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Search Publications

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Displaying 5726 - 5750 of 74364

FPGA Implementation of a Low Latency and High SFDR Direct Digital Synthesizer for Resource-Efficient Quantum-Enhanced Communication

October 15, 2020
Author(s)
FNU Nur Fajar Rizqi Annafianto, Jabir Marakkarakath Vadakkepurayil, Ivan Burenkov, Hasan Urgurdag, Abdella Battou, Sergey Polyakov
In most modulation schemes for a telecommunication system, a fast and efficient sinusoidal signal generator is needed. Here we report on an FPGA implementation of a versatile CORDIC Based Direct Digital Synthesizer (DDS). Most commercial lightwave

Structural Properties of Kerogens with Different Maturities

October 15, 2020
Author(s)
Wei-Shan Chiang, Jin-hong Chen, David Jacobi, Taner N. Yildirim
The thermogenic transformation of kerogen into hydrocarbons accompanies the development of a pore network within the kerogen that serves as gas storage locations both in pore space and surface area for adsorbed gas within the source rock. Therefore, the

Quantum-Critical Scale Invariance in Transition Metal Alloy

October 14, 2020
Author(s)
Yasuyuki Nakajima, Tristin Metz, Christoper Eckberg, Kevin Kirshenbaum, Alex Hughes, Renxiong Wang, Limin Wang, Shanta Saha
Quantum-mechanical fluctuations between competing phases at Τ = 0 induce exotic finite-temperature collective excitations that are not described by the standard Landau Fermi liquid framework [1-4]. These excitations exhibit anomalous temperature

Characterization of a Josephson Junction Comb Generator

October 13, 2020
Author(s)
Akim Babenko, Alirio De Jesus Soares Boaventura, Nathan Flowers-Jacobs, Justus Brevik, Anna Fox, Dylan Williams, Zoya Popovic, Paul Dresselhaus, Samuel P. Benz
We present a new type of microwave frequency combs with a potentially calculable pulse shape. The device is an array of 1500 Josephson junctions (JJs) connected in series along a transmission line. The pulse generation is based on the nonlinearity of the

Deterministic Move Lists for Federal Incumbent Protection in the CBRS Band

October 13, 2020
Author(s)
Michael R. Souryal, Thao T. Nguyen
The 3.5 GHz citizens broadband radio service (CBRS) band in the U.S. is a key portion of mid- band spectrum shared between commercial operators and existing federal and non-federal incumbents in the band. To protect the federal incumbents from harmful

Dynamics of Hydroxyl Anions Promotes Lithium Ion Conduction in Antiperovskite Li 2 OHCl

October 13, 2020
Author(s)
Fei Wang, Hayden Evans, Kwangnam Kim, Liang Yin, Yiliang Li, Ping-Chun Tsai, Jue Liu, Saul H. Lapidus, Craig Brown, Donald J. Siegel, Yet-Ming Chiang
Li 2OHCl is an exemplar of the anti-perovskite family of ionic conductors, for which high ionic conductivities have been reported, but in which the atomic-level mechanism of ion migration is unclear. The stable phase is highly defective, having 1/3 of the

Integrating Cybersecurity and Enterprise Risk Management (ERM)

October 13, 2020
Author(s)
Kevin M. Stine, Stephen D. Quinn, Gregory A. Witte, Robert Gardner
The increasing frequency, creativity, and severity of cybersecurity attacks means that all enterprises should ensure that cybersecurity risk is receiving appropriate attention within their enterprise risk management (ERM) programs. This document is

Orientation Mapping of Graphene Using 4D STEM-in-SEM

October 13, 2020
Author(s)
Benjamin W. Caplins, Jason D. Holm, Ryan M. White, Robert R. Keller
A scanning diffraction technique is implemented in the scanning electron microscope. The technique, referred to as 4D STEM-in-SEM (four-dimensional scanning transmission electron microscopy in the scanning electron microscope), collects a diffraction

Local negative permittivity and topological-phase transition in polar skyrmions

October 12, 2020
Author(s)
Sujit Das, Zijian Hong, Vladimir Stoica, Mauro A. Goncalves, Yu-Tsun Shao, Eric Parsonnet, Eric J. Marksz, Sahar Saremi, Margaret McCarter, A Reynoso, Chris Long, Aaron Hagerstrom, D Meyers, V Ravi, B Prasad, H Zhou, Z Zhang, H Wen, F Gomez-Ortiz, P Garcia-Fernandez, J Bokor, J Iniguez, J Freeland, Nate Orloff, J Junquera, Long-Qing Chen, Sayeef Salahuddin, David A. Muller, L Martin, R. Ramesh
Topological solitons such as magnetic skyrmions have drawn enormous attention as stable quasi- particle-like objects. The recent discovery of polar vortices and skyrmions in ferroelectric- oxide superlattices, exhibiting exotic physical phenomena, has

Nonlinearity and ionization in Xe: Experiment-based calibration of a numerical model

October 12, 2020
Author(s)
Joseph Tolliver, Sina Zahedpour, Jared Wahlstrand, H M. Milchberg, Miroslav Kolesik
A model for the optical response of Xenon, including the nonlinear polarization and ionization rate, is calibrated with the help of space-and-time resolved measurements. Utilizing an idea of universal functional form for the response as a function of the

Improved plutonium and americium photon branching ratios from microcalorimeter gamma spectroscopy

October 11, 2020
Author(s)
M. D. Yoho, K. E. Koehler, Dan Becker, Douglas Bennett, M. H. Carpenter, M. P. Croce, J. D. Gard, John Mates, D. J. Mercer, Nathan Ortiz, Dan Schmidt, C. M. Smith, Daniel Swetz, A. D. Tollefson, Joel Ullom, Leila R. Vale, Abigail Wessels, D. T. Vo
Photon branching ratios are critical input data for activities such as nuclear materials protection and accounting because they allow material compositions to be extracted from measurements of gamma-ray intensities. Uncertainties in these branching ratios

Storing and retrieving wavefronts with resistive temporal memory

October 10, 2020
Author(s)
Advait Madhavan, Mark D. Stiles
We extend the reach of temporal computing schemes by developing a memory for multi-channel temporal patterns or "wavefronts." This temporal memory re-purposes conventional one-transistor-one-resistor (1T1R) memristor crossbars for use in an arrival-time

Trojan Detection Evaluation: Finding Hidden Behavior in AI Models

October 10, 2020
Author(s)
Michael Paul Majurski, Derek Juba, Timothy Blattner, Peter Bajcsy, Walid Keyrouz
Neural Networks are trained on data, learn relationships in that data, and then are deployed to the world to operate on new data. For example, a traffic sign classification AI can differentiate stop signs and speed limit signs. One potential problem is

Position-Dependent Diffusion Dynamics of Entangled Polymer Melts Nanoconfined by Parallel Immiscible Polymer Films

October 9, 2020
Author(s)
Kyong-Il Jo, Yonghoon Oh, Tae-Ho Kim, Joona Bang, Guangcui Yuan, Sushil K. Satija, Bong J. Sung, Jaseung Koo
The morphological structure and dynamics of confined polymers adjacent to the polymer–polymer interface have a profound effect on determining the overall physical properties of polymer blends. We measured the diffusion dynamics of polymethylmethacrylate

Extrapolation And Interpolation Strategies For Efficiently Estimating Structural Observables As a Function Of Temperature And Density

October 8, 2020
Author(s)
Jacob I. Monroe, Harold Wickes Hatch, Nathan NMN Mahynski, M. Scott Shell, Vincent K. Shen
Thermodynamic extrapolation has previously been used to predict arbitrary structural observables in molecular simulations at temperatures (or relative chemical potentials in open- system mixtures) different from those at which the simulation was performed

Rheology of Crystallizing LLDPE

October 8, 2020
Author(s)
Marat Andreev, David Nicholson, Anthony Kotula, Jonathan D. Moore, Jaap Den Doelder, Gregory C. Rutledge
Polymer crystallization occurs in many plastic manufacturing processes, from injection molding to film blowing. Linear low-density polyethylene (LLDPE) is one of the most commonly processed polymers, wherein the type and extent of short chain branching

Two-temperature preparation method for PDMS-based canine training aids for explosives

October 8, 2020
Author(s)
William A. MacCrehan, Mimy Young, Michele M. Schantz, T C. Angle, Paul Waggoner, Terrance Fisher
Training aids based on vapor capture-and-release into a flexible polymer, polydimethylsiloxane (PDMS), have proven successful in canine detection of explosives that have volatile or semi- volatile odorants. To enhance the rate of odor capture for less

Cybersecurity Framework Version 1.1 Manufacturing Profile

October 7, 2020
Author(s)
Keith A. Stouffer, Timothy Zimmerman, CheeYee Tang, Michael Pease, Jeffrey Cichonski, John McCarthy
This document provides the Cybersecurity Framework (CSF) Version 1.1 implementation details developed for the manufacturing environment. The "Manufacturing Profile" of the CSF can be used as a roadmap for reducing cybersecurity risk for manufacturers that
Displaying 5726 - 5750 of 74364