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4D variational data assimilation for locally nested models: optimality system and preliminary experiments

Laurent Debreu , Ehouarn Simon , Eric Blayo
[Research Report] RR-7675, INRIA. 2011, pp.19
Reports inria-00607177v1

Assimilation de données variationnelle pour des modèles multi-échelles

Ehouarn Simon , Laurent Debreu , Eric Blayo
Colloque national sur l'assimilation de données, May 2006, Toulouse, France
Conference papers hal-00171642v1
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Neural Prediction Model for Transition Onset of a Boundary-Layer in Presence of 2D Surface Defects

Adrien Rouvière , Lucas Pascal , Fabien Méry , Ehouarn Simon , Serge Gratton et al.
22th ONERA-DLR Aerospace Symposium (ODAS 2022), Jun 2022, Hamburg, Germany. pp.1-10
Conference papers hal-03774047v1
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Assimilation variationnelle de données pour des modèles emboîtés

Ehouarn Simon
Modélisation et simulation. Université Joseph-Fourier - Grenoble I, 2007. Français. ⟨NNT : ⟩
Theses tel-00194593v1

Minimizing convex quadratics with variable precision conjugate gradients

Serge Gratton , Ehouarn Simon , David Titley-Peloquin , Philippe Toint
Numerical Linear Algebra with Applications, 2021, 28 (e2337)
Journal articles hal-02959082v1

Observation thinning in data assimilation computations

Serge Gratton , Monserrat Rincon-Camacho , Ehouarn Simon , Philippe Toint
EURO Journal on Computational Optimization, 2015, 3 (1), pp.31-51. ⟨10.1007/s13675-014-0025-4⟩
Journal articles hal-02960628v1
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Multigrid solvers and multigrid preconditioners for the solution of variational data assimilation problems

Laurent Debreu , Emilie Neveu , Ehouarn Simon , François-Xavier Le Dimet , Arthur Vidard et al.
Quarterly Journal of the Royal Meteorological Society, 2016, 142 (694), pp.515-528. ⟨10.1002/qj.2676⟩
Journal articles hal-00874643v1
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Exploiting variable precision in GMRES

Serge Gratton , Ehouarn Simon , David Titley-Peloquin , Philippe Toint
2020
Preprints, Working Papers, ... hal-02943241v1

A Deep Learning Approach for Estimation of the Nearshore Bathymetry

Rachid Benshila , Grégoire Thoumyre , Mahmoud Al Najar , Grégoire Abessolo , Rafael Almar et al.
Journal of Coastal Research, 2020, 95 (sp1), pp.1011-1015. ⟨10.2112/SI95-197.1⟩
Journal articles hal-02769859v1

Issues in making the weakly-constrained 4DVar formulation computationally efficient

Serge Gratton , Selime Gurol , Ehouarn Simon , Philippe Toint
Griewank, Andreas; Reich, Sebastian; Roulstone, Ian; Stuart, Andrew. Mathematical and Algorithmic Aspects of Data Assimilation in the Geosciences, 13 (4), Mathematisches Forschungsinstitut Oberwolfach, pp.2705-2748, 2017, Oberwolfach Reports, ISSN: 1660-8933. ⟨10.4171/OWR/2016/47⟩
Book sections hal-03176447v1

Online tuning of ocean biogeochemical model parameters using ensemble estimation techniques: Application to a one-dimensional model in the North Atlantic

M.E. Gharamti , A. Samuelsen , L. Bertino , Ehouarn Simon , A. Korosov et al.
Journal of Marine Systems, 2017, 168, pp.1-16. ⟨10.1016/j.jmarsys.2016.12.003⟩
Journal articles hal-02960626v1

4D-Variational data assimilation for locally nested numerical models

Ehouarn Simon , Eric Blayo , Laurent Debreu
GODAE Final Symposium, Nov 2008, Nice, France
Conference papers inria-00344507v1

Assimilation de données variationnelle pour des modèles multi-grilles

Ehouarn Simon , Laurent Debreu , Eric Blayo
Colloque national sur l'assimilation de données, May 2006, Toulouse, France
Conference papers hal-00171710v1

4D-Variational data assimilation for locally nested numerical models

Ehouarn Simon , Laurent Debreu , Eric Blayo
European Geophysical Union General Assembly 2009, Apr 2009, Vienna, Austria
Conference papers hal-00795819v1

4D Variational Data Assimilation for Locally Nested Models : complementary theoretical aspects and application to a 2D shallow water model

Ehouarn Simon , Laurent Debreu , Eric Blayo
International Journal for Numerical Methods in Fluids, 2011, 66 (2), pp.135-161. ⟨10.1002/fld.2244⟩
Journal articles istex hal-00658105v1

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

Adrien Rouvière , Lucas Pascal , Fabien Méry , Ehouarn Simon , Serge Gratton et al.
AIAA SCITECH 2022 Forum, Jan 2022, San Diego, CA (virtual), United States. pp.AIAA 2022-1073, ⟨10.2514/6.2022-1073⟩
Conference papers hal-03510042v1

Guaranteeing the convergence of the saddle formulation for weakly constrained 4D‐Var data assimilation

Serge Gratton , Selime Gürol , Ehouarn Simon , Philippe Toint
Quarterly Journal of the Royal Meteorological Society, 2018, 144 (717), pp.2592-2602. ⟨10.1002/qj.3355⟩
Journal articles hal-02959392v1

Lp‐norm regularization approaches in variational data assimilation

Antoine Bernigaud , Serge Gratton , Flavia Lenti , Ehouarn Simon , Oumaima Sohab et al.
Quarterly Journal of the Royal Meteorological Society, 2021, 147, pp.2067 - 2081. ⟨10.1002/qj.4010⟩
Journal articles hal-03160275v1

A note on inexact inner products in GMRES

Serge Gratton , Ehouarn Simon , David Titley-Peloquin , Philippe Toint
SIAM Journal on Matrix Analysis and Applications, 2022, 43 (3)
Journal articles hal-03637231v1
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Experiences in multiyear combined state-parameter estimation with an ecosystem model of the North Atlantic and Arctic Oceans using the Ensemble Kalman Filter.

Ehouarn Simon , Annette Samuelsen , Laurent Bertino , Sandrine Mouysset
Journal of Marine Systems, 2015, 152, pp.1-17. ⟨10.1016/j.jmarsys.2015.07.004⟩
Journal articles hal-02960624v1

4D variational data assimilation for locally nested models

Ehouarn Simon , Laurent Debreu , Eric Blayo
European Geophysical Union General Assembly, Apr 2006, Vienne, Austria
Conference papers hal-00171657v1

A note on preconditioning weighted linear least-squares, with consequences for weakly constrained variational data assimilation

Serge Gratton , Selime Gürol , Ehouarn Simon , Philippe Toint
Quarterly Journal of the Royal Meteorological Society, 2018, 144 (712), pp.934-940. ⟨10.1002/qj.3262⟩
Journal articles hal-02959395v1

Multigrid algorithms and local mesh refinement methods in the context of variational data assimilation

Laurent Debreu , Emilie Neveu , François Xavier Le Dimet , Ehouarn Simon
Eric Blayo; Marc Bocquet; Emmanuel Cosme; F. Cugliandolo Leticia. Advanced Data Assimilation for Geosciences: Lecture Notes of the Les Houches School of Physics: Special Issue, June 2012, Oxford University Press, pp.576, 2014, Lecture notes of "Les Houches" summer school 2012, 9780198723844. ⟨10.1093/acprof:oso/9780198723844.003.0017⟩
Book sections hal-01095939v1
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An algorithm for the minimization of nonsmooth nonconvex functions using inexact evaluations and its worst-case complexity

Serge Gratton , Ehouarn Simon , Philippe Toint
Mathematical Programming, Series A, 2020, ⟨10.1007/s10107-020-01466-5⟩
Journal articles hal-02943960v1
Image document

Neural prediction model for transition onset of a boundary-layer in presence of 2D surface defects

Adrien Rouviere , Lucas Pascal , Fabien Méry , Ehouarn Simon , Serge Gratton et al.
56th 3AF International Conference on Applied Aerodynamics (AERO 2022), Association Aéronautique et Astronautique de France (3AF), Mar 2022, Toulouse, France. pp.1073, ⟨10.2514/6.2022-1073⟩
Conference papers hal-03909124v1