2 papers
math.NA2022
Smoothing analysis of two robust multigrid methods for elliptic optimal control problems
Yunhui He, Jun Liu
In this paper we study and compare two multigrid relaxation schemes with coarsening by two, three, and four for solving elliptic sparse optimal control problems with control constr…
math.NA2020
A ROM-accelerated parallel-in-time preconditioner for solving all-at-once systems from evolutionary PDEs
Jun Liu, Zhu Wang
In this paper we propose to use model reduction techniques for speeding up the diagonalization-based parallel-in-time (ParaDIAG) preconditioner, for iteratively solving all-at-once…