arXiv subjects

Ciprian G. Gal

Publications and source records attributed to Ciprian G. Gal.

21 records · Page 2Linked to original sources

arXiv2012

On a class of degenerate parabolic equations with dynamic boundary conditions

We consider a quasi-linear parabolic equation with nonlinear dynamic boundary conditions occurring as a natural generalization of the semilinear reaction-diffusion equation with dynamic boundary conditions. The corresponding class of initial and boundary value problems has already been studied previously, proving well-posedness and the existence of the global attractor. The goal of this note is to show that the previous analysis can be redone for more general nonlinearities by proving an additional (uniform) L\infty-estimate on the solutions. In particular, we derive new conditions which reflect an exact balance between the two nonlinear mechanisms involved, even when both the nonlinear (source) terms contribute in opposite directions.

math.DS↗

arXiv2011

Sharp estimates for the global attractor of scalar reaction-diffusion equations with a Wentzell boundary condition

In this paper, we derive optimal upper and lower bounds on the dimension of the attractor AW for scalar reaction-diffusion equations with a Wentzell (dynamic) boundary condition. We are also interested in obtaining explicit bounds about the constants involved in our asymptotic estimates, and to compare these bounds to previously known estimates for the dimension of the global attractor AK; K \in {D;N; P}, of reactiondiffusion equations subject to Dirichlet, Neumann and periodic boundary conditions. The explicit estimates we obtain show that the dimension of the global attractor AW is of different order than the dimension of AK; for each K \in {D;N; P} ; in all space dimensions that are greater or equal than three.

math.DS↗

arXiv2011

Nonlinear elliptic boundary value problems at resonance with nonlinear Wentzell boundary conditions

In the first part of the article, we give necessary and sufficient conditions for the solvability of a class of nonlinear elliptic boundary value problems with nonlinear boundary conditions involving the q-Laplace-Beltrami operator. In the second part, we give some additional results on existence, uniqueness and continuous dependence estimates of the weak solutions for these classes of nonlinear problems. Finally, we show that these solutions are also bounded and provide explicit estimates.

math.DS↗