We apply a new industrial strength numerical approximation, called the “mesh-free adjoint method,” to solve the nonlinear filtering problem. This algorithm exploits the smoothness of the problem, unlike particle filters, and hence we expect that mesh-free adjoints are superior to particle filters for many practical applications. The nonlinear filter problem is equivalent to solving the Fokker-P...

We describe a sculpting system for designing free-form polygonal models using virtual sculpting tools and mesh refinement operations. Virtual tools are geometric objects with shapes described by superquadric equations. The user controls a virtual tool to sculpt a free-form polygonal model starting from a mesh. The vertices of the mesh respond to a tool in a semi-realistic manner, allowing the u...

This presentation will highlight the computational techniques we are developing for simulating incompressible free-surface flows using the Spectral Element Method (SEM) [9, 10]. These techniques include the arbitrary Lagrangian-Eulerian (ALE) formulation [2,3,5,11], mesh update and re-meshing methods [4, 7]. A brief introduction will be devoted to recalling the physical problem and its Navier-S...

Least squares kinetic upwind mesh-free (LSKUM) method has been the subject of research over twenty years in our research group. LSKUM method requires a cloud (W) of points or nodes and connectivity N(P 0 ) for every 0 P Î W . The connectivity of P0 is a set of neighbours 0 ( ) i P N P Î of P0. The cloud can be a simple cloud, Cartesian cloud or chimera cloud or can be obtained rapidly using adv...

|We are often required to generate a Delaunay mesh whose element size is within a constant factor of a control spacing function, i.e., well-conformed, in addition to the fact that each mesh element has small aspect ratio, i.e., well-shaped. However, generating wellshaped Delaunay meshes is an open problem for a long time. Observe that slivers have small radius-edge ratio thus the Delaunay trian...

We want to compute geometric shortest paths in a collection of convex traversable polygons, also known as a navigation mesh. Simple to compute and easy to update, navigation meshes are widely used for pathfinding in computer games. When the mesh is static, shortest path problems can be solved exactly and very fast but only after a costly preprocessing step. When the mesh is dynamic, practitione...

aims: the installation of intravenous catheter is an unpleasant and painful experience for many patients. then, it is necessary to provide new methods to either reduce or remove pain in the patients’ injection point. the aim of this study was to investigate the effects of positioning (either sitting or lying) during the installation of intravenous catheter on pain level and the following anxiet...

In this paper, a mesh-free approach called smooth particle hydrodynamics (SPH) is proposed to analyze the seepage problem in porous media. In this method, computational domain is discredited by some nodes, and there is no need for background mesh; therefore, it is a truly meshless method. The method was applied to analyze seepage flow through a concrete dam foundation. Using the SPH method, the...

In this paper, the applications of mesh-free SPH (Smoothed Particle Hydrodynamics) methodology to the simulation and analysis of 3-D hard machining process is presented. A Langrangian SPH based model is carried out using the Ls-Dyna software. Classical Lagrangian, Eulerian and ALE methods such as finite element methods (FEM) cannot resolve the large distortions very well. Conventional finite el...

OBJECTIVE To investigate a new approach for query expansion based on retrieval feedback. The first objective in this study was to examine alternative query-expansion methods within the same retrieval-feedback framework. The three alternatives proposed are: expansion on the MeSH query field alone, expansion on the free-text field alone, and expansion on both the MeSH and the free-text fields. Th...