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Reaction-diffusion systems: Destabilizing effect of conditions given by inclusions

Jan Eisner (2000)

Mathematica Bohemica

Sufficient conditions for destabilizing effects of certain unilateral boundary conditions and for the existence of bifurcation points for spatial patterns to reaction-diffusion systems of the activator-inhibitor type are proved. The conditions are related with the mollification method employed to overcome difficulties connected with empty interiors of appropriate convex cones.

Relaxation of optimal control problems in Lp-SPACES

Nadir Arada (2010)

ESAIM: Control, Optimisation and Calculus of Variations

We consider control problems governed by semilinear parabolic equations with pointwise state constraints and controls in an Lp-space (p < ∞). We construct a correct relaxed problem, prove some relaxation results, and derive necessary optimality conditions.

Relaxation of optimal control problems in 𝖫 𝗉 -spaces

Nadir Arada (2001)

ESAIM: Control, Optimisation and Calculus of Variations

We consider control problems governed by semilinear parabolic equations with pointwise state constraints and controls in an L p -space ( p &lt; ). We construct a correct relaxed problem, prove some relaxation results, and derive necessary optimality conditions.

Speed-up of reaction-diffusion fronts by a line of fast diffusion

Henri Berestycki, Anne-Charline Coulon, Jean-Michel Roquejoffre, Luca Rossi (2013/2014)

Séminaire Laurent Schwartz — EDP et applications

In these notes, we discuss a new model, proposed by H. Berestycki, J.-M. Roquejoffre and L. Rossi, to describe biological invasions in the plane when a strong diffusion takes place on a line. This model seems relevant to account for the effects of roads on the spreading of invasive species. In what follows, the diffusion on the line will either be modelled by the Laplacian operator, or the fractional Laplacian of order less than 1. Of interest to us is the asymptotic speed of spreading in the direction...

Stability for approximation methods of the one-dimensional Kobayashi-Warren-Carter system

Hiroshi Watanabe, Ken Shirakawa (2014)

Mathematica Bohemica

A one-dimensional version of a gradient system, known as “Kobayashi-Warren-Carter system”, is considered. In view of the difficulty of the uniqueness, we here set our goal to ensure a “stability” which comes out in the approximation approaches to the solutions. Based on this, the Main Theorem concludes that there is an admissible range of approximation differences, and in the scope of this range, any approximation method leads to a uniform type of solutions having a certain common features. Further,...

Strong unique continuation for the Lamé system with Lipschitz coefficients in three dimensions

Hang Yu (2011)

ESAIM: Control, Optimisation and Calculus of Variations

This paper studies the strong unique continuation property for the Lamé system of elasticity with variable Lamé coefficients λ, µin three dimensions, div ( μ ( u + u t ) ) + ( λ div u ) + V u = 0 whereλ and μ are Lipschitz continuous and V∈L∞. The method is based on the Carleman estimate with polynomial weights for the Lamé operator.

Strong unique continuation for the Lamé system with Lipschitz coefficients in three dimensions*

Hang Yu (2011)

ESAIM: Control, Optimisation and Calculus of Variations

This paper studies the strong unique continuation property for the Lamé system of elasticity with variable Lamé coefficients λ, µ in three dimensions, div ( μ ( u + u t ) ) + ( λ div u ) + V u = 0 where λ and μ are Lipschitz continuous and V∈L∞. The method is based on the Carleman estimate with polynomial weights for the Lamé operator.

The dynamics of weakly interacting fronts in an adsorbate-induced phase transition model

Shin-Ichiro Ei, Tohru Tsujikawa (2009)

Kybernetika

Hildebrand et al. (1999) proposed an adsorbate-induced phase transition model. For this model, Takei et al. (2005) found several stationary and evolutionary patterns by numerical simulations. Due to bistability of the system, there appears a phase separation phenomenon and an interface separating these phases. In this paper, we introduce the equation describing the motion of two interfaces in 2 and discuss an application. Moreover, we prove the existence of the traveling front solution which approximates...

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Т.Г. Плетнева, С.Д. Эйдельман (1973)

Matematiceskie issledovanija

Currently displaying 41 – 60 of 73