Results 61 to 70 of about 81,041 (236)

GMRES for oscillatory matrix-valued differential equations [PDF]

, 2009
We investigate the use of Krylov subspace methods to solve linear, oscillatory ODEs. When we apply a Krylov subspace method to a properly formulated equation, we retain the asymptotic accuracy of the asymptotic expansion whilst converging to the exact ...
Olver, Sheehan
core  

Coupled Clustering in Hierarchical Matrices for the Oseen Problem

International Journal for Numerical Methods in Fluids, Volume 98, Issue 6, Page 751-765, June 2026.
Fluid flow problems can be modelled by the Navier‐Stokes or, after linearization, by the Oseen equations. Their discretization results in linear systems in saddle point form which are typically very large and need to be solved iteratively. We propose a novel block structure for hierarchical matrices which is then used to build preconditioners for the ...
Jonas Grams, Sabine Le Borne
wiley   +1 more source

A Preconditioned Majorization‐Minimization Method for ℓ2$$ {\ell}^2 $$‐ℓq$$ {\ell}^q $$ Minimization

Numerical Linear Algebra with Applications, Volume 33, Issue 3, June 2026.
ABSTRACT The need to minimize a linear combination of an expression that involves an ℓq$$ {\ell}^q $$‐norm of a linear transformation of the computed solution and the ℓ2$$ {\ell}^2 $$‐norm of the residual error arises in image restoration as well as in statistics.
A. Buccini, M. Donatelli, M. Ratto, L. Reichel   +3 more
wiley   +1 more source

Simultaneous Inversion for Underactuated Mechanical Systems with Servo‐Constraints

Proceedings in Applied Mathematics and Mechanics, Volume 26, Issue 2, June 2026.
ABSTRACT The dynamic inversion of underactuated mechanical systems can be formulated in the servo‐constraint framework using a set of differential‐algebraic equations (DAEs). In case of a high differentiation index, the inversion‐based feedforward control design poses significant challenges.
Tengman Wang
wiley   +1 more source

Iterative Krylov Subspace Methods for Linear Port‐Hamiltonian Systems

Proceedings in Applied Mathematics and Mechanics, Volume 26, Issue 2, June 2026.
ABSTRACT In this work, we present a structure‐preserving Krylov subspace iteration scheme for solving the equation systems that arise from the Gauss integration of linear energy‐conserving and dissipative differential systems (e.g., Poisson systems, gradient systems, and port‐Hamiltonian systems).
Stefan Maier, Nicole Marheineke
wiley   +1 more source

Explicit‐Implicit Material Point Method for Dense Granular Flows With a Novel Regularized µ(I) Model

International Journal for Numerical and Analytical Methods in Geomechanics, Volume 50, Issue 7, Page 3256-3273, May 2026.
ABSTRACT The material point method (MPM) is widely employed to simulate granular flows. Although explicit time integration is favored in most current MPM implementations for its simplicity, it cannot rigorously incorporate the incompressible µ(I)‐rheology, an efficient model ubiquitously adopted in other particle‐based numerical methods. While operator‐
Hang Feng, Zhen‐Yu Yin
wiley   +1 more source

Forward and Adjoint Calculations of Gravitational Potential in Heterogeneous, Aspherical Planets

Earth and Space Science, Volume 13, Issue 5, May 2026.
Abstract We have developed a computational package for the calculation of numerically exact internal and external gravitational potential, its functional derivatives and sensitivity kernels, in an aspherical, heterogeneous planet. We detail our implementation, utilizing a transformation of the Poisson equation into a spherical reference domain, as well
Alex D. C. Myhill, Matthew A. Maitra, David Al‐Attar   +2 more
wiley   +1 more source

Nonlinear Dynamic Inverse Solution of the Diffusion Problem Based on Krylov Subspace Methods with Spatiotemporal Constraints

Computer Sciences & Mathematics Forum
In this work, we propose a nonlinear dynamic inverse solution to the diffusion problem based on Krylov Subspace Methods with spatiotemporal constraints. The proposed approach is applied by considering, as a forward problem, a 1D diffusion problem with a ...
Luis Fernando Alvarez-Velasquez, Eduardo Giraldo   +1 more
doaj   +1 more source

Circulant preconditioners for mean curvature-based image deblurring problem

Journal of Algorithms & Computational Technology, 2021
The mean curvature-based image deblurring model is widely used to enhance the quality of the deblurred images. However, the discretization of the associated Euler–Lagrange equations produces a nonlinear ill-conditioned system which affects the ...
Shahbaz Ahmad, Faisal Fairag
doaj   +1 more source

Exponential-Krylov methods for ordinary differential equations

, 2014
This paper develops a new class of exponential-type integrators where all the matrix exponentiations are performed in a single Krylov space of low dimension.
Sandu, Adrian, Tranquilli, Paul
core   +1 more source