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Related papers: Symmetrization in nonlocal diffusion problems

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The aim of this work is to study comparability of nonlocal Dirichlet forms. We provide sufficient conditions on the kernel for local and global comparability. As an application we prove a-priori estimates in H\"{o}lder spaces for solutions…

Analysis of PDEs · Mathematics 2011-10-03 Bartłomiej Dyda , Moritz Kassmann

In this paper, we study some qualitative properties for an evolution problem that combines local and nonlocal diffusion operators acting in two different subdomains and, coupled in such a way that, the resulting evolution problem is the…

Analysis of PDEs · Mathematics 2020-03-05 Bruna C. dos Santos , Sergio M. Oliva , Julio D. Rossi

This paper discusses the local linear smoothing to estimate the unknown first and second infinitesimal moments in second-order jump-diffusion model based on Gamma asymmetric kernels. Under the mild conditions, we obtain the weak consistency…

Statistics Theory · Mathematics 2017-07-07 Yuping Song , Hanchao Wang

In this note we prove a new symmetrization result, in the form of mass concentration comparison, for solutions of nonlocal nonlinear Dirichlet problems involving fractional p Laplacians. Some regularity estimates of solutions will be…

Analysis of PDEs · Mathematics 2022-05-13 Vincenzo Ferone , Bruno Volzone

We present an approach to handle Dirichlet type nonlocal boundary conditions for nonlocal diffusion models with a finite range of nonlocal interactions. Our approach utilizes a linear extrapolation of prescribed boundary data. A novelty is,…

Analysis of PDEs · Mathematics 2021-08-27 Hwi Lee , Qiang Du

Similarity reductions and new exact solutions are obtained for a nonlinear diffusion equation. These are obtained by using the classical symmetry group and reducing the partial differential equation to various ordinary differential…

Analysis of PDEs · Mathematics 2015-06-26 Maria Luz Gandarias , P. Venero , José Ramírez-Labrador

The global existence of renormalised solutions and convergence to equilibrium for reaction-diffusion systems with non-linear diffusion are investigated. The system is assumed to have quasi-positive non-linearities and to satisfy an entropy…

Analysis of PDEs · Mathematics 2021-09-27 Klemens Fellner , Julian Fischer , Michael Kniely , Bao Quoc Tang

This work addresses the regularity of solutions for a nonlocal diffusion equation over the space of periodic distributions. The spatial operator for the nonlocal diffusion equation is given by a nonlocal Laplace operator with a compactly…

Analysis of PDEs · Mathematics 2022-10-04 Ilyas Mustapha , Bacim Alali , Nathan Albin

This work considers a nonlinear inverse source problem in a coupled diffusion equation from the terminal observation. Theoretically, under some conditions on problem data, we build the uniqueness theorem for this inverse problem and show…

Numerical Analysis · Mathematics 2025-04-29 Chunlong Sun , Wenlong Zhang , Zhidong Zhang

Diffusion models have recently emerged as powerful generative priors for solving inverse problems. However, training diffusion models in the pixel space are both data-intensive and computationally demanding, which restricts their…

Computer Vision and Pattern Recognition · Computer Science 2024-04-17 Bowen Song , Soo Min Kwon , Zecheng Zhang , Xinyu Hu , Qing Qu , Liyue Shen

We establish a new symmetrization procedure for the isoperimetric problem in symmetric spaces of noncompact type. This symmetrization generalizes the well known Steiner symmetrization in euclidean space. In contrast to the classical…

Differential Geometry · Mathematics 2007-05-23 Daniel John

We prove Holder regularity for solutions of non divergence integro-differential equations with non necessarily even kernels. The even/odd decomposition of the kernel can be understood as a sum of a diffusion and a drift term. In our case we…

Analysis of PDEs · Mathematics 2012-10-31 Hector A. Chang Lara

We prove pointwise and $L^{p}$-gradient comparison results for solutions to elliptic Dirichlet problems defined on open subsets of a (possibly non-smooth) space with positive Ricci curvature (more precisely of an $\mathrm{RCD}(K,N)$ metric…

Analysis of PDEs · Mathematics 2022-11-11 Andrea Mondino , Mattia Vedovato

We introduce a framework for designing efficient diffusion models for $d$-dimensional symmetric-space Riemannian manifolds, including the torus, sphere, special orthogonal group and unitary group. Existing manifold diffusion models often…

Machine Learning · Computer Science 2025-05-29 Oren Mangoubi , Neil He , Nisheeth K. Vishnoi

We consider the classical Holling-Tanner model extended on 1D space by introducing the diffusion term. Making a reasonable simplification, the diffusive Holling-Tanner system is studied by means of symmetry based methods. Lie and…

Mathematical Physics · Physics 2024-03-01 Roman Cherniha , Vasyl' Davydovych

The problem of identifying the diffusion parameter appearing in a nonlocal steady diffusion equation is considered. The identification problem is formulated as an optimal control problem having a matching functional as the objective of the…

Optimization and Control · Mathematics 2015-02-03 Marta D'Elia , Max Gunzburger

From a systems biology perspective the majority of cancer models, although interesting and providing a qualitative explanation of some problems, have a major disadvantage in that they usually miss a genuine connection with experimental…

Statistics Theory · Mathematics 2023-05-25 Zuzanna Szymańska , Jakub Skrzeczkowski , Błażej Miasojedow , Piotr Gwiazda

In this short article, we shall study one-dimensional local Dirichlet spaces. One result, which has its independent interest, is to prove that irreducibility implies the uniqueness of symmetrizing measure for right Markov processes. The…

Probability · Mathematics 2009-08-13 Xing Fang , Jiangang Ying , Minzhi Zhao

We propose finite difference methods for degenerate fully nonlinear elliptic equations and prove the convergence of the schemes. Our focus is on the pure equation and a related free boundary problem of transmission type. The cornerstone of…

Numerical Analysis · Mathematics 2025-06-04 Edgard A. Pimentel , Ercília Sousa

Generative diffusion models can provide powerful prior probability models for inverse problems in imaging, but existing implementations suffer from two key limitations: $(i)$ the prior density is represented implicitly, and $(ii)$ they rely…

Machine Learning · Computer Science 2026-05-19 Nicolas Zilberstein , Santiago Segarra , Eero Simoncelli , Florentin Guth