Publicaciones

• ART

Optimization of explicit RKN schemes to minimize spurious reflections from shock wave propagation on non-uniform grids

Emmanuel Creusé, Mamadou N'Diaye, Juliette Venel, Cédric Hubert, Nicolas Leconte

The propagation of shock waves on non-uniform grids appears, for example, in some impact problems of the fast dynamics type, where a finer mesh can typically be employed in regions of interest, leading to mesh ratios that can range from 10 to 20 or even more. Unfortunately, unwanted spurious...

International Journal for Numerical Methods in Engineering, 2026. ⟨hal-05144415v2⟩

• ART

Block-Additive Gaussian Processes under Monotonicity Constraints

Mathis Deronzier, Andrés F. López-Lopera, François Bachoc, Olivier Roustant, Jérémy Rohmer

We generalize the additive constrained Gaussian process framework to handle interactions between input variables while enforcing monotonicity constraints everywhere on the input space. The block-additive structure of the model is particularly suitable in the presence of interactions, while...

Statistics and Computing, 2026, 36 (1), pp.42. ⟨10.1007/s11222-025-10791-8⟩. ⟨hal-05441153⟩

• UNDEFINED

MULTIPLE SOLUTIONS AND SIMULATIONS FOR AN ION FLOW FIELD PROBLEM APPLIED TO HVDC TRANSMISSION LINES

Madeline Chauvier, Serge Nicaise, Christophe Troestler, Juliette Venel

This paper initiates a mathematical investigation of a PDE model for the transport of high voltage direct current via overhead lines. We prove the existence of infinitely many solutions, give necessary conditions for existence, explicitly compute the continuum of all radial solutions, and develop a...

2025. ⟨hal-05357732⟩

• ART

Carleman-Based Reconstruction Algorithm on a wave Network

Lucie Baudouin, Maya de Buhan, Emmanuelle Crépeau, Julie Valein

In the context of a network of vibrating strings, modelled by interconnected linear partial differential equations, we are interested in the reconstruction of a zeroth order term of each one-dimensional wave equation involved, using some appropriate external boundary measurements. More precisely,...

Mathematics of Control, Signals, and Systems, 2025, 37, pp.621-660. ⟨10.1007/s00498-025-00413-z⟩. ⟨hal-04361363⟩

• ART

Determination of discontinuous diffusion coefficients for the heat equation on a tree-shaped network

Emmanuelle Crépeau, Lionel Rosier, Julie Valein

In this paper, we study the heat equation on a tree-shaped network with a piecewise regular diffusion coefficient. By developing new Carleman estimates, we establish stability results for the identification of the diffusion coefficient. These stability estimates are derived using either internal...

Inverse Problems, 2025, 41 (7), pp.075001. ⟨10.1088/1361-6420/ade3f9⟩. ⟨hal-05464931⟩

• UNDEFINED

Error Bounds for a Kernel-Based Constrained Optimal Smoothing Approximation

Laurence Grammont, François Bachoc, Andrés F. López-Lopera

This paper establishes error bounds for the convergence of a piecewise linear approximation of the constrained optimal smoothing problem posed in a reproducing kernel Hilbert space (RKHS). This problem can be reformulated as a Bayesian estimation problem involving a Gaussian process related to the...

2025. ⟨hal-04645086v2⟩

• ART

Thermoelastic properties of polycrystalline strontium titanium silicate Sr₂TiSi₂O₈ synthesized via the reactive sintering method

Oussama Zwein, Maurice Gonon, Sandra Abdelouhab, Isabella Mastroianni, Marc Duquennoy

The aim of the work presented in this paper is to investigate the thermoelastic properties of polycrystalline Sr-fresnoite Sr2TiSi2O8 (STS). On that purpose, Sr2TiSi2O8 samples were synthesized by solid state reactive sintering from SrCO3, TiO2 and SiO2 powders. The thermal expansion behaviour of...

Journal of the European Ceramic Society, 2025, 45 (6), pp.117224. ⟨10.1016/j.jeurceramsoc.2025.117224⟩. ⟨hal-04923467⟩

• ART

Effects of La2O3 on structure and mechanical properties of sodium borosilicate glass

Meriem Ben Zennou, Ahmed Bachar, Meriem Chrifi Alaoui, Frédéric Jenot, Rachid Amrousse, Aurélien Canizares, Yann Vaills, Stuart Hampshire, Mohamed Rguiti, Assia Mabrouk

To develop rare-earth-doped borosilicate glasses with enhanced mechanical properties, lanthanum sodium borosilicate glasses were successfully synthesized using a fusion method. The glass composition was (mol.%): 55SiO2 - 25B2O3 – (20-x)Na2O - xLa2O3 (x = 1, 2, 3, 4, and 5). The primary aim was to...

Ceramics International, 2025, ⟨10.1016/j.ceramint.2025.05.337⟩. ⟨hal-05148570⟩

• ART

Numerical Simulation and Experimental Verification of Mechanical Displacements in Piezoelectric Transformer

Faiza Boukazouha, Guylaine Poulin-Vittrant, Mohamed Rguiti, Marc Lethiecq

Abstract Since its invention, piezoelectric transformers (PTs) have been extensively studied and its performances have been continuously improved. Nowadays, such devices are designed in sophisticated architectures with associated models describing their behavior quite accurately. However, the...

Advanced Theory and Simulations, 2025, 8 (8), pp.2401232. ⟨10.1002/adts.202401232⟩. ⟨hal-05285962⟩

• POSTER

Influence de la quantité de verre résiduel et la microstructure des vitrocéramiques polaires piézoélectriques sur la propagation des ondes acoustiques de surface (SAW)

Oussama Zwein, Marc Duquennoy, Dame Fall, Maurice Gonon, Zakariae Oumekloul, Christian Courtois

GFC 18, Mar 2025, Orléans, France. ⟨hal-05063490⟩