In this paper, the bisection of the local mesh refinement in self adaptive finite element is applied to the obstacle problem of elliptic variational inequalities .We try to find the approximated region of the contact in the obstacle problem efficiently .Numerical examples are given for the obstacle problem. Key-Words: obstacle problem, variational inequalities, self adaptive finite element, bis...

This paper introduces an approach to visual sampling and reconstruction motivated by concepts from numerical grid generation. We develop adaptive meshes that can nonuniformly sample and reconstruct intensity and range data. Adaptive meshes are dynamic models which are assembled by interconnecting nodal masses with adjustable springs. Acting as mobile sampling sites, the nodes observe interestin...

SUMMARY We present a parallel goal-oriented adaptive finite element method that can be used to rapidly compute highly accurate solutions for 2.5D controlled-source electromagnetic (CSEM) and 2D magnetotelluric (MT) modeling problems. We employ unstructured triangular grids that permit efficient discretization of complex modeling domains such as those containing topography, dipping layers and mu...

In this paper we define a new bi-adaptive mesh denoising algorithm for efficient features preserving restoration of noisy models acquired from 3D scanners. The new filter is based on two recently introduced adaptive algorithms for triangle mesh denoising which show good results over previous methods. We adapt the MMSE filter noise threshold adaptive equation to compute new triangles normal vect...

The solution of partial differential equations (PDEs) with disparate space and time scales often benefit from the use of nonuniform meshes and adaptivity to successfully track local solution features. In this paper we consider the problem of grid generation using the so– called equidistribution principle (EP) [3] and domain decomposition (DD) strategies. In the time dependent case, the EP is us...

In this paper we study adaptive mesh refinement (AMR) for elliptic and hyperbolic systems. We use the Asynchronous Fast Adaptive Composite Grid Method (AFACx) [4], a parallel algorithm based upon the of Fast Adaptive Composite Grid Method (FAC) [5] as a test case of an adaptive elliptic solver. For our hyperbolic system example we use TVD and EN0 schemes for solving the Euler and MHD equations ...

This paper presents a real-time rendering technique for dynamic, incremental 3D mesh refinement. The technique can be applied to any triangulated 3D mesh with arbitrary topology and connectivity. The functionality relies on geometry shaders that are used to amplify or remove geometry based on precalculated refinement patterns. For each triangle, the instantiated refinement pattern is selected d...

The development of adaptive mesh refinement capabilities in the field of computational fluid dynamics is an essential tool for enabling the simulation of larger and more complex physical problems. In this report, we describe recent developments that have been made to enable adaptive mesh refinement in Nek5000 and we validate the method on simple, two–dimensional, steady test cases. We start by ...

Abstract We consider a second-order elliptic boundary value problem with strongly monotone and Lipschitz-continuous nonlinearity. design study its adaptive numerical approximation interconnecting finite element discretization, the Banach–Picard linearization, contractive linear algebraic solver. In particular, we identify stopping criteria for solver that on one hand do not request an overly ti...

For the Poisson problem in two dimensions, we consider the standard adaptive finite element loop solve, estimate, mark, refine, with estimate being implemented using the p-robust equilibrated flux estimator, and, mark being Dörfler marking. As a refinement strategy we employ p-refinement. We investigate the question by which amount the local polynomial degree on any marked patch has to be incre...