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On the long-time behaviour of solutions of the p-Laplacian parabolic system

Paweł Goldstein (2008)

Colloquium Mathematicae

Convergence of global solutions to stationary solutions for a class of degenerate parabolic systems related to the p-Laplacian operator is proved. A similar result is obtained for a variable exponent p. In the case of p constant, the convergence is proved to be ¹ l o c , and in the variable exponent case, L² and W 1 , p ( x ) -weak.

On the solution of inverse problems for generalized oxygen consumption

Denis Constales, Jozef Kačur (2001)

Applications of Mathematics

We present the solution of some inverse problems for one-dimensional free boundary problems of oxygen consumption type, with a semilinear convection-diffusion-reaction parabolic equation. Using a fixed domain transformation (Landau’s transformation) the direct problem is reduced to a system of ODEs. To minimize the objective functionals in the inverse problems, we approximate the data by a finite number of parameters with respect to which automatic differentiation is applied.

On the solution of the heat equation with nonlinear unbounded memory

Alexander Doktor (1985)

Aplikace matematiky

The paper deals with the question of global solution u , τ to boundary value problem for the system of semilinear heat equation for u and complementary nonlinear differential equation for τ (“thermal memory”). Uniqueness of the solution is shown and the method of successive approximations is used for the proof of existence of a global solution provided the condition ( 𝒫 ) holds. The condition ( 𝒫 ) is verified for some particular cases (e. g.: bounded nonlinearity, homogeneous Neumann problem (even for unbounded...

On the temperature distribution in cold ice

James N. Flavin, Salvatore Rionero (1997)

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

The linear heat equation predicts that the variations of temperature along a cold ice sheet {i.e. at a temperature less than is freezing point) due to a sudden increase in air temperature, are very very slow. Based on this we represent the nonlinear evolution of an ice sheet as a sequence of steady states. As a first fundamental indication that this model is correct well posedness with respect to the variations of initial and boundary data is proved. Further an estimate of the error made in evaluating...

On the viscous Allen-Cahn and Cahn-Hilliard systems with Willmore regularization

Ahmad Makki (2016)

Applications of Mathematics

We consider the viscous Allen-Cahn and Cahn-Hilliard models with an additional term called the nonlinear Willmore regularization. First, we are interested in the well-posedness of these two models. Furthermore, we prove that both models possess a global attractor. In addition, as far as the viscous Allen-Cahn equation is concerned, we construct a robust family of exponential attractors, i.e. attractors which are continuous with respect to the perturbation parameter. Finally, we give some numerical...

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