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Displaying 18901 - 18925 of 73994

X-Ray microbeam measurements of long range internal stresses in commercial purity aluminum processed by multiple passes of equal-channel angular pressing

December 15, 2014
Author(s)
Lyle E. Levine, Thien Phan, I-Fang Lee, Jonathan Z. Tischler, Huang Yi, Alan G. Fox, Terrance G. Langdon, Mike Kassner
X-ray microbeam diffraction was used to measure long range internal stresses (LRIS) in the grain/subgrain interiors of commercial purity aluminum processed by equal-channel angular pressing for up to 8 passes. The LRIS values at +4.9o off the axial

Structure and Function of the Membrane Anchoring Self-Assembled Monolayers

December 14, 2014
Author(s)
David J. Vanderah, Tadas Ragaliauskas, Mindaugas Mickevicius, Mariya Jankunec, Gediminas Niaura, Gintaras Valincius, Bozena Rakovska
Structure of the self-assembled monolayers (SAMs) used to anchor phospholipid bilayers to surfaces affects the functional properties of the tethered bilayer membranes (tBLMs). SAMs of the same surface composition differing in the lateral distribution of

Device-Level Experimental Observations of NBTI-Induced Random Timing Jitter

December 13, 2014
Author(s)
Guangfan Jiao, Jiwu Lu, Jason Campbell, Jason Ryan, Kin P. Cheung, Chadwin D. Young, Gennadi Bersuker
This work utilizes device-level eye-diagram measurements to examine NBTI-induced changes in timing jitter at circuit speeds. The measured jitter is examined for a variety of ring-oscillator and pseudo-random gate patterns. The ring-oscillator patterns were

Behavior of Unrestrained and Restrained Steel Columns Adjacent to Localized Fire

December 12, 2014
Author(s)
Chao Zhang, John L. Gross, Therese P. McAllister, Guo-Qiang Li
Steel columns may be exposed to thermal radiation from localized burning of a fire source nearby. Current structural fire design methods are based on uniform heating and, therefore, uniform temperature conditions, and no practicable methods are provided to

Behavior of Unrestrained and Restrained Steel Columns Surrounded by Localized Fire

December 12, 2014
Author(s)
Chao Zhang, John L. Gross, Therese P. McAllister, Guo-Qiang Li
Real fires start from localized burning, and will not develop to flashover if in an open space or in large open-plan compartments. Temperatures of gas and exposed steel columns in localized fires are not uniform. Current structural fire design methods are

MECHANICS ANALYSIS OF MOLAR TOOTH SPLITTING

December 12, 2014
Author(s)
Amir Barani, Brian R. Lawn, Mark Bush, Herzl Chai
A model for the splitting of teeth from wedge loading of molar cusps from a round indenting object is presented. The model is developed in two parts: first, a simple 2D fracture mechanics configuration with the wedged tooth simulated by a compact tension

Natural Scene Statistics in Infrared Images

December 12, 2014
Author(s)
Nicholas G. Paulter Jr., Todd R. Goodall, Alan C. Bovik
Natural Scene Statistics (NSS) produces powerful perceptually relevant tools that have been highly successful in image quality analysis of visible light images. These NSS capture statistical regularities in the physical world and thus can be applicable to

PM Noise Measurement at W-Band

December 12, 2014
Author(s)
Archita Hati, Craig W. Nelson, David A. Howe
We present improved performance for a 92 - 96 GHz cross-spectrum phase modulated (PM) noise measurement system previously reported. The system is principally designed to measure amplifiers in pulsed mode with a duty cycle of 10% to 100% (CW) at a given

Quantitative Evidence for Organic Peroxy Radical Photochemistry

December 12, 2014
Author(s)
William S. McGivern, Joseph Klems
Quantitative evidence for the importance of alkyl peroxy photochemistry in the formation of secondary organic aerosol at 254 nm. Dodecanoic acid has been oxidized extensively in a flow cell by photolytically generated hydroxyl radicals to create particles

Short-Range Correlations in the Magnetic Ground State of Na 4 Ir 3 O 8

December 12, 2014
Author(s)
Rebecca Dally, Tom Hogan, Alex Amato, Chris Baines, Jose Rodriguez Rivera, Michael J. Graf, Stephen D. Wilson
The magnetic ground state of the J eff = 1/2 hyper-Kagome lattice in Na 4Ir 3O 8 is explored via combined bulk magnetization, muon spin relaxation, and neutron scattering measurements. A short-range, frozen, state comprised of quasi-static moments develops

Tunable Spin-Orbit Coupling via Strong Driving in Ultracold Atom Systems

December 12, 2014
Author(s)
Ian B. Spielman, Lindsay J. LeBlanc, Ross A. Williams, Matthew C. Beeler, Chunlei Qu, Ming Gong, Chuanwei Zhang
Spin-orbit coupling (SOC) is an essential ingredient in topological materials, conventional and quantum-gas based alike. Engineered spin-orbit coupling in ultracold atom systems unique in their experimental control and measurement opportunities provides a

Cryocooled 10 V Programmable Josephson Voltage Standard

December 11, 2014
Author(s)
Alain Rufenacht, Logan A. Howe, Anna E. Fox, Robert E. Schwall, Paul D. Dresselhaus, Charles J. Burroughs, Samuel P. Benz
Improvements in fabrication and packaging of our 10 V Programmable Josephson Voltage Standard circuits have enabled the successful operation of these devices on a cryocooler. Limited cooling power and temperature oscillations at the chip must not

Cryocooled 10 V Programmable Josephson Voltage Standard

December 11, 2014
Author(s)
Alain Rufenacht, Logan A. Howe, Anna Fox, Robert E. Schwall, Paul Dresselhaus, Charles J. Burroughs, Samuel Benz
Implementation of programmable Josephson voltage standard (PJVS) circuits on cryocooler at 4 K is a challenge. The limited cooling power of the cryocoolers has to balance the heat dissipated by the PJVS circuit in order to maintain a stable temperature

DATA ANALYTICS USING SIMULATION FOR SMART MANUFACTURING

December 11, 2014
Author(s)
Guodong Shao, Sanjay Jain, Seungjun Shin
Manufacturing organizations are able to accumulate large amounts of plant floor production and environmental data due to advances in data collection, communications technology, and use of standards. The challenge has shifted from collecting a sufficient

Quantifying CD4 receptor protein in two human CD4+ lymphocyte preparations for quantitative flow cytometry

December 11, 2014
Author(s)
Meiyao M. Wang, Martin Misakian, Hua-Jun He, Peter Bajcsy, Jeffrey M. Davis, Kenneth D. Cole, Illarion Turko, Lili Wang, Fatima Abbasi
For quantitative flow cytometry, a biological cell reference material with a known biomarker expression level is needed to transform a linear arbitrary fluorescence intensity scale obtained with fluorescent microspheres to an antibody bound per cell (ABC)

VIRTUAL FACTORY REVISITED FOR MANUFACTURING DATA ANALYTICS

December 11, 2014
Author(s)
Sanjay Jain, Guodong Shao
Development of a data analytics application for manufacturing is best when tested with large sets of data. It is usually difficult for application developers to find access to real manufacturing data streams for testing new data analytics applications

A self-calibrating optomechanical force sensor with femtonewton resolution

December 10, 2014
Author(s)
John T. Melcher, Julian Stirling, Felipe Guzman, Jon R. Pratt, Gordon A. Shaw
We report the development of an ultrasensitive optomechanical sensor designed to improve the accuracy and precision of force measurements with atomic force microscopy. The sensors achieve quality factors of 4.3x10^6 (a 100-fold improvement over quartz

Computing elastic moduli on 3-D X-ray computed tomography image stacks

December 10, 2014
Author(s)
Edward Garboczi, Volodymyr Kushch
A common numerical task is to compute the effective elastic properties of a random composite material based on its microstructure by operating on a 3D digital image of the microstructure obtained via X-ray computed tomography (CT). The 3-D image is usually

Experimental Bounds on Classical Random Field Theories

December 10, 2014
Author(s)
Joffrey K. Peters, Sergey V. Polyakov, Jingyun Fan, Alan L. Migdall
Alternative theories to quantum mechanics motivate important fundamental tests of our understanding and description of the smallest physical systems. Here we place experimental limits on those classical field theories which result in power-dependent
Displaying 18901 - 18925 of 73994
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