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Displaying 26751 - 26775 of 73970

INTERCOMPARISON OF W-BAND STANDARD GAIN HORN ANTENNAS

June 13, 2010
Author(s)
Katherine MacReynolds, J. Kang, N. Kang, D. Gentle, Michael H. Francis
An intercomparison of power gain for W-band (75 GHz to 110 GHz) standard horn antennas has been performed among KRISS, NPL and NIST. This paper describes the comparison and its measurement results.

Microwave Optimization of 10 V PJVS Circuits

June 13, 2010
Author(s)
Paul D. Dresselhaus, Mike Elsbury, Charles J. Burroughs, Samuel P. Benz
Proper operation of programmable Josephson voltage standard arrays depends on the uniform distribution of microwaves to a large number of Josephson junctions. Too much or too little microwave power will change the current range of a junction s constant

Power Spectral Density: Is it right?

June 13, 2010
Author(s)
Ulf Griesmann, John Lehan, Jiyoung Chu
We concentrate on the instrumental issues surrounding power spectral density (PSD) determination, using as an example, the most common optical shop QA tool, the Fizeau interferometer. We briefly discuss the properties of an ideal calibration method for PSD

Quantifying How Lighting and Focus Affect Face Recognition Performance

June 13, 2010
Author(s)
J. R. Beveridge, David Bolme, Bruce A. Draper, Geof H. Givens, Yui M. Lui, P. Jonathon Phillips
Recent studies show that face recognition in uncontrolled images remains a challenging problem, although the reasons why are less clear. Changes in illumination are one possible explanation, although algorithms developed since the advent of the PIE and

Reduced Nonlinearities in the NIST Johnson Noise Thermometry System

June 13, 2010
Author(s)
Jifeng Qu, Samuel Benz, Alessio Pollarolo, Horst Rogalla
Improved electronics and synthesized noise waveforms for the NIST quantum-voltage-standard- calibrated Johnson noise thermometer (JNT) have lead to reduced uncertainty in the temperature measurement. Recent measurements show that some of the distortion in

Development and Demonstration of a Method to Evaluate Bio-Sampling Strategies Using Building Simulation and Sample Planning Software

June 10, 2010
Author(s)
William S. Dols, Jayne B. Morrow, Andrew K. Persily, Brett Matzke, Landon Sego, Lisa Nuffer, Brent Pulsipher
response and recovery sampling approaches and technologies, the U.S. Department of Homeland Security (DHS), along with several other agencies, have simulated a biothreat agent release within a facility at Idaho National Laboratory (INL) on two separate

Effects of fiber gripping methods on single fiber tensile test using Kolsky bar

June 10, 2010
Author(s)
Jae Hyun Kim, Richard L. Rhorer, Haruki Kobayashi, Walter G. McDonough, Gale A. Holmes
Preliminary data by Ming Cheng et al. indicate minimal impact of strain rate on the tensile stress-strain behavior of Kevlar. However, technical issues associated with specimen preparation appear to limit the number of samples and show an undesirable

From the bottom up measuring bulk mechanical properties via microtechnology

June 10, 2010
Author(s)
Nicholas Barbosa, Sudook A. Kim, David T. Read
The micromechanics community has developed a large set of tools for measuring the properties of micro- and nano-scaled materials. These new tools have been successfully applied to a range of materials, most often in thin-film form, to determine the

Occupant Behavior in a High-rise Office Building Fire

June 10, 2010
Author(s)
Erica D. Kuligowski, Bryan L. Hoskins
Survey responses from occupants involved in a 32-story high-rise building evacuation during an actual fire were collected and analyzed to study the pre-evacuation period. Multiple regression models were used to test whether specific occupant, building, and

Rationale of Color Quality Scale

June 10, 2010
Author(s)
Yoshihiro Ohno, Wendy L. Davis
The color quality of solid state lighting (SSL) products is critical and is the subject of increasing attention. The CIE Color Rendering Index (CRI) [1] has been widely used for many years. However, the CRI is 35 years old and various problems of the CRI

State of Security Readiness

June 10, 2010
Author(s)
Ramaswamy Chandramouli, Peter M. Mell
Cloud computing is a model for enabling convenient, on-demand network access to a shared pool of configurable computing resources that can be rapidly provisioned and released with minimal management effort or service provider interaction. However, the

Accurate light-time correction due to a gravitating mass

June 7, 2010
Author(s)
Neil Ashby, Bruno Bertotti
This technical paper of mathematical physics arose as an aftermath of the 2002 Cassini experiment, in which the PPN parameter γ was measured with an accuracy ς γ = 2.3 × 10 -5 and found consistent with the rediction γ=1 of general relativity. The Orbit

Dark pulse quantum dot diode laser

June 7, 2010
Author(s)
Mingming M. Feng, Kevin L. Silverman, Richard P. Mirin, Steven T. Cundiff
We describe an operating regime for passively mode-locked quantum dot diode laser where the output consists of a train of dark pulses, i.e., intensity dips on a continuous background. We show that a dark pulse train is a solution to the master equation for

Dynamic Deformation of Jacketed Lead Bullets Captured By High Speed DIC

June 7, 2010
Author(s)
Steven P. Mates
The development of high fidelity simulations of lead-cored bullet impacts on soft body armor, motivated by the need for improved armor designs and performance standards for law enforcement, requires accurate models for both the armor and the deformable
Displaying 26751 - 26775 of 73970
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