In an adaptive grid, the physics of the problem at hand must ultimately direct the grid points to distribute themselves so that a functional relationship on these points can represent the physical solution with sufficient accuracy. The idea is to have the grid points move as the physical solution develops, concentrating in regions of large variation in the solution as they emerge. The mathemati...

For Computation of fluid-solid interfaces, which is one of the most challenging classes of problems in computational engineering and sciences, has been receiving much attention in recent years. The numerical challenges include (i) accurate representation of the flow field near the interface, (ii) accurate advection of the vortices, (iii) grid generation and motion, (iv) robustness and accuracy ...

A 26-year-old male intravenous drug user (IDU) presented twice within 6 months with relapsed polymicrobial infective endocarditis (IE) due to Eikenella corrodens and Streptococcus constellatus after completing two courses of appropriate antimicrobial therapy. This report points to relapsing endocarditis as a clinical entity that warrants attention in IDUs when E. corrodens or S. constellatus ar...

In this paper we consider the problem of bootstrapping a class of spatial regression models when the sampling sites are generated by a (possibly nonuniform) stochastic design and are irregularly spaced. It is shown that the natural extension of the existing block bootstrap methods for grid spatial data does not work for irregularly spaced spatial data under nonuniform stochastic designs. A vari...

This thesis first discusses the design, fabrication, and test results of UHF preamplifier designed to operate from 400 to 500 MHz. The preamplifier integrates a single-pole double-throw (SPDT) switch, tapped-line interdigital filter, balanced lownoise amplifier, and gain stage in a compact, multilayer package. The switch and amplification stages are realized on one layer, and the stripline filt...

Nearpt3 is an algorithm and implementation to preprocess more than 10 fixed points in E and then perform nearest point queries against them. With fixed and query points drawn from the same distribution, Nearpt3’s expected preprocessing and query time are θ(1) per point, with a very small constant factor. The data structure is a uniform grid in E, typically with the same number of grid cells as ...

We prove a conjecture of Ambrus, Ball and Erdélyi that equally spaced points maximize the minimum of discrete potentials on the unit circle whenever the potential is of the form n X

The traditional K-means clustering algorithm is difficult to initialize the number of clusters K, and the initial cluster centers are selected randomly, this makes the clustering results very unstable. Meanwhile, algorithms are susceptible to noise points. To solve the problems, the traditional K-means algorithm is improved. The improved method is divided into the same grid in space, according ...

Techniques are presented for distributing grid points on parametric surfaces and in volumes according to a speci ed distribution of arc length. Interpolation techniques are introduced which permit a given distribution of grid points on the edges of a three-dimensional grid block to be propagated through the surface and volume grids. Examples demonstrate how these methods can be used to improve ...

We provide a maximum norm analysis of an overlapping Schwarz method on nonmatching grids for second-order elliptic obstacle problem. We consider a domain which is the union of two overlapping subdomains where each subdomain has its own independently generated grid. The grid points on the subdomain boundaries need not match the grid points from the other subdomain. Under a discrete maximum princ...