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Displaying 32101 - 32125 of 74178

Does Habituation Affect Fingerprint Quality?

February 20, 2007
Author(s)
Mary F. Theofanos, R J. Michaels, Jean C. Scholtz, Emile L. Morse, Peter May
Interest in the environmental factors that affect biometric image quality is increasing as biometric technologies are currently being implemented in various business applications. This study aims to determine, through repeated trials, the effects of

Firebrand Generation From Burning Vegetation

February 20, 2007
Author(s)
Samuel L. Manzello, Alexander Maranghides, William E. Mell
A series of real scale fire experiments were performed to determine the size and mass distribution of firebrands generated from Douglas-Fir (pseudotsuga menziesii) trees. The experiments were performed in the Large Scale Fire Laboratory (LFL) at NIST. The

Guide to Intrusion Detection and Prevention Systems (IDPS)

February 20, 2007
Author(s)
Karen A. Scarfone, Peter M. Mell
The National Institute of Standards and Technology (NIST) developed this document in furtherance of its statutory responsibilities under the Federal Information Security Management Act (FISMA) of 2002, Public Law 107-347. This publication seeks to assist

Guidelines on Electronic Mail Security

February 20, 2007
Author(s)
Miles C. Tracy, Wayne Jansen, Karen A. Scarfone, Jason Butterfield
This document was developed in furtherance of NIST's statutory responsibilities under the Federal Information Security Management Act (FISMA) of 2002, Public Law 107-347. The purpose of the publication is to recommend security practices for designing

Crystallization-Induced Fluid Flow in Polymer Melts Undergoing Solidification

February 19, 2007
Author(s)
Donghua Xu, Z G. Wang, Jack F. Douglas
The formation of semi-crystalline plastic polymer materials often occurs under confinement conditions where high pressure imprinting or casting in a mold are involved. To gain insight into this highly non-equilibrium process, we examine the nature of the

Verification of a Gas Mask Calibrant

February 19, 2007
Author(s)
Robert A. Fletcher, Jiann C. Yang, George W. Mulholland, R L. King, Michael R. Winchester, D Klinedinst, Jennifer R. Verkouteren, Thomas G. Cleary, David Buckingham, James J. Filliben

Precision Atomic Spectroscopy for Improved Limits on Variation of the Fine Structure Constant and Local Position Invariance

February 16, 2007
Author(s)
Tara M. Fortier, Jason Stalnaker, Scott A. Diddams, Neil Ashby, Luca Lorini, Windell Oskay, Marie Delaney, James C. Bergquist, Steven R. Jefferts, Thomas E. Parker, Thomas P. Heavner, Filippo Levi, Jon H. Shirley, Wayne M. Itano, Kyoungsik Kim, Leo W. Hollberg
We report tests of local position invariance (LPI) and the constancy of fundamental constants from measurements of the frequency ratio of the 282-nm $^{199}$Hg$^+$ optical clock transition to the ground state hyperfine splitting in $^{133}$Cs. Analysis of

Thermal Stability of Nb/a-NbxSi1-x/Nb Josephson Junctions

February 16, 2007
Author(s)
Burm Baek, Paul Dresselhaus, Samuel Benz
As a high resistivity normal metal barrier for superconducting Josephson junctions, metal-silicon alloys appear to be a good replacement for noble metals and have been applied to the development of quantum voltage standard circuits. We observed that the

Accurate color measurement methods for medical displays

February 15, 2007
Author(s)
Anindita Saha, Hongye Liang, Aldo Badano, Edward F. Kelley
We report on the characterization of two novel probes for measuring display color without contamination from other screen areas or off-normal emissions. The probes are characterized using a scanning slit method and a moving laser and LED arrangement. The

Conditioning of Flowing Multiphase Samples for Chemical Analysis

February 15, 2007
Author(s)
Thomas J. Bruno
The chemical analysis of process streams is a common task that must be completed thousands of times every day in the chemical industry. In refineries, at gas wells, in chemical processing plants and in fine pharmaceutical facilities, there is a continual

Metal Complexes and Free Radical Toxicity Derived From Pfiesteria piscicida

February 15, 2007
Author(s)
Peter D. Moeller, Kevin Beauchesne, Kevin Huncik, William Davis, Steven J. Christopher, Andrew Gelasco, Pamela Riggs-Gelasco
Pfiesteria piscicida represents one of many dinoflagellate species inhabiting inter-coastal waterways and estuaries. This organism has been implicated in the production of a potent ichthyotoxin affecting estuarine fish as well as humans. The presence of

Osteocyte Enhancement of Angiogenesis In Vitro

February 14, 2007
Author(s)
Erica Takai, Juan M. Taboas, Rocky Tuan, Steven D. Hudson
It is well known that an intimate relationship exists between vascularization and bone formation during development and fracture healing, where new bone formation is preceded by local vascularization. A recent rat exercise model has demonstrated that

Solvation Structure of Ions in Water

February 14, 2007
Author(s)
Raymond D. Mountain
Molecular dynamics simulations of ions in water are reported for solutionsof varying solute concentration at ambient conditions for6 cations and 4 anions in 10 solutes. The solutes were selected to show trends inproperties as the size and charge density of

120Hz Pulse Tube Cryocooler for Fast Cooldown to 50K

February 13, 2007
Author(s)
Srinivas Vanapalli, Michael A. Lewis, Zhihua Gan, Ray Radebaugh
A pulse tube cryocooler operating at 120 Hz with 3.5 MPa average pressure achieved a no-load temperature of about 49.9 K and a cooldown time to 80 K of 5.5 minutes. The net refrigeration power at 80 K was 3.35 W with an efficiency of about 22.6% of Carnot

Effects of Vacancies on Properties of Relaxor Ferroelectrics: A First-Principles Study

February 13, 2007
Author(s)
L Bellaiche, Jorge Iniguez, Eric J. Cockayne, Benjamin P. Burton
A first-principles-based model is developed to investigate the influence of lead vacancies on the properties of relaxor ferroelectric Pb(Sc1/2Nb1/2)O3 (PSN). Lead vacancies generate large, inhomogeneous, electric fields that reduce barriers between energy
Displaying 32101 - 32125 of 74178