Cerfacs Enter the world of high performance ...

Sparse Days Meeting 2006 at CERFACS

Sparse Days Meeting 2006 at CERFACS


June 15th-16th 2006

A two-day meeting on sparse matrix matters at CERFACS, Toulouse, France, June 15th-16th, 2006.

After the excitement of hosting CSC’05 last year, we return to our normal pattern of holding our regular meeting “Sparse Days at CERFACS”. This meeting will start mid-morning on Thursday June 15th and finish mid-afternoon on the 16th. The main theme this year will be on “optimization”.



Programme of Thursday, June15th

Session on constrained optimization

10.15 – 10.45 : M. Saunders : *The LUSOL algorithm*

11.15 – 11.45 : N. Gould : Finding a well-centred point for a set of polyhedral constraints

11.45 – 12.15 : J. Hall : Parallel matrix inversion for the revised simplex method – A study

12.15 – 12.45 : C. Cartis : A new perspective on the complexity of interior point methods for linear programming


Session on unconstrained optimization

14.30 – 15.00 : J.D. Muller : Simultaneous time-stepping methods for optimal design

15.00 – 15.30 : A. Sartenaer : Trust-region algorithms for multilevel optimization

15.30 – 16.00 : C. Sainvitu : Use of approximate derivatives in the filter-trust-region method for unconstrained optimization


Session on data assimilation

16.00 – 16.30 : N.K. Nichols : Using model reduction in Gauss-Newton optimization with applications to data assimilation

17.00 – 17.30 : J. Tshimanga : On some preconditioning techniques for linear least-squares problems with multiple right-hand sides

17.30 – 18.00 : G. Desroziers : Large least-squares problems in Meteorology


Poster session

M. Rojas : A Comparison of Methods for the Large-Scale Trust-Region Subproblem

Programme of Friday, June 16th

Session on iterative methods for linear systems

09.15 – 09.45 : M. Arioli : A note on GMRES preconditioned by a perturbed $ LDL^T$ decomposition with static pivoting

09.45 – 10.15 : S. Dollar : Implicit factorization constraint preconditioners and permutations

10.15 – 10.45 : S. MacLachlan : Greedy strategies for multilevel partitioning


Session on sparse techniques

11.15 – 11.45 : G. Gundersen : Sparsity in Higher Order Methods in Optimization

11.45 – 12.15 : A. Pothen : The Optimal Computation of Hessians in Optimization

12.15 – 12.45 : Ph. L. Toint : Exploiting sparsity in optimization algorithms


Session on derivative free optimization

14.30 – 15.00 : M. Garcia : *Neuronal networks for derivative free optimization*

15.00 – 15.30 : M. Sosonkina : Performance Studies of a Parallel Global Search on System X


Session on sparse solver

15.30 – 16.00 : T. Slavova : *Efficient triangular solution in sparse out-of-core solvers*

Adobe_PDF_file_icon_24x24 List of participants


NextSim General Assembly and TC meeting

CERFACS |  16 September 2021

The General Assembly and TC Meeting took place on 15-16 September 2021. CERFACS is involved in the NextSim project (). The primary objective is to increase the capabilities of Computational Fluid Dynamics tools on extreme-scale parallel computing platforms for aeronautical design. This project has received funding from the European High-Performance Computing Joint Undertaking (JU) under grant agreement N° 956104. The JU receives support from the European Union’s Horizon 2020 research and innovation programme and Spain, France, Germany. This project has received funding from the Agence Nationale de la Recherche (ANR) under grant agreement N° ANR-20-EHPC-0002-02. For more information, please visit Read more

Sophie Valcke from Cerfacs co-authored a new book on atmosphere-ocean modelling

CERFACS |  18 August 2021

new book "Atmosphere-Ocean Modelling - Couling and Couplers” by Prof. Carlos R Mechoso, Prof. Soon-Il An and Dr Sophie Valcke has just been published by World Scientific. The present book fills a void in the current literature by presenting a basic and yet rigorous treatment of how the models of the atmosphere and the ocean are put together into a coupled system. Details are available at  Abstract: Coupled atmosphere-ocean models are at the core of numerical climate models. There is an extraordinarily broad class of coupled atmosphere-ocean models ranging from sets of equations that can be solved analytically to highly detailed representations of Nature requiring the most advanced computers for execution. The models are applied to subjects including the conceptual understanding of Earth’s climate, predictions that support human activities in a variable climate, and projections aimed to prepare society for climate change. The present book fills a void in the current literature by presenting a basic and yet rigorous treatment of how the models of the atmosphere and the ocean are put together into a coupled system. The text of the book is divided into chapters organized according to complexity of the components that are coupled. Two full chapters are dedicated to current efforts on the development of generalist couplers and coupling methodologies all over the worldRead more