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Displaying 7301 - 7325 of 9858

A Simple Reaction Time Scale for Under-Resolved Fire Dynamics

June 20, 2011
Author(s)
Randall J. McDermott, Kevin B. McGrattan, Jason E. Floyd
A reaction time scale model is developed for use in the eddy dissipation concept (fast chemistry limit) closure of the mean chemical source term in large-eddy simulation of fires. The novel aspect of the model is to consider a scaling regime for coarse

Intrusion Detection and Prevention Systems

October 22, 2010
Author(s)
Karen A. Scarfone, Peter M. Mell
Intrusion detection is the process of monitoring the events occurring in a computer system or network and analyzing them for signs of possible incidents. An intrusion detection and prevention system (IDPS) is software that automates the intrusion detection

Uncertainty calculation for spectral-responsivity measurements

September 1, 2009
Author(s)
John H. Lehman, Chih-Ming Wang, Marla L. Dowell, Joshua A. Hadler
This paper discusses a procedure for measuring the absolute spectral responsivity of optical-fiber power meters and computation of the calibration uncertainty. The procedure reconciles measurement results associated with a monochromator-based measurement

Coherent Rayleigh Scattering

October 16, 2008
Author(s)
J H. Grinstead, P F. Barker
Nonresonant four-wave mixing in rarefied gases in which the nonlinearity arises from microscopic velocity perturbations induced by electrostriction has been analyzed theoretically and experimentally. The spectral distribution of the signal beam was

Complementary Experimental Techniques for Multi-Scale Modeling of Plasticity

October 16, 2008
Author(s)
Lyle E. Levine, Gabrielle G. Long, David R. Black
Some recently-developed experimental techniques, such as in situ ultra-small-angle X-ray scattering (USAXS), have demonstrated a capability for measuring aspects of dislocation structure evolution that are inaccessible to other experimental methods

Development of the Atomic and Molecular Data Markup Language for Internet Data Exchange

October 16, 2008
Author(s)
Y Ralchenko, R Clark, D Humbert, David R. Schultz, T Kato, Y J. Rhee
Accelerated development of the Internet technologies, including those relevant to the atomic and molecular physics, poses new requirements for the proper communication between computers, users and applications. To this end, a new standard for atomic and

Does the Angle of a Fingerprint Scanner Affect User Performance?

September 22, 2008
Author(s)
Mary F. Theofanos, Ross J. Micheals, Shahram Orandi, Brian C. Stanton, Nien F. Zhang, Charles L. Sheppard
As the deployment of biometric technologies such as fingerprints has become more widespread in government applications there is an increased awareness of the human-computer interaction that such technologies involve. User behavior can impact operational

Usability Testing of Height and Angles of Ten-Print Fingerprint Capture

May 11, 2008
Author(s)
Mary F. Theofanos, Brian C. Stanton, Charles L. Sheppard, Ross J. Micheals, John W. Wydler II, Nien F. Zhang, Lawrence Nadel, William Rubin
As the deployment of biometric technologies such as fingerprints has become more widespread in government applications there is an increased awareness of the human-computer interaction that such technologies involve. User behavior can impact operational

Measurement of Weak Signals Using a Communications Receiver System

March 1, 2005
Author(s)
Marc Rutschlin, Kate Remley, Robert T. Johnk, Dylan Williams, Galen H. Koepke
We describe the calibration of an inexpensive, reliable system for use in weak-signal detection. The calibration procedure described allows the conversion of signals measured with the communications receiver system-which is based on a standard

On Higher Order Corrections for Propagating Uncertainties

January 1, 2005
Author(s)
Chih-Ming Wang, Hariharan K. Iyer
The ISO Guide to the Expression of Uncertainty in Measurement (GUM) recommends the use of a first-order Taylor series expansion for propagating errors and uncertainties. The GUM also suggests the use of a second-order Taylor series approximation for

A digitally programmable capacitance standard

April 1, 2004
Author(s)
Yicheng Wang, Lai H. Lee
We constructed a digitally programmable capacitance standard by modifying a commercial temperature-stabilized 100 pF capacitance standard which consists of 23 binary-weighted capacitor elements on a single fused-silica disk. The variable capacitor can be

Molecular Dynamics Study of the Solubility of Oxygen in Liquid Pyridine

December 1, 2003
Author(s)
Raymond D. Mountain
The solubility of oxygen in liquid pyridine is estimated using molecular dynamics to evaluate the chemical potential of the gas molecule in the liquid. The Kirkwood charging method is used with empirical potentials that generate reliable equations of state

Joint Distribution of Link Distances

March 1, 2003
Author(s)
Leonard E. Miller
The calculation of two-hop connectivity between two terminals for randomly deployed wireless networks requires the joint probability distribution of the distances between these terminals and the terminal that is acting as a relay. In general the distances

Continuously Tunable Precise, Single Frequency Optical Signal Generator

June 1, 2002
Author(s)
J D. Jost, John L. Hall, Jun Ye
To realize a genuine CW optical frequency synthesizer, a continuously tunable single-frequency CW laser has been employed to track preciselyany arbitrary component of a wide bandwidth phase-stabilized optical comb. We dermnstrate in experiment two

Core-Hole-Electron Interaction in X-Ray Raman Scattering

September 1, 2001
Author(s)
J A. Soininen, K Hamalainen, W A. Caliebe, C C. Kao, Eric L. Shirley
This work applies a recently developed first-principles scheme for calculating core-excited states in solids tonon-resonant inelastic x-ray scattering. Within the computational scheme the interaction between the excited electron and the core hole is

Structural Ceramics Database (Version June 2001)

June 1, 2001
Author(s)
R G. Munro
An update of the NIST Standard Reference Database Number 30, the Structural Ceramics Database, has been completed. This update, designated here as Version June 2001, increases the number of reference citations from 431 to 731, and increases the number of

The Relegation Algorithm

March 3, 2001
Author(s)
A Deprit, E Deprit, Jesuus Palacian
Given a perturbed Hamiltonian system, normalization yields a Lie transformation which converts the main part of the Hamiltonian into an integral of the transformed system. An extension of the normalization method--the relegation algorithm--does the same

A Phase-Field Model for Highly Anisotropic Interfacial Energy

March 1, 2001
Author(s)
J J. Eggleston, Geoffrey B. McFadden, P W. Voorhees
A computationally efficient phase-field model is developed for two-phase systems with anisotropic interfacial energy. The approach allows for anisotropies sufficiently high that the interface has corners or missing crystallographic orientations. The method

A Phase-Field Model for High Anisotropic InterfaciEnergy

January 1, 2001
Author(s)
Geoffrey B. McFadden, J J. Eggleston, P W. Voorhees
A computationally efficient phase-field model is developed for two-phase systems with anisotropic interfacial energy. The approach allows for anisotropies sufficiently high that the interface has corners or missing crystallographic orientations. The method

Automated Tracking of Structural Steel Members at the Construction Site

September 18, 2000
Author(s)
K M. Furlani, L E. Pfeffer
This paper presents further development and experimental testing of Comp-TRAK, a prototype system for identification and spatial tracking of structural steel components on a live construction site. Comp-TRAK is a web-based system for rapid tracking of
Displaying 7301 - 7325 of 9858
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