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NIST Authors in Bold

Displaying 25801 - 25825 of 74179

Quantum information processing and metrology with trapped ions

January 25, 2011
Author(s)
David J. Wineland, Dietrich G. Leibfried
The use of trapped atomic ions in the field of quantum information processing is briefly reviewed. We summarize the basic mechanisms required for logic gates and the use of the gates in demonstrating simple algorithms. We discuss the potential of trapped

Advancing the materials science of concrete with supercomputers

January 24, 2011
Author(s)
Jeffrey W. Bullard, Edward Garboczi, William L. George, Nicos Martys, Steven G. Satterfield, Judith E. Terrill
Supercomputers are renowned for being used on grand challenge problems like global weather patterns, nuclear device virtual testing, galaxy formation, unraveling molecular structure - and now concrete! Why do the mysteries of concrete form this kind of a

Making optical atomic clocks more stable with 10 -16 level laser stabilization

January 23, 2011
Author(s)
Andrew D. Ludlow, Yanyi Jiang, Nathan D. Lemke, Richard W. Fox, Jeffrey A. Sherman, Long-Sheng Ma, Christopher W. Oates
The superb precision of an atomic clock is derived from its stability. Atomic clocks based on optical (rather than microwave) frequencies are attractive because of their potential for high stability, which scales with operational frequency. Nevertheless

Bilateral NIST-PTB Comparison of Spectral Responsivity in the VUV

January 20, 2011
Author(s)
Uwe Arp, Ping-Shine Shaw, Zhigang Li, Alexander Gottwald, Mathias Richter
To compare the calibration capabilities for the spectral responsivity in the vacuum-ultraviolet spectral region between 135 nm and 250 nm, PTB and NIST agreed on a bilateral comparison. Calibrations of semiconductor photodiodes as transfer detectors were

Empirical Evidence for Increased False Reject Rate with Time Lapse in ICE 2006

January 20, 2011
Author(s)
P J. Phillips, Kevin W. Bowyer, Patrick J. Flynn, Sarah E. Baker
We present results of the first systematic study to investigate the degree to which template aging occurs for iris biometrics. Our experiments use an image data set with approximately four years of elapsed time between the earliest and most recent images

Measurements and Models for the Wireless Channel in a Ground-Based Urban Setting in Two Public Safety Frequency Bands

January 20, 2011
Author(s)
William F. Young, Catherine A. Remley, David W. Matolak, Qian Zhang, Christopher L. Holloway, Chriss A. Grosvenor, Camillo A. Gentile, Galen H. Koepke, Qiong Wu
We report on measured peer-to-peer (ground-based) wireless channel characteristics for an urban environment in two public safety frequency bands. Results are based upon measurements taken in Denver in June 2009. The public safety bands we investigated are

Robust Iris Recognition Baseline for the Occular Challenge

January 20, 2011
Author(s)
Yooyoung Lee, Ross J. Micheals, James J. Filliben, P J. Phillips
Due to its distinctiveness, the human iris is a popular biometric feature used to identity a person with high accuracy. The Grand Challenge in iris recognition is to have an effective algorithm for subject verification or identification under a broad range

Tranmission Electron Microscopy with a Liquid Flow Cell

January 20, 2011
Author(s)
Kate L. Klein, Ian M. Anderson, N. de Jonge
The imaging of microscopic structures at nanometer-scale spatial resolution in a liquid environment is of interest for a wide range of studies. Transmission electron microscopy (TEM) provides a method for imaging with the requisite spatial resolution, but

A Prototype of Modeling and Simulation for Sustainable Machining

January 19, 2011
Author(s)
Guodong Shao, Eric Chernow, Deogratias Kibira, Kevin W. Lyons
Modeling and simulation techniques have frequently been utilized to analyze manufacturing processes. The simulation of Numerically Controlled (NC) machine tools is preferred to real machine testing of the programs due to the potential savings of time and

Diffraction study of the retained austenite content in TRIP steels

January 19, 2011
Author(s)
Thomas H. Gnaupel-Herold, Adam Abel Creuziger
The results of a study of using neutron diffraction for determining the retained austenite content of TRIP steels are presented. The study covers a wide area of materials, deformation modes (uniaxial, biaxial and plane strain), strains, and the retained

NMR Characterization of the Formation Kinetics and Structure of Di-O-Benzylidene Sorbitol Gels Self-Assembled in Organic Solvents

January 19, 2011
Author(s)
David L. VanderHart, Jack F. Douglas, Steven Hudson, Joseph M. Antonucci, Elizabeth A. Wilder
The molecule 1,3:2,4-Di-O-Benzylidene sorbitol (DBS) is a common gelator that forms thermally reversible gels in diverse organic solvents. Solid state 13C and proton NMR techniques, along with electron microscopy, are utilized in an exploratory study of

Towards a Methodology for Analyzing Sustainability Standards using the Zachman Framework

January 19, 2011
Author(s)
Sudarsan Rachuri, Prabir Sarkar, Anantha Narayanan Narayanan, Jae H. Lee, Paul Witherell
There exists a multitude of standards and regulations related to sustainability. It is critical to enable users to identify applicable standards across entire lifecycles of products, processes, and services. To synthesize this variety of standards, it is

Controlled in situ Nanocavitation in Polymeric Materials

January 18, 2011
Author(s)
Yajun Cheng, Joseph M. Antonucci, Steven Hudson, Nancy Lin, Xinran Zhang, Sheng Lin-Gibson
A new strategy to produce polymer-inorganic composites with ultra low volume shrinkage has been developed. Small amount of cavitation agent, acetone dicarboxylic acid (ADCA), was introduced into acrylate-glass composites and decomposed in situ to carbon
Displaying 25801 - 25825 of 74179
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