This paper presents a general mesh refinement method based on a density function for distributing the grid points, which can be used for solving optimal control problems through a direct method. The algorithm captures any discontinuities and smoothness irregularities in the state and control variables with high resolution, thus helping with the convergence of the overall optimization algorithm....

In the context of computer assist surgical techniques, a new elastic registration method of 3D meshes is presented. In our applications, one mesh is a high density mesh (30000 vertexes), the second is a low density one (1000 vertexes). Registration is based upon the minimisation of a symmetric distance between both meshes, defined on the vertexes, in a multi resolution approach. Results on synt...

The paper presents a numerical and experimental study of corona discharge for a blade -plate configuration. Finite element method (FEM) is used to determine the electric potential between the electrodes and charge conservation equation is solved by the method of characteristics (MOC) to determine the charge density. The structured mesh is redefined at each step of the iterative scheme, the node...

One of the key advantages of mesh networks over cellular-based networks is that mesh nodes are relatively inexpensive. Hence, it is economically feasible to spread mesh nodes at a high enough density to provide high data rates to a dense user population. Speci cally, the high node density results is a short distance between receivers and transmitters, and hence high SNR channels and high bit-ra...

A robust non-rigid registration method has been developed to deform a pelvis model to match with anatomical structures in a CT image. A statistical volumetric model is constructed from a collection of training CT datasets. The model is represented as a hierarchical tetrahedral mesh equipped with embedded Bernstein polynomial density functions on the barycentric coordinates of each tetrahedron. ...

The accuracy of the numerical result is closely related to mesh density as well as its distribution. Mesh plays a very significant role in the outcome of numerical simulation. Many nasal airflow studies have employed unstructured mesh and more recently hybrid mesh scheme has been utilized considering the complexity of anatomical architecture. The objective of this study is to compare the result...

We present for static density functional theory and time-dependent density functional theory calculations an all-electron method which employs high-order hierarchical finite-element bases. Our mesh generation scheme, in which structured atomic meshes are merged to an unstructured molecular mesh, allows a highly nonuniform discretization of the space. Thus it is possible to represent the core an...

Microbial electrolysis cells (MECs) provide a high-yield method for producing hydrogen from renewable biomass. One challenge for commercialization of the technology is a lowcost and highly efficient cathode. Stainless steel (SS) is very inexpensive, and cathodes made of this material with high specific surface areas can achieve performance similar to carbon cathodes containing a platinum cataly...

A 'fictitious boundary method' for computing incompressible flows with complicated small-scale and/or time-dependent geometric details is presented. The underlying technique is based on a special treatment of Dirichlet boundary conditions , particularly for FEM discretizations, together with so-called 'iterative filtering techniques' in the context of hierarchical multigrid approaches such that...

In this paper an improved automatic mesh generation method for FEA using a dynamic bubble system is presented. The proposed method features two separate routines; one for automatic generation of a set of nodes in accordance with the desired mesh density and the Second Newton's Law of dynamics, and one for automatic generation of nite elements according to the Delaunay algorithm and using a set ...