization of the popular spectral clustering technique which integrates such constraints. Motivated by the…

Machine Learning · Statistics 2015-05-26 Syama Sundar Rangapuram , Matthias Hein

In this work, we develop proximal preconditioned gradient methods with a focus on spectral gradient methods providing a proximal extension to the Muon and Scion optimizers. We introduce a family of stochastic algorithms that can handle a…

We present a rectangle-based segmentation algorithm that sets up a graph and performs a graph cut to separate an object from the background. However, graph-based algorithms distribute the graph's nodes uniformly and equidistantly on the…

Computer Vision and Pattern Recognition · Computer Science 2012-03-14 Jan Egger , Tina Kapur , Thomas Dukatz , Malgorzata Kolodziej , Dzenan Zukic , Bernd Freisleben , Christopher Nimsky

This paper develops a continuous-time primal-dual accelerated method with an increasing damping coefficient for a class of convex optimization problems with affine equality constraints. This paper analyzes critical values for parameters in…

Optimization and Control · Mathematics 2022-02-16 Xianlin Zeng , Jinlong Lei , Jie Chen

Block Coordinate Update (BCU) methods enjoy low per-update computational complexity because every time only one or a few block variables would need to be updated among possibly a large number of blocks. They are also easily parallelized and…

Optimization and Control · Mathematics 2017-11-22 Yangyang Xu , Shuzhong Zhang

Gradient descent algorithms perform well in convex optimization but can get tied for finding local minima in non-convex optimization. A robust method that combines a spectral approach with nonmonotone line search strategy for solving…

Optimization and Control · Mathematics 2025-01-07 Oday Hazaimah

In this paper we consider a distributed optimization scenario in which the aggregate objective function to minimize is partitioned, big-data and possibly non-convex. Specifically, we focus on a set-up in which the dimension of the decision…

Distributed, Parallel, and Cluster Computing · Computer Science 2017-03-27 Ivano Notarnicola , Giuseppe Notarstefano