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A lattice metric singualrity occurs when unit cells defining two (or more) lattices yield the identical set of unique calculated d-spacings. The existence of such singularities, therefore, has a practical and theoretical impact on the indexing of powder
The National Institute of Standards and Technology (NIST) is developing a digital library of mathematical functions to replace the widely used National Bureau of Standards Handbook of Mathematical Functions published in 1964 [1]. The NIST Digital Library
David E. Gilsinn, Geraldine S. Cheok, Alan M. Lytle
Automation of construction processes can result in reduced project costs and increased worker safety. A process that lends itself to automation is the picking and placing of objects. However, determining the pose (position and orientation) of an object is
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
Estimating error uncertainties arising in production parts isnot a well understood process. This study developed an approach to estimatethese uncertainties. Machine tool error components on a vertical turningcenter were measured. Multiple parts were
We begin this expository essay by reviewing with examples what a typical engineer already knows about statistics. We then consider a central question in engineering decision making, i.e., given a computer simulation of high-consequence systems, how do we
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
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.
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.
We compare leading statistical methods to combine information from independent similar studies using random effects model. One of the oldest methods is that of Cochran (1954). The method of Paule and Mandel (1982) was developed to determine the consensus
Fern Y. Hunt, Anthony J. Kearsley, Agnes A. O'Gallagher
Current methods for aligning biological sequences are based on dynamic programming algorithms. If large numbers of sequences or a number of long ones are to be aligned the required computations are expensive in memory and CPU time. In an attempt to bring
Fern Y. Hunt, Anthony J. Kearsley, Agnes A. O'Gallagher
Current methods for aligning biological sequences are based on dynamic programming algorithms. If large numbers of sequences or a number of long ones are to be aligned the required computations are expensive in memory and CPU time. In an attempt to bring
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
This paper responds to comments received by the authors on the paper, Combined Result and Associated Uncertainty from Interlaboratory Evaluations Based on the ISO Guide that appeared in Metrologia, 2002, 39, 279-293.
To intelligently and effectively use the crystallographic databases, dierse mathematical and computer tools are required that can delve into the nature of a given lattice or that can cut across a set of lattices to elucidate various types of interlatice
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
The Guide to the Expression of Uncertainty in Measurement recommends a standardized way of expressing uncertainty in measurement and provides a comprehensive approach for combining information to evaluate uncertainty in all kinds of measurements in science
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 (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
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
John T. Kelso, L E. Arsenault, Steven G. Satterfield, Peter M. Ketcham, R D. Kriz
We present DIVERSE, a highly modular collection of complementary software packages designed to facilitate the creation of device independent virtual environments. DIVERSE is free/open source software; an API (Application Programming Interface) written in C