Publications

• Article dans une revue

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 de conférence

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⟩

• Pré-publication, Document de travail

Estimating weak Markov-switching AR(1) models

Yacouba Boubacar Mainassara, Armel Bra, Landy Rabehasaina

In this paper, we present the asymptotic properties of the moment estimator for autoregressive (AR for short) models subject to Markovian changes in regime under the assumption that the errors are uncorrelated but not necessarily independent. We relax the standard independence assumption on the…

2025. ⟨hal-04975822⟩

• Pré-publication, Document de travail

Estimation of subcritical Galton Watson processes with correlated immigration

Yacouba Boubacar Mainassara, Landy Rabehasaina

We consider an observed subcritical Galton Watson process $\{Y_n,\ n\in \mathbb{Z} \}$ with correlated stationary immigration process $\{\epsilon_n,\ n\in \mathbb{Z} \}$. Two situations are presented. The first one is when $\mbox{Cov}(\epsilon_0,\epsilon_k)=0$ for $k$ larger than some $k_0$: a…, Nous considérons un processus observé de Galton Watson $\{Y_n,\ n\in \mathbb{Z} \}$ avec immigration modélisé par un processus corrélé $\{\epsilon_n,\ n\in \mathbb{Z} \}$. Nous présentons des résultats d’estimation du taux de reproduction et l’espérance de l’immigration dans deux situations. La…

2025. ⟨hal-04549758v2⟩

• Pré-publication, Document de travail

Gaussian Process-driven Hidden Markov Models for Early Diagnosis of Infant Gait Anomalies

Luis Torres-Torres F., Jonatan Arias-García, Hernán F. García, Andrés F. López-Lopera, Jesús F. Vargas-Bonilla

Gait analysis is critical in the early detection and intervention of motor neurological disorders in infants. Despite its importance, traditional methods often struggle to model the high variability and rapid developmental changes inherent to infant gait. To address these challenges, we propose a…

2025. ⟨hal-04937628⟩

• Pré-publication, Document de travail

Null controllability of a highly coupled fourth-order parabolic system with one internal control

Nicolás Carreño, Eduardo Cerpa, Emmanuelle Crépeau, Claudia Moreno

<div><p>Controlling systems of partial differential equations with fewer controls than states has been a central topic in the last decades. The nature of the equations and existing couplings are key factors to consider. Even if we can find several works for parabolic systems, there are…

2025. ⟨hal-04934479⟩

• Pré-publication, Document de travail

Stability of discontinuous diffusion coefficients for the heat equation on a star-shaped tree

Emmanuelle Crépeau, Lionel Rosier, Julie Valein

In this paper, we study the heat equation on a star-shaped tree 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…

2025. ⟨hal-04931176⟩

• Communication dans un congrès

Limit theorems: some recent results

Laetitia Colombani, Olivier Durieu, Davide Giraudo, Vytauté Pilipauskaité, Lucas Reding

The article presents a series of recent results in the field of limit theorems which allow to appreciate the richness of this theme. These results include: the study of the asymptotic behaviour of cumulative processes with applications to Hawkes processes; maximal inequalities and functional…, Cet article présente une série de résultats récents sur le thème des théorèmes limites qui permettent d’apprécier la richesse de la thématique. Les résultats présentés regroupent : l’étude du comportement asymptotique des processus cumulatifs avec des applications aux processus de Hawkes; des…

Journées MAS 2022, Pierre Calka; Clément Marteau, Aug 2022, Rouen, France. pp.26-50, ⟨10.1051/proc/202580026⟩. ⟨hal-05005587⟩

• Pré-publication, Document de travail

Degenerate/singular beam-type equations: a controllability result

Akil Mohammad, Fragnelli Genni, Sbai Amine

The paper deals with the controllability of a degenerate/singular beam-type equation in divergence or in non-divergence form. In particular, we assume that the degeneracy and the singularity are at the same boundary point and we consider a suitable control $f$ localized on the non degenerate…

2025. ⟨hal-04901715⟩

• Article dans une revue

How Null Vector Performs in a Rational Bézier Curve with Mass Points

Lionel Garnier, Jean-Paul Bécar, Laurent Fuchs

This article points out the kinematics in tracing a Bézier curve defined by control mass points. A mass point is a point with a non-positive weight, a non-negative weight or a vector with a null weight. For any Bézier curve, the speeds at endpoints can be modified at the same time for both…

geometry, 2025, 2 (1), pp.1-35. ⟨10.3390/geometry2010001⟩. ⟨hal-04901396⟩