Publications

• Article dans une revue

Polynomial decay rate for a wave equation with general acoustic boundary feedback laws

Serge Nicaise, Zainab Abbas

We consider the stabilization of the wave equation by a general class of acoustic boundary feedback laws at one extremity. This system is not uniformly stable but we furnish sufficient conditions that guarantee a polynomial stability. Our method combines the use of an observability inequality for…

SeMA Journal: Boletin de la Sociedad Española de Matemática Aplicada, 2013, 61 (1), pp.19-48. ⟨10.1007/s40324-013-0002-5⟩. ⟨hal-03134810⟩

• Communication dans un congrès

Courbes algébriques-trigonométriques à holographe pythagorien et leur utilisation pour résoudre le problème d'interpolation de Hermite

Laura Saini, Lucia Romani, Gudrun Albrecht

Journées de modélisation géométrique, 2013, Marseille, France. ⟨hal-03187567⟩

• Article dans une revue

Mechanical Properties of Porosity-Free Beta Tricalcium Phosphate (<i>β</i>-TCP) Ceramic by Sharp and Spherical Indentations

Didier Chicot, Arnaud Tricoteaux, J. Lesage, Anne Leriche, Michel Descamps, E. Rguiti-Constantin

Instrumented indentation has been developed for determining the mechanical properties of materials but an accurate determination of these properties requires attention on contact stiffness analysis, indentation size effect, elastic modulus mode of calculation, role of stress distribution around the…

New Journal of Glass and Ceramics, 2013, 03 (01), pp.16-28. ⟨10.4236/njgc.2013.31004⟩. ⟨hal-03586273⟩

• Article dans une revue

On the asymptotic behavior of transmission thin shell problems

Ismail Merabet, Serge Nicaise, D.A. Chacha

In this paper we study the asymptotic behavior of two-dimensional transmission problems for the linear Koiter model of an elastic multi-structure composed of two thin shells with the same thickness ε<<1. Contrary to the case of membrane shells, the formal limit problem, i.e., for ε=0, fails…

Asymptotic Analysis, 2013, 82 (1-2), p. 163-185. ⟨10.3233/ASY-121144⟩. ⟨hal-03163628⟩

• Article dans une revue

Realizable Galois module classes over the group ring for non abelian extensions, Classes galoisiennes réalisables sur l’anneau de groupe d’extensions non abéliennes

Nigel Byott, Bouchaïb Sodaïgui

Given an algebraic number field k and a finite group T, we write R(Ok[T]) for the subset of the locally free classgroup Cl(Ok[T]) consisting of the classes of rings of integers ON in tame Galois extensions N/k with Gal(N/k) T = T. We determine R(Ok[T]), and show it is a subgroup of Cl(Ok[T]) by…

Annales de l'Institut Fourier, 2013, 63 (1), p. 303-371. ⟨10.5802/aif.2762⟩. ⟨hal-03165412⟩

• Article dans une revue

Stabilization by switching time–delay

Kaïs Ammari, Serge Nicaise, Cristina Pignotti

In this paper we consider some stabilization problems for the wave equation with switching time-delay. We prove exponential stability results for appropriate damping coefficients. The proof of the main results is based on D'Alembert formula, observability inequality and some energy estimates.…

Asymptotic Analysis, 2013, 83 (3), pp.263-283. ⟨10.3233/ASY-131163⟩. ⟨hal-03138782⟩

• Article dans une revue

Uniformly exponentially or polynomially stable approximations for second order evolution equations and some applications

Farah Abdallah, Serge Nicaise, Julie Valein, Ali Wehbe

In this paper, we consider the approximation of second order evolution equations. It is well known that the approximated system by finite element or finite difference is not uniformly exponentially or polynomially stable with respect to the discretization parameter, even if the continuous system…

ESAIM: Control, Optimisation and Calculus of Variations, 2013, 19 (3), pp.844-887. ⟨10.1051/cocv/2012036⟩. ⟨hal-00755744⟩

• Article dans une revue

Lower and upper solutions for the heat equation on a polygonal domain of R2

Colette De Coster, Serge Nicaise

We consider the nonlinear periodic-Dirichlet heat equation on a polygonal domain of the plane in weighted Lp-Sobolev spaces equation presented Here f is Lp(0; T;Lpμ(Ω)-Caratheodory, where L pμ(Ω) = {v ε Lploc(Ω) : rμv ε Lp(Ω)}, with a real parameter μ and r(x) the distance from x to the set of…

Differential and integral equations, 2013, 26 (5/6), pp.603-622. ⟨hal-03137717⟩

• Article dans une revue

Spectral analysis and exponential or polynomial stability of some indefinite sign damped problems

F. Abdallah, D. Mercier, Serge Nicaise

In this paper, we consider two damped wave problems for which the damping terms are allowed to change their sign. Using a careful spectral analysis, we find critical values of the damping coefficients for which the problem becomes exponentially or polynomially stable up to these critical values.

Evolution Equations and Control Theory, 2013, 2, pp.1-33. ⟨10.3934/eect.2013.2.1⟩. ⟨hal-03134858⟩

• Article dans une revue

Photocatalytic solution discoloration and self-cleaning by polyester fabric functionalized with ZnO nanorods

Munir Ashraf, Philippe Champagne, Anne Perwuelz, Campagne Christine, Anne Leriche

Polyester fabric was functionalized with ZnO nanorods grown by hydrothermal method. The ZnO seeds were deposited on fabric which provided the sites for growth of nanorods. The functionalized fabric showed self-cleaning by degrading color stains and solution discoloration under the effect of…

Journal of Industrial Textiles, 2013, 44 (6), pp.884-898. ⟨10.1177/1528083713519662⟩. ⟨hal-03121037⟩