Publications

• Article dans une revue

Minimal contact CR submanifolds in S2 n+1 satisfying the δ(2)-Chen equality

Marian Ioan Munteanu, Luc Vrancken

In his book on Pseudo-Riemannian geometry, δ-invariants and applications, B.Y. Chen introduced a sequence of curvature invariants. Each of these invariants is used to obtain a lower bound for the length of the mean curvature vector for an immersion in a real space form. A submanifold is called an…

Journal of Geometry and Physics, 2014, 75, pp.92-97. ⟨10.1016/j.geomphys.2013.09.003⟩. ⟨hal-03184628⟩

• Article dans une revue

Stabilization of second-order evolution equations with time delay

Serge Nicaise, Cristina Pignotti

We consider second-order evolution equations in an abstract setting with damping and time delay and give sufficient conditions ensuring exponential stability. Our abstract framework is then applied to the wave equation, the elasticity system and the Petrovsky system.

Mathematics of Control, Signals, and Systems, 2014, 26 (4), pp.563-588. ⟨10.1007/s00498-014-0130-1⟩. ⟨hal-03159120⟩

• Article dans une revue

Polynomial stabilization of some dissipative hyperbolic systems

Kaïs Ammari, E. Feireisl, Serge Nicaise

We study the problem of stabilization for the acoustic system with a spatially distributed damping. Imposing various hypotheses on the structural properties of the damping term, we identify either exponential or polynomial decay of solutions with growing time. Exponential decay rate is shown by…

Discrete and Continuous Dynamical Systems - Series A, 2014, 34 (11), pp.4371-4388. ⟨10.3934/dcds.2014.34.4371⟩. ⟨hal-03138443⟩

• Article dans une revue

Exponential stability of abstract evolution equations with time delay

Serge Nicaise, Cristina Pignotti

We consider abstract semilinear evolution equations with a time-delay feedback. We show that, if the C (0)-semigroup describing the linear part of the model is exponentially stable, then the whole system retains this good property when a suitable smallness condition on the time-delay feedback is…

Journal of Evolution Equations, 2014, 15 (1), pp.107-129. ⟨10.1007/s00028-014-0251-5⟩. ⟨hal-03166075⟩

• Chapitre d'ouvrage

Introduction à la théorie des sous- et sur-solutions

Colette De Coster, Jalel Tabka

“Introduction à quelques problèmes d’EDP : notes du groupe de travail de l’équipe EDP du Laboratoire de Mathématiques et leurs Applications de Valenciennes, Ed. Universitaires Européennes, pp.1-41, 2014, 9786131506833. ⟨hal-03142454⟩

• Thèse

Développement et caractérisations de fibres piézoélectriques à âme métallique pour applications aéronautiques, Development and characterization of metal core piezoelectric fibres for aeronautic applications

Aurélien Dolay

Pour les applications aéronautiques, les fibres en céramique piézoélectrique à âme métallique permettent d'imaginer des solutions pour avoir des dispositifs actifs et des capteurs complétement intégrés dans des structures, telles que les composites renforcés par des fibres.La démarche de cette…, Metal core piezoelectric fibres are suitable for active devices and sensors fully embedded in structuresas fibres reinforced polymers for aeronautic applications.The aim of this study is to develop and characterize such fibres that have many advantages: radial mode activation allows the use of low…

Mécanique des matériaux [physics.class-ph]. Université de Valenciennes et du Hainaut-Cambresis, 2013. Français. ⟨NNT : 2013VALE0044⟩. ⟨tel-00991950⟩

• Rapport

Existence results for the $A-\varphi$ magnetodynamic formulation of the Maxwell system

Serge Nicaise

The $A/\varphi$ magnetodynamic Maxwell system given in its potential and space/time formulation is a popular model considered in the engineering community. We establish exitence of strong solutions with the help of the theory of Showalter on degenerated parabolic problems; using energy estimates,…

2013. ⟨hal-00917597⟩

• Article dans une revue

Sintering behavior and non-linear properties of ZnO varistors processed in microwave electric and magnetic fields at 2.45GHz

Alexandre Badev, Sylvain Marinel, Romain Heuguet, Etienne Savary, Dinesh Agrawal

A study of the densification behavior and grain growth mechanisms of ZnO-based varistors composed of 98 mol.% ZnO–2 mol.% (Bi2O3, Sb2O3, Co3O4, MnO2) has been carried out. The pressed samples were sintered in microwave electric (E) and magnetic (H) fields using a single-mode cavity of 2.45 GHz. The…

Acta Materialia, 2013, 61 (20), pp.7849-7858. ⟨10.1016/j.actamat.2013.09.023⟩. ⟨hal-02450338⟩

• Communication dans un congrès

On a new type of Pythagorean-Hodograph curves and their use in applications

Gudrun Albrecht

International Conference on Applied Mathematics and Informatics - ICAMI 2013, Nov 2013, San Andres Island, Colombia. ⟨hal-03156002⟩

• Article dans une revue

Elaboration and characterization of a low frequency and wideband piezoceramic generator for energy harvesting

Mohamed Rguiti, A. Hajjaji, Sophie d'Astorg, Christian Courtois, Anne Leriche

The aim of this work was to efficiently convert the mechanical vibrations into electrical energy by using direct piezoelectric effect. Most mechanical vibrations occur at low frequencies varying from 50 to 120 Hz. As piezoelectric converters provide maximum energy conversion when their natural…

Optical Materials, 2013, 36 (1), pp.8-12. ⟨10.1016/j.optmat.2013.07.017⟩. ⟨hal-03033179⟩