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Displaying 326 - 350 of 446

Bifurcations, Center Manifolds, and Periodic Solutions

January 15, 2009
Author(s)
David E. Gilsinn
Nonlinear time delay differential equations are well known to have arisen in models in physiology, biology, and population dynamics. They have also arisen in models of metal cutting processes. Machine tool chatter, from a process called regenerative

An Interaction-based Test Sequence Generation Approach for Testing Web Applications

December 3, 2008
Author(s)
Wenhua Wang, Sreedevi Sampath, Yu Lei, Raghu N. Kacker
Web applications often use dynamic pages that interact with each other by accessing shared objects, e.g., session objects. Interactions between dynamic pages need to be carefully tested, as they may give rise to subtle faults that cannot be detected by

Quantum Simulations of Classical Annealing Processes

September 26, 2008
Author(s)
Rolando Somma, S. Boixo, Howard Barnum, Emanuel Knill
We describe a quantum algorithm that solves combinatorial optimization problems by quantum simulation of a classical simulated annealing process. Our algorithm exploits quantum walks and the quantum Zeno effect induced by evolution randomization. It

Comparison of statistical consistency and metrological consistency

September 6, 2008
Author(s)
Raghu N. Kacker, Ruediger Kessel, Klaus-Dieter Sommer, Xin Bian
The conventional concept of consistency in multiple evaluations of the same measurand is based on statistical error analysis. This concept is based on regarding the evaluations as realizations from sampling probability distributions of potential

Refining the In-Parameter-Order Strategy for Constructing Covering Arrrays

September 1, 2008
Author(s)
Michael Forbes, James F. Lawrence, Yu Lei, Raghu N. Kacker, D. Richard Kuhn
Covering arrays are structures for well-representing extremely large input spaces and are used to efficiently implement blackbox testing for software and hardware. This paper proposes refinements over the In-Parameter-Order strategy (for arbitrary $t$)

Grain Size Distribution in Two Dimensions in the Long Time Limit

July 8, 2008
Author(s)
Geoffrey B. McFadden, C.S. Pande, K.P. Cooper
It is shown that the inclusion of a "noise" term in the growth rate of individual grains leads to a stochastic model that provides a more realistic description of grain growth phenomenon. The resulting Fokker-Planck equation for the grain size distribution

Tight Bounds for the Multiplicative Complexity of Symmetric Functions

April 28, 2008
Author(s)
Joan Boyar, Rene Peralta
The multiplicative complexity of a Boolean function f is defined as the minimum number of binary conjunction (AND) gates required to construct a circuit representing f , when only exclusive-or, conjunction and negation gates may be used. This article

IPOG/IPOG-D: Efficient Test Generation for Multi-way Combinatorial Testing

November 29, 2007
Author(s)
Yu Lei, Raghu N. Kacker, D. Richard Kuhn, Vadim Okun, James F. Lawrence
We present two strategies for multi-way testing (i.e., t-way testing with t > 2). The first strategy generalizes an existing strategy, called In-Parameter-Order, from pairwise testing to multi-way testing. This strategy requires all t-way combinations to

Evolution of Modern Approaches to Express Uncertainty in Measurement

November 27, 2007
Author(s)
Raghu N. Kacker, K D. Sommer, Bernd Siebert
The object of this paper is to discuss evolution of the concept of uncertainty in measurement and methods for its quantification from the classical error analysis to the modern approaches based on the Guide to the Expression of Uncertainty in Measurement

Modeling of Photochemical Reactions in a Focused Laser Beam

July 1, 2007
Author(s)
Fern Y. Hunt, Adolfas Gaigalas, Lili Wang
This paper presents a mathematical model of photodegradation of fluorophores passing through a laser beam. The beam is focused on the sample and thus the power distribution of incident light is strongly dependent on spatial location while the fluorophores

A Combinatorial Testing Strategy for Concurrent Programs

June 7, 2007
Author(s)
Yu Lei, Richard Carver, Raghu N. Kacker, David Kung
One approach to testing concurrent programs is called reachability testing, which derives test sequences automatically and on-the-fly, without constructing a static model. Existing reachability testing algorithms are exhaustive in that they are intended to

IPOG: A General Strategy for t-Way Software Testing

March 29, 2007
Author(s)
Yu Lei, Raghu N. Kacker, D. Richard Kuhn, Vadim Okun, James F. Lawrence
Most existing work on t-way testing has focused on 2-way (or pairwise) testing, which aims to detect faults caused by interactions between any two parameters. However, faults can also be caused by interactions involving more than two parameters. In this

Comments on 'Bayesian evaluation of comparison data' by Ignacio Lira

January 1, 2007
Author(s)
Raghu N. Kacker, Blaza Toman
A recent paper by Ignacio Lira in Metrologia 43 (2006) S231-S234 addresses a well-known problem in combining information from interlaboratory evaluations. Lira presents an expression, which he claims to be the kernel of a Bayesian posterior probability

Random-Effects Model for Meta-analysis of Clinical Trials: An Update

January 1, 2007
Author(s)
Rebecca DerSimonian, Raghu N. Kacker
The random-effects model is a useful approach for meta-analysis of clinical studies. It explicitly accounts for the heterogeneity of studies through a statistical parameter representing the inter-study variation. We discuss several iterative and non

Approximating Periodic Solutions of Autonomous Delay Differential Equations

November 30, 2006
Author(s)
David E. Gilsinn
Machine tool chatter has been characterized as isolated periodic solutions or limit cycles of delay differential equations. Determining the amplitude and frequency of the limit cycle is sometimes crucial to understanding and controlling the stability of

Integral Operators and Delay Differential Equations

October 1, 2006
Author(s)
David E. Gilsinn, Florian A. Potra
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
Displaying 326 - 350 of 446