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Homogenization at different linear scales, bounded martingales and the two-scale shuffle limit

Kévin Santugini (2013)

ESAIM: Control, Optimisation and Calculus of Variations

In this paper, we consider two-scale limits obtained with increasing homogenization periods, each period being an entire multiple of the previous one. We establish that, up to a measure preserving rearrangement, these two-scale limits form a martingale which is bounded: the rearranged two-scale limits themselves converge both strongly in L2 and almost everywhere when the period tends to  +∞. This limit, called the Two-Scale Shuffle limit, contains all the information present in all the two-scale...

Homogenization in perforated domains with rapidly pulsing perforations

Doina Cioranescu, Andrey L. Piatnitski (2003)

ESAIM: Control, Optimisation and Calculus of Variations

The aim of this paper is to study a class of domains whose geometry strongly depends on time namely. More precisely, we consider parabolic equations in perforated domains with rapidly pulsing (in time) periodic perforations, with a homogeneous Neumann condition on the boundary of the holes. We study the asymptotic behavior of the solutions as the period ε of the holes goes to zero. Since standard conservation laws do not hold in this model, a first difficulty is to get a priori estimates of the...

Homogenization in perforated domains with rapidly pulsing perforations

Doina Cioranescu, Andrey L. Piatnitski (2010)

ESAIM: Control, Optimisation and Calculus of Variations

The aim of this paper is to study a class of domains whose geometry strongly depends on time namely. More precisely, we consider parabolic equations in perforated domains with rapidly pulsing (in time) periodic perforations, with a homogeneous Neumann condition on the boundary of the holes. We study the asymptotic behavior of the solutions as the period ε of the holes goes to zero. Since standard conservation laws do not hold in this model, a first difficulty is to get a priori estimates...

Homogenization of a boundary condition for the heat equation

Ján Filo, Stephan Luckhaus (2000)

Journal of the European Mathematical Society

An asymptotic analysis is given for the heat equation with mixed boundary conditions rapidly oscillating between Dirichlet and Neumann type. We try to present a general framework where deterministic homogenization methods can be applied to calculate the second term in the asymptotic expansion with respect to the small parameter characterizing the oscillations.

Homogenization of a capillary phenomena.

N. Labani, Mongi Mabrouk (1998)

Publicacions Matemàtiques

We study the height of a liquid in a tube when it contains a great number of thin vertical bars and when its border is finely strained. For this, one uses an epi-convergence method.

Homogenization of a carcinogenesis model with different scalings with the homogenization parameter

Isabell Graf, Malte A. Peter (2014)

Mathematica Bohemica

In the context of periodic homogenization based on two-scale convergence, we homogenize a linear system of four coupled reaction-diffusion equations, two of which are defined on a manifold. The system describes the most important subprocesses modeling the carcinogenesis of a human cell caused by Benzo-[a]-pyrene molecules. These molecules are activated to carcinogens in a series of chemical reactions at the surface of the endoplasmic reticulum, which constitutes a fine structure inside the cell....

Homogenization of a dual-permeability problem in two-component media with imperfect contact

Abdelhamid Ainouz (2015)

Applications of Mathematics

In this paper, we study the macroscopic modeling of a steady fluid flow in an ε -periodic medium consisting of two interacting systems: fissures and blocks, with permeabilities of different order of magnitude and with the presence of flow barrier formulation at the interfacial contact. The homogenization procedure is performed by means of the two-scale convergence technique and it is shown that the macroscopic model is a one-pressure field model in a one-phase flow homogenized medium.

Homogenization of a linear parabolic problem with a certain type of matching between the microscopic scales

Pernilla Johnsen, Tatiana Lobkova (2018)

Applications of Mathematics

This paper is devoted to the study of the linear parabolic problem ε t u ε ( x , t ) - · ( a ( x / ε , t / ε 3 ) u ε ( x , t ) ) = f ( x , t ) by means of periodic homogenization. Two interesting phenomena arise as a result of the appearance of the coefficient ε in front of the time derivative. First, we have an elliptic homogenized problem although the problem studied is parabolic. Secondly, we get a parabolic local problem even though the problem has a different relation between the spatial and temporal scales than those normally giving rise to parabolic local problems....

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 a Periodic Parabolic Cauchy Problem in the Sobolev Space H1 (ℝd)

T. Suslina (2010)

Mathematical Modelling of Natural Phenomena

In L2(ℝd; ℂn), we consider a wide class of matrix elliptic second order differential operators 𝒜 ε with rapidly oscillating coefficients (depending on x/ε). For a fixed τ > 0 and small ε > 0, we find approximation of the operator exponential exp(− 𝒜 ετ) in the (L2(ℝd; ℂn) → H1(ℝd; ℂn))-operator norm with an error term of order ε. In this approximation, the corrector is taken...

Homogenization of a semilinear parabolic PDE with locally periodic coefficients: a probabilistic approach

Abdellatif Benchérif-Madani, Étienne Pardoux (2007)

ESAIM: Probability and Statistics

In this paper, a singular semi-linear parabolic PDE with locally periodic coefficients is homogenized. We substantially weaken previous assumptions on the coefficients. In particular, we prove new ergodic theorems. We show that in such a weak setting on the coefficients, the proper statement of the homogenization property concerns viscosity solutions, though we need a bounded Lipschitz terminal condition.

Homogenization of a singular random one-dimensional PDE

Bogdan Iftimie, Étienne Pardoux, Andrey Piatnitski (2008)

Annales de l'I.H.P. Probabilités et statistiques

This paper deals with the homogenization problem for a one-dimensional parabolic PDE with random stationary mixing coefficients in the presence of a large zero order term. We show that under a proper choice of the scaling factor for the said zero order terms, the family of solutions of the studied problem converges in law, and describe the limit process. It should be noted that the limit dynamics remain random.

Homogenization of a spectral equation with drift in linear transport

Guillaume Bal (2001)

ESAIM: Control, Optimisation and Calculus of Variations

This paper deals with the homogenization of a spectral equation posed in a periodic domain in linear transport theory. The particle density at equilibrium is given by the unique normalized positive eigenvector of this spectral equation. The corresponding eigenvalue indicates the amount of particle creation necessary to reach this equilibrium. When the physical parameters satisfy some symmetry conditions, it is known that the eigenvectors of this equation can be approximated by the product of two...

Homogenization of a spectral equation with drift in linear transport

Guillaume Bal (2010)

ESAIM: Control, Optimisation and Calculus of Variations

This paper deals with the homogenization of a spectral equation posed in a periodic domain in linear transport theory. The particle density at equilibrium is given by the unique normalized positive eigenvector of this spectral equation. The corresponding eigenvalue indicates the amount of particle creation necessary to reach this equilibrium. When the physical parameters satisfy some symmetry conditions, it is known that the eigenvectors of this equation can be approximated by the product...

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