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Search Publications by: Raghu N Kacker (Fed)

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Displaying 126 - 150 of 187

A More General Type A Evaluation

September 9, 2010
Author(s)
Ruediger Kessel, Raghu N. Kacker, Klaus-Dieter Sommer
The evaluation of uncertainty according to the Guide to the Expression of Uncertainty in measurement is the internationally agreed procedure to evaluate the complete result statement in measurement including measurement uncertainty. It distinguishes two

Metrological Compatibility and Statistical Consistency

September 5, 2010
Author(s)
Raghu N. Kacker, Ruediger Kessel, Klaus-Dieter Sommer, Xin Bian
The traditional concept of consistency in multiple evaluations of the same measurand is statistical. The statistical view of consistency does not match the modern view of uncertainty in measurement; in particular, it does not apply to the results of

Uncertainty Budgeting for Range Calibration

May 10, 2010
Author(s)
Ruediger Kessel, Raghu N. Kacker, Klaus-Dieter Sommer
The Guide to the Expression of Uncertainty (GUM) in Measurement established a general procedure to evaluate measurement uncertainty. The Guide covers only the evaluation of a single result or a set of results. Modern measurement instruments and procedures

Significance Test in Operational ROC Analysis

April 5, 2010
Author(s)
Jin Chu Wu, Alvin F. Martin, Raghu N. Kacker, Robert C. Hagwood
To evaluate the performance of fingerprint-image matching algorithms on large datasets, a receiver operating characteristic (ROC) curve is applied. From the operational perspective, the true accept rate (TAR) of the genuine scores at a specified false

A Combinatorial Approach to Building Navigation Graphs for Dynamic Web Applications

September 20, 2009
Author(s)
Raghu N. Kacker, David R. Kuhn, James F. Lawrence, Wenhua Wang, Yu Lei, Sreedevi Sampath
Modeling the navigation structure of a dynamic web application is a challenging task because of the presence of dynamic pages. In particular, there are two problems to be dealt with: (1) the page explosion problem, i.e., the number of dynamic pages may be

Scaling Factors and Uncertainties for ab Initio Anharmonic Vibrational Frequencies

August 21, 2009
Author(s)
Russell D. Johnson III, Karl K. Irikura, Raghu N. Kacker, Ruediger Kessel
To predict the vibrational spectra of molecules, ab initio calculations are often used to compute harmonic frequencies, which are usually scaled by empirical factors as an approximate correction for errors in the force constants and for anharmonic effects

Combinatorial Software Testing

August 7, 2009
Author(s)
David R. Kuhn, Raghu N. Kacker, Yu Lei, Justin Hunter
Developers of large data-intensive software often notice an interesting - though not surprising - phenomenon: when usage of an application jumps dramatically, components that have operated for months without trouble suddenly develop previously undetected

Uncertainties in Scaling Factors for ab Initio Vibrational Zero-Point Energies

March 21, 2009
Author(s)
Karl K. Irikura, Russell D. Johnson III, Raghu N. Kacker, Ruediger Kessel
Vibrational zero-point energies (ZPEs) determined from ab initio calculations are often scaled by empirical factors. An empirical scaling factor partially compensates for the effects arising from vibrational anharmonicity and incomplete treatment of

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

A Method to Quantify Uncertainty Due to Bias in Chemical Analyses

October 16, 2008
Author(s)
Raghu N. Kacker
A widely accepted approach to assure that the certified property of a chemical reference material is independent of the method of analysis is to analyze by two or more judiciously chosen methods. The statistical problem then is to determine the consensus

On-Line Process Control

October 16, 2008
Author(s)
Raghu N. Kacker, Nien-Fan Zhang
The natural state of manufacturing and measurement processes is usually nonstationary. The methods of statistical process control (SPC) are therefore inappropriate for on-line control. This paper provides a simple and generic protocol for on-line control

Why and When Should One Calibrate a Measurement System

October 16, 2008
Author(s)
Raghu N. Kacker
A measurement without its uncertainty is not adequate. The stated uncertainty ceases to be valid when the measurement system goes out of calibration. A conventional re-calibration interval may not be optimal for all usage conditions. The cost of re

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 $t$)

Automated Combinatorial Test Methods: Beyond Pairwise Testing

June 2, 2008
Author(s)
David R. Kuhn, Raghu N. Kacker, Yu Lei
Pairwise testing has become a popular approach to software quality assurance because it often provides effective error detection at low cost. However, pairwise (2-way) coverage is not sufficient for assurance of mission-critical software. Combinatorial