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Displaying 401 - 425 of 446

Reconstructing Images of Bar Codes for Construction Site Object Recognition

September 1, 2002
Author(s)
David E. Gilsinn, Geraldine S. Cheok, Dianne M. O'Leary
This paper discusses a general approach to reconstructing ground truth intensity images of bar codes that have been distorted by LADARoptics. The first part of this paper describes the experimental data collection of several bar code images along with

The Relegation Algorithm

March 3, 2001
Author(s)
A Deprit, E Deprit, Jesuus Palacian
Given a perturbed Hamiltonian system, normalization yields a Lie transformation which converts the main part of the Hamiltonian into an integral of the transformed system. An extension of the normalization method--the relegation algorithm--does the same

Constructing Sibson Elements for a Rectangular Mesh

February 1, 2001
Author(s)
David E. Gilsinn
This paper documents the construction of a finite element, called the Sibson element. The shape function of this element is formed on rectangular grids by C 1 splines defined on a triangulation of each subrectangle by dividing it into four subtriangles

Analytic Continuation, Singular Value Expansions, and Kramers-Kronig Analysis

January 17, 2001
Author(s)
Andrew M. Dienstfrey, L Greengard
We describe a systematic approach to the recovery of a function analytic in the upper half plane, ${\bfC:^+$, from measurements over a finite interval on the real axis, $D\subset {\bfR}$. Analytic continuation problems of this type are well-known to ill

Direct Blind Deconvolution II. Substitute Images and the Beak Method

November 1, 2000
Author(s)
Alfred S. Carasso
The BEAK method is an FFT-based direct blind deconvolution technique previously introduced by the author, and applied to a limited but significant class of blurs that can be expressed as convolutions of 2-D symmetric L vy probability density functions

Attractors, Chain Transitive Sets and Invariant Measures

September 15, 2000
Author(s)
Fern Y. Hunt
This paper discusses an easy to implement procedure for approximating the long time behavior of iterates of maps. Applications include to finding the roots of a complex polynomial and approximating attractors. The method uses the theory of Markov chains.

Zoltan: Data-Management Services For Parallel Applications Developer's Guide

June 30, 2000
Author(s)
K Devine, B Hendrickson, E Boman, M St. John, C Vaughan, William F. Mitchell
The Zoltan Dynamic Load-Balancing Library provides critical capability to a number of parallel applications. Zoltan includes a suite of algorithms for dynamically computing partitions of problems over sets of processors; geometric, tree-based and graph

Zoltan: Data-Management Services For Parallel Applications; User's Guide

June 30, 2000
Author(s)
K Devine, B Hendrickson, E Boman, M St. John, C Vaughan, William F. Mitchell
The Zoltan Dynamic Load-Balancing Library provides critical capability to a number of parallel applications. Zoltan includes a suite of algorithms for dynamically computing partitions of problems over sets of processors; geometric, tree-based and graph

On the Bifurcation From Continuous to Segmented Chip Formation in Metal Cutting

February 6, 2000
Author(s)
Timothy J. Burns, Matthew A. Davies, Christopher J. Evans
We describe a new approach to modeling chip formation in orthogonal machining. Metal cutting is interpreted as a nonlinear dynamical process with thermomechanical feedback, which is similar in many ways to an open chemical reactor. As the cutting speed is

The DLMF Project: A New Initiative in Classical Special Functions

June 1, 1999
Author(s)
Daniel W. Lozier
NIST (formerly, National Bureau of Standards) has started an ambitious project that aims to produce a successor to Abramowitz and Stegun's {\em Handbook of Mathematical Functions}, published by the National Bureau of Standards in 1964 and reprinted by

Stable Quasicrystalline Sphere Packing

March 1, 1999
Author(s)
Eric J. Cockayne, M Mihalkovic
Wills (1990, J. Phys., Paris 51, 1061), found a method relating certain decagonal disk packings to decagonal sphere packings with high packing fractions. Applying this technique to the decagonal rectangle-triangle tiling generated by inflation, we obtain a

On The Reversion of an Asymptotic Expansion and the Zeros of the Airy Functions

January 15, 1999
Author(s)
Bruce R. Fabijonas, Frank W. Olver
The general theories of the derivation of inverses of functions from their power series and asymptotic expansions are discussed and compared. The asymptotic theory is applied to obtain asymptotic expansions of the zeros of the Airy functions and their
Displaying 401 - 425 of 446