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NIST Authors in Bold

Displaying 17676 - 17700 of 74070

Frequency-Comb-Based Remote Sensing of Greenhouse Gases over Kilometer Air Paths

October 29, 2014
Author(s)
Greg B. Rieker, Fabrizio R. Giorgetta, William C. Swann, Jonathan Kofler, Alexander M. Zolot, Laura C. Sinclair, Esther Baumann, Christopher L. Cromer, G. Petron, Colm Sweeney, P P. Tans, Ian R. Coddington, Nathan R. Newbury
We demonstrate frequency comb tooth-by-tooth measurements of atmospheric gas absorption across a 2-km, turbulent, open-air path through coherent dual-comb spectroscopy. High accuracy, high signal-to-noise transmission spectra are acquired spanning 5990 to

Optimal Deployment of Pico Base Stations in LTE-Advanced Heterogeneous Networks

October 29, 2014
Author(s)
Sungseob Lee, SuKyoung Lee, Kim KyungSoo, David W. Griffith, Nada T. Golmie
As data traffic demand in cellular networks grows exponentially, operators need to add new cell sites to keep up; unfortunately, it is costly to build and operate macrocells. Moreover, it may not be possible to obtain the needed approvals for additional

Release of NIST SP 800-147B, BIOS Protection Guidelines for Servers

October 29, 2014
Author(s)
Andrew R. Regenscheid, Larry Feldman, Gregory A. Witte
Modern computers rely on fundamental system firmware, commonly known as the Basic Input/Output System (BIOS), to enable system components to communicate and work together. The BIOS is typically developed by both original equipment manufacturers (OEMs) and

Carbon Monoxide Exposure from Portable Generators

October 28, 2014
Author(s)
Steven J. Emmerich, Andrew K. Persily, Liangzhu Wang
Serious concerns exist about the hazard of acute residential carbon monoxide (CO) exposures from portable gasoline-powered generators, which can result in death or serious adverse health effects. As of April 23, 2013 and as shown in Figure 1, the U.S

Extended and Revised Analysis of Singly Ionized Tin: Sn II

October 28, 2014
Author(s)
K. Haris, Alexander Kramida, A. Tauheed
The electronic structure of singly ionized tin (Sn II) is partly a one-electron and partly a three-electron system with ground configuration 5s25p. The excited configurations are of the type 5s2nℓ in the one-electron part, and 5s5p2, 5p3 and 5s5pnℓ (nℓ =

Nanoscale Structural Heterogeneity in Ni-rich Half-Heusler TiNiSn

October 28, 2014
Author(s)
Jason E. Douglas, Philip A. Chater, Craig Brown, Tresa M. Pollock, Ram Seshadri
The structural implications of excess Ni in the TiNiSn half-Heusler compound are examined through a combination of synchrotron x-ray and neutron scattering studies, in conjunction with first principles density functional theory calculations on supercells

A Cross-Benchmarking and Validation Initiative for Tokamak 3D Equilibrium Calculations

October 27, 2014
Author(s)
Geoffrey B. McFadden, Allan Reiman, Antoine Cerfon, E. Lazarus, S. Lazerson
We are pursuing a cross-benchmarking and validation initiative for tokamak 3D equilibrium calculations, with 11 codes participating: the linearized tokamak equilibrium codes IPEC and MARS-F,the time-dependent extended MHD codes M3D-C1, M3D, and NIMROD, the

Nanoparticle size determination using optical microscopes

October 27, 2014
Author(s)
Ravikiran Attota, Richard J. Kasica, Premsagar P. Kavuri, Hyeong G. Kang, Lei Chen
We present a simple method for size determination of nanoparticles using conventional optical microscopes. The method, called through-focus scanning optical microscopy (TSOM), makes use of the four-dimensional optical information collected at different

Spatial Computations over Terabyte-Sized Images on Hadoop Platforms

October 27, 2014
Author(s)
Peter Bajcsy, Antoine Vandecreme, Mary C. Brady, Phuong Nguyen
Our objective is to lower the barrier of executing spatial image computations in a computer cluster/cloud environment instead of in a desktop/laptop computing environment. We research two related problems encountered during an execution of spatial

The Leucine-Rich Amelogenin Peptide (LRAP) is a Partially Structured Monomer in Solution

October 25, 2014
Author(s)
Barbara J. Tarasevich, John S. Philo, Nasib Karl Mulof, Susan T. Krueger, Garry W. Buchko, Genyao Lin, Wendy J. Shaw
Amelogenin proteins are critical to the formation of enamel in teeth and may have roles in promoting nucleation, controlling growth, and regulating microstructures of the intricately woven hydroxyapatite (HAP). Leucine-rich amelogenin peptide (LRAP) is a

Path degeneracy and EXAFS analysis of disordered materials

October 24, 2014
Author(s)
Bruce D. Ravel
The analysis of EXAFS data measured on a material with a disordered local configuration environment around the absorbing atom can be challenging due to the proliferation of photoelectron scattering paths that must be considered in the analysis. In the case

3D Monte Carlo modeling of the SEM: Are there applications to photomask metrology?

October 23, 2014
Author(s)
John S. Villarrubia, Andras Vladar, Michael T. Postek
The ability to model the effect of fields due to charges trapped in insulators with floating conductors has been added to JMONSEL (Java Monte Carlo simulator for Secondary Electrons) and applied to a simple photomask metal on glass geometry. These

An Additive Manufacturing Test Artifact

October 23, 2014
Author(s)
Shawn P. Moylan, John A. Slotwinski, A L. Cooke, Kevin K. Jurrens, M A. Donmez
We propose a test artifact, intended for standardization, for the purpose of evaluating the performance of additive manufacturing (AM) systems. A thorough analysis of previously proposed AM test artifacts as well as experience with machining test artifacts

High-Fidelity, Weak-Light Polarization Gate Using Room-Temperature Atomic Vapor

October 23, 2014
Author(s)
Lu Deng, Runbing Li, Chengjie Zhu, Edward W. Hagley
Using a polarization-selective-Kerr-phase-shift technique we demonstrate an all-optical polarization gate in an atomic gain medium with the control-field intensity equivalent to 20 photons of 10 nanoseconds propagating in a 5 μm mode diameter photonic

On Systemic Risk in the Cloud Computing Model

October 23, 2014
Author(s)
Vladimir V. Marbukh
The major benefits of the emerging cloud computing infrastructure include elimination of the fixed cost and reduction in the marginal cost for the users due to the economy of scale and dynamic resource sharing. This paper argues that these unquestionable

Structure and Stability of Phospholipid Bilayers Hydrated by a Room-Temperature Ionic Liquid/Water Solution: a Neutron Reflectometry Study

October 23, 2014
Author(s)
Antonio Benedetto, Frank Heinrich, Miguel A. Gonzalez, Giovanna Fragneto, Erik Watkins, Pietro Ballone
Neutron reflectometry measurements (NR) have been carried out to probe the structure and stability of two model bio-membranes consisting of POPC and DMPC phospholipid bilayers hydrated by water solutions of two prototypical room-temperature ionic liquids
Displaying 17676 - 17700 of 74070