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Cloaking via anomalous localized resonance for doubly complementary media in the quasistatic regime

Hoai-Minh Nguyen (2015)

Journal of the European Mathematical Society

This paper is devoted to the study of cloaking via anomalous localized resonance (CALR) in the two- and three-dimensional quasistatic regimes. CALR associated with negative index materials was discovered by Milton and Nicorovici [21] for constant plasmonic structures in the two-dimensional quasistatic regime. Two key features of this phenomenon are the localized resonance, i.e., the fields blow up in some regions and remain bounded in some others, and the connection between the localized resonance...

Comportement à l'infini des solutions des équations de Navier-Stokes et propriété des ensembles fonctionnels invariants (ou attracteurs)

Colette Guillopé (1982)

Annales de l'institut Fourier

Les données, i.e. l’ouvert Ω et la force appliquée f , sont supposées de classe 𝒞 . Il est montré que toute solution des équations de Navier-Stokes dans l’ouvert Ω , bornée dans H 1 ( Ω ) N ( N = 2 ou 3 ) sur un intervalle de temps semi-infini ( t 0 + ) , est aussi bornée, pour t + , dans tous les espaces H m ( Ω ) N . Il en résulte que tout ensemble fonctionnel invariant ou attracteur borné dans H 1 ( Ω ) ( N (ou même H 1 / 2 + ϵ ( Ω ) N , ϵ > 0 ) est porté par 𝒞 ( Ω ) . Le cas où les forces appliquées dérivent d’un potentiel (i.e. f = 0 ) est abordé : il est montré que toute solution...

Controllable systems of partial differential equations

František Tumajer (1986)

Aplikace matematiky

In the paper definitions of various kinds of stability and boundedness of solutions of linear controllable systems of partial differential equations are introduced and their interconnections are derived. By means of Ljapunov's functions theorems are proved which give necessary and sufficient conditions for particular kinds of stability and boundedness of the solutions.

Convergence results for unbounded solutions of first order non-linear differential-functional equations

Henryk Leszczyński (1996)

Annales Polonici Mathematici

We consider the Cauchy problem in an unbounded region for equations of the type either D t z ( t , x ) = f ( t , x , z ( t , x ) , z ( t , x ) , D x z ( t , x ) ) or D t z ( t , x ) = f ( t , x , z ( t , x ) , z , D x z ( t , x ) ) . We prove convergence of their difference analogues by means of recurrence inequalities in some wide classes of unbounded functions.

Destabilization for quasivariational inequalities of reaction-diffusion type

Vítězslav Babický (2000)

Applications of Mathematics

We consider a reaction-diffusion system of the activator-inhibitor type with unilateral boundary conditions leading to a quasivariational inequality. We show that there exists a positive eigenvalue of the problem and we obtain an instability of the trivial solution also in some area of parameters where the trivial solution of the same system with Dirichlet and Neumann boundary conditions is stable. Theorems are proved using the method of a jump in the Leray-Schauder degree.

Diffusion and cross-diffusion in pattern formation

Wei-Ming Ni (2004)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

We discuss the stability and instability properties of steady state solutions to single equations, shadow systems, as well as 2 × 2 systems. Our basic observation is that the more complicated the pattern are, the more unstable they tend to be.

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