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Displaying 27201 - 27225 of 73830

Quantifying How Lighting and Focus Affect Face Recognition Performance

February 16, 2010
Author(s)
P J. Phillips, J. R. Beveridge, Bruce A. Draper, David Bolme, Geof H. Givens, Yui M. Lui
Recent studies show that face recognition in uncontrolled images remains a challenging problem, although the reasons why are less clear. Changes in illumination are one possible explanation, although algorithms developed since the advent of the PIE and

Heralded, pure-state single-photon source based on a Potassium Titanyl Phosphate waveguide

February 15, 2010
Author(s)
Zachary H. Levine, Jingyun Fan, Jun Chen, Alexander E. Ling, Alan L. Migdall
WWe analyze the generation of single spatial mode, spectrally uncorrelated photon pairs via type II spontaneous parametric downconversion in a Potassium Titanyl Phosphate (KTP) waveguide using real experimental parameters. We show that this source can be

Steady-state and transient photoconductivity in c-axis GaN nanowires grown by nitrogen-plasma-assisted molecular beam epitaxy

February 12, 2010
Author(s)
Norman A. Sanford, Paul T. Blanchard, Kristine A. Bertness, Lorelle Mansfield, John B. Schlager, Aric W. Sanders, Alexana Roshko, Beau Burton, Steven George
Analysis of steady-state and transient photoconductivity measurements at room temperature performed on c-axis oriented GaN nanowires yielded estimates of free carrier concentration, drift, mobility, surface band bending, and surface capture coefficient for

Challenges in Continuum Modeling of Intergranular Fracture

February 11, 2010
Author(s)
Valerie R. Coffman, James P. Sethna
Intergranular fracture in polycrystals is often simulated by finite elements coupled to a cohesive-zone model for the interfaces, requiring cohesive laws for grain boundaries as a function of their geometry. We discuss three challenges in understanding

Concrete nanoscience and nanotechnology: Definitions and applications

February 10, 2010
Author(s)
Edward Garboczi
There are many improvements needed in concrete, especially for use in renewal and expansion of the world's infrastructure, e.g. increased durability, decreased brittleness and increased tensile strength, and use of non-traditional materials like fly ash

Interfacial reactions of Ba2YCu3O6+x with Coated Conductor Buffer Layer, LaMnO3

February 10, 2010
Author(s)
Winnie K. Wong-Ng, Guangyao Liu, Lawrence P. Cook, James A. Kaduk
Chemical interactions between the Ba2YCu3O6+x superconductor and the LaMnO3 buffer layers employed in coated conductors have been investigated experimentally by determining the phases formed in the Ba2YCu3O6+x - LaMnO3 system. The Ba2YCu3O6+x - LaMnO3 join

Rational synthesis and characterization of a new family of low thermal conductivity misfit layered compounds [(PbSe)0.99]m[(WSe2)]n

February 9, 2010
Author(s)
Ian M. Anderson, Michael D. Anderson, Qiyin Lin, Mary Smeller, Colby L. Heideman, Paul Zschack, Mikio Koyano, Robert Kykyneshi, Douglas A. Keszler, David C. Johnson
We describe here a general synthesis approach for the preparation of new families of misfit layer compounds and demonstrate its effectiveness through the preparation of the first 64 members of the [(PbSe)0.99]m(WSe2)n family of compounds, where m and n are

Utility Assessment in TRANSTAC: Using a set of complementary methods

February 8, 2010
Author(s)
Michelle P. Steves, Emile L. Morse
This paper describes the methods used during formative utility assessments for speech-to-speech, real-time translation systems intended for tactical use. The systems, while still prototypical, had hardware platforms that could be exercised indoors or

Magnetic Properties of Zr_(9)Ni_(11)Intermetallic Compound

February 7, 2010
Author(s)
Virgil Provenzano, Robert D. Shull, Richard M. Waterstrat, Lawrence H. Bennett, Edward Della Torre, H. Seyoum
We report on a very interesting magnetic behavior in the intermetallic compound Zr_(9)Ni_(11), namely, (i) spin-glass behavior and (ii) fluctuations in magnetization versus temperature curves. The magnetic properties are consistent with structural results

Measurement Bandwidth Extension Using Multisine Signals: Propagation of Error

February 6, 2010
Author(s)
Catherine A. Remley, Dominique Schreurs, M. Myslinski, Dylan F. Williams
We describe a post-processing technique that can extend the effective measurement bandwidth of narrowband vector receivers by phase aligning overlapping measurements. The method requires only knowledge of the desired phases of a periodic, multisine

Optimization of spin-valve parameters for magnetic bead trapping and manipulation

February 6, 2010
Author(s)
Wendy R. Altman, John M. Moreland, Stephen E. Russek, Victor M. Bright
Magneto-optic Kerr effect (MOKE) and magnetoresistance (MR) measurements were used to measure the switching characteristics of spin-valve (SV) arrays currently being developed to trap and release superparamagnetic beads within a fluid medium. The effect of

Comparison of Large-Signal-Network-Analyzer Calibrations

February 5, 2010
Author(s)
Dylan F. Williams, Catherine A. Remley, Joe Gering, Grand Aivazian
We develop a procedure and metrics for comparing large-signal-network-analyzer calibrations. The metrics we develop provide a bound on differences between measurements obtained from large-signal-network-analyzer calibrations, as well as more specific

Development of a Candidate Reference Measurement Procedure for the Determination of 25-hydroxyvitamin D3 and 25-hydroxyvitamin D2 in Human Serum Using Isotope-Dilution Liquid Chromatography/Tandem Mass Spectrometry

February 5, 2010
Author(s)
Susan S. Tai, Mary Bedner, Karen W. Phinney
Vitamin D exists in two major forms, vitamin D3 and vitamin D2. Vitamin D helps the body absorb calcium and promote optimal growth. Both forms of vitamin D are metabolized to 25-hydroxyvitamin D in the body, and the levels of 25-hydroxyvitamin D3 (25-(OH
Displaying 27201 - 27225 of 73830
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