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Displaying 18001 - 18025 of 74178

Characterization of Metal Powders Used for Additive Manufacturing

September 16, 2014
Author(s)
John A. Slotwinski, Edward J. Garboczi, Paul E. Stutzman, Chiara F. Ferraris, Stephanie S. Watson, Max A. Peltz
Additive manufacturing (AM) techniques can produce complex, high-value metal parts, with potential applications as critical parts such as those found in aerospace components. The production of AM parts with consistent and predictable properties requires

Porosity Measurements and Analysis for Metal Additive Manufacturing Process Control

September 16, 2014
Author(s)
John A. Slotwinski, Edward J. Garboczi, Keith M. Hebenstreit
Additive manufacturing techniques can produce complex, high-value metal parts, with potential applications as critical metal components such as those found in aerospace engines and as customized biomedical implants. Material porosity in these parts is

A perspective on the origin of lubricity in petroleum distillate motor fuels

September 15, 2014
Author(s)
Peter Y. Hsieh, Thomas J. Bruno
Lubricity, or a substance's effect on friction and wear between two surfaces in relative motion, is affected by both chemical and physical mechanisms present at a sliding contact. The inherent lubricity of distillate motor fuels stems from surface-active

An Average Enumeration Method of Hyperspectral Imaging Data for Quantitative Evaluation of Medical Device Surface Contamination

September 15, 2014
Author(s)
Hanh Le, Moon Kim, Jeeseong C. Hwang, Yi Yang, Pawneena U-Thainual, Jin Kang, Do-Hyun Kim
We propose a quantification method called Mapped Average Principal component analysis Score (MAPS) to enumerate the contamination coverage on common medical device surfaces. The method was adapted from conventional Principal Component Analysis (PCA) on non

Physics-based Electro-thermal Saber Model and Parameter Extraction for High-Voltage SiC Buffer IGBTs

September 15, 2014
Author(s)
Tam H. Duong, Allen R. Hefner Jr., Jose M. Ortiz, Sei-Hyung Ryu , Edward VanBrunt, Lin Cheng, Scott Allen, John W. Palmour
The purpose of this paper is to present a physics-based electro-thermal Saber model and parameter extraction sequence for high-voltage SiC buffer layer n-channel insulated gate bipolar transistors (IGBTs). This model was developed by modifying and

Quantum correlations in a noisy neutron interferometer

September 15, 2014
Author(s)
Michael G. Huber, Muhammad D. Arif, Christopher Wood, D G. Cory, M. O. Abutaleb, Dimitry A. Pushin
We investigate quantum coherences in the presence of noise by entangling the spin and path degrees of freedom of the output neutron beam from a noisy three-blade perfect crystal neutron interferometer. We nd that in the presence of dephasing noise on the

Simulation of the Hydration Kinetics and Elastic Moduli of Cement Mortars by Microstructural Modeling

September 15, 2014
Author(s)
Luca Valentini, Matteo Parisatto, Vincenzo Russo, Giorgio Ferrari, Jeffrey W. Bullard, Ross J. Angel, Maria C. Dalconi, Gilberto Artioli
The ability of the VCCTL microstructural model to predict the hydration kinetics and elastic moduli of cement materials was tested by coupling a series of computer simulations and laboratory experiments, using different cements. The novel aspects of this

Technique for AFM Tip Characterization

September 15, 2014
Author(s)
Ndubuisi G. Orji, Ronald G. Dixson, Hiroshi Itoh, Chumei Wang
In atomic force microscopy (AFM) metrology, the scanning tip is a major source of uncertainty. Images taken with an AFM show an apparent broadening of feature dimensions due to the finite size of the tip. An AFM image is a combination of the feature shape

The IEEE VSSC/1622: Voting System Standards

September 15, 2014
Author(s)
John P. Wack
This article presents an overview of the IEEE VSSC/1622 and its working groups. It contains information as to why a common data format for voting systems is needed and how VSSC/1622 standards will improve voting system operations and use. It contains

Bromination of marine particulate organic matter through oxidative mechanisms

September 14, 2014
Author(s)
Bruce D. Ravel, Alessandra C. Leri, Kathleen Thornton, Lawrence M. Mayer
Although bromine is considered conservative in seawater, it exhibits a well established correlation with organic carbon in marine sediments. This carbon-bromine association was recently attributed to covalent bonding, with organobromine in sinking

A Hybrid CPU-GPU System for Stitching Large Scale Optical Microscopy Images

September 12, 2014
Author(s)
Timothy Blattner, Walid Keyrouz, Joe Chalfoun, Bertrand C. Stivalet, Mary C. Brady, Shujia Zhou
Researchers in various fields are using optical microscopy to acquire very large images, 10K--200K of pixels per side. Optical microscopes acquire these images as grids of overlapping partial images (thousands of pixels per side) that are then stitched

Mutual Cross Modulation of Two Laser Beams at the Individual-Photon Level

September 12, 2014
Author(s)
Michael Gullans, Kristin M. Beck, Qian Lin, M D. Lukin, Vladan Vuletic, Wenlan Chen
The realization of deterministic photon-photon interactions is a long-standing goal in optical science. Using an atomic ensemble inside a cavity, we demonstrate the mutual cross modulation of two continuous light beams at the level of individual photons

Nurturing a Disruptive Technology for Thermodynamic Metrology

September 12, 2014
Author(s)
Zeeshan Ahmed
This presenation lays out a case, based on economic and technologic considerations, that the present technologies for temperature and pressure measurement are ripe for disruption. We argue that a better use of research funds is to identify and nuture

PMML in Manufacturing Applications

September 12, 2014
Author(s)
Yung-Tsun T. Lee, Juyeon Lee
In manufacturing, an enormous amount of data, both real and simulation data, is being continuously generated. The appropriate information, if extracted from big data, could provide insights on increasing sustainability, productivity, flexibility, and

Recommended isolated-line profile for representing high-resolution spectroscopic transitions

September 11, 2014
Author(s)
Joseph T. Hodges, Jonathan Tennyson, P F. Bernath, Alain Campargue, A Csaszar, L Daumont, R R. Gamache, D Lisak, Olga Naumenko, Lawrence Rothman, Ha Tran, N Zobov, Boone Chris, L Gianfrani, Jean M. Hartmann
Recommendations of an IUPAC Task Group formed in 2011 on “Intensities and line shapes in high-resolution spectra of water isotopologues from Experiment and Theory" (Project No. 2011-022-2- 100) on line profiles of high-resolution rotational-vibrational

Degrees of Equivalence for Chemical Measurement Capabilities: Primary pH

September 10, 2014
Author(s)
David L. Duewer, Kenneth W. Pratt, Chainarong Cherdchu, Nongluck Tangpaisarnkul2 Nongluck Tangpaisarnkul2, Akiharu Hioki, Masaki Ohata, Petra Spitzer, Michal M?ri?ssy, Leo? Vysko?il
The Key Comparison (KC) studies of the Consultative Committee for Amount of Substance – Metrology in Chemistry (CCQM) help ensure the reliability of chemical and biochemical measurements relevant to international trade and environmental , health , and

Photon-number uncertainty in a superconducting transition-edge sensor beyond resolved-photon-number determination

September 10, 2014
Author(s)
Zachary H. Levine, Boris L. Glebov, Alan L. Migdall, Thomas Gerrits, Brice R. Calkins, Adriana E. Lita, Sae Woo Nam
As part of an effort to extend fundamental single-photon measurements into the macroscopic regime, we explore how best to assign photon-number uncertainties to output waveforms of a superconducting Transition Edge Sensor (TES) and how those assignments
Displaying 18001 - 18025 of 74178