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Displaying 1 - 25 of 70

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