Displaying 101 – 120 of 268

Showing per page

Nonhomogeneous boundary conditions and curved triangular finite elements

Alexander Ženíšek (1981)

Aplikace matematiky

Approximation of nonhomogeneous boundary conditions of Dirichlet and Neumann types is suggested in solving boundary value problems of elliptic equations by the finite element method. Curved triangular elements are considered. In the first part of the paper the convergence of the finite element method is analyzed in the case of nonhomogeneous Dirichlet problem for elliptic equations of order 2 m + 2 , in the second part of the paper in the case of nonhomogeneous mixed boundary value problem for second order...

Numerical analysis of the general biharmonic problem by the finite element method

Jiří Hřebíček (1982)

Aplikace matematiky

The present paper deals with solving the general biharmonic problem by the finite element method using curved triangular finit C 1 -elements introduced by Ženíšek. The effect of numerical integration is analysed in the case of mixed boundary conditions and sufficient conditions for the uniform V O h -ellipticity are found.

On a Class of Elliptic Equations for the N-Laplacian in R^n with One-Sided Exponential Growth

Candela, Anna Maria, Squassina, Marco (2003)

Serdica Mathematical Journal

2000 Mathematics Subject Classification: 35J40, 49J52, 49J40, 46E30By means of a suitable nonsmooth critical point theory for lower semicontinuous functionals we prove the existence of infinitely many solutions for a class of quasilinear Dirichlet problems with symmetric non-linearities having a one-sided growth condition of exponential type.The research of the authors was partially supported by the MIUR project “Variational and topological methods in the study of nonlinear phenomena” (COFIN 2001)....

On a Liouville type theorem for isotropic homogeneous fully nonlinear elliptic equations in dimension two

Jean Dolbeault, Régis Monneau (2003)

Annali della Scuola Normale Superiore di Pisa - Classe di Scienze

In this paper we establish a Liouville type theorem for fully nonlinear elliptic equations related to a conjecture of De Giorgi in 2 . We prove that if the level lines of a solution have bounded curvature, then these level lines are straight lines. As a consequence, the solution is one-dimensional. The method also provides a result on free boundary problems of Serrin type.

On exact results in the finite element method

Ivan Hlaváček, Michal Křížek (2001)

Applications of Mathematics

We prove that the finite element method for one-dimensional problems yields no discretization error at nodal points provided the shape functions are appropriately chosen. Then we consider a biharmonic problem with mixed boundary conditions and the weak solution u . We show that the Galerkin approximation of u based on the so-called biharmonic finite elements is independent of the values of u in the interior of any subelement.

On Korn's second inequality

J. A. Nitsche (1981)

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

On monotone-like mappings in Orlicz-Sobolev spaces

Vesa Mustonen, Matti Tienari (1999)

Mathematica Bohemica

We study the mappings of monotone type in Orlicz-Sobolev spaces. We introduce a new class ( S m ) as a generalization of ( S + ) and extend the definition of quasimonotone map. We also prove existence results for equations involving monotone-like mappings.

On singular perturbation problems with Robin boundary condition

Henri Berestycki, Juncheng Wei (2003)

Annali della Scuola Normale Superiore di Pisa - Classe di Scienze

We consider the following singularly perturbed elliptic problem ϵ 2 Δ u - u + f ( u ) = 0 , u > 0 in Ω , ϵ u ν + λ u = 0 on Ω , where f satisfies some growth conditions, 0 λ + , and Ω N ( N > 1 ) is a smooth and bounded domain. The cases λ = 0 (Neumann problem) and λ = + (Dirichlet problem) have been studied by many authors in recent years. We show that, there exists a generic constant λ * > 1 such that, as ϵ 0 , the least energy solution has a spike near the boundary if λ λ * , and has an interior spike near the innermost part of the domain if λ > λ * . Central to our study is the corresponding problem...

Currently displaying 101 – 120 of 268