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Displaying 21151 - 21175 of 73830

Uncertainty Machine --- User's Manual

July 10, 2013
Author(s)
Antonio M. Possolo, Thomas V. Lafarge
NIST's Uncertainty Machine is a software application to evaluate the measurement uncertainty associated with an output quantity defined by a measurement model of the form y = f(x[1],...,x[n]), where the real-valued function f is specified fully and

A method for the analysis of behavioural uncertainty in evacuation modelling

July 9, 2013
Author(s)
Enrico Ronchi, Paul A. Reneke, Richard D. Peacock
Evacuation models generally include the use of distributions or probabilistic variables to simulate the variability of possible human behaviours. A single model setup of the same evacuation scenario may therefore produce a distribution of different

Broadband S-parameter characterization of a DC-SQUID amplifier

July 9, 2013
Author(s)
Leonardo M. Ranzani, Lafe F. Spietz, Jose A. Aumentado
In this work we characterize the 2-port scattering parameters of a superconducting quantum interference device (DC-SQUID) ampli er at 20 mK in the 2{8 GHz band. The measurement reference plane is positioned on a 6.25 microstrip line situated directly at

Economic Case Study: The Impact of NSTIC on the Internal Revenue Service

July 9, 2013
Author(s)
Gregory C. Tassey
The National Strategy for Trusted Identities in Cyberspace (NSTIC) offers a vision of more secure, efficient, and cost-effective authentication through widespread use of robust third-party credentials standardized to a national strategy. If successful

Spinor Dynamics in an Antiferromagnetic spin-1 Thermal Bose Gas

July 9, 2013
Author(s)
Hyewon K. Pechkis, Jonathan Wrubel, Arne Schwettmann, Paul Griffin, Ryan Barnett, Eite Tiesinga, Paul D. Lett
We present experimental observations of coherent spin-population oscillations in a cold thermal, Bose gas of spin-1 23Na atoms. The population oscillations in a multi-spatial-mode thermal gas have the same behavior as those observed in a single-spatial

Mechanical Control of a Microrod-Resonator Optical Frequency Comb

July 8, 2013
Author(s)
Scott B. Papp, Pascal P. Del'Haye, Scott A. Diddams
Robust control and stabilization of optical frequency combs enables an extraordinary range of scientific and technological applications, including frequency metrology at extreme levels of precision, novel spectroscopy of quantum gases and of molecules from

Properties of magnetic barrier structures for superconducting-magnetic hybrid Josephson junctions

July 7, 2013
Author(s)
Burm Baek, Samuel P. Benz, William H. Rippard, Stephen E. Russek, Paul D. Dresselhaus, Horst Rogalla, Matthew R. Pufall
If Josephson and spintronic technologies can be successfully integrated to produce a cryogenic memory that can be controlled with single-flux quantum pulses, then they may enable ultra-low-power, high-speed computing. We have developed hybrid Josephson

Sensitivity of Probes in Near-Field Spherical-Scanning Antenna Measurements

July 7, 2013
Author(s)
Ronald C. Wittmann, Michael H. Francis
We define and calculate sensitivity for several actual and simulated probes. Probe sensitivity can have a significant impact on measurement uncertainty associated with probe deconvolution in near- field, spherical scanning, antenna measurements.

A highly ordered non-crystalline metallic phase

July 5, 2013
Author(s)
Gabrielle G. Long, Karena Chapman, Peter Chupas, Leonid A. Bendersky, Lyle E. Levine, Frederic Mompiou, John W. Cahn, Judith K. Stalick
We report the characterization of an ordered non-crystalline isotropic metallic solid that, during rapid cooling of an Al-Fe-Si melt, forms by nucleation, followed by growth along a moving interface between the solid and melt with partitioning of the

LaTeXML 2012 -- A Year of LaTeXML

July 5, 2013
Author(s)
Deyan Ginev, Bruce R. Miller
LaTeXML, a TeX to XML converter, is being used in a wide range of MKM applications. In this paper, we present a progress report for the 2012 calendar year. Noteworthy enhancements include: increased coverage such as Wikipedia syntax; enhanced capabilities

Metrological Challenges Introduced by New Tolerancing Standards

July 5, 2013
Author(s)
Ed Morse, Yue Peng, Vijay Srinivasan, Craig M. Shakarji
The recent release of ISO 14405-1 has provided designers with a richer set of specification tools for the size of part features, so that various functional requirements can be captured with greater fidelity. However, these tools also bring new challenges

Direct Observation of Zitterbewegung in a Bose-Einstein condensate

July 3, 2013
Author(s)
Lindsay J. LeBlanc, Matthew Beeler, Karina Jimenez-Garcia, Abigail R. Perry, Seiji Sugawa, Ross Williams, Ian B. Spielman
Zitterbewegung, a force-free trembling motion first predicted for relativistic fermions like electrons, was an unexpected consequence of the Dirac equation's unification of quantum mechanics and special relativity. Though the oscillatory motion's large

Measurements of effective diffusion coefficients of helium and hydrogen through gypsum

July 3, 2013
Author(s)
Jiann C. Yang, William M. Pitts, Marco G. Fernandez, Kuldeep R. Prasad
An experimental apparatus, which was based on the ¿-scale garage previously used for studying helium release and dispersion in our laboratory, was used to obtain effective diffusion coefficients of helium and hydrogen (released as forming gas for safety

Strong equivalence of reversible circuits is coNP-complete

July 2, 2013
Author(s)
Stephen P. Jordan
It is well-known that deciding equivalence of logic circuits is a coNP-complete problem. As a corollary, the problem of deciding weak equivalence of reversible circuits, i.e. ignoring the ancilla bits, is also coNP-complete. The complexity of deciding

A Prescription for Sub-Millimeter-Wave Transistor Characterization

July 1, 2013
Author(s)
Dylan F. Williams, Adam C. Young, Urteaga Miguel
We present an approach for characterizing transistors embedded in microstrip lines formed on a thin bisbenzocyclobutene-based (BCB) monomers film at sub-millimeter-wave frequencies. We demonstrate the approach to 750 GHz and estimate the uncertainty of the

Calibration-Kit Design for Millimeter-Wave Silicon Integrated Circuits

July 1, 2013
Author(s)
Dylan F. Williams, Phillip Corson, Sharma Jahnavi, Krishnaswamy Harish, Tai Wei, George Zacharias, Ricketts David, Watson Paul, Dacquay Eric, Voinigescu Sorin
We study and present design guidelines for thru-reflect-line vector-network-analyzer calibration kits used for characterizing circuits and transistors fabricated on silicon integrated circuits at millimeter-wave frequencies. We compare contact-pad designs

Capturing Rare Cells From Blood Using a Packed Bed of Custom-Synthesized Chitosan Microparticles

July 1, 2013
Author(s)
Chandamany Arya, Jason Kralj, Kunqiang Jiang, Matt S. Munson, Thomas Forbes, Don L. DeVoe, Srinivasa R. Raghavan, Samuel Forry
Uniform multifunctional chitosan microparticles were produced in large numbers using a simple and inexpensive microtubing arrangement. The particles were functionalized through both physical encapsulation of carbon black, to attenuate autofluorescence, and

Conditions for two-photon interference with coherent pulses

July 1, 2013
Author(s)
Yong-Su Kim, Oliver T. Slattery, Paulina Kuo, Xiao Tang
We report experiments on two-photon interference between temporally non-overlapping weak coherent pulses. While the single-photon interference is washed out, the two-photon interference shows a Hong-Ou-Mandel dip with visibility of 0.50±0.09, which shows
Displaying 21151 - 21175 of 73830
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