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Search Publications

NIST Authors in Bold

Displaying 27351 - 27375 of 74220

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

Combinatorial Software Testing

August 7, 2009
Author(s)
David R. Kuhn, Raghu N. Kacker, Yu Lei, Justin Hunter
Developers of large data-intensive software often notice an interesting - though not surprising - phenomenon: when usage of an application jumps dramatically, components that have operated for months without trouble suddenly develop previously undetected

Development of a Seebeck Coefficient Standard Reference Material

August 7, 2009
Author(s)
Nathan Lowhorn, Winnie Wong-Ng, John Lu, Evan L. Thomas, Makoto Otani, Martin L. Green, Neil Dilley, Jeffrey Sharp, Thanh N. Tran
We have successfully developed a Seebeck coefficient Standard Reference Material (SRM ), Bi2Te3, that is crucial for interlaboratory data comparison and for instrument calibration. Certification measurements were performed using two different techniques on

Measurements to Support Public Safety Communications: Attenuation and Variability of 750 MHz Radio Wave Signals in Four Large Building Structures: NIST Technical Note 1552

August 7, 2009
Author(s)
William F. Young, Kate Remley, John M. Ladbury, Christopher L. Holloway, Chriss A. Grosvenor, Galen H. Koepke, Sander Floris, Wouter Numan, Andrea Garuti
In this report, we investigate radio communication problems faced by emergency responders (firefighters, police, and emergency medical personnel) in disaster situations. A fundamental challenge to radio communications into and out of large buildings is the

Volatility of Aprotic Ionic Liquids - A Review

August 7, 2009
Author(s)
Jose M.S.S. Esperanca, Jose N. Canongia Lopes, Mohd Tariq, Luis M.N.B.F. Santos, Joe W. Magee, Luis P. Rebelo
A review of research on the volatility of aprotic ionic liquids is presented. This topic is limited to aprotic liquids, since measurements have led to a generalization that this class of substances possesses an extremely low vapor pressure. For research

Optimizing Authentication in Media Independent Handovers using IEEE 802.21

August 6, 2009
Author(s)
Antonio Izquierdo Manzanares, Nada T. Golmie, Richard A. Rouil
In this paper we study the performance of the authentication process in media independent handovers, and consider the impact of using IEEE 802.21 link triggers to achieve seamless mobility. We describe all interactions between the 802.21 services and the

Protein crystal engineering of YpAC-IV using a strategy of excess charge reduction

August 5, 2009
Author(s)
David T. Gallagher, N N. Smith, Sung Kim, Howard Robinson, Prasad T. Reddy
The class IV adenylyl cyclase from Yersinia pestis has been engineered to enable crystallization at neutral pH for mechanism studies. The wild-type enzyme crystallized only at pH below 5. Based on the unliganded wild-type structure 2FJT at 1.9 Angstrom

The Fifth Industrial Fluid Properties Simulation Challenge

August 5, 2009
Author(s)
F Case, Anne M. Chaka, J Moore, Raymond D. Mountain, J Olson, Richard B. Ross, Martin Schiller, Vincent K. Shen, Eric A. Stahlberg
The fifth industrial fluid properties simulation challenge was held in 2008. In it the contestants were challenged to predict specific, industrially relevant, properties of fluid systems, namely the 1-octanol /water partition coefficient and the infinite

Cell Interactions with Biomaterials Gradients and Arrays

August 4, 2009
Author(s)
Yanyin Yang, Vinoy Thomas, Abby W. Morgan, Shauna M. Dorsey, Carl Simon Jr.
Gradients and arrays have become very useful to the fields of tissue engineering and biomaterials.  Both gradients and arrays make efficient platforms for screening cell response to biomaterials.  Graded biomaterials also have functional applications and
Displaying 27351 - 27375 of 74220