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20142026
most citedProvably Optimal Parallel Transport Sweeps on Semi-Structured Grids

43 citations · 97 across the 20 of their papers we have counts for

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18 papers · 1 filter

math.NA2026

Convergence Analysis of Block Newton Methods for 1D Shallow Neural Network Approximation

Zhiqiang Cai, Anastassia Doktorova, Robert D. Falgout +1

This paper analyzes local convergence of the block Newton (BN) method introduced in [5, 6] for one-dimensional shallow neural network approximation to functions and diffusion-react…

math.NA2026

Nodal Coarsening and Approximate Ideal Interpolation for H(curl) in Algebraic Multigrid

Taoli Shen, James Brannick, Robert Falgout +2

We propose an approximate interpolation construction and a practical coarsening algorithm for algebraic multigrid (AMG) method when applied to H(curl) problems. Building on the gen…

math.NA2026

Linear Systems and Eigenvalue Problems: Open Questions from a Simons Workshop

Noah Amsel, Yves Baumann, Paul Beckman +33

This document presents a series of open questions arising in matrix computations, i.e., the numerical solution of linear algebra problems. It is a result of working groups at the w…

math.NA2025

Nodal AMG Coarsening and Interpolation for PDE Systems

James Brannick, Robert Falgout, Karsten Kahl +2

We present an approach to constructing a practical coarsening algorithm and interpolation operator for the algebraic multigrid (AMG) method, tailored towards systems of partial dif…

math.NA2024★ 1 cited

Parallel-in-time solution of hyperbolic PDE systems via characteristic-variable block preconditioning

O. A. Krzysik, H. De Sterck, R. D. Falgout +1

We consider the parallel-in-time solution of hyperbolic partial differential equation (PDE) systems in one spatial dimension, both linear and nonlinear. In the nonlinear setting, t…

math.NA2024

Efficient Shallow Ritz Method For 1D Diffusion-Reaction Problems

Zhiqiang Cai, Anastassia Doktorova, Robert D. Falgout +1

This paper studies the shallow Ritz method for solving one-dimensional diffusion-reaction problems. The method is capable of improving the order of approximation for non-smooth pro…

math.NA2024★ 1 cited

Efficient Shallow Ritz Method For 1D Diffusion Problems

Zhiqiang Cai, Anastassia Doktorova, Robert D. Falgout +1

This paper studies the shallow Ritz method for solving the one-dimensional diffusion problem. It is shown that the shallow Ritz method improves the order of approximation dramatica…

math.NA2024

Parallel-in-time solution of scalar nonlinear conservation laws

O. A. Krzysik, H. De Sterck, R. D. Falgout +1

We consider the parallel-in-time solution of scalar nonlinear conservation laws in one spatial dimension. The equations are discretized in space with a conservative finite-volume m…

math.NA2022

Efficient multigrid reduction-in-time for method-of-lines discretizations of linear advection

H. De Sterck, R. D. Falgout, O. A. Krzysik +1

Parallel-in-time methods for partial differential equations (PDEs) have been the subject of intense development over recent decades, particularly for diffusion-dominated problems.…

math.NA2022

Multigrid Reduction in Time for Chaotic Dynamical Systems

David A. Vargas, Robert D. Falgout, Stefanie Günther +1

As CPU clock speeds have stagnated and high performance computers continue to have ever higher core counts, increased parallelism is needed to take advantage of these new architect…

math.NA2022

A New Semi-Structured Algebraic Multigrid Method

Victor A. Paludetto Magri, Robert D. Falgout, Ulrike M. Yang

Multigrid methods are well suited to large massively parallel computer architectures because they are mathematically optimal and display excellent parallelization properties. Since…

math.NA2022

Fast multigrid reduction-in-time for advection via modified semi-Lagrangian coarse-grid operators

H. De Sterck, R. D. Falgout, O. A. Krzysik

Many iterative parallel-in-time algorithms have been shown to be highly efficient for diffusion-dominated partial differential equations (PDEs), but are inefficient or even diverge…

math.NA2022★ 1 cited

Toward Parallel in Time for Chaotic Dynamical Systems

David A. Vargas, Robert D. Falgout, Stefanie Günther +1

As CPU clock speeds have stagnated, and high performance computers continue to have ever higher core counts, increased parallelism is needed to take advantage of these new architec…

math.NA2019★ 32 cited

Optimizing multigrid reduction-in-time (MGRIT) and Parareal coarse-grid operators for linear advection

Hans De Sterck, Robert D. Falgout, Stephanie Friedhoff +2

Parallel-in-time methods, such as multigrid reduction-in-time (MGRIT) and Parareal, provide an attractive option for increasing concurrency when simulating time-dependent PDEs in m…

math.NA2018

Multilevel convergence analysis of multigrid-reduction-in-time

Andreas Hessenthaler, Ben S. Southworth, David Nordsletten +3

This paper presents a multilevel convergence framework for multigrid-reduction-in-time (MGRIT) as a generalization of previous two-grid estimates. The framework provides a priori u…

math.NA2017★ 2 cited

Optimal interpolation and Compatible Relaxation in Classical Algebraic Multigrid

James Brannick, Fei Cao, Karsten Kahl +2

In this paper, we consider a classical form of optimal algebraic multigrid (AMG) interpolation that directly minimizes the two-grid convergence rate and compare it with the so-call…

math.NA2015★ 7 cited

Robust A Posteriori Error Estimation for Finite Element Approximation to H(curl) Problem

Zhiqiang Cai, Shuhao Cao, Rob Falgout

In this paper, we introduce a novel a posteriori error estimator for the conforming finite element approximation to the H(curl) problem with inhomogeneous media and with the right-…

math.NA2014

Div First-Order System LL* (FOSLL*) for Second-Order Elliptic Partial Differential Equations

Zhiqiang Cai, Rob Falgout, Shun Zhang

The first-order system LL* (FOSLL*) approach for general second-order elliptic partial differential equations was proposed and analyzed in [10], in order to retain the full efficie…