Journée Algèbre Linéaire à Amiens

Liste des Contributions

6. A class of nonlinear acceleration techniques based on Krylov subspaces

Yousef Saad

17/03/2025 10:10

There has been a surge of interest in recent years in general-purpose
`acceleration' methods that take a sequence of vectors converging to the limit
of a fixed point iteration, and produce from it a faster converging sequence. A
prototype of these methods that attracted much attention recently is the
Anderson Acceleration (AA) procedure. We introduce the...

2. Convergence of GMRES accelerated by deflation and preconditioning

Nicole Spillane

17/03/2025 11:00

This is joint work with Daniel Szyld (Temple University)

We present new convergence bounds for weighted, preconditioned, and deflated GMRES applied to non-Hermitian linear systems. These bounds are given for the case when the Hermitian part of the coefficient matrix is positive definite, the preconditioner is Hermitian positive definite, and the weight is equal to the preconditioner. The...

5. Perturbations of functions of matrices and applications to density functional theory

Antoine Levitt

17/03/2025 14:00

3. Enhanced stabilization strategies for some linearized PDEs

Youcef Mammeri

17/03/2025 14:50

Stabilizing linearized partial differential equations (PDEs) is a fundamental challenge in numerical analysis and control theory. In this talk, we present advanced strategies for enhancing the stability of linearized PDEs. We begin by reminding the concept of linear instability, illustrated through the example of the Klein-Gordon equation. Next, we introduce an optimal stabilization approach,...

4. Continuous optimization strategies for inverse structured matrix problems with prescribed spectrum

Marcos Raydan

17/03/2025 16:00

The talk will consider several continuous optimization schemes to solve inverse structured symmetric matrix problems with prescribed spectrum. Some entries in the desired matrix are assigned in advance and cannot be altered, and some others should be nonzero. The rest of the entries are free. The reconstructed matrix must satisfy these requirements and its eigenvalues must be the given ones....