English
Related papers

Related papers: Local precised approximation in multiscale problem…

200 papers

This note is devoted to some nonlocal, nonlinear elliptic problems with an emphasis on the computation of the solution of such problems, reducing it in particular to a fixed point argument in R. Errors estimates and numerical experiments…

Analysis of PDEs · Mathematics 2026-01-28 M. M. Chipot , A. Luthra , S. A. Sauter

This paper considers a time-fractional diffusion-wave equation with a high-contrast heterogeneous diffusion coefficient. A numerical solution to this problem can present great computational challenges due to its multiscale nature.…

Numerical Analysis · Mathematics 2025-02-14 Huiran Bai , Dmitry Ammosov , Yin Yang , Wei Xie , Mohammed Al Kobaisi

We show that the gradient of the $m$-power of a solution to a singular parabolic equation of porous medium-type (also known as fast diffusion equation), satisfies a reverse H\"older inequality in suitable intrinsic cylinders. Relying on an…

Analysis of PDEs · Mathematics 2019-08-21 Ugo Gianazza , Sebastian Schwarzacher

The spectral problem for an infinite periodic medium perturbed by a compact defect is considered. For a high contrast small $\ve$-size periodicity and a finite size defect we consider the critical $\ve^2$-scaling for the contrast. We employ…

Spectral Theory · Mathematics 2018-01-11 I. V. Kamotski , V. P. Smyshlyaev

The $hp$ local discontinuous Galerkin (LDG) method proposed by Castillo et al. [Math. Comp.,~71 (238): 455-478, 2002] has been shown to be an efficient approach for solving convection-diffusion equations. However, theoretical analysis…

Numerical Analysis · Mathematics 2026-03-05 Wenjie Liu , Ruiyi Xie , Li-Lian Wang , Zhimin Zhang

Reference-guided image generation has progressed rapidly, yet current diffusion models still struggle to preserve fine-grained visual details when refining a generated image using a reference. This limitation arises because VAE-based latent…

Computer Vision and Pattern Recognition · Computer Science 2025-11-26 Yaoli Liu , Ziheng Ouyang , Shengtao Lou , Yiren Song

This paper addresses the complexity reduction of stochastic homogenisation of a class of random materials for a stationary diffusion equation. A cost-efficient approximation of the correctors is built using a method designed to exploit…

Numerical Analysis · Mathematics 2022-03-25 Quentin Ayoul-Guilmard , Anthony Nouy , Christophe Binetruy

We prove local higher integrability of the spatial gradient for solutions to obstacle problems of porous medium type in the fast diffusion case $m<1$. The result holds for the natural range of exponents that is known from other regularity…

Analysis of PDEs · Mathematics 2020-04-16 Yumi Cho , Christoph Scheven

We consider the numerical approximation of the radiative transfer equation using discontinuous angular and continuous spatial approximations for the even parts of the solution. The even-parity equations are solved using a diffusion…

Numerical Analysis · Mathematics 2019-09-19 Olena Palii , Matthias Schlottbom

In this work, a complete error analysis is presented for fully discrete solutions of the subdiffusion equation with a time-dependent diffusion coefficient, obtained by the Galerkin finite element method with conforming piecewise linear…

Numerical Analysis · Mathematics 2018-09-24 Bangti Jin , Buyang Li , Zhi Zhou

We establish an optimal, linear rate of convergence for the stochastic homogenization of discrete linear elliptic equations. We consider the model problem of independent and identically distributed coefficients on a discretized unit torus.…

Numerical Analysis · Mathematics 2019-02-20 Antoine Gloria , Stefan Neukamm , Felix Otto

We describe acceleration of the front propagation for solutions to a class of monostable nonlinear equations with a nonlocal diffusion in $\mathbb{R}^d$, $d\geq1$. We show that the acceleration takes place if either the diffusion kernel or…

Analysis of PDEs · Mathematics 2018-06-07 Dmitri Finkelshtein , Yuri Kondratiev , Pasha Tkachov

We analyze upwind difference methods for strongly degenerate convection-diffusion equations in several spatial dimensions. We prove that the local $L^1$-error between the exact and numerical solutions is $\mathcal{O}(\Delta x^{2/(19+d)})$,…

Analysis of PDEs · Mathematics 2015-09-07 Kenneth Hvistendahl Karlsen , Nils Henrik Risebro , Erlend Briseid Storrøsten

In this paper, we consider several possible ways to set up Heterogeneous Multiscale Methods for the Landau-Lifshitz equation with a highly oscillatory diffusion coefficient, which can be seen as a means to modeling rapidly varying…

Numerical Analysis · Mathematics 2021-04-08 Lena Leitenmaier , Olof Runborg

In this short note we have proved an enhanced version of a theorem of Lorentz [1] and its generalization to the multivariate case which gives a non- uniform estimate of degree of approximation by a polynomial with positive coefficients. The…

Classical Analysis and ODEs · Mathematics 2016-11-30 Zhong Guan , Tao Wang

This paper is devoted to the homogenization of Shr\"odinger type equations with periodically oscillating coefficients of the diffusion term, and a rapidly oscillating periodic time-dependent potential. One convergence theorem is proved and…

Analysis of PDEs · Mathematics 2016-11-29 Lazarus Signing

We study the quantitative homogenization of linear second order elliptic equations in non-divergence form with highly oscillating periodic diffusion coefficients and with large drifts, in the so-called ``centered'' setting where…

Analysis of PDEs · Mathematics 2023-07-10 Wenjia Jing , Yiping Zhang

Consider a discrete uniformly elliptic divergence form equation on the $d$ dimensional lattice $\Z^d$ with random coefficients. In [3] rate of convergence results in homogenization and estimates on the difference between the averaged…

Analysis of PDEs · Mathematics 2014-02-26 Joseph G. Conlon , Arash Fahim

This paper concentrates on the quantitative homogenization of higher-order elliptic systems with almost-periodic coefficients in bounded Lipschitz domains. For coefficients which are almost-periodic in the sense of H. Weyl, we establish…

Analysis of PDEs · Mathematics 2020-01-30 Yao Xu , Weisheng Niu

This paper is devoted to numerical approximations for the wave equation with a multiscale character. Our approach is formulated in the framework of the Localized Orthogonal Decomposition (LOD) interpreted as a numerical homogenization with…

Numerical Analysis · Mathematics 2015-09-23 Assyr Abdulle , Patrick Henning