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Search Publications

NIST Authors in Bold

Displaying 18601 - 18625 of 74205

Acoustic Techniques for Measuring Transport Properties of Gases

May 22, 2014
Author(s)
Keith A. Gillis, Michael R. Moldover
We describe the principles, techniques, and performance of acoustic resonators used to measure the shear viscosity, the thermal conductivity, and the bulk viscosity in gases. We developed the Greenspan acoustic viscometer at NIST, where colleagues used it

Collapse of the Cross-spectral Function

May 22, 2014
Author(s)
Craig W. Nelson, Archita Hati, David A. Howe
Cross-spectral analysis is a mathematical tool for extracting the power spectral density of a correlated signal from two time series in the presence of uncorrelated interfering signals. We demonstrate and explain a set of amplitude and phase conditions

Correlation Measurements between PM and AM Noise in Oscillators

May 22, 2014
Author(s)
Archita Hati, Craig W. Nelson, David A. Howe
We discuss techniques for measuring the correlation between phase modulated (PM) and amplitude modulated (AM) noise in an oscillator and report results of such correlation in a few selected oscillators of similar size, weight, power consumption and

Frequency Biases in a Cold-Atom Coherent Population Trapping Clock

May 22, 2014
Author(s)
Elizabeth A. Donley, Eric M. Blanshan, Francois-Xavier R. Esnault, John E. Kitching
A compact cold-atom clock based on coherent population trapping (CPT) has been developed. The clock typically demonstrates a short-term fractional frequency stability of 4x10 -11/√τ limited by frequency noise on the interrogation lasers. The largest two

Polar codes in a QKD Environment

May 22, 2014
Author(s)
Anastase Nakassis, Alan Mink
Polar coding is the most recent encoding scheme in the quest for error correction codes that approaches the Shannon limit, has a simple structure, and admits fast decoders. As such, it is an interesting candidate for the quantum key distribution (QKD)

A Binomial Approximation Method for the Ising Model

May 21, 2014
Author(s)
Isabel M. Beichl, Amanda A. Streib, Noah S. Streib, Francis Sullivan
A large portion of the complexity inherent to the Ising model can be captures with a trivial amount of computation. in this work, we support this claim by defining an approximation to the partition function and other thermodynamic quantities of the Ising

Advanced designs for non-imaging submillimeter-wave Winston cone concentrators

May 21, 2014
Author(s)
Andrew O. Nelson, Erich N. Grossman
We describe the design and simulation of several non-imaging concentrators designed to couple submillimeter wavelength radiation from free space into highly overmoded, rectangular, WR-10 waveguide. Previous designs are altered to improve the uniformity of

Identifying Face Quality and Factor Measures for Video

May 20, 2014
Author(s)
Yooyoung Lee, P. Jonathon Phillips, James Filliben, J. R. Beveridge, Hao Zhang
This paper identifies important factors for face recognition algorithm performance in video. The goal of this study is to understand key factors that affect algorithm performance and to characterize the algorithm performance. We evaluate four factor

Maturity Model Concepts for Sustainable Manufacturing

May 21, 2014
Author(s)
Sudarsan Rachuri, Sanjay Jain
The general awareness of the need for use of earth’s resources in a sustainable manner has been increasing in recent years. Governments, commercial organizations and individuals have been making efforts to better manage and use available resources

Traceability for Millimeter and Submillimeter-Wave Power Measurements

May 21, 2014
Author(s)
Ronald A. Ginley
The need for traceable power measurements above 110 GHz is well established for use in communications, spectral line investigation, molecular particle signature identification, material property characterization and others. There have been incremental

Flame Inhibition by CF3CHCl2 (HCFC-123)

May 20, 2014
Author(s)
Valeri I. Babushok, Gregory T. Linteris, Oliver Meier, John Pagliaro
A kinetic model is suggested for hydrocarbon-air flame propagation with addition of hydrochloroflurocarbon (HCFC) fire suppressants, encompassing the combined chemistry of fluorine- and chlorine-containing species. Calculated burning velocities using the

Optical hyperpolarization and NMR detection of 129 Xe on a microfluidic chip

May 20, 2014
Author(s)
Ricardo Jimenez Martinez, Daniel J. Kennedy, Michael Rosenbluh, Elizabeth A. Donley, Svenja A. Knappe, Scott J. Seltzer, Hattie L. Ring, Vikram S. Bajaj, John E. Kitching
We present a microfluidic chip that enables the production of laser-polarized 129Xe gas and its optical detection. Production of polarized 129Xe and its remote detection is achieved under flowing gas conditions at low magnetic fields in two separate

Stochastic Modeling and Simulation of Marginally Trapped Neutrons

May 20, 2014
Author(s)
Kevin J. Coakley
For a magnetic trapping experiment, I present an efficient method for simulating experimental beta −decay rates which accounts for loss of marginally trapped neutrons due to wall collisions and other possible loss mechanisms. Monte Carlo estimates of time
Displaying 18601 - 18625 of 74205