English
Related papers

Related papers: Iterative solution and preconditioning for the tan…

200 papers

Inversion of sparse matrices with standard direct solve schemes is robust, but computationally expensive. Iterative solvers, on the other hand, demonstrate better scalability; but, need to be used with an appropriate preconditioner (e.g.,…

Numerical Analysis · Mathematics 2017-09-28 Hadi Pouransari , Pieter Coulier , Eric Darve

We present and analyze a preconditioned conjugate gradient method (PCG) for solving spatial network problems. Primarily, we consider diffusion and structural mechanics simulations for fiber based materials, but the methodology can be…

Numerical Analysis · Mathematics 2022-07-18 Morgan Görtz , Fredrik Hellman , Axel Målqvist

Linear solvers are major computational bottlenecks in a wide range of decision support and optimization computations. The challenges become even more pronounced on heterogeneous hardware, where traditional sparse numerical linear algebra…

Computational Engineering, Finance, and Science · Computer Science 2024-01-26 Kasia Świrydowicz , Nicholson Koukpaizan , Maksudul Alam , Shaked Regev , Michael Saunders , Slaven Peleš

Tensor networks are a class of algorithms aimed at reducing the computational complexity of high-dimensional problems. They are used in an increasing number of applications, from quantum simulations to machine learning. Exploiting data…

Numerical Analysis · Mathematics 2024-10-25 Melven Röhrig-Zöllner , Manuel Joey Becklas , Jonas Thies , Achim Basermann

We consider an infinite ferromagnetic nanowire, with an energy functional $E$ with easy-axis in the direction $e_1$ and a constant external magnetic field $H_{ext} = h_0 e_1$ along the same direction. The evolution of its magnetization is…

Analysis of PDEs · Mathematics 2025-06-27 Guillaume Ferriere

The complex Ginzburg Landau equation (CGLE) is a ubiquitous model for the evolution of slowly varying wave packets in nonlinear dissipative media. A front (shock) is a transient layer between a plane-wave state and a zero background. We…

Pattern Formation and Solitons · Physics 2015-05-27 Tat Leung Yee , Alan Cheng Hou Tsang , Boris Malomed , Kwok Wing Chow

This work presents a rigorous prediction of the effective equations governing the paramagnetic-ferromagnetic phase transition in a perforated three-dimensional body. Assuming a periodic distribution of perforations, we investigate the…

Analysis of PDEs · Mathematics 2025-08-29 Catherine Choquet , Mohamed Ouhadan , Mouhcine Tilioua

By applying the linearly implicit conservative difference scheme proposed in [D.-L. Wang, A.-G. Xiao, W. Yang. J. Comput. Phys. 2014;272:670-681], the system of repulsive space fractional coupled nonlinear Schr\"odinger equations leads to a…

Numerical Analysis · Mathematics 2024-10-18 Fei-Yan Zhang , Xi Yang , Chao Chen

The Interior-Point Methods are a class for solving linear programming problems that rely upon the solution of linear systems. At each iteration, it becomes important to determine how to solve these linear systems when the constraint matrix…

Optimization and Control · Mathematics 2024-04-18 Catalina J. Villalba , Aurelio R. L. Oliveira

We present efficient numerical methods for the simulation of small magnetization oscillations in three-dimensional micromagnetic systems. Magnetization dynamics is described by the Landau-Lifshitz-Gilbert (LLG) equation, linearized in the…

Computational Physics · Physics 2023-01-18 Massimiliano d'Aquino , Riccardo Hertel

In several geophysical applications, such as full waveform inversion and data modelling, we are facing the solution of inhomogeneous Helmholtz equation. The difficulties of solving the Helmholtz equa- tion are two fold. Firstly, in the case…

Geophysics · Physics 2017-12-27 Nasser Kazemi

In recent years, there has been a renewed interest in preconditioning for multilevel Toeplitz systems, a research field that has been extensively explored over the past several decades. This work introduces novel preconditioning strategies…

Numerical Analysis · Mathematics 2024-10-01 Sean Y. Hon , Congcong Li , Rosita L. Sormani , Rolf Krause , Stefano Serra-Capizzano

The multigrid-reduction-in-time (MGRIT) technique has proven to be successful in achieving higher run-time speedup by exploiting parallelism in time. The goal of this article is to develop and analyze a MGRIT algorithm, using FCF-relaxation…

Numerical Analysis · Mathematics 2021-02-10 Xiaoqiang Yue , Kejia Pan , Jie Zhou , Zhifeng Weng , Shi Shu , Juan Tang

We present a compatible finite element discretisation for the vertical slice compressible Euler equations, at next-to-lowest order (i.e., the pressure space is bilinear discontinuous functions). The equations are numerically integrated in…

Numerical Analysis · Mathematics 2023-06-26 C. J. Cotter , J. Shipton

A thermo-elastoplastic finite element approach is used to perform the simulation of a laser beam welding (LBW) process. This results in a nonlinear, nonsymmetric saddle point multiphysics system, for which the nonlinearity is handled via…

Numerical Analysis · Mathematics 2025-02-28 Tommaso Bevilacqua , Axel Klawonn , Martin Lanser

Magnetic particle imaging (MPI) is a tracer-based technique for medical imaging where the tracer consists of ironoxide nanoparticles. The key idea is to measure the particle response to a temporally changing external magnetic field to…

Analysis of PDEs · Mathematics 2019-09-09 Barbara Kaltenbacher , Tram Thi Ngoc Nguyen , Anne Wald , Thomas Schuster

Mechanical metamaterials feature engineered microstructures designed to exhibit exotic, and often counter-intuitive, effective behaviour. Such a behaviour is often achieved through instability-induced transformations of the underlying…

Computational Engineering, Finance, and Science · Computer Science 2020-09-04 S. E. H. M. van Bree , O. Rokoš , R. H. J. Peerlings , M. Doškář , M. G. D. Geers

A structured preconditioned conjugate gradient (PCG) solver is developed for the Newton steps in second-order methods for a class of constrained network optimal control problems. Of specific interest are problems with discrete-time dynamics…

Systems and Control · Electrical Eng. & Systems 2020-10-13 Armaghan Zafar , Michael Cantoni , Farhad Farokhi

We prove well-posedness of time-dependent Ginzburg--Landau system in a nonconvex polygonal domain, and decompose the solution as a regular part plus a singular part. We see that the magnetic potential is not in $H^1$ in general, and the…

Numerical Analysis · Mathematics 2014-10-16 Buyang Li , Zhimin Zhang

We present a preconditioning method for the linear systems arising from the boundary element discretization of the Laplace hypersingular equation on a $2$-dimensional triangulated surface $\Gamma$ in $\mathbb{R}^3$. We allow $\Gamma$ to…

Numerical Analysis · Mathematics 2023-10-16 Martin Averseng , Xavier Claeys , Ralf Hiptmair