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Related papers: A fast direct solver for the advection-diffusion e…

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This paper deals with speeding up the convergence of a class of two-step iterative methods for solving linear systems of equations. To implement the acceleration technique, the residual norm associated with computed approximations for each…

Numerical Analysis · Mathematics 2024-04-24 Fatemeh P. A. Beik , Michele Benzi , Mehdi Najafi-Kalyani

We investigate numerical behaviour of a convection diffusion equation with random coefficients by approximating statistical moments of the solution. Stochastic Galerkin approach, turning the original stochastic problem to a system of…

Numerical Analysis · Mathematics 2021-10-19 Pelin Çiloğlu , Hamdullah Yücel

We describe a fast solver for linear systems with reconstructable Cauchy-like structure, which requires O(rn^2) floating point operations and O(rn) memory locations, where n is the size of the matrix and r its displacement rank. The solver…

Numerical Analysis · Mathematics 2021-09-21 Antonio Arico' , Giuseppe Rodriguez

We develop an immersed-boundary approach to modeling reaction-diffusion processes in dispersions of reactive spherical particles, from the diffusion-limited to the reaction-limited setting. We represent each reactive particle with a…

Numerical Analysis · Mathematics 2015-06-16 A. Pal Singh Bhalla , B. E. Griffith , N. A. Patankar , A. Donev

We extend a previously proposed rotation and truncation scheme to optimize quantum Anderson impurity calculations with exact diagonalization [PRB 90, 085102 (2014)] to density-matrix renormalization group (DMRG) calculations. The method…

Strongly Correlated Electrons · Physics 2019-10-02 Y. Lu , X. Cao , P. Hansmann , M. W. Haverkort

We study the long-time asymptotics of prototypical non-linear diffusion equations. Specifically, we consider the case of a non-degenerate diffusivity function that is a (non-negative) polynomial of the dependent variable of the problem. We…

Analysis of PDEs · Mathematics 2020-08-13 Ivan C. Christov , Akif Ibraguimov , Rahnuma Islam

This paper presents a novel stochastic method for modeling the transport of Delayed Neutron Precursors (DNPs) in liquid nuclear fuel. The method incorporates advection and diffusion effects into the Monte Carlo solution of the neutron…

Computational Physics · Physics 2025-01-27 Mathis Caprais , Daniele Tomatis

High-order derivatives of Green's functions are a key ingredient in Taylor-based fast multipole methods, Barnes-Hut $n$-body algorithms, and quadrature by expansion (QBX). In these settings, derivatives underpin either the formation,…

Computational Engineering, Finance, and Science · Computer Science 2026-04-01 Hirish Chandrasekaran , Andreas Kloeckner

We solve a fractional diffusion equation using a piecewise-constant, discontinuous Galerkin method in time combined with a continuous, piecewise-linear finite element method in space. If there are $N$ time levels and $M$ spatial degrees of…

Numerical Analysis · Mathematics 2016-02-02 William McLean

Diffusion-based inverse algorithms have shown remarkable performance across various inverse problems, yet their reliance on numerous denoising steps incurs high computational costs. While recent developments of fast diffusion ODE solvers…

Computer Vision and Pattern Recognition · Computer Science 2025-10-22 Jiawei Zhang , Ziyuan Liu , Leon Yan , Gen Li , Yuantao Gu

In [Z. Hu, R. Li, and Z. Qiao. Acceleration for microflow simulations of high-order moment models by using lower-order model correction. J. Comput. Phys., 327:225-244, 2016], it has been successfully demonstrated that using lower-order…

Numerical Analysis · Mathematics 2019-05-14 Zhicheng Hu , Guanghui Hu

Diffusion probabilistic models (DPMs) are emerging powerful generative models. Despite their high-quality generation performance, DPMs still suffer from their slow sampling as they generally need hundreds or thousands of sequential function…

Machine Learning · Computer Science 2022-10-17 Cheng Lu , Yuhao Zhou , Fan Bao , Jianfei Chen , Chongxuan Li , Jun Zhu

A steady-state convection-diffusion problem with a small diffusion of order $\mathcal{O}(\varepsilon)$ is considered in a thin three-dimensional graph-like junction consisting of thin cylinders connected through a domain (node) of diameter…

Analysis of PDEs · Mathematics 2022-08-12 Taras A. Mel'nyk , Arsen V. Klevtsovskiy

In this paper we propose a variant of the random coordinate descent method for solving linearly constrained convex optimization problems with composite objective functions. If the smooth part of the objective function has Lipschitz…

Optimization and Control · Mathematics 2013-02-14 Ion Necoara , Andrei Patrascu

In this paper, the exponential B-spline functions are used for the numerical solution of the advection-diffusion equation. Two numerical examples\ related to pure advection in a finitely long channel and the distribution of an initial…

Numerical Analysis · Mathematics 2019-04-01 Melis Zorsahin Gorgulu , Idris Dag

We propose a new model to approximate the wave response of waveguides containing an arbitrary number of small inclusions. The theory is developed to consider any one-dimensional waveguide (longitudinal, flexural, shear, torsional waves or a…

Computational Physics · Physics 2024-05-07 Mario Lázaro , Richard Wiltshaw , Richard Vaughan Craster , Luis M. García-Raffi

We present a very simple and fast algorithm for the numerical solution of viscoplastic flow problems without prior regularisation. Compared to the widespread alternating direction method of multipliers (ADMM / ALG2), the new method features…

Numerical Analysis · Mathematics 2016-09-27 Timm Treskatis , Miguel A. Moyers-Gonzalez , Chris J. Price

In this article, we derive the exact closed-form solution for the displacement in the interior of an elastic half-space due to a buried point force with Heaviside step function time history. It is referred to as the tensor Green's function…

Geophysics · Physics 2025-05-13 Xi Feng , Haiming Zhang

In this paper, we are interested in the propagation of convexity by the strong solution to a one-dimensional Brownian stochastic differential equation with coefficients Lipschitz in the spatial variable uniformly in the time variable and in…

Probability · Mathematics 2023-12-18 Benjamin Jourdain , Gilles Pagès

It is well known that second order linear ordinary differential equations with slowly varying coefficients admit slowly varying phase functions. This observation is the basis of the Liouville-Green method and many other techniques for the…

Numerical Analysis · Mathematics 2022-12-19 James Bremer