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NIST Authors in Bold

Displaying 36551 - 36575 of 74303

NFIQ Compliance Test

February 14, 2005
Author(s)
Elham Tabassi
In August 2004 NIST published a novel measure of fingerprint image quality, which can be used to estimate fingerprint match performance. The definition and methodology of NIST Fingerprint Image Quality (NFIQ) is documented in [1] and its implementation is

Challenges in Using a Reverberation Chamber for Probe Calibration

February 13, 2005
Author(s)
John M. Ladbury, Dennis Lewis, Galen H. Koepke, Randy Direen
We discuss some of the challenges associated with attempts to calibrate electromagnetic field probes in a reverberation chamber. These include immunity issues, problems related to the transient nature of the fields in a reverberation chamber, and

The Development of a High-Throughput Axisymmetric Adhesion Test

February 13, 2005
Author(s)
Aaron M. Forster, Wenhua Zhang, Christopher Stafford
There has been a growing effort to extend combinatorial and high throughput (C&HT) methods into many aspects of material science, including material property screening and materials discovery. In material science, a prevalent approach to combinatorial

Stability of a Penning trap with a quadrupole rotating electric field

February 11, 2005
Author(s)
T Hasegawa, M J. Jensen, John Bollinger
We present theoretical and experimental studies of the center-of-mass (COM) stability of ions in a Penning trap with a quadrupole rotating electric field. The rotation frequency of an ion cloud in a Penning trap determines the cloud density and shape, and

Chemical Science and Technology Laboratory: Annual Report FY2004

February 9, 2005
Author(s)
W Koch, Eric B. Steel, Ellyn S. Beary
This report summarizes the research and services provided by the Chemical Science and Technology Laboratory of the National Institute of Standards and Technology for Fiscal Year 2004. The report includes: a general overview of the laboratory's activities

Thermodynamic Properties of 2-Methylquinoline and 8-Methylquinoline

February 9, 2005
Author(s)
Robert D. Chirico, William Steele
Measurements leading to the calculation of the standard thermodynamic properties for gaseous 2-methylquinoline (Chemical Abstracts registry number [91-63-4]) and 8 methylquinoline (Chemical Abstracts registry number [611-32-5]) are reported. Experimental

A Hybrid Lagrangian Variational Method for Bose-Einstein Condensates in Optical Lattices

February 7, 2005
Author(s)
M Edwards, L M. DeBeer, M Demenikov, J Galbreath, B Nelson, Charles W. Clark
Solving the Gross--Pitaevskii (GP) equation describing a Bose--Einstein condensate (BEC) immersed in an optical lattice potential can be a numerically demanding task. We present a variational technique for providing fast, accurate solutions of the GP

Toward chip-scale atomic clocks

February 7, 2005
Author(s)
C. T-C. Nguyen, John Kitching
This paper describes work towards the use of integrated microelectromechanical systems (MEMS) technology to shrink atomic clocks from their present-day table-top sizes down to only one cubic-centimeter, while retaining exceptional timing stability on the

End States in One-Dimensional Chains

February 4, 2005
Author(s)
Jason Crain, Daniel T. Pierce
End states-the zero-dimensional analogs of the two-dimensional states that occur at a crystal surface-were observed at the ends of one-dimensional atom chains that were self-assembled by depositing gold on the vicinal Si(553) surface. Scanning tunneling

PVTx Measurements and Crossover Equation of State of Pure n-Hexane and Dilute Aqueous n-Hexane Solutions in the Critical and Supercritical Regions

February 2, 2005
Author(s)
Ilmutdin Abdulagatov, Emil Bazaev, Joe W. Magee, Sergei B. Kiselev, James F. Ely
The PVTx relationship of aqueous n-hexane solutions (0.0201, 0.082 and 0.8500 mole fraction of n-hexane) has been measured in the near-critical and supercritical regions with a constant-volume piezometer. Measurements were made on the critical isotherm of

A Rigorous Attempt to Verify Interstellar Glycine

February 1, 2005
Author(s)
Lewis E. Snyder, Francis J. Lovas, J M. Hollis, Douglas N. Friedel, P R. Jewell, A Remijan, Vadim V. Ilyushin, E A. Alekseev, S K. Dyubko
In 2003, Kuan, Charnley, and co-workers claimed the detection of interstellar glycine (NH2 CH2COOH) based on the detection of 27 lines in 19 different spectral bands in one or more of the sources Sgr B2(N-LMH), Orion KL, and W51 e1/e2. They supported their

Adaptive Grid Refinement for a Model of Two Confined and Interacting Atoms

February 1, 2005
Author(s)
William F. Mitchell, Eite Tiesinga
We have applied adaptive grid refinement to solve a two-dimensional Schroedinger equation in order to study the feasibility of a quantum computer based on extremely-cold neutral alkali-metal atoms. Qubits are implemented as motional states of an atom

An Atomic Clock on a Chip

February 1, 2005
Author(s)
John E. Kitching
This article described recent research in the Time and Frequency Division at NIST to develop highly miniaturized atomic frequency references using microfabrication technologies. We discuss the overall physics package design, fabrication of individual

Artifacts That Mimic Ballistic Magnetoresistance

February 1, 2005
Author(s)
William F. Egelhoff Jr., L Gan, H Ettedgui, Y Kadmon, Cedric J. Powell, P J. Chen, Alexander J. Shapiro, Robert McMichael, J Mallett, Thomas P. Moffat, Mark D. Stiles, Erik B. Svedberg
We have investigated the circumstances underlying recent reports of very large values of ballistic magntoresistance (BMR) in nanocontacts between magnetic wires. We find that the geometries used are subject to artifacts due to motion of the wires that

Coincidence in the Two-Photon Spectra of Li and Li 2 at 735 nm

February 1, 2005
Author(s)
W DeGraffenreid, Craig J. Sansonetti
A coincidence between the 2S - 3S two-photon transition in the spectrum of atomic Li and the X 1Sg+ E 1Sg two-photon ro-vibrational series of 7Li2 was observed near 735 nm in a heat pipe oven using a tunable laser and thermionic diode detection scheme. The

Combinatorial Peel Tests for the Characterization of Adhesion Behavior of Polymeric Films

February 1, 2005
Author(s)
R Song, Martin Chiang, A J. Crosby, Alamgir Karim, Eric J. Amis, Naomi Eidelman
The self-adhesion behavior of an optically smooth poly(methyl methacrylate) (PMMA) thin film (ca.. 100 nm) on different evaporated metal substrates has been investigated using a combinatorial method approach. In this investigation through high-throughput

Conformance Testing of the Government Smart Card

February 1, 2005
Author(s)
Barbara Guttman
The National Software Reference Library (NSRL) of the U.S. National Institute of Standards and Technology (NIST) collects software from various sources and publishes file profiles computed from this software (such as MD5 and SHA-1 hashes) as a Reference
Displaying 36551 - 36575 of 74303