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Homogenization of a monotone problem in a domain with oscillating boundary

Dominique Blanchard, Luciano Carbone, Antonio Gaudiello (2010)

ESAIM: Mathematical Modelling and Numerical Analysis

We study the asymptotic behaviour of the following nonlinear problem: { - div ( a ( D u h ) ) + | u h | p - 2 u h = f in Ω h , a ( D u h ) · ν = 0 on Ω h , . in a domain Ωh of n whose boundary ∂Ωh contains an oscillating part with respect to h when h tends to ∞. The oscillating boundary is defined by a set of cylinders with axis 0xn that are h-1-periodically distributed. We prove that the limit problem in the domain corresponding to the oscillating boundary identifies with a diffusion operator with respect to xn coupled with an algebraic problem for the limit fluxes.

Homogenization of constrained optimal control problems for one-dimensional elliptic equations on periodic graphs

Peter I. Kogut, Günter Leugering (2009)

ESAIM: Control, Optimisation and Calculus of Variations

We are concerned with the asymptotic analysis of optimal control problems for 1 -D partial differential equations defined on a periodic planar graph, as the period of the graph tends to zero. We focus on optimal control problems for elliptic equations with distributed and boundary controls. Using approaches of the theory of homogenization we show that the original problem on the periodic graph tends to a standard linear quadratic optimal control problem for a two-dimensional homogenized system, and...

Homogenization of constrained optimal control problems for one-dimensional elliptic equations on periodic graphs

Peter I. Kogut, Günter Leugering (2008)

ESAIM: Control, Optimisation and Calculus of Variations

We are concerned with the asymptotic analysis of optimal control problems for 1-D partial differential equations defined on a periodic planar graph, as the period of the graph tends to zero. We focus on optimal control problems for elliptic equations with distributed and boundary controls. Using approaches of the theory of homogenization we show that the original problem on the periodic graph tends to a standard linear quadratic optimal control problem for a two-dimensional homogenized system,...

Homogenization of highly oscillating boundaries and reduction of dimension for a monotone problem

Dominique Blanchard, Antonio Gaudiello (2010)

ESAIM: Control, Optimisation and Calculus of Variations

We investigate the asymptotic behaviour, as ε → 0, of a class of monotone nonlinear Neumann problems, with growth p-1 (p ∈]1, +∞[), on a bounded multidomain Ω ε N (N ≥ 2). The multidomain ΩE is composed of two domains. The first one is a plate which becomes asymptotically flat, with thickness hE in the xN direction, as ε → 0. The second one is a “forest" of cylinders distributed with ε-periodicity in the first N - 1 directions on the upper side of the plate. Each cylinder has a small...

Homogenization of quadratic complementary energies: a duality example

Hélia Serrano (2011)

Mathematica Bohemica

We study an example in two dimensions of a sequence of quadratic functionals whose limit energy density, in the sense of Γ -convergence, may be characterized as the dual function of the limit energy density of the sequence of their dual functionals. In this special case, Γ -convergence is indeed stable under the dual operator. If we perturb such quadratic functionals with linear terms this statement is no longer true.

Homogenization of some nonlinear problems with specific dependence upon coordinates

P. Courilleau, S. Fabre, J. Mossino (2001)

Bollettino dell'Unione Matematica Italiana

Questo articolo considera una successione di equazioni differenziali a derivate parziali non lineari in forma di divergenza del tipo - div Q ϵ G x , N ϵ u = f ϵ , in un dominio limitato Ω dello spazio n -dimensionale; Q ϵ = Q ϵ x e N ϵ = N ϵ x sono matrici con coefficenti limitati, N ϵ e è invertibile e la sua matrice inversa R ϵ ha anche coefficenti limitati. La non linearità è dovuta alla funzione G = G x , ξ ; la condizione di crescita, la monotonicità e le ipotesi di coercitività sono modellate sul p -Laplaciano, 1 < p < , ed assicurano l'esistenza di una soluzione...

Homogenization with uncertain input parameters

Luděk Nechvátal (2010)

Mathematica Bohemica

We homogenize a class of nonlinear differential equations set in highly heterogeneous media. Contrary to the usual approach, the coefficients in the equation characterizing the material properties are supposed to be uncertain functions from a given set of admissible data. The problem with uncertainties is treated by means of the worst scenario method, when we look for a solution which is critical in some sense.

Currently displaying 81 – 100 of 112