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NIST Authors in Bold

Displaying 28101 - 28125 of 73829

Coalescing GSICS Correction Coefficients

August 14, 2009
Author(s)
Ruediger Kessel
We would like to present a technique to adjust the uncertainty estimates of each point in a time series, so that the variance of the time series is consistent with the uncertainty estimates of its component points. This would allow the uncertainty of the

Dynamic Gravitational Standard for Liquid Flow: Model and Measurements

August 14, 2009
Author(s)
Iosif I. Shinder, Michael R. Moldover
We report progress in testing a dynamic gravimetric standard using both steady and unsteady water flows. For steady flows in the range 10 kg/s to 60 kg/s, the difference between the dynamic standard and NIST s static primary standard was 0.015 % with a

The Calculation of Natural Gas Viscosity

August 14, 2009
Author(s)
Aaron N. Johnson, William Johansen
The calculation of natural gas viscosity has been implemented many different ways including the use of constants. Different methods of calculating natural gas viscosity may produce values with differences as large as 50%. Increasing natural gas prices

Use of ISO/IEC 24727

August 14, 2009
Author(s)
Hildegard Ferraiolo, Teresa T. Schwarzhoff, William I. MacGregor, Hung Dang, Ketan Mehta
This document describes the use of ISO/IEC 24727 in enabling client-applications to access identity credentials issued by different credential issuers.

ENABLING STANDARDS FOR NANOMATERIAL CHARACTERIZATION

August 13, 2009
Author(s)
Vincent A. Hackley, Martin Fritts, James F. Kelly, Anil K. Patri, Alan F. Rawle
A two-day international workshop was convened recently in order to scope out and address the urgent need for standards to accurately characterize the physico-chemical and biological properties of engineered nanomaterials. These standards are needed by

Recommended Practices for Homeland Security Modeling and Simulation

August 13, 2009
Author(s)
Sanjay Jain, Charles McLean
This paper recommends practices for development and deployment of modeling, simulation and analysis (MS&A) tools for homeland security applications. The set of recommended practices applicable to any MS&A application includes: software engineering practice

Performance of a Nanopositioner Controller Filter Compensator

August 12, 2009
Author(s)
Donna Le, Nicholas Dagalakis, Jason J. Gorman, Jae M. Yoo
We describe the use of appropriate type simple resistor and capacitor (RC) compensators, which properly connected to a power amplifier, can improve the dynamic performance of MEMS nanopositioners. Research on compensators led to the design of several

Security and Privacy Issues in Agent-Based Location-Aware Mobile Commerce

August 12, 2009
Author(s)
Tom T. Karygiannis, Emmanouil Antonakakis
Mobile commerce and location-aware services promise to combine the conveniences of both online and offline bricks-and-mortar services. Just as agent-enabled desktop computers can be used to improve a users e-commerce experience, so can agent-enabled mobile

Visualization of Structural Behavior under Fire

August 12, 2009
Author(s)
Dilip K. Banerjee, William J. Hess, Thomas M. Olano, Judith E. Terrill, John L. Gross
An integrated environment was created to study the interaction among fire, heat transfer, and structural deformation from a typical room fire. The fire, thermal, and structural data were linked with a separate 3-D visualization capability, to provide the

Design and Experimental Verification of a 3D Magnetic EZ Antenna at 300 MHz

August 11, 2009
Author(s)
Christopher L. Holloway, Richard Ziolkowski, Chia-Ching Lin, J. A. Nielsen, M. H. Tanielian
Several variations of a 300 MHz version of the electrically small coax-fed three-dimensional (3D) magnetic EZ antenna were designed and tested. The final design was achieved when the impact of the fabrication techniques on its parameters were understood

Diffusion Under Temperature Gradient: A Phase-field Model Study

August 11, 2009
Author(s)
Rashmi R. Mohanty, Jonathan E. Guyer, Yong Ho Sohn
A diffuse interface model was devised and employed to investigate the effect of thermotransport (a.k.a., thermomigration) process in single-phase and multi-phase alloys of a binary system. Simulation results show that an applied temperature gradient can

Factors that Influence Algorithm Performance

August 11, 2009
Author(s)
P J. Phillips, J. R. Beveridge, Geof H. Givens, Bruce A. Draper
A statistical study is presented quantifying the effects of covariates such as gender, age, expression, image resolution and focus on three face recognition algorithms. Specifically, a Generalized Linear Mixed Effect model is used to relate probability of

Formation of Silicon-Based Molecular Electronic Structures Using Flip-chip Lamination

August 11, 2009
Author(s)
Mariona Coll Bau, Lauren H. Miller, Lee J. Richter, Daniel R. Hines, Curt A. Richter, Christina A. Hacker
The use of organic molecules to impart electrical surface properties has been a subject of intense research not only from a fundamental perspective but for many technological applications. In particular, organic molecules have been proposed as active

Lattice Interferometer for Ultra-Cold Atoms

August 11, 2009
Author(s)
Mikkel Andersen, Tycho Sleator
We demonstrate an atomic interferometer based on ultra-cold atoms released from an optical lattice. This technique yields a large improvement in signal to noise over a related interferometer previously demonstrated. The interferometer involves diffraction

NIST s Integrated Colony Enumerator (NICE)

August 11, 2009
Author(s)
Matthew L. Clarke, Jeeseong Hwang
Enumeration of bacterial colonies in an agar plate is simple in concept, but automated colony counting is difficult due to variations in colony color, size, shape, contrast, and density, as well as colony overlap. Furthermore, in applications where high

A System Dynamics Modeling Framework for Sustainable Manufacturing

August 10, 2009
Author(s)
Deogratias Kibira, Sanjay Jain, Charles McLean
This paper proposes a framework for application of system dynamics modeling to sustainable manufacturing. Sustainable manufacturing involves interaction of multiple complex systems including those in manufacturing, environmental, financial, and social

Reference measurements of Hydrogen's Dielectric Permittivity

August 10, 2009
Author(s)
James W. Schmidt, Michael R. Moldover, Eric F. May
We used a quasi-spherical cavity resonator to measure the relative dielectric permittivity ε r of H 2 at frequencies from 2.4 GHz to 7.3 GHz, at pressures up to 6.5 MPa, and at the temperatures 273 K and 293 K. The resonator was calibrated using auxiliary

A Spin-1/2 Optical Lattice Clock

August 7, 2009
Author(s)
Nathan D. Lemke, Andrew D. Ludlow, Zeb Barber, Tara M. Fortier, Scott A. Diddams, Yanyi Jiang, Steven R. Jefferts, Thomas P. Heavner, Thomas E. Parker, Christopher W. Oates
We experimentally investigate an optical clock based on 171Yb (I = 1/2) atoms confined in an optical lattice. We have evaluated all known frequency shifts to the clock transition, including the density-dependent collision shift, with an uncertainty of 0.19
Displaying 28101 - 28125 of 73829
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