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Displaying 25576 - 25600 of 73960

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

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
Displaying 25576 - 25600 of 73960
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