An adaptive mesh refinement method for solving optimal control problems is developed. The method employs orthogonal collocation at Legendre-Gauss-Radau points, and adjusts both the mesh size and the degree of the approximating polynomials in the refinement process. A previously derived convergence rate is used to guide the refinement process. The method brackets discontinuities and improves sol...

PURPOSE To compare fibroplasia and the resistance of the abdominal wall when polypropylene meshes and polypropylene/poliglecaprone are used. METHODS Seventy-seven male Wistar rats were divided into three groups: Control Group (for resistance); Group E (polypropylene mesh); and Group U (polypropylene/poliglecaprone mesh). The animals in Groups E and U had a standard muscular and aponeurotic de...

The shallow water equations are solved using a mesh of polygons on the sphere, which adapts infrequently to the predicted future solution. Infrequent mesh adaptation reduces the cost of adaptation and load-balancing and will thus allow for more accurate mapping on adaptation. We simulate the growth of a barotropically unstable jet adapting the mesh every 12 h. Using an adaptation criterion base...

The user has selected non-neutral expression 8 (Figure 1 bottom right). Here the user is inspecting the ground-truth scan data, with the expression 8 detail maps applied to the full-resolution geometry. Note that the expression data is in fact shown here in wireframe mode, though it appears solid due to the density of the data. There is a substantial difference in resolution between the origina...

Mesh modeling is an important problem with many applications in image processing. A key issue in mesh modeling is how to generate a mesh structure that well represents an image by adapting to its content. We propose a new approach to mesh generation, which is based on a theoretical result derived on the error bound of a mesh representation. In the proposed method, the classical Floyd-Steinberg ...

The objective of the present study was to learn more about the effect of seeding and loading techniques on the osteogenic differentiation in vitro of rat bone marrow cells into titanium fiber mesh. This material was used as received or subjected to glow discharge treatment (RFGD). The seeding methods that were used included a so-called droplet, cell suspension (high and low cell density), and r...

| A new reenement strategy is proposed for use in an adaptive procedure. The method developed places new nodes in regions of high solution error such that the beneet of the Delaunay re-triangulation algorithm is fully realised. Results show that the improved mesh geometry obtained with this method compared with the conventional centroid approach produces a more eecient mesh, where less nodes ar...

We present a new algorithm for combining a fully anisotropic goal-oriented mesh adaptation with the transient fixed point method for unsteady problems. The minimization of the error on a functional provides both the density and the anisotropy (stretching) of the optimal mesh. This method is used for specifying the mesh for a time subinterval from the state and the adjoint. The global transient ...

This paper describes a new technique for the triangulation of parametric surfaces. Most earlier methods sample the parameter domain, and the wrong choice of parameterization can spoil the triangulation or even cause the algorithm to fail. Conversely, we use a local tessellation primitive to sample and triangulate the surface. The sampling is almost uniform and the parameterization becomes irrel...

The computation of a six-dimensional density matrix is the crucial step for the evaluation of kinetic energy in electronic structure calculations. For molecules with heavy nuclei, one has to consider a very refined mesh in order to deal with the nuclear cusps. This leads to high computational time and needs huge memory for the computation of the density matrix. To reduce the computational compl...