English
Related papers

Related papers: Recovering Fine Details from Under-Resolved Electr…

200 papers

In this paper, we consider an inverse space-dependent source problem for a time-fractional diffusion equation. To deal with the ill-posedness of the problem, we transform the problem into an optimal control problem with total variational…

Optimization and Control · Mathematics 2025-01-15 Bin Fan

We consider a bilevel optimisation approach for parameter learning in higher-order total variation image reconstruction models. Apart from the least squares cost functional, naturally used in bilevel learning, we propose and analyse an…

Optimization and Control · Mathematics 2020-02-13 J. C. De los Reyes , C. -B. Schönlieb , T. Valkonen

In this article, we study several reconstruction methods for the inverse source problem of photoacoustic tomography (PAT) with spatially variable sound speed and damping. The backbone of these methods is the adjoint operators, which we…

Analysis of PDEs · Mathematics 2018-08-21 Linh V. Nguyen , Markus Haltmeier

Total-variation (TV)-based Computed Tomography (CT) image reconstruction has shown experimentally to be capable of producing accurate reconstructions from sparse-view data. In particular TV-based reconstruction is very well suited for…

In this paper we consider the reconstruction problem of photoacoustic tomography (PAT) with a flat observation surface. We develop a direct reconstruction method that employs regularization with wavelet sparsity constraints. To that end, we…

Optimization and Control · Mathematics 2017-03-27 Jürgen Frikel , Markus Haltmeier

Purpose: We develop an iterative image-reconstruction algorithm for application to low-intensity computed tomography (CT) projection data, which is based on constrained, total-variation (TV) minimization. The algorithm design focuses on…

Medical Physics · Physics 2015-05-20 Emil Y. Sidky , Yuval Duchin , Christer Ullberg , Xiaochuan Pan

We present a practical implementation of an optimal first-order method, due to Nesterov, for large-scale total variation regularization in tomographic reconstruction, image deblurring, etc. The algorithm applies to $\mu$-strongly convex…

In the present paper we propose two new algorithms of tensor completion for three-order tensors. The proposed methods consist in minimizing the average rank of the underlying tensor using its approximate function namely the tensor nuclear…

Numerical Analysis · Mathematics 2021-02-23 A. H. Bentbib , A. El Hachimi , K. Jbilou , A. Ratnani

Linear approximation approaches suffer from Gibbs oscillations when approximating functions with singularities. ENO-SR resolution is a local approach avoiding oscillations and with a full order of accuracy, but a loss of regularity of the…

Numerical Analysis · Mathematics 2021-04-13 Sergio Amat , David Levin , Juan Ruiz-Álvarez

The cross-channel deblurring problem in color image processing is difficult to solve due to the complex coupling and structural blurring of color pixels. Until now, there are few efficient algorithms that can reduce color artifacts in…

Computer Vision and Pattern Recognition · Computer Science 2025-01-28 Zhigang Jia , Yuelian Xiang , Meixiang Zhao , Tingting Wu , Michael K. Ng

Convex regularizers are often used for sparse learning. They are easy to optimize, but can lead to inferior prediction performance. The difference of $\ell_1$ and $\ell_2$ ($\ell_{1-2}$) regularizer has been recently proposed as a nonconvex…

Machine Learning · Computer Science 2017-06-21 Quanming Yao , James T. Kwok , Xiawei Guo

The aim of this paper is to establish a nonlinear variational approach to the reconstruction of moving density images from indirect dynamic measurements. Our approach is to model the dynamics as a hyperelastic deformation of an initial…

Numerical Analysis · Mathematics 2015-12-01 Martin Burger , Jan Modersitzki , Sebastian Suhr

Super-resolution is generally referred to as the task of recovering fine details from coarse information. Motivated by applications such as single-molecule imaging, radar imaging, etc., we consider parameter estimation of complex…

Information Theory · Computer Science 2016-08-10 Dehui Yang , Gongguo Tang , Michael B. Wakin

Sampling high-dimensional images is challenging due to limited availability of sensors; scanning is usually necessary in these cases. To mitigate this challenge, snapshot compressive imaging (SCI) was proposed to capture the…

Image and Video Processing · Electrical Eng. & Systems 2020-05-19 Xin Yuan

Fluorescence molecular tomography (FMT) is an emerging powerful tool for biomedical research. There are two factors that influence FMT reconstruction most effectively. The first one is the regularization techniques. Traditional methods such…

Image and Video Processing · Electrical Eng. & Systems 2021-09-09 Yan Liu , Wuwei Ren , Habib Ammari

An optimization framework is presented for minimizing the energy functional developed around a generalized equation governing physical systems such as fluid dynamics, particle transport, phase transition, and other related systems. The…

Fluid Dynamics · Physics 2024-04-25 Varsha Gupta

Low-dose computed tomography (LDCT) reduces patient radiation exposure but introduces substantial noise that degrades image quality and hinders diagnostic accuracy. Existing denoising approaches often require many diffusion steps, limiting…

Medical Physics · Physics 2025-10-29 Qiang Li , Mojtaba Safari , Shansong Wang , Huiqiao Xie , Jie Ding , Tonghe Wang , Xiaofeng Yang

Extreme learning machine (ELM) is a network model that arbitrarily initializes the first hidden layer and can be computed speedily. In order to improve the classification performance of ELM, a $\ell_2$ and $\ell_{0.5}$ regularization ELM…

Optimization and Control · Mathematics 2023-01-05 Liangjuan Zhou , Wei Miao

In this work, we develop a novel technique for reconstructing images from projection-based nano- and microtomography. Our contribution focuses on enhancing reconstruction quality, particularly for specimen composed of homogeneous material…

Computer Vision and Pattern Recognition · Computer Science 2025-09-09 Anuraag Mishra , Andrea Gilch , Benjamin Apeleo Zubiri , Jan Rolfes , Frauke Liers

In this paper, we consider the inverse source problem for the time-fractional diffusion equation, which has been known to be an ill-posed problem. To deal with the ill-posedness of the problem, we propose to transform the problem into a…

Numerical Analysis · Mathematics 2021-08-27 Bin Fan , Chuanju Xu
‹ Prev 1 8 9 10 Next ›