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Related papers: Space-Fractional Diffusion with Variable Order and…

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The equation with the time fractional substantial derivative and space fractional derivative describes the distribution of the functionals of the L\'evy flights; and the equation is derived as the macroscopic limit of the continuous time…

Numerical Analysis · Mathematics 2015-04-27 Minghua Chen , Weihua Deng

High order discretization schemes play more important role in fractional operators than classical ones. This is because usually for classical derivatives the stencil for high order discretization schemes is wider than low order ones; but…

Numerical Analysis · Mathematics 2014-09-05 Minghua Chen , Weihua Deng

Solving the reactive low-Mach Navier-Stokes equations with high-order adaptive methods in time is still a challenging problem, in particular due to the handling of the algebraic variables involved in the mass constraint. We focus on the…

Analysis of PDEs · Mathematics 2025-10-02 Laurent François , Joël Dupays , Dmitry Davidenko , Marc Massot

This article devotes to developing robust but simple correction techniques and efficient algorithms for a class of second-order time stepping methods, namely the shifted fractional trapezoidal rule (SFTR), for subdiffusion problems to…

Numerical Analysis · Mathematics 2020-10-26 Baoli Yin , Yang Liu , Hong Li , Zhimin Zhang

In this paper we investigate an adaptive discretization strategy for ill-posed linear prob- lems combined with a regularization from a class of semiiterative methods. We show that such a discretization approach in combination with a…

Numerical Analysis · Mathematics 2014-07-22 Wolfgang Erb , Evgeniya V. Semenova

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

In this paper we propose optimisation methods for variational regularisation problems based on discretising the inverse scale space flow with discrete gradient methods. Inverse scale space flow generalises gradient flows by incorporating a…

Optimization and Control · Mathematics 2020-02-11 Martin Benning , Erlend S. Riis , Carola-Bibiane Schönlieb

We present recent finite element numerical results on a model convection-diffusion problem in the singular perturbed case when the convection term dominates the problem. We compare the standard Galerkin discretization using the linear…

Numerical Analysis · Mathematics 2023-02-16 Constantin Bacuta , Daniel Hayes , Tyler O'Grady

For the Poisson equation posed in a domain containing a large number of polygonal perforations, we propose a low-dimensional coarse approximation space based on a coarse polygonal partitioning of the domain. Similarly to other multiscale…

Numerical Analysis · Mathematics 2024-04-17 Miranda Boutilier , Konstantin Brenner , Victorita Dolean

We describe a compatible finite element discretisation for the shallow water equations on the rotating sphere, concentrating on integrating consistent upwind stabilisation into the framework. Although the prognostic variables are velocity…

Numerical Analysis · Mathematics 2018-10-17 J. Shipton , T. H. Gibson , C. J. Cotter

The paper presents a general strategy to solve ordinary differential equations (ODE), where some coefficient depend on the spatial variable and on additional random variables. The approach is based on the application of a recently developed…

Numerical Analysis · Mathematics 2019-07-17 Maximilian Bochmann , Lutz Kämmerer , Daniel Potts

We propose a new class of semi-implicit methods for solving nonlinear fractional differential equations and study their stability. Several versions of our new schemes are proved to be unconditionally stable by choosing suitable parameters.…

Numerical Analysis · Mathematics 2018-08-14 Fanhai Zeng , Ian Turner , Kevin Burrage , George Em Karniadakis

We propose a parallel algorithm for the numerical solution of a class of second order semi-linear equations coming from stochastic optimal control problems, by means of a dynamic domain decomposition technique. The new method is an…

Numerical Analysis · Mathematics 2016-02-11 Simone Cacace , Maurizio Falcone

We present a structure-preserving Eulerian algorithm for solving $L^2$-gradient flows and a structure-preserving Lagrangian algorithm for solving generalized diffusions. Both algorithms employ neural networks as tools for spatial…

Numerical Analysis · Mathematics 2024-04-16 Ziqing Hu , Chun Liu , Yiwei Wang , Zhiliang Xu

We highlight some recent new delevelopments concerning the sparse representation of possibly high-dimensional functions exhibiting strong anisotropic features and low regularity in isotropic Sobolev or Besov scales. Specifically, we focus…

Numerical Analysis · Mathematics 2014-09-30 Wolfgang Dahmen , Chunyan Huang , Gitta Kutyniok , Wang-Q Lim , Christoph Schwab , Gerrit Welper

We aim at the development and analysis of the numerical schemes for approximately solving the backward diffusion-wave problem, which involves a fractional derivative in time with order $\alpha\in(1,2)$. From terminal observations at two…

Numerical Analysis · Mathematics 2021-09-16 Zhengqi Zhang , Zhi Zhou

Spectral clustering and its extensions usually consist of two steps: (1) constructing a graph and computing the relaxed solution; (2) discretizing relaxed solutions. Although the former has been extensively investigated, the discretization…

Machine Learning · Computer Science 2023-10-20 Hongyuan Zhang , Xuelong Li

In this paper, we propose Fourier pseudospectral methods to solve the variable-order space fractional wave equation and develop an accelerated matrix-free approach for its effective implementation. In constant-order cases, our methods can…

Numerical Analysis · Mathematics 2024-02-06 Yanzhi Zhang , Xiaofei Zhao , Shiping Zhou

Several problems in magnetically confined fusion, such as the computation of exterior vacuum fields or the decomposition of the total magnetic field into separate contributions from the plasma and the external sources, are best formulated…

Numerical Analysis · Mathematics 2019-11-25 Dhairya Malhotra , Antoine J. Cerfon , Michael O'Neil , Evan Toler

This work extends the concepts of algebraic flux correction and convex limiting to continuous high-order Bernstein finite element discretizations of scalar hyperbolic problems. Using an array of adjustable diffusive fluxes, the standard…

Numerical Analysis · Mathematics 2020-04-22 Dmitri Kuzmin , Manuel Quezada de Luna