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NIST Authors in Bold

Displaying 29651 - 29675 of 74220

Recent atomic clock comparisions at NIST

October 1, 2008
Author(s)
Luca Lorini, Neil Ashby, Anders Brusch, Scott Diddams, Robert E. Drullinger, Eric Eason, Tara Fortier, Pat Hastings, Thomas P. Heavner, David Hume, Wayne M. Itano, Steven R. Jefferts, Nathan R. Newbury, Tom Parker, Till P. Rosenband, Jason Stalnaker, William C. Swann, David J. Wineland, James C. Bergquist
The record of atomic clock frequency comparisons at NIST over the past half-decade provides one of the tightest constraints of any present-day, temporal variations of the fundamental constants. Notably, the 6-year record of increasingly precise

Robustness of display hemispherical reflectance measurement apparatus

October 1, 2008
Author(s)
John Penczek, Edward F. Kelley, Seugkwan Kim
Reflection measurements are critical to the evaluation of display performance under ambient illumination conditions. Various hemispherical reflection methods are evaluated for their suitability and robustness across display technologies. The standard

Superfludity and phase transitions in a resonant Bose gas

October 1, 2008
Author(s)
Leo Radzihovsky, Peter B. Weichman, Jae Park
The atomic Bose gas is studied across a Feshbach resonance, mapping out its phase diagram, and computing its thermodynamics and excitation spectra. It is shown that such a degenerate gas admits two distinct atomic and molecular superfluid phases, with the

Using uncalibrated lasers as wavelength standards

October 1, 2008
Author(s)
Jack A. Stone Jr.
The fundamental atomic physics of a gas laser transition is such that the transition frequency, or equivalently, the vacuum wavelength of the laser, cannot vary from its central value by more than a few parts in 106. The uncertainty of the gas laser

Contaminant Accumulation and Removal in Building Plumbing Systems

September 30, 2008
Author(s)
Stephen J. Treado, Mark A. Kedzierski, Daniel R. Flynn, David Wilmering, Thomas D. Montgomery, Kenneth D. Cole
This report summarizes measurements and results conducted to evaluate the accumulation and removal of water-borne contaminants in building plumbing systems. In particular, tests were conducted at the BFRL Plumbing Test Facility, which emulates a full-scale

Investigations of a coherently driven semiconductor optical cavity QED system

September 30, 2008
Author(s)
Kartik A. Srinivasan, Christopher P. Michael, Raviv Perahia, Oskar Painter
Chip-based cavity QED devices consisting of a self-assembled InAs quantum dot (QD) coupled to a high quality factor GaAs microdisk cavity are coherently probed through the optical channel using a fiber taper waveguide. We highlight one particularly

Practical Challenges in Wireless Sensor Network Use in Buildings

September 30, 2008
Author(s)
William M. Healy, Won Suk Jang
While wireless sensor network technology has advanced in recent years, potential users of these systems in buildings still have concerns with their use. This report summarizes results of a literature survey and interactions with building industry

Technical Guide to Information Security Testing and Assessment

September 30, 2008
Author(s)
Murugiah P. Souppaya, Karen A. Scarfone
The purpose of this document is to assist organizations in planning and conducting technical information security tests and examinations, analyzing findings, and developing mitigation strategies. The guide provides practical recommendations for designing

The Nature of Deuterium Arrangements in YD3 and other Rare-Earth Trideuterides

September 30, 2008
Author(s)
Terrence J. Udovic, Qingzhen Huang, Antonio Santoro, John J. Rush
The efficacy of different structural models for describing the observed neutron-powder-diffraction (NPD) measurements of bulk polycrystalline YD3 as well as other hexagonal rare-earth (i.e., Nd, Tb, Dy, Ho, Er, and Tm) trideuteride powders has been

An Application Framework for IEEE 1588 Standard

September 29, 2008
Author(s)
Yuyin Song, Kang B. Lee
This paper introduces an application framework for the Institute of Electrical and Electronics Engineers (IEEE) 1588 standard. This application framework developed at the National Institute of Standards and Technology (NIST) consists of five layers

Effects of Specimen Geometry on Fatigue-Crack Growth Rates in Pipeline Steels

September 29, 2008
Author(s)
John M. Treinen, Philippe P. Darcis, Joseph D. McColskey, R. Smith, J. Merritt
In this study, the effect of specimen geometry on the fatigue crack growth rates (FCGR) in API X65 and X100 pipeline steels was explored using the middle tension and compact tension specimen geometries. It was found that the specimen type has little

The Iris Challenge Evaluation 2005

September 29, 2008
Author(s)
P J. Phillips, Kevin W. Bowyer, Patrick J. Flynn, Xiaomei Liu, W T. Scruggs
This paper describes the Iris Challenge Evaluation (ICE) 2005. The ICE 2005 contains a dataset of 2953 iris images from 132 subjects. The data is organized into two experiments: right and left eye. Iris recognition performance is presented for twelve
Displaying 29651 - 29675 of 74220