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Displaying 16701 - 16725 of 74137

Characterizing the three-dimensional structure of block copolymers via sequential infiltration synthesis and scanning transmission electron tomography

May 26, 2015
Author(s)
Tamar Segal-Peretz, Jonathan P. Winterstein, Manolis Doxastakis, Abelardo Ramirez-Hernandez, Mahua Biswas, Jiaxing Ren, Hyo S. Suh, Seth B. Darling, James Alexander Liddle, Jeffrey Elam, Juan J. de Pablo, Nestor Zaluzec, Paul Nealey
Understanding and controlling the three-dimensional structure of block copolymer (BCP) thin films is critical for utilizing these materials for sub-20 nm nanopatterning in semiconductor devices, as well as in membranes and solar cell applications

UWB Signal Processing: Projection, B-Splines, and Modified Gegenbauer Bases

May 25, 2015
Author(s)
Howard S. Cohl, Stephen D. Casey
Ultra-wide band (UWB) systems require either rapidly changing or very high sampling rates. Conventional analog-to-digital devices have limited dynamic range. We investigate UWB signal processing via a basis projection method and a basis system designed for

A real microstructural model for cement concrete modeling

May 24, 2015
Author(s)
Edward J. Garboczi, Yang Lu, Stephen Thomas
Existing concrete microstructural models of particles embedded in matrix materials are only represented by regular shape particles like spheres, ellipsoids, or multi-faceted polyhedrons. However, the real particle shapes are more complex and sometimes play

Evaluating Bug Finders: Test and Measurement of Static Code Analyzers

May 23, 2015
Author(s)
Aurelien M. Delaitre, Bertrand C. Stivalet, Elizabeth N. Fong, Vadim Okun
Software static analysis is one of many options for finding bugs in software. Like compilers, static analyzers take a program as input. This paper covers tools that examine source code--without executing it--and output bug reports. Static analysis is a

Real-time x-ray scattering studies of film formation in high performing small-molecule organic solar cells

May 23, 2015
Author(s)
Sebastian Engmann, Felicia A. Bokel, Andrew Herzing, Hyun W. Ro, Dean DeLongchamp, Lee J. Richter, Claudio Girotto, Bruno Caputo
We have studied the influence of the additive diiodoctane on the formation dynamics of high performance bulk heterojunction (BHJ) films based the small molecule donor 7,7'-(4,4bis(2- ethylhexyl)-4H-silolo[3,2-b:4,5-b']dithiophene-2,6-diyl)bis(6-fluoro-5-(5

Calibration of channel mismatch in time-interleaved real-time digital oscilloscopes

May 22, 2015
Author(s)
Jeffrey A. Jargon, Paul D. Hale, Peter J. Jeavons, John B. Schlager, Andrew M. Dienstfrey, Joo-Gwang Lee, Chihyun Cho
A novel method is proposed for the calibration of channel mismatch in a time-interleaved real- time digital oscilloscope (RTDO). The method only requires a transfer function of time- interleaved ADCs (TIADCs), and also proposes measurement schemes of the

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
Displaying 16701 - 16725 of 74137