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Displaying 32126 - 32150 of 74084

DUC 2005: Evaluation of Question-Focused Summarization Systems

January 22, 2007
Author(s)
Hoa T. Dang
The Document Understanding Conference (DUC) 2005 evaluation had a single user-oriented, question-focused summarization task, which was to synthesize from a set of 25-50 documents a well-organized, fluent answer to a complex question. The evaluation shows

Dynamic Test Collections: Measuring Search Effectiveness on the Live Web

January 22, 2007
Author(s)
Ian M. Soboroff
Existing methods for measuring the quality of search algorithms use a static collection of documents. A set of queries and a mapping from the queries to the relevant documents allow the experimenter to see how well different search engines or engine

Influence of Oxygen Vacancies on the Dielectric Properties of Hafnia

January 22, 2007
Author(s)
Eric J. Cockayne
First-principles calculations were used to study the effects of neutral and 2+ charged oxygen vacancies on the dielectric properties of crystalline HfO2. In agreement with previous results, the neutral vacancy is more stable on the 4-fold coordinated site

Fluorescence Intermittency and Spectral Shifts of Single Bio-Conjugated Nanocrystals Studied by Single Molecule Confocal Fluorescence Microscopy and Spectroscopy

January 21, 2007
Author(s)
Hyeong G. Kang, Mathew Maye, Dmytro Nykypanchuk, Matthew L. Clarke, Peter Yim, J R. Krogmeier, Kimberly A. Briggman, Oleg Gang, Jeeseong Hwang
We have fabricated a combined measurement system capable of confocal microscopy and fluorescence spectroscopy to simultaneously evaluate multiple optical characteristics of single fluorescent nanocrystals. The single particle detection sensitivity is

Spherical Rubidium Vapor Cells Fabricated By Micro Glass Blowing

January 21, 2007
Author(s)
E. J. Eklund, A Shkel, Svenja A. Knappe, Elizabeth A. Donley, John E. Kitching
This paper presents an application of micro glass blowing, in which multiple glass spheres are simultaneously shaped on top of a silicon wafer and subsequently filled with rubidium. The fabrication process is based on etching cavities in silicon, followed

User's Guide to NIST Biometric Image Software (NBIS)

January 21, 2007
Author(s)
Kenneth Ko
This document (User's Guide to NIST Biometric Image Software (NBIS)) is renamed from the User's Guide to NIST Fingerprint Image Software (NFIS). In other word, this document is a replacement for the User's Guide to NIST Fingerprint Image software (NFIS)

Long-Term Stability of Chip-Scale Atomic Clock Physics Packages

January 20, 2007
Author(s)
Svenja A. Knappe, Vladislav Gerginov, V Shah, Alan Brannon, Hugh Robinson, Leo W. Hollberg, John E. Kitching
We present measurements regarding the long-term stability of chip-scale atomic clock (CSAC) physics packages. The tight requirements for the temperature stability of vapor cell and laser in these packages currently limit their frequency stability after 100

Characterization of cell samples from measurements of spectroscopic scattering phase dispersion

January 19, 2007
Author(s)
Shellee D. Dyer, Lara Roberson, Shelley M. Etzel, Tasshi Dennis, Andrew Dienstfrey, Vadim Tsvankin, Wei Tan
We present spectroscopic swept-source optical coherence tomography (OCT) measurements of the phase-dispersion of cell samples. We have previously demonstrated that the phase of the scattered field is, in general, independent of the intensity, and both must

Origins of switching field distributions in perpendicular magnetic nanodot arrays

January 19, 2007
Author(s)
Justin Shaw, William Rippard, Stephen E. Russek, Tim Reith, Charles M. Falco
We studied the reversal properties of perpendicularly magnetized Co/Pd nanodots from 100 to 50 nm in diameter fabricated using electron beam lithography. Polycrystalline Co/Pd multilayers show considerable differences in the switching field distribution

Phase Field Theory of Heterogeneous Crystal Nucleation

January 19, 2007
Author(s)
L Granasy, T Pusztai, D M. Saylor, James A. Warren
A phase field approach is developed to model wetting and heterogeneous crystal nucleation of an undercooled pure liquid in contact with a sharp wall. We discuss various choices for the boundary condition at the wall and determine the properties of critical

Radian-level coherent optical links over 100's of meters and 100's of terahertz

January 18, 2007
Author(s)
Ian R. Coddington, Qudsia Quraishi, Luca Lorini, William C. Swann, J. C. Bergquist, C. W. Oates, Scott Diddams, Nathan R. Newbury
We demonstrate coherent transfer of optical signals with radian level noise (in a 25 MHz bandwidth) through a series of laser systems spanning from 657 nm to 1550 nm over several hundred meter distances.

Charge Offset Stability in Tunable-Barrier Si SET Devices

January 17, 2007
Author(s)
Neil M. Zimmerman, Brian Simonds, Mikio Fujiwara, Yukinori Ono, Yasuo Takahashi, Hiroshi Inokawa
The problem of charge offset drift in single-electron tunneling devices, based on the Coulomb blockade, can preclude their useful application in metrology and integrated devices. We demonstrate that in tunable-barrier Si-based SET transistors there is

A Measurement of Propagation Delay

January 16, 2007
Author(s)
Donald R. Larson, Nicholas Paulter
A measurement method and associated uncertainty analysis have been developed for the measurement of propagation or group delay in electrical transmission lines and optical fibers. The measurement method and uncertainty analysis were applied to measurements

Analysis of C-S-H Gel and Cement Paste by Small-Angle Neutron Scattering

January 16, 2007
Author(s)
Andrew J. Allen, J Thomas
The role of small-angle x-ray and neutron scattering (SAXS and SANS) in the characterization of cement is briefly reviewed. The unique information obtainable from SANS analysis of C-S-H gel in hydrating cement is compared with that obtainable by other

Composition and Density of Amorphous Calcium-Silicate-Hydrate in Cement

January 16, 2007
Author(s)
Andrew J. Allen, J Thomas, Hamlin M. Jennings
Despite intensive research for over a century, the main binding reaction product of cement hydration, calcium-silicate-hydrate (C-S-H) gel, is not fully understood. By combining absolute-calibrated small-angle and ultrasmall-angle neutron and x-ray

Measuring Molecular Order in Poly(3-alkylthiophene) Thin Films with Polarizing Spectroscopies

January 16, 2007
Author(s)
Marc Gurau, Dean DeLongchamp, Brandon M. Vogel, Eric K. Lin, Daniel A. Fischer, S Sambasivan, Lee J. Richter
We measured the molecular order of poly(3-alkylthiophene) chains in thin films before and after melting through the combination of several polarized photon spectroscopies: infrared (IR) absorption, variable angle spectroscopic ellipsometry (SE), and near

Synthesis and Structural Characterization of Glucopyranosylamide Films on Gold

January 16, 2007
Author(s)
Mridula Kadalbajoo, J J. Park, A Opdahl, Hiromi Suda, Kitchens A. C, Jayne C. Garno, J Batteas, Michael J. Tarlov, Phillip DeShong
Stereoselective synthesis of a- and b-linked glucopyranosylamide derivatives via the in situ generation of glucosyl isoxazolines has been performed utilizing a modified Staudinger methodology. Glucopyranosylamides were derivatized with thiol
Displaying 32126 - 32150 of 74084