Results 11 to 20 of about 1,193 (178)

Multigrid methods for improving the variational data assimilation in numerical weather prediction [PDF]

Tellus: Series A, Dynamic Meteorology and Oceanography, 2014
Two conditions are needed to solve numerical weather prediction models: initial condition and boundary condition. The initial condition has an especially important bearing on the model performance.
Youn-Hee Kang, Do Young Kwak, Kyungjeen Park   +2 more
doaj   +1 more source

Nonlinear Multigrid Implementation for the Two-Dimensional Cahn–Hilliard Equation

Mathematics, 2020
We present a nonlinear multigrid implementation for the two-dimensional Cahn−Hilliard (CH) equation and conduct detailed numerical tests to explore the performance of the multigrid method for the CH equation.
Chaeyoung Lee, Darae Jeong, Junxiang Yang, Junseok Kim   +3 more
doaj   +1 more source

An Aggregation-Based Algebraic Multigrid Method with Deflation Techniques and Modified Generic Factored Approximate Sparse Inverses

Mathematics, 2023
In this paper, we examine deflation-based algebraic multigrid methods for solving large systems of linear equations. Aggregation of the unknown terms is applied for coarsening, while deflation techniques are proposed for improving the rate of convergence.
Anastasia A. Natsiou, George A. Gravvanis, Christos K. Filelis-Papadopoulos, Konstantinos M. Giannoutakis   +3 more
doaj   +1 more source

A multigrid discretization scheme based on the shifted inverse iteration for the Steklov eigenvalue problem in inverse scattering

Open Mathematics, 2023
Numerical methods for computing Steklov eigenvalues have attracted the attention of academia for their important physical background and wide applications.
Xie Jiali, Bi Hai
doaj   +1 more source

An extrapolation full multigrid algorithm combined with fourth-order compact scheme for convection–diffusion equations

Advances in Difference Equations, 2018
In this paper, we propose an extrapolation full multigrid (EXFMG) algorithm to solve the large linear system arising from a fourth-order compact difference discretization of two-dimensional (2D) convection diffusion equations.
Ming Li, Zhoushun Zheng, Kejia Pan
doaj   +1 more source

Combining p-multigrid and Multigrid Reduction in Time methods to obtain a scalable solver for Isogeometric Analysis

SN Applied Sciences, 2022
Article Highlights The use of a p-multigrid method significantly reduces the CPU timings for higher values of the spline degree. The Multigrid Reduction in Time method shows both strong and weak scalability up to 2048 cores.
Roel Tielen, Matthias Möller, Cornelis Vuik   +2 more
doaj   +1 more source

XAMG: A library for solving linear systems with multiple right-hand side vectors

SoftwareX, 2021
This paper presents the XAMG library for solving large sparse systems of linear algebraic equations with multiple right-hand side vectors. The library specializes, but is not limited, to the solution of linear systems obtained from the discretization of ...
Boris Krasnopolsky, Alexey Medvedev
doaj   +1 more source

Application of multigrid NLS-4DVar in radar radial velocity data assimilation with WRF-ARW

Atmospheric and Oceanic Science Letters, 2019
The nonlinear least-squares four-dimensional variational assimilation (NLS-4DVar) method introduced here combines the merits of the ensemble Kalman filter and 4DVar assimilation methods.
Lu ZHANG, Xiangjun TIAN, Hongqin ZHANG
doaj   +1 more source

A numerical solution of parabolic quasi-variational inequality nonlinear using Newton-multigrid method [PDF]

Iranian Journal of Numerical Analysis and Optimization
In this article, we apply three numerical methods to study the L∞-convergence of the Newton-multigrid method for parabolic quasi-variational inequalities with a nonlinear right-hand side.
M. Bahi, M. Beggas, N. Nesba, A. Imtiaz
doaj   +1 more source

Surrogate modeling of fluid dynamics with a multigrid inspired neural network architecture

Machine Learning with Applications, 2021
Algebraic or geometric multigrid methods are commonly used in numerical solvers as they are a multi-resolution method able to handle problems with multiple scales.
Quang Tuyen Le, Chinchun Ooi
doaj   +1 more source