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Displaying 25326 - 25350 of 73697

Present Estimates of the Differences Between Thermodynamic Temperatures and the ITS-90

January 29, 2011
Author(s)
Joachim Fischer, M. DePodesta, K. D. Hill, Michael R. Moldover, Laurent Pitre, R. Rusby, Peter Steur, Osamu Tamura, R. White, L. Wolber
In 2005, the Consultative Committee for Thermometry (CCT) recommended the creation of a Mise en pratique for the definition of the kelvin and envisioned that future versions of the Mise en pratique would recommend values of the differences between

Guide to Security for Full Virtualization Technologies

January 28, 2011
Author(s)
Murugiah P. Souppaya, Karen Scarfone, Paul Hoffman
The purpose of SP 800-125 is to discuss the security concerns associated with full virtualization technologies for server and desktop virtualization, and to provide recommendations for addressing these concerns. Full virtualization technologies run one or

The Lung Image Database Consortium (LIDC) and Image Database Resource Initiative (IDRI): A Completed Reference Database of Lung Nodules on CT Scans

January 28, 2011
Author(s)
Charles D. Fenimore, Samuel Armato, Denise Aberle, Matthew Brown, Claudia Henschke, Michael McNitt-Gray, Heber MacMahon, Geoffrey McLennan, Charles R. Meyer, Anthony P. Reeves, David F. Yankelevitz
The development of computer-aided diagnostic (CAD) methods for lung nodule detection, classification, and quantitative assessment can be facilitated through a well-characterized repository of computed tomography scans. The Lung Image Database Consortium

Use of Phosphor Image Plates for Measuring Intensities in Vacuum Ultraviolet Spectra

January 28, 2011
Author(s)
Gillian Nave, Craig J. Sansonetti, Csilla Szabo, John J. Curry, Darren Smillie
We describe the use of phosphor image plates for recording spectra in the vacuum ultraviolet (VUV) and for determining accurate relative and absolute intensities. We investigated the spatial uniformity, noise level, linearity of the response to VUV light

Neutron Activation Analysis: A Primary Method of Measurement

January 27, 2011
Author(s)
Robert R. Greenberg, Bode Peter, Fernandes Elisabete
Neutron activation analysis (NAA), based on the comparator method, has the potentials fulfilling the requirements of a primary ratio method as defined in 1998 by the CCQM of the BIPM. This thesis is evidenced in this paper in three Chapters by

New approach to calibrate the mortar flow table

January 27, 2011
Author(s)
Chiara F. Ferraris, Haleh Azari
The flow table is a standardized test that is widely used to qualify a mortar to be tested for compressive strength and air content. It is also the only standard test to quantify a mortar workability property. Therefore, the calibration of this device is

The Case for Innovations in Photovoltaics: the Nonmaterial Edge

January 26, 2011
Author(s)
Yaw S. Obeng, Kathleen C. Richardson
The limitations of current thin film and the gaps to cost efficient photovoltaic (PV) cells will be discussed in the presentation. This discussion will suggest ways to improve PV cell performance through the use of reduced dimension materials (e.g

Approximate theoretical model for the five electronic states (? = 5/2, 3/2, 3/2, 1/2, 1/2) arising from the ground 3d9 configuration in nickel halide molecules and for the rotational levels of the two ? = 1/2 states in this manifold

January 25, 2011
Author(s)
Jon T. Hougen
This paper is divided into two parts. In the first part an effective Hamiltonian for a non-rotating diatomic molecule containing only crystal-field and spin-orbit operators is set up to describe the energies of the five spin-orbit components that arise in

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
Displaying 25326 - 25350 of 73697
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