Observation thinning in data assimilation computations

Autor: Serge Gratton, Monserrat Rincon-Camacho, Ehouarn Simon, Philippe L. Toint

Publikováno v: EURO Journal on Computational Optimization, Vol 3, Iss 1, Pp 31-51 (2015)

We propose to use an observation-thinning method for the efficient numerical solution of large-scale incremental four- dimensional (4D-Var) data assimilation problems. This decomposition is based on exploiting an adaptive hierarchy of the observation

Externí odkaz: https://doaj.org/article/62a298c003384283901627d22f1dae46

An algorithm for the minimization of nonsmooth nonconvex functions using inexact evaluations and its worst-case complexity

Autor: Ehouarn Simon, Philippe L. Toint, Serge Gratton

Publikováno v: Gratton, S, Simon, E & Toint, P 2020, ' An algorithm for the minimization of nonsmooth nonconvex functions using inexact evaluations and its worst-case complexity ', Mathematical Programming, vol. 187, no. 1-2, pp. 1-24 . https://doi.org/10.1007/s10107-020-01466-5
Mathematical Programming, Series A
Mathematical Programming, Series A, Springer, 2020, ⟨10.1007/s10107-020-01466-5⟩

An adaptive regularization algorithm using inexact function and derivatives evaluations is proposed for the solution of composite nonsmooth nonconvex optimization. It is shown that this algorithm needs at most $$O(|\log (\epsilon )|\,\epsilon ^{-2})$

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::ae7993981adb1e2f90e1386ada2a6244
https://doi.org/10.1007/s10107-020-01466-5

Correction: Neural Prediction Model for Transition Onset of a Boundary-Layer in Presence of 2D Surface Defects

Autor: Adrien Rouviere, Lucas Pascal, Fabien Méry, Ehouarn Simon, Serge Gratton

Publikováno v: AIAA SCITECH 2022 Forum.

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_________::a91d6bc117749638b8950a5c17bac0b4
https://doi.org/10.2514/6.2022-1073.c1

A note on inexact inner products in GMRES

Autor: Serge Gratton, Ehouarn Simon, David Titley-Peloquin, Philippe L. Toint

We show to what extent the accuracy of the inner products computed in the GMRES iterative solver can be reduced as the iterations proceed without affecting the convergence rate or final accuracy achieved by the iterates. We bound the loss of orthogon

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::5f3cf4d7bc5f288015ef8857eaa2a298
https://ut3-toulouseinp.hal.science/hal-03637231

A Deep Learning Approach for Estimation of the Nearshore Bathymetry

Autor: Grégoire Abessolo, Bastien Vieuble, Tom Ragonneau, Mahmoud Al Najar, Ehouarn Simon, Erwin Bergsma, Dennis G. Wilson, Benjamin Lavie, Grégoire Thoumyre, Rafael Almar, Guillaume Hugonnard, Laurent Labracherie, Rachid Benshila

Publikováno v: Journal of Coastal Research
Journal of Coastal Research, Coastal Education and Research Foundation, 2020, 95 (sp1), pp.1011-1015. ⟨10.2112/SI95-197.1⟩

Benshila, R.; Thoumyre, G.; Al Najar, M.; Absessolo, G.; Almar, R.; Bergsma, E.; Hugonnard, G.; Labracherie, L.; Lavie, B.; Ragonneau, T.; Simon, E.; Vieuble, B., and Wilson D., 2020. A deep learning approach for estimation of the nearshore bathymetr

Externí odkaz: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::31b298bf581b3a761503bd3066640d17
https://hal.archives-ouvertes.fr/hal-02769859