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Displaying 16751 - 16775 of 74178

One-dimensional frequency-based spectroscopy

May 22, 2015
Author(s)
Joseph T. Hodges, A. Cygan, P. Wcislo, S. Wojtewicz, Piotr Maslowski, R. Ciurylo, D Lisak
Recent developments in optical metrology have tremendously improved the precision and accuracy of the horizontal (frequency) axis in measured spectra. However, the vertical (typically absorbance) axis is usually based on intensity measurements that are

Rectangular-Waveguide Impedance

May 22, 2015
Author(s)
Dylan F. Williams, Jeffrey A. Jargon, Uwe Arz, Paul D. Hale
We discuss the role of the wave impedance in temporal measurements in rectangular waveguide and present a simple rule-of-thumb for estimating the difference of the temporal electric and magnetic field waveforms supported by the dominant TE10 mode. We also

Uncertainties in 4-pi-beta-gamma coincidence counting

May 22, 2015
Author(s)
Ryan P. Fitzgerald, Claude Bailat, Christophe Bobin, John Keightley
The 4-pi-beta-gamma coincidence counting method and its close relatives are widely used for the primary standardization of radioactivity. Both the general formalism and specific implementation of these methods have been well-documented. In particular, the

Uncertainties in Internal Gas Counting

May 22, 2015
Author(s)
Michael P. Unterweger, L Johansson, M Rodriques, A Yunoki, Lisa R. Karam
The uncertainties in internal gas counting can, for the most part, be split into two areas: counting and sample gas measurement uncertainties and the counting uncertainties. The former includes measurements of counting and sample gas quantities and

Uncertainties in Surface Emission Rate Measurements

May 22, 2015
Author(s)
Michael P. Unterweger
The uncertainties in surface emission rates determined by gas-flow proportional counters (multiwired) will be broken down into alpha and beta emission rate determinations. Counting statistics, spectrum analysis, and electronic uncertainties will be

Uncertainty evaluation in activity measurements using ionization chambers

May 22, 2015
Author(s)
Marie Noelle Amiot, V Chiste, Ryan P. Fitzgerald, F Juget, Carine Michotte, Andrew Pearce, G Ratel
Pressurized re-entrant (or 4π) pressurized ionization chambers (ICs) connected to current- measuring electronics are used for activity measurements of photon emitting radionuclides and some beta emitters in the field of metrology and nuclear medicine. As a

Uncertainty of nuclear counting

May 22, 2015
Author(s)
Stefaan Pomme, John Keightley, Ryan P. Fitzgerald
Nuclear counting is affected by pulse pileup and system dead time which induce rate-related count loss and alter the statistical properties of the counting process. Fundamental equations are presented to predict deviations from Poisson statistics due to

Spectral reflectance variability of skin and attributing factors

May 21, 2015
Author(s)
Catherine C. Cooksey, Benjamin K. Tsai, David W. Allen
Knowledge of the spectral reflectance signature of human skin over a wide spectral range will help advance the development of sensing systems for many applications, ranging from medical treatment to security technology. A critical component of the

Multi-scale measurement for tensile behaviors of glass fiber composites at high rate loading: Fiber fragmentation behaviors in epoxy resin

May 19, 2015
Author(s)
Jae Hyun Kim, Steven P. Mates, Nathanael A. Heckert, Walter G. McDonough, Gale A. Holmes
High strength and light weight composite materials used in various structural components of aviation and automotive applications deform under high rate loading conditions during collision. Since composite structures using continuous fibers are constituted

Area Coverage in a Fixed-Obstacle Environment using Mobile Sensor Networks

May 17, 2015
Author(s)
Kamran Sayrafian, Hamid Mahboubi, Amir Aghdam
In this chapter, efficient deployment strategies for mobile sensor networks are proposed to improve the coverage area in target fields containing obstacles. The developed algorithms iteratively calcu- late and update the position of the sensors in order to

Dry graphene transfer print to polystyrene and ultra-high molecular weight polyethylene ? detailed chemical, structural, morphological and electrical characterization

May 17, 2015
Author(s)
Evegeniya Lock, Dean DeLongchamp, Scott Schmucker, Blake Simpkins, Matthew Laskoski, Shawn Mulvaney, Daniel R. Hines, Mira Baraket, Sandra Hernandez, Jeremy Robinson, Paul Sheehan, Cherno Jaye, Daniel A. Fischer, Scott Walton
In this paper we apply a transfer print approach that relies on differential adhesion to remove graphene from Cu foil to polystyrene (PS) and ultra-high molecular weight polyethylene (UHMW PE) without etching of the metal foil. The polymer surfaces are
Displaying 16751 - 16775 of 74178