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In this work, we consider the solution of fluid-structure interaction problems using a monolithic approach for the coupling between fluid and solid subproblems. The coupling of both equations is realized by means of the arbitrary…

Numerical Analysis · Mathematics 2018-03-09 D. Jodlbauer , U. Langer , T. Wick

We investigate efficient algorithmic realisations for robust deconvolution of grey-value images with known space-invariant point-spread function, with emphasis on 1D motion blur scenarios. The goal is to make deconvolution suitable as…

Computer Vision and Pattern Recognition · Computer Science 2017-09-22 Martin Welk , Patrik Raudaschl , Thomas Schwarzbauer , Martin Erler , Martin Läuter

In various verification systems, Restricted Boltzmann Machines (RBMs) have demonstrated their efficacy in both front-end and back-end processes. In this work, we propose the use of RBMs to the image clustering tasks. RBMs are trained to…

Computer Vision and Pattern Recognition · Computer Science 2024-01-17 Abraham Woubie , Enoch Solomon , Eyael Solomon Emiru

We present a sparse matrix permutation from graph theory that gives stable incomplete Lower-Upper (LU) preconditioners necessary for iterative solutions to the steady state density matrix for quantum optomechanical systems. This reordering…

Quantum Physics · Physics 2015-01-28 P. D. Nation , J. R. Johansson , M. P. Blencowe , A. J. Rimberg

Deep learning has been widely used for solving image reconstruction tasks but its deployability has been held back due to the shortage of high-quality training data. Unsupervised learning methods, such as the deep image prior (DIP),…

Computer Vision and Pattern Recognition · Computer Science 2023-06-06 Riccardo Barbano , Javier Antorán , Johannes Leuschner , José Miguel Hernández-Lobato , Bangti Jin , Željko Kereta

Blind motion deblurring is one of the most basic and challenging problems in image processing and computer vision. It aims to recover a sharp image from its blurred version knowing nothing about the blur process. Many existing methods use…

Computer Vision and Pattern Recognition · Computer Science 2019-01-09 Quan Yuan , Junxia Li , Lingwei Zhang , Zhefu Wu , Guangyu Liu

We describe and examine an algorithm for tomographic image reconstruction where prior knowledge about the solution is available in the form of training images. We first construct a nonnegative dictionary based on prototype elements from the…

Computer Vision and Pattern Recognition · Computer Science 2015-08-18 Sara Soltani , Martin S. Andersen , Per Christian Hansen

In this paper we study fast iterative solvers for the large sparse linear systems resulting from the stochastic Galerkin discretization of stochastic partial differential equations. A block triangular preconditioner is introduced and…

Numerical Analysis · Mathematics 2013-04-08 Bin Zheng , Guang Lin , Jinchao Xu

Traditional model-based image reconstruction (MBIR) methods combine forward and noise models with simple object priors. Recent application of deep learning methods for image reconstruction provides a successful data-driven approach to…

Image and Video Processing · Electrical Eng. & Systems 2022-05-20 Ling Chen , Zhishen Huang , Yong Long , Saiprasad Ravishankar

The restoration of images affected by blur and noise has been widely studied and has broad potential for applications including in medical imaging modalities like computed tomography (CT). Although the blur and noise in CT images can be…

Medical Physics · Physics 2024-07-23 Yijie Yuan , Grace J. Gang , J. Webster Stayman

There are two main streams in up-to-date image denoising algorithms: non-local self similarity (NSS) prior based methods and convolutional neural network (CNN) based methods. The NSS based methods are favorable on images with regular and…

Computer Vision and Pattern Recognition · Computer Science 2017-04-04 Byeongyong Ahn , Nam Ik Cho

In this paper, we propose a novel design of image deblurring in the form of one-shot convolution filtering that can directly convolve with naturally blurred images for restoration. The problem of optical blurring is a common disadvantage to…

Image and Video Processing · Electrical Eng. & Systems 2019-07-22 Mahdi S. Hosseini , Konstantinos N. Plataniotis

In this paper, we focus on solving a sequence of linear systems with an identical (or similar) coefficient matrix. For this type of problems, we investigate the subspace correction and deflation methods, which use an auxiliary matrix…

Numerical Analysis · Mathematics 2022-03-17 Takeshi Iwashita , Kota Ikehara , Takeshi Fukaya , Takeshi Mifune

Deepfake detection methods based on convolutional neural networks (CNN) have demonstrated high accuracy. \textcolor{black}{However, these methods often suffer from decreased performance when faced with unknown forgery methods and common…

Computer Vision and Pattern Recognition · Computer Science 2023-07-14 Sitong Liu , Zhichao Lian , Siqi Gu , Liang Xiao

A family of the Block Matching 3-D (BM3D) algorithms for various imaging problems has been recently proposed within the framework of nonlocal patch-wise image modeling [1], [2]. In this paper we construct analysis and synthesis frames,…

Optimization and Control · Mathematics 2015-05-28 Aram Danielyan , Vladimir Katkovnik , Karen Egiazarian

Variational regularization of ill-posed inverse problems is based on minimizing the sum of a data fidelity term and a regularization term. The balance between them is tuned using a positive regularization parameter, whose automatic choice…

Numerical Analysis · Mathematics 2025-11-12 Markus Juvonen , Bjørn Jensen , Ilmari Pohjola , Yiqiu Dong , Samuli Siltanen

We turn a given filter bank into a filtering scheme that provides perfect reconstruction, synthesis is the adjoint of the analysis part (so-called unitary filter banks), all filters have equal norm, and the essential features of the…

Functional Analysis · Mathematics 2017-09-04 Martin Ehler

The Block Transform Coded, JPEG- a lossy image compression format has been used to keep storage and bandwidth requirements of digital image at practical levels. However, JPEG compression schemes may exhibit unwanted image artifacts to…

Graphics · Computer Science 2012-08-10 Sukhpal Singh

We present an enhanced version of the row-based randomized block-Kaczmarz method to solve a linear system of equations. This improvement makes use of a regularization during block updates in the solution, and a dynamic proposal distribution…

Numerical Analysis · Mathematics 2025-10-03 Suvendu Kar , Murugesan Venkatapathi

Blind deconvolution is a technique to recover an original signal without knowing a convolving filter. It is naturally formulated as a minimization of a quartic objective function under some assumption. Because its differentiable part does…

Optimization and Control · Mathematics 2022-09-13 Shota Takahashi , Mirai Tanaka , Shiro Ikeda