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Related papers: Error analysis of some nonlocal diffusion discreti…

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Often computational models are too expensive to be solved in the entire domain of simulation, and a cheaper model would suffice away from the main zone of interest. We present for the concrete example of an evolution problem of advection…

Numerical Analysis · Mathematics 2014-09-15 Martin J. Gander , Laurence Halpern , Véronique Martin

Diffusion and flow-based generative models have shown strong potential for image restoration. However, image denoising under unknown and varying noise conditions remains challenging, because the learned vector fields may become inconsistent…

Computer Vision and Pattern Recognition · Computer Science 2026-04-06 Jigang Duan , Genwei Ma , Xu Jiang , Wenfeng Xu , Ping Yang , Xing Zhao

In this paper, we consider effective discretization strategies and iterative solvers for nonlinear PDE-constrained optimization models for pattern evolution within biological processes. Upon a Sequential Quadratic Programming linearization…

Numerical Analysis · Mathematics 2024-08-28 Karolína Benková , John W. Pearson , Mariya Ptashnyk

We consider the problem of discrete-time signal denoising, focusing on a specific family of non-linear convolution-type estimators. Each such estimator is associated with a time-invariant filter which is obtained adaptively, by solving a…

Statistics Theory · Mathematics 2018-06-13 Dmitrii Ostrovskii , Zaid Harchaoui

In this paper we consider the fundamental operations dilation and erosion of mathematical morphology. Many powerful image filtering operations are based on their combinations. We establish homomorphism between max-plus semi-ring of integers…

Image and Video Processing · Electrical Eng. & Systems 2023-05-05 Vivek Sridhar , Keyvan Shahin , Michael Breuß , Marc Reichenbach

This paper demonstrates a practical method that can correct spatial varying blur from a set of images of the same object. The algorithm jointly estimates the object and local point spread functions~(PSF). The method prioritizes sections…

Image and Video Processing · Electrical Eng. & Systems 2020-11-04 Wouter van de Ketterij , Oleg Soloviev , Michel Verhaegen

Diffusion models have had a profound impact on many application areas, including those where data are intrinsically infinite-dimensional, such as images or time series. The standard approach is first to discretize and then to apply…

Machine Learning · Statistics 2025-06-09 Jakiw Pidstrigach , Youssef Marzouk , Sebastian Reich , Sven Wang

We develop a novel iterative algorithm for locally optimal experimental design under constraints, like budget or performance constraints. It is an adaptive discretization algorithm. In every iteration, a discretized version of the…

Optimization and Control · Mathematics 2026-04-21 Jochen Schmid , Philipp Seufert , Jan Schwientek , Tobias Seidel , Karl-Heinz Küfer

Denoising diffusions are state-of-the-art generative models exhibiting remarkable empirical performance. They work by diffusing the data distribution into a Gaussian distribution and then learning to reverse this noising process to obtain…

Machine Learning · Statistics 2024-02-20 Joe Benton , Yuyang Shi , Valentin De Bortoli , George Deligiannidis , Arnaud Doucet

We study the problem of computing the value function from a discretely-observed trajectory of a continuous-time diffusion process. We develop a new class of algorithms based on easily implementable numerical schemes that are compatible with…

Machine Learning · Computer Science 2024-07-09 Wenlong Mou , Yuhua Zhu

This paper is devoted to the error analysis of a time-spectral algorithm for fractional diffusion problems of order $\alpha$ ($0 < \alpha < 1$). The solution regularity in the Sobolev space is revisited, and new regularity results in the…

Numerical Analysis · Mathematics 2021-06-08 Hao Luo , Xiaoping Xie

The recent emergence of diffusion models has significantly advanced the precision of learnable priors, presenting innovative avenues for addressing inverse problems. Since inverse problems inherently entail maximum a posteriori estimation,…

Machine Learning · Computer Science 2025-01-22 Jiawei Zhang , Jiaxin Zhuang , Cheng Jin , Gen Li , Yuantao Gu

In this paper we design efficient quadrature rules for finite element discretizations of nonlocal diffusion problems with compactly supported kernel functions. Two of the main challenges in nonlocal modeling and simulations are the…

Numerical Analysis · Mathematics 2021-09-23 Eugenio Aulisa , Giacomo Capodaglio , Andrea Chierici , Marta D'Elia

An approximation to the solution of a stochastic parabolic equation is constructed using the Galerkin approximation followed by the Wiener Chaos decomposition. The result is applied to the nonlinear filtering problem for the time…

Probability · Mathematics 2007-06-13 Sergey V. Lototsky

In this article, we discuss the numerical solution of diffusion equations on random surfaces within the isogeometric framework. We describe in detail, how diffusion problems on random surfaces can be modelled and how quantities of interest…

Numerical Analysis · Mathematics 2022-04-28 Wei Huang , Michael Multerer

Denoising diffusion models are a novel class of generative algorithms that achieve state-of-the-art performance across a range of domains, including image generation and text-to-image tasks. Building on this success, diffusion models have…

Machine Learning · Computer Science 2024-03-08 Nic Fishman , Leo Klarner , Valentin De Bortoli , Emile Mathieu , Michael Hutchinson

Driven by the need to solve increasingly complex optimization problems in signal processing and machine learning, there has been increasing interest in understanding the behavior of gradient-descent algorithms in non-convex environments.…

Optimization and Control · Mathematics 2019-07-04 Stefan Vlaski , Ali H. Sayed

Diffusion models (DMs) are generative models that learn to synthesize images from Gaussian noise. DMs can be trained to do a variety of tasks such as image generation and image super-resolution. Researchers have made significant…

Computer Vision and Pattern Recognition · Computer Science 2025-03-04 Yung Jer Wong , Teck Khim Ng

Diffusion models have recently achieved great success in the synthesis of high-quality images and videos. However, the existing denoising techniques in diffusion models are commonly based on step-by-step noise predictions, which suffers…

Computer Vision and Pattern Recognition · Computer Science 2024-10-15 Hancheng Ye , Jiakang Yuan , Renqiu Xia , Xiangchao Yan , Tao Chen , Junchi Yan , Botian Shi , Bo Zhang

We introduce an exact reformulation of a broad class of neighborhood filters, among which the bilateral filters, in terms of two functional rearrangements: the decreasing and the relative rearrangements. Independently of the image spatial…

Computer Vision and Pattern Recognition · Computer Science 2024-01-29 Gonzalo Galiano , Julián Velasco