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Displaying 11026 - 11050 of 74079

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November 30, 2017
Author(s)
Chung Tong Hu, David F. Ferraiolo, Ramaswamy Chandramouli, David R. Kuhn
Until now, ABAC research has been documented in hundreds of research papers, but not consolidated in book form. This book explains ABAC's history and model, related standards, verification and assurance, applications, and deployment challenges; Specialized

Measurements of the Newtonian Constant of Gravitation, G

November 30, 2017
Author(s)
Christian Rothleitner, Stephan Schlamminger
The Newtonian Constant of Gravitation G seems to be the fundamental constant that is most difficult to measure accurately. In the past three decades more than a dozen precision measurements were performed. Unfortunately the scatter of the data points is

Quantifying Variance Components for Repeated Scattering-Parameter Measurements

November 30, 2017
Author(s)
Amanda Koepke, Jeffrey Jargon
We quantify random uncertainties for scattering-parameters repeatedly measured with a vector network analyzer (VNA), focusing on variations due to multiple calibrations, disconnects, and repeat measurements. We describe a two-stage nested design, which

Sensors for Safe, Collaborative Robots in Smart Manufacturing

November 30, 2017
Author(s)
Jeremy Marvel
The U.S. National Institute of Standards and Technology (NIST) is developing performance metrics for collaborative robotic systems for smart manufacturing applications. Using a suite of sensor platforms, feedback mechanisms, and novel test artifacts, NIST

Analysis of PFAAs in American alligators Part 1: Concentrations in alligators harvested for consumption during South Carolina public hunts.

November 29, 2017
Author(s)
Jessica Tipton, Louis J. Guillette, Benjamin B. Parrott, Thomas R. Rainwater, Jessica L. Reiner
Environmental contamination resulting from the production or release of harmful chemicals can lead to negative consequences for wildlife and human health. Perfluorinated alkyl acids (PFAAs) were historically produced as protective coatings for many

Analysis of PFAAs in American alligators Part 2: Potential dietary exposure of South Carolina hunters from recreationally harvested alligator meat

November 29, 2017
Author(s)
Jessica Tipton, Louis J. Guillette, Susan Lovelace, Benjamin B. Parrott, Thomas R. Rainwater, Jessica L. Reiner
Exposure to perfluorinated alkyl acids (PFAAs) has been linked to many harmful health effects including reproductive disorders, developmental delays, and altered liver and kidney function. Most human exposure to environmental contaminants, including PFAAs

Annual Manufacturing Review: 2017

November 29, 2017
Author(s)
Douglas Thomas
The purpose of this report is to characterize US innovation and industrial competitiveness in manufacturing. It includes tracking domestic manufacturing activity and its supply chain in order to develop a quantitative depiction of U.S. manufacturing in the

Quasi-Two-dimensional Phase Transition of Methane Adsorbed in Cylindrical Silica Mesopores

November 29, 2017
Author(s)
Daniel W. Siderius, William P. Krekelberg, Wei-Shan NMN Chiang, Vincent K. Shen, Yun Liu
Using Monte Carlo and molecular dynamics simulations, we examine the adsorption of methane in cylindrical silica mesopores in an effort to understand a possible phase transition of adsorbed methane in MCM-41 and SBA-15 silica that was previously identified

Tissue Distribution of Perfluoroalkyl Acids (PFAAs) and Health Status in Wild Mozambique Tilapia (Oreochromis mossambicus) from Loskop Dam, Mpumalanga, South Africa

November 29, 2017
Author(s)
Jacqueline T. Bangma, Jessica L. Reiner, Hannes Botha, Theresa M. Cantu, Marco Gouws, Matthew P. Guillette, Jeremy P. Koelmel, Wilmien Luus-Powell, Olivia Rynders, Joseph Sara, Willem J. Smit, John Bowden
This study collected male Mozambique tilapia (Oreochromis mossambicus) from Loskop Dam, Mpumalanga, South Africa in 2014 and 2016 to investigate the levels of 15 perfluoroalkyl acids (PFAAs) across six tilapia tissues. Nine of the 15 PFAAs were detected

Ultra-high contrast coherent population trapping resonances in a cold-atom microwave clock

November 29, 2017
Author(s)
Xiaochi Liu, V. I. Yudin, A. V. Taichenachev, John Kitching, Elizabeth Donley
A cold-atom coherent population trapping clock can achieve a better long-term frequency stability than similar clocks based on vapor cells, since long interrogation periods are possible without introducing systematic frequency shifts from buffer gases

Characterization of Transmission Lines with Nonlinear Dielectric Materials

November 28, 2017
Author(s)
Aaron M. Hagerstrom, Christian J. Long, Nathan D. Orloff, James C. Booth, Eric J. Marksz
Nonlinear transmission lines are interesting for two broad reasons: first, they have several direct device applications (i.e. harmonic generation, and phase shifters), and second, they provide a way to characterize nonlinear materials at mm-wave

Contributions of precision engineering to the revision of the SI

November 28, 2017
Author(s)
Stephan Schlamminger, Harald Bosse, Horst Kunzmann, Jon R. Pratt, Ian Robinson, Michael de Podesta, Paul Shore, Paul Morantz
All measurements performed in science and industry are based on the International System of Units, the SI. It has been proposed to revise the SI following an approach which had already been implemented for the redefinition of the unit of length, the metre

Establishing Traceability for SOLT Calibration Kits*

November 28, 2017
Author(s)
Ronald A. Ginley
Establishing traceability for a measurement is very important so that the results of the measurement can be used in a common framework for comparisons and understanding. The standard source of traceability for Short-Open-Load-Thru (SOLT) calibrations has

Free Surface Relaxations of Star-Shaped Polymer Films

November 28, 2017
Author(s)
Alexandros Chremos, Bradley R. Frieberg, Emmanouil Glynos, Kyle Johnson, Hengxi Yang, Suresh Narayanan, Peter F. Green, Georgios Sakellariou
X-ray photon correlation spectroscopy (XPCS) studies show that the viscosities of thin film linear chain polymers at temperatures sufficiently high above the bulk glass transition temperature Tg bulk are equal to the bulk zero shear viscosities. The free

Helical Level Structure of Dirac Potential Wells

November 28, 2017
Author(s)
Daniel T. Walkup, Joseph A. Stroscio
In graphene and other massless 2D Dirac materials, Klein tunneling compromises electron confinement, and momentum-space contours can be assigned a Berry phase which is either zero or π. Consequently, in such systems the energy spectrum of circular

Multimodality of Structural, Electrical, and Gravimetric Responses of Intercalated MXenes to Water

November 28, 2017
Author(s)
Eric S. Muckley, Michael Naguib, Hsiu-Wen Wang, Lukas Vlcek, Naresh C. Osti, Robert L. Sacci, Xiahan Sang, Raymond R. Unocic, Yu Xie, Madhu Sudan Tyagi, Eugene Mamontov, Katharine L. Page, Paul R. C. Kent, Jagjit Nanda, Ilia N. Ivanov
Understanding of structural, electrical and gravimetric peculiarities of water vapor interaction with ion-intercalated MXenes used to design of a multimodal humidity sensor. Neutron scattering coupled to molecular dynamics and ab initio calculations showed

Probing the dielectric response of the interfacial buffer layer in epitaxial graphene via optical spectroscopy

November 28, 2017
Author(s)
Heather M. Hill, Albert Rigosi, Sugata Chowdhury, Yanfei Yang, Nhan Van Nguyen, Francesca Tavazza, Randolph Elmquist, David B. Newell, Angela R. Hight Walker
Monolayer epitaxial graphene (EG) is a suitable candidate for a variety of electronic applications. One advantage of EG growth on the Si face of SiC is that it develops as a single crystal, as does the layer below, referred to as the interfacial buffer

Protecting Controlled Unclassified Information in Nonfederal Information Systems and Organizations [including updates as of 11-28-2017]

November 28, 2017
Author(s)
Ronald S. Ross, Patrick Viscuso, Gary Guissanie, Kelley L. Dempsey, Mark Riddle
[Superseded by SP 800-171 Rev. 1 (December 2016, updated 02/20/2018): https://doi.org/10.6028/NIST.SP.800-171r1] The protection of Controlled Unclassified Information (CUI) while residing in nonfederal information systems and organizations is of paramount

Rydberg Atom Electric-Field Metrology

November 28, 2017
Author(s)
Joshua A. Gordon, Christopher L. Holloway, Matthew T. Simons
We present a technique which shows great promise for realizing an atomic standard measurement of RF fields that is intrinsically calibrated, directly linked to the SI and atomic structural constants. This technique relies on the reponse of Rydberg atoms to
Displaying 11026 - 11050 of 74079