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We present a novel accelerated primal-dual (APD) method for solving a class of deterministic and stochastic saddle point problems (SPP). The basic idea of this algorithm is to incorporate a multi-step acceleration scheme into the…

Optimization and Control · Mathematics 2013-09-24 Yunmei Chen , Guanghui Lan , Yuyuan Ouyang

Solving the linear elasticity and Stokes equations by an optimal domain decomposition method derived algebraically involves the use of non standard interface conditions. The one-level domain decomposition preconditioners are based on the…

Numerical Analysis · Mathematics 2018-04-23 Gabriel R. Barrenechea , Michał Bosy , Victorita Dolean

In this work, we consider fracture propagation in nearly incompressible and (fully) incompressible materials using a phase-field formulation. We use a mixed form of the elasticity equation to overcome volume locking effects and develop a…

Numerical Analysis · Mathematics 2022-02-10 Timo Heister , Katrin Mang , Thomas Wick

Preconditioning has long been a staple technique in optimization, often applied to reduce the condition number of a matrix and speed up the convergence of algorithms. Although there are many popular preconditioning techniques in practice,…

Optimization and Control · Mathematics 2022-11-08 Zhaonan Qu , Wenzhi Gao , Oliver Hinder , Yinyu Ye , Zhengyuan Zhou

The aim of this paper is to solve large-and-sparse linear Semidefinite Programs (SDPs) with low-rank solutions. We propose to use a preconditioned conjugate gradient method within second-order SDP algorithms and introduce a new efficient…

Optimization and Control · Mathematics 2021-05-19 Soodeh Habibi , Arefeh Kavand , Michal Kocvara , Michael Stingl

In this paper we propose two variants of the substructuring preconditioner for solving three-dimensional elliptic-type equations with strongly discontinuous coefficients. In the new preconditioners, we use the simplest coarse solver…

Numerical Analysis · Mathematics 2016-11-29 Qiya Hu , Shaoliang Hu

We propose an augmented Lagrangian-based preconditioner to accelerate the convergence of Krylov subspace methods applied to linear systems of equations with a block three-by-three structure such as those arising from mixed finite element…

Numerical Analysis · Mathematics 2023-10-26 Fatemeh P. A. Beik , Michele Benzi

The paper arXiv:1804.11290 contains well-posedness and regularity results for a system of evolutionary operator equations having the structure of a Cahn-Hilliard system. The operators appearing in the system equations were fractional…

Analysis of PDEs · Mathematics 2018-12-17 Pierluigi Colli , Gianni Gilardi , Jürgen Sprekels

A new preconditioner based on a block $LDU$ factorization with algebraic multigrid subsolves for scalability is introduced for the large, structured systems appearing in implicit Runge-Kutta time integration of parabolic partial…

Numerical Analysis · Mathematics 2021-01-15 Md Masud Rana , Victoria E. Howle , Katharine Long , Ashley Meek , William Milestone

Phase-field fracture models lead to variational problems that can be written as a coupled variational equality and inequality system. Numerically, such problems can be treated with Galerkin finite elements and primal-dual active set…

Numerical Analysis · Mathematics 2020-05-04 Daniel Jodlbauer , Ulrich Langer , Thomas Wick

This paper introduces a new sweeping preconditioner for the iterative solution of the variable coefficient Helmholtz equation in two and three dimensions. The algorithms follow the general structure of constructing an approximate $LDL^t$…

Numerical Analysis · Mathematics 2010-08-03 Björn Engquist , Lexing Ying

In this paper, we develop two classes of robust preconditioners for the structure-preserving discretization of the incompressible magnetohydrodynamics (MHD) system. By studying the well-posedness of the discrete system, we design block…

Numerical Analysis · Mathematics 2016-06-22 Yicong Ma , Kaibo Hu , Xiaozhe Hu , Jinchao Xu

Model predictive control (MPC) for linear dynamical systems requires solving an optimal control structured quadratic program (QP) at each sampling instant. This paper proposes a primal active-set strategy (PRESAS) for the efficient solution…

Optimization and Control · Mathematics 2020-07-14 Rien Quirynen , Stefano Di Cairano

We consider saddle point problems which objective functions are the average of $n$ strongly convex-concave individual components. Recently, researchers exploit variance reduction methods to solve such problems and achieve linear-convergence…

Machine Learning · Computer Science 2019-09-17 Luo Luo , Cheng Chen , Yujun Li , Guangzeng Xie , Zhihua Zhang

In this work, we propose a novel diagonalization-based preconditioner for the all-at-once linear system arising from the optimal control problem of parabolic equations. The proposed preconditioner is constructed based on an…

Numerical Analysis · Mathematics 2025-07-01 Sean Y. Hon , Po Yin Fung , Xue-lei Lin

The Helmholtz wave scattering problem by screens in 2D can be recast into first-kind integral equations which lead to ill-conditioned linear systems after discretization. We introduce two new preconditioners, in the form of square-roots of…

Numerical Analysis · Mathematics 2019-12-03 François Alouges , Martin Averseng

We propose a neural network framework for solving stationary linear transport equations with inflow boundary conditions. The method represents the solution using a neural network and imposes the boundary condition via a Lagrange multiplier,…

Numerical Analysis · Mathematics 2025-07-29 Charalambos Makridakis , Aaron Pim , Tristan Pryer , Nikolaos Rekatsinas

Primal-dual methods for solving convex optimization problems with functional constraints often exhibit a distinct two-stage behavior. Initially, they converge towards a solution at a sublinear rate. Then, after a certain point, the method…

Optimization and Control · Mathematics 2026-02-12 Mateo Díaz , Pedro Izquierdo Lehmann , Haihao Lu , Jinwen Yang

We provide an overview of primal-dual algorithms for nonsmooth and non-convex-concave saddle-point problems. This flows around a new analysis of such methods, using Bregman divergences to formulate simplified conditions for convergence.

Optimization and Control · Mathematics 2021-08-03 Tuomo Valkonen

We consider the hydrodynamics of an incompressible fluid on a 2D periodic domain. There exists a family of stationary solutions with vorticity given by $\Omega^*=\alpha\cos (\mathbf{p} \cdot \mathbf{x} )+\beta \sin (\mathbf{p} \cdot…

Dynamical Systems · Mathematics 2016-08-26 Joachim Worthington , Holger R. Dullin , Robert Marangell