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Displaying 1 - 25 of 35

On Computing Elastic Shape Distances between Curves in d-dimensional Space

June 21, 2021
Author(s)
Javier Bernal, James F. Lawrence, Gunay Dogan, Robert Hagwood
The computation of the elastic registration of two simple curves in higher dimensions and therefore of the elastic shape distance between them has been investigated by Srivastava et al. Assuming the first curve has one or more starting points, and the

Measurement of mass of aerosol particles

January 1, 2021
Author(s)
Kevin J. Coakley, Robert Hagwood, Kensei Ehara, Nobuhiko FUKUSHIMA, Kittichote WORACHOTEKAMJORN, Naoko TAJIMA, Hiromu SAKURAI
An aerosol particle mass analyzer (APM) which classifies aerosol particles according to their mass has been developed. Mass distributions of aerosol particles can be measured by the APM combined with a particle counting device. Particle mass that can be

Certification of Standard Reference Material(R) 955d, Toxic Elements and Metabolites in Frozen Human Blood

October 15, 2020
Author(s)
Lee L. Yu, Karen E. Murphy, Colleen E. Bryan Sallee, Thomas W. Vetter, Robert C. Hagwood, George C. Caceres, Stephen E. Long, J M. Jarrett, M A. Franklin, J Castro Georgi, D M. Jones, Robert Jones, Z Li, Y L. Sommer, D S. Tevis, K Wallon, C D. Ward, M Maras, S Erdahl, C Gilmer, M Wermers, H Woldeysus, K F. Mehigan, M Morrissette, Christopher D. Palmer, Patrick J. Parsons
Standard Reference Material (SRM) 955d is intended for use in validating analytical methods for measuring toxic elements and mercury species in human blood, and in value assigning locally produced control materials analyzed using the validated methods. A

Measurement of mass of aerosol particles

October 30, 2019
Author(s)
Kevin J. Coakley, Robert C. Hagwood, Kensei Ehara, Nobuhiko Fukushima, Kittichote Worachotekamjorn, Naoko Tajima, Hiromu Sakurai
An aerosol particle mass analyzer (APM) which classifies aerosol particles according to their mass has been developed. Mass distributions of aerosol particles can be measured by the APM combined with a particle counting device. Particle mass that can be

Optimal Dynamic Spectrum Access Scheme for Utilizing White Space in LTE Systems

April 15, 2019
Author(s)
Anirudha Sahoo, Timothy Hall, Robert C. Hagwood
In this study, we design and implement an algorithm for optimal dynamic spectrum access (DSA) in a shared spectrum system where the primary user (PU) is a Long Term Evolution (LTE) system. The cumulative hazard function from survival analysis is used to

Dynamic Spectrum Access Algorithms Based on Survival Analysis

December 20, 2017
Author(s)
Timothy Hall, Anirudha Sahoo, Robert C. Hagwood, Sarah B. Streett
In this study, we design and implement two algorithms for dynamic spectrum access (DSA) that are based on survival analysis. They use a non-parametric estimate of the cumulative hazard function to predict the remaining idle time available for secondary

Fast Dynamic Programming for Elastic Registration of Curves

June 30, 2016
Author(s)
Javier Bernal, Gunay Dogan, Robert Hagwood
Curve registration problems in data analysis and com- puter vision can often be reduced to the problem of match- ing two functions defined on an interval. Dynamic Pro- gramming (DP) is an effective approach to solve this prob- lem. In this paper, we

Movement on Stairs During Building Evacuations

June 8, 2016
Author(s)
Richard D. Peacock, Paul A. Reneke, Erica D. Kuligowski, Robert C. Hagwood
The time that it takes an occupant population to reach safety when descending a stair during building evacuations is typically estimated by measureable engineering variables such as stair geometry, speed, stair density, and pre-observation delay. In turn

FFT-based Alignment of 2d Closed Curves with Application to Elastic Shape Analysis

September 10, 2015
Author(s)
Gunay Dogan, Javier Bernal, Robert Hagwood
For many shape analysis problems in computer vision and scientific imaging (e.g., computational anatomy, morphological cytometry), the ability to align two closed curves in the plane is crucial. In this paper, we concentrate on rigidly aligning pairs of

A Fast Algorithm for Elastic Shape Distances Between Closed Planar Curves

June 8, 2015
Author(s)
Gunay Dogan, Javier Bernal, Robert C. Hagwood
Effective computational tools for shape analysis are needed in many areas of science and engineering. We address this and propose a fast algorithm to compute the geodesic distance between elastic closed curves in the plane. The original algorithm for the

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