The search session has expired. Please query the service again.
The search session has expired. Please query the service again.
The search session has expired. Please query the service again.
The search session has expired. Please query the service again.
Displaying 1101 –
1120 of
1415
We are concerned with a finite element approximation for time-harmonic wave
propagation governed by the Helmholtz equation. The usually oscillatory behavior of
solutions, along with numerical dispersion, render standard finite element methods
grossly inefficient already in medium-frequency regimes. As an alternative, methods
that incorporate information about the solution in the form of plane waves have
been proposed. We focus on a class of Trefftz-type discontinuous Galerkin methods that
...
The method of reliable solutions alias the worst scenario method is applied to the problem of von Kármán equations with uncertain initial deflection. Assuming two-mode initial and total deflections and using Galerkin approximations, the analysis leads to a system of two nonlinear algebraic equations with one or two uncertain parameters-amplitudes of initial deflections. Numerical examples involve (i) minimization of lower buckling loads and (ii) maximization of the maximal mean reduced stress.
In this paper we propose a method for improving the convergence rate of the mixed finite element approximations for the Stokes eigenvalue problem. It is based on a postprocessing strategy that consists of solving an additional Stokes source problem on an augmented mixed finite element space which can be constructed either by refining the mesh or by using the same mesh but increasing the order of the mixed finite element space.
In this paper, we study a postprocessing procedure for improving
accuracy of the finite volume element approximations of semilinear
parabolic problems. The procedure amounts to solve a source problem
on a coarser grid and then solve a linear elliptic problem on a
finer grid after the time evolution is finished. We derive error
estimates in the L2 and H1 norms for the standard finite
volume element scheme and an improved error estimate in the H1
norm. Numerical results demonstrate the accuracy...
In this paper we propose a new concept of quasi-uniform monotonicity weaker than the uniform monotonicity which has been developed in the study of nonlinear operator equation $Au=b$. We prove that if $A$ is a quasi-uniformly monotone and hemi-continuous operator, then $A^{-1}$ is strictly monotone, bounded and continuous, and thus the Galerkin approximations converge. Also we show an application of a quasi-uniformly monotone and hemi-continuous operator to the proof of the well-posedness and convergence...
We analyze a numerical model for the Signorini unilateral contact, based on the mortar method, in the quadratic finite element context. The mortar frame enables one to use non-matching grids and brings facilities in the mesh generation of different components of a complex system. The convergence rates we state here are similar to those already obtained for the Signorini problem when discretized on conforming meshes. The matching for the unilateral contact driven by mortars preserves then the proper...
Currently displaying 1101 –
1120 of
1415