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Weighted Poincaré and Sobolev inequalites for vector fields satisfying Hörmander's condition and applications.

Guozhen Lu (1992)

Revista Matemática Iberoamericana

In this paper we mainly prove weighted Poincaré inequalities for vector fields satisfying Hörmander's condition. A crucial part here is that we are able to get a pointwise estimate for any function over any metric ball controlled by a fractional integral of certain maximal function. The Sobolev type inequalities are also derived. As applications of these weighted inequalities, we will show the local regularity of weak solutions for certain classes of strongly degenerate differential operators formed...

Well-posedness and regularity for a parabolic-hyperbolic Penrose-Fife phase field system

Elisabetta Rocca (2005)

Applications of Mathematics

This work is concerned with the study of an initial boundary value problem for a non-conserved phase field system arising from the Penrose-Fife approach to the kinetics of phase transitions. The system couples a nonlinear parabolic equation for the absolute temperature with a nonlinear hyperbolic equation for the phase variable χ , which is characterized by the presence of an inertial term multiplied by a small positive coefficient μ . This feature is the main consequence of supposing that the response...

Well-posedness for systems representing electromagnetic/acoustic wavefront interaction

H. T. Banks, J. K. Raye (2002)

ESAIM: Control, Optimisation and Calculus of Variations

In this paper we consider dispersive electromagnetic systems in dielectric materials in the presence of acoustic wavefronts. A theory for existence, uniqueness, and continuous dependence on data is presented for a general class of systems which include acoustic pressure-dependent Debye polarization models for dielectric materials.

Well-posedness for Systems Representing Electromagnetic/Acoustic Wavefront Interaction

H. T. Banks, J. K. Raye (2010)

ESAIM: Control, Optimisation and Calculus of Variations

In this paper we consider dispersive electromagnetic systems in dielectric materials in the presence of acoustic wavefronts. A theory for existence, uniqueness, and continuous dependence on data is presented for a general class of systems which include acoustic pressure-dependent Debye polarization models for dielectric materials.

Wellposedness for the system modelling the motion of a rigid body of arbitrary form in an incompressible viscous fluid

Patricio Cumsille, Takéo Takahashi (2008)

Czechoslovak Mathematical Journal

In this paper, we consider the interaction between a rigid body and an incompressible, homogeneous, viscous fluid. This fluid-solid system is assumed to fill the whole space d , d = 2 or 3 . The equations for the fluid are the classical Navier-Stokes equations whereas the motion of the rigid body is governed by the standard conservation laws of linear and angular momentum. The time variation of the fluid domain (due to the motion of the rigid body) is not known a priori, so we deal with a free boundary...

Which electric fields are realizable in conducting materials?

Marc Briane, Graeme W. Milton, Andrejs Treibergs (2014)

ESAIM: Mathematical Modelling and Numerical Analysis - Modélisation Mathématique et Analyse Numérique

In this paper we study the realizability of a given smooth periodic gradient field ∇u defined in Rd, in the sense of finding when one can obtain a matrix conductivity σ such that σ∇u is a divergence free current field. The construction is shown to be always possible locally in Rd provided that ∇u is non-vanishing. This condition is also necessary in dimension two but not in dimension three. In fact the realizability may fail for non-regular gradient fields, and in general the conductivity cannot...

Which sequences of holes are admissible for periodic homogenization with Neumann boundary condition?

Alain Damlamian, Patrizia Donato (2002)

ESAIM: Control, Optimisation and Calculus of Variations

In this paper we give a general presentation of the homogenization of Neumann type problems in periodically perforated domains, including the case where the shape of the reference hole varies with the size of the period (in the spirit of the construction of self-similar fractals). We shows that H 0 -convergence holds under the extra assumption that there exists a bounded sequence of extension operators for the reference holes. The general class of Jones-domains gives an example where this result applies....

Which sequences of holes are admissible for periodic homogenization with Neumann boundary condition?

Alain Damlamian, Patrizia Donato (2010)

ESAIM: Control, Optimisation and Calculus of Variations

In this paper we give a general presentation of the homogenization of Neumann type problems in periodically perforated domains, including the case where the shape of the reference hole varies with the size of the period (in the spirit of the construction of self-similar fractals). We shows that H0-convergence holds under the extra assumption that there exists a bounded sequence of extension operators for the reference holes. The general class of Jones-domains gives an example where this result...

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