Intervenant: Hassane Sadok (LMPA)
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 Titre: New  results about GMRES convergence
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Résumé
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   We consider two Krylov subspace methods for solving linear 
systems,which are the Minimal Residual method  and the Orthogonal 
Residual method. These two methods are studied without refering to any 
algorithms. By using a matrix approach, we give the residual norm of 
these two methods in terms of Krylov matrix, and the relationship 
between there two norms.

  In this talk we will consider the following points :

* What properties of the matrix coefficient govern convergence?
* How describe the convergence of GMRES for normal matrices?
* Comparison between the polynomial and the matrix approach.
* how to derive the optimal bounds?