U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Mathematics & Statistics

Search Publications

Search Title, Abstract, Conference, Citation, Keyword or Author
  • Published Date
Displaying 401 - 425 of 468

Tool Length-Dependent Stability Surfaces

April 20, 2004
Author(s)
T L. Schmitz, J C. Ziegert, Timothy J. Burns, Brian S. Dutterer, W R. Winfough
This paper describes the development of three-dimensional stability surfaces, or maps, that combine the traditional dependence of allowable (chatter-free) chip width on spindle speed with the inherent dependence on tool overhang length, due to the

Parallel Programming with Interoperable MPI

February 1, 2004
Author(s)
William L. George, John G. Hagedorn, J E. Devaney
In this article we describe IMPI (Interoperable Message Passing Interface), a message passing protocol that allows you to easily run parallel programs across multiple clusters, SMPs (symmetric multiprocessors), parallel machines, personal computers, and

Approximating Limit Cycles of a Van der Pol Equation with Delay

January 15, 2004
Author(s)
David E. Gilsinn
In this paper a theorem of Stokes is used to establish the existence of a periodic solution of a Van der Pol equation with fixed delay in the neighborhood of an approximating solution that satisfies a certain noncriticality condition.

Using Nonoscillatory Splines to Model Urban Environments

January 15, 2004
Author(s)
David E. Gilsinn, Marjorie A. McClain, Christoph J. Witzgall
In this paper we introduce the notion of Lavery splines and examine their properties in the univariate case. We also discuss some of the details involved with computing these splines on irregularly spaced data.

The Dilogarithm Function for Complex Argument

November 8, 2003
Author(s)
L C. Maximon
This paper summarizes the basic properties of the Euler dilogarithm function, often referred to as the Spence function. These include integral representations, series expansions, linear and quadratic transformations, functional relations, numerical values

Deconvolving LADAR Images Of Bar Codes for Construction Site Object Recognition

October 1, 2003
Author(s)
David E. Gilsinn, Geraldine S. Cheok, Dianne M. O'Leary
This report discusses a general approach to reconstructing ground truth intensity images of bar codes that have been distorted by LADAR optics. The first part of this report describes the experimental data collection of several bar code images along with

An Optimization Approach to Multiple Sequence Alignment

July 1, 2003
Author(s)
Fern Y. Hunt, Anthony J. Kearsley, H H Wan
The problem of multiple sequence alignment is recast as an optimization problem using Markov decision theory. One seeks to minimize the expected or average cost of alignment subject to data-derived constraints. In this setting the problem is equivalent to

NIST Digital Library of Mathematical Functions

May 1, 2003
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

Separating Signal From Noise in Global Warming

March 12, 2003
Author(s)
Bert W. Rust
One argument often used against global warming is that the global temperature record is too noisy to allow a clear determination of the signal. This paper presents two models for the signal which suggest that: (1) the warming is accelerating, (2) the

Algorithms and Codes for the Macdonald Function: Recent Progress and Comparisons

February 1, 2003
Author(s)
B R. Fabijonas, Daniel W. Lozier, J M. Rappoport
The modified Bessel function K iŅχ, also known as the Macdonald function, finds application in the Kontorovich-Lebedev integral transform when χ and Ņ are real and positive. In this paper, a comparison of three codes for computing this function is made

Dealing with Degeneracy in Triangulation

November 1, 2002
Author(s)
Francis Sullivan, Isabel M. Beichl
This is a tutorial article on a quick method for dealing with degeneracy in geometric computations with specific reference to triangulation. The type degeneracy targeted by this article that of four or more points on a circle and five or more points on a

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
Was this page helpful?