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Displaying 26 - 50 of 70

Movement on Stairs During Building Evacuations

September 25, 2014
Author(s)
Erica D. Kuligowski, Richard Peacock, Paul A. Reneke, Emily A. Wiess, Jason D. Averill, Robert Hagwood, Enrico Ronchi, Bryan Hoskins, Michael Spearpoint
The time that it takes an occupant population to reach safety when descending a stairwell during building evacuations is typically described by measureable engineering variables such as stairwell geometry, speed, density, and pre-evacuation delay. In turn

Testing Equality of Cell Populations Based on Shape and Geodesic Distance

December 3, 2013
Author(s)
Robert C. Hagwood, Javier Bernal, Michael W. Halter, John T. Elliott
Image cytometry has emerged as a valuable in-vitro screening tool and advances in automated microscopy have made it possible to readily analyze large cellular populations of image data. A statistical procedure to study homogeneity of such data is addressed

Development of a Standard Reference Material for Metabolomics Research

November 4, 2013
Author(s)
Karen W. Phinney, Guillaume Ballihaut, Mary Bedner, Johanna Camara, Steven J. Christopher, William C. Davis, Nathan G. Dodder, Brian E. Lang, Stephen E. Long, Mark S. Lowenthal, Elizabeth A. McGaw, Karen E. Murphy, Bryant C. Nelson, Jocelyn L. Prendergast, Jessica L. Reiner, Catherine A. Rimmer, Lane C. Sander, Michele M. Schantz, Katherine E. Sharpless, Lorna T. Sniegoski, Susan S. Tai, Jeanice M. Brown Thomas, Thomas W. Vetter, Michael J. Welch, Stephen A. Wise, Laura J. Wood, William F. Guthrie, Robert C. Hagwood, Stefan D. Leigh, James H. Yen, Nien F. Zhang, Madhu Chaurhary-Webb, Huiping Chen, Bridgette Haynes, Donna J. LaVoie, Leslie F. McCoy, Shahzad S. Momin, Neelima Paladugula, Elizabeth C. Pendergrast, Christine M. Pfeiffer, Carissa D. Powers, Zia Fazili-Qari, Daniel Rabinowitz, Michael E. Rybak, Rosemary L. Schleicher, Mary Xu, Mindy Zhang, Arthur L. Castle, Brandi S. Benford, Gauthier Eppe

Evaluation of Segmentation Algorithms on Cell Populations Using CDF Curves

February 24, 2012
Author(s)
Robert C. Hagwood, Javier Bernal, Michael W. Halter, John T. Elliott
Cell segmentation is a critical step in the analysis pipeline for most imaging cytometry experiments and the segmentation algorithm can effect the quantitative data derived from image analysis. Methods to evaluate segmentation algorithms are important for

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

Dynamics of DNA Through a Nanopore

October 16, 2008
Author(s)
Robert Hagwood
Single stranded DNA is modeled as a flexible polymer. The motion of such DNA in a vessel partitioned by a membrane containing a cylindrical nanopore is modeled. Statistical quantities such as the probability that a polymer end is at the pore entrance at

Uncertainty Analysis for Virtual Cement Measurement

September 13, 2006
Author(s)
Blaza Toman, Adriana Hornikova, Robert C. Hagwood, Hung-Kung Liu, Nien F. Zhang, Edward J. Garboczi, Jeffrey W. Bullard
Virtual measurements are the outputs of well-defined mathematical models based on theoretical principles and simulation algorithms. The VCCTL (Virtual Cement and Concrete Testing Laboratory) is a software system built by the Material and Construction

Analysis of Sensitivity of VCCTL Measurements to Various Input Quantities

August 9, 2006
Author(s)
Adriana Hornikova, Blaza Toman, Nien F. Zhang, Hung-Kung Liu, Robert C. Hagwood, Edward J. Garboczi, Jeffrey W. Bullard
Virtual measurements are the outputs of well-defined mathematical models based on theoretical principles and simulation algorithms. The VCCTL (Virtual Cement and Concrete Testing Laboratory) is a software system built by the Material and Construction

Measurement of 100 nm and 60 nm Particle Standards by Differential Mobility Analysis

August 1, 2006
Author(s)
George W. Mulholland, Michelle K. Donnelly, Robert C. Hagwood, S R. Kukuck, Vincent A. Hackley, D Y. Pui
The peak particle size and expanded uncertainties (95 % confidence interval) for two new particle calibration standards are measured as 101.60 nm ? 1.02 nm and 60.68 nm ? 0.59 nm. The particle samples are polystyrene spheres suspended in filtered

Combining Data in Small Multiple Method Studies

May 1, 2003
Author(s)
Robert C. Hagwood, William F. Guthrie
In this article an accurate confidence interval is derived when the results of a small number of different experimental methods are combined for the determination of an unknown quantity. ANOVA and a simple hierarchical Bayesian analysis of variance result