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Displaying 10926 - 10950 of 53164

The Effect of Sampling Strategy on Inferred Measures

July 6, 2014
Author(s)
Ellen M. Voorhees
Using the inferred measures framework is a popular choice for constructing test collections when the target document set is too large for pooling to be a viable option. Within the framework, different amounts of assessing effort is placed on different

Extreme ultraviolet spectra and analysis of ?n=0 transitions in highly charged barium

July 4, 2014
Author(s)
Joseph Reader, John D. Gillaspy, Dmitry D. Osin, Yuri Ralchenko
Extreme ultraviolet spectra of highly charged barium atoms were produced with an electron beam ion trap (EBIT) and recorded with a flat-field grazing-incidence spectrometer. The spectra were measured in the wavelength range 4 nm to 24 nm with the beam

Approximate Matching: Definition and Terminology

July 2, 2014
Author(s)
Frank Breitinger, Barbara Guttman, Michael McCarrin, Vassil Roussev, Douglas R. White
This document provides a definition of and terminology for approximate matching. Approximate matching is a promising technology designed to identify similarities between two digital artifacts. It is used to find objects that resemble each other or to find

Imaging the p-n junction in a gallium nitride nanowire with a scanning microwave microscope

July 2, 2014
Author(s)
Atif A. Imtiaz, Thomas M. Wallis, Joel C. Weber, Kevin J. Coakley, Matthew D. Brubaker, Paul T. Blanchard, Kristine A. Bertness, Norman A. Sanford
We used a broadband, atomic-force-microscope-based, scanning microwave microscope (AFM-SMM) to probe the axial dependence of the depletion in a GaN nanowire (NW) p-n junction structure. The NWs were c-axis oriented and grown by molecular beam epitaxy. The

On the limits of spin-exchange optical pumping of 3He

July 2, 2014
Author(s)
Thomas R. Gentile, T G. Walker, E Babcock, Qiang NMN Ye, Wangchun Chen
Using diode bar lasers spectrally narrowed with chirped volume holographic gratings (VHGs), we have obtained an improvement in the 3He polarization achievable by spin-exchange optical pumping (SEOP). As compared to our past results with lasers narrowed

Quantification of Methane Emissions From Street Level Data

July 2, 2014
Author(s)
Kuldeep R. Prasad
Kuldeep Prasad(1), Brian Lamb(2), Maria Obiminda Cambaliza(3), Tegan Lavoie(3), Olivia E Salmon(3), Paul Shepson(3), Thomas Lauvaux(4), Ken Davis(4), and James R. Whetstone(1) (1) National Institute of Standards and Technology, Gaithersburg, MD. (2)

Quantitative Infrared Imaging of Impinging Turbulent Buoyant Diffusion Flames

July 2, 2014
Author(s)
Randall J. McDermott, Ashish Newale, Brent Rankin, Harshad Lalit, Jay P. Gore
Radiation from buoyant diffusion flames with and without impingement on a flat plate is studied using a unique quantitative comparison of measured and simulated images. The coupling between the stagnation boundary layer and upstream buoyant shear layer

The red color in 19th century Thai glass studied by X-ray and optical spectroscopy

July 2, 2014
Author(s)
Bruce D. Ravel, Wantana Klysubun, G. Lawrence Carr, Christoph Hauzenberger
The Temple of the Emerald Buddha in Bangkok, Thailand is noted for its glass mosaic decorations on exterior walls and statuary. The original mosaic artwork dates to the early 19th century and is composed of variously-colored, mirrored glass pieces. In this

Accurate Fast Capacitance Measurements for Reliable Device Characterization

July 1, 2014
Author(s)
Pragya R. Shrestha, Kin P. Cheung, Jason P. Campbell, Jason T. Ryan, Helmut Baumgart
As device dimensions continue to scale, transient phenomena are becoming increasingly more important to understand for both performance and reliability considerations. Recently, fast capacitances versus voltage (CV) measurements have been gaining attention

Angle-resolved diffuse reflectance and transmittance

July 1, 2014
Author(s)
Thomas A. Germer, J C. Stover, Sven Schroeder
This chapter will cover the topic of bidirectional reflectance distribution function [BRDF] measurements. These measurements, like the diffuse reflectance and transmittance measurements described in the previous chapter, cover the gamut from highly

Determination of the Planck constant at the National Institute of Standards and Technology

July 1, 2014
Author(s)
Stephan Schlamminger, Darine El Haddad, Frank C. Seifert, Leon S. Chao, David B. Newell, Ruimin Liu, Richard L. Steiner, Jon R. Pratt
In 2013, a new measurement of the Planck constant h was performed using a watt balance at the National Institute of Standards and Technology (NIST). The value is h=6.626 069 79(30) x 10^{-34} J s. The relative standard uncertainty of this determination is

Dispersive Methods

July 1, 2014
Author(s)
Arnold A. Gaertner, Howard W. Yoon, Thomas A. Germer
Chapter 3 will discuss dispersive means of obtaining spectral resolution in spectrophotometry. These methods are used to spatially disperse or separate the various wavelengths of optical electromagnetic radiation to enable analysis of material properties

EXPERIMENTAL STUDY OF RC ASSEMBLIES UNDER A COLUMN REMOVAL SCENARIO

July 1, 2014
Author(s)
Hai S. Lew, Yihai Bao, Santiago Pujol, Mete Sozen
This paper presents an experimental study of two full-scale reinforced concrete (R/C) beam-column assemblies under a column removal scenario. The assemblies represent portions of the exterior moment-resisting frames of two ten-story R/C frame buildings

Final report of the key comparison CCQM-K98: Pb isotope amount ratios in bronze

July 1, 2014
Author(s)
Jochen Vogl, Yong-Hyeon Yim, Kyoung-Seok Lee, Heidi Goenaga-Infante, Dmitriy Malinowskiy, Tongxiang Ren, Jun Wang, Robert D. Vocke Jr., Karen E. Murphy, Naoko Nonose, Olaf Rienitz, Janine Noordmann, Teemu Naeykki, Timo Sara-Aho, Bet?l Ari, Oktay Cankur
Isotope amount ratios are proving useful in an ever increasing array of applications that range from studies unravelling transport processes, to pinpointing the provenance of specific samples as well as trace element quantification by using isotope

Influence of morphology on current-voltage behavior of GaN nanowires

July 1, 2014
Author(s)
Paul T. Blanchard, Kristine A. Bertness, Matthew D. Brubaker, Todd E. Harvey, Aric W. Sanders, Norman A. Sanford
We demonstrate the effect that the different morphologies of MBE-grown GaN nanowires (NWs) can have upon current-voltage (I-V) behavior. Two main aspects of NW morphology were investigated. The first aspect was the NW diameter, dNW. For single-crystal Si

Microresonator frequency comb optical clock

July 1, 2014
Author(s)
Scott B. Papp, Katja M. Beha, Pascal P. Del'Haye, Franklyn J. Quinlan, Hansuek Lee, Kerry J. Vahala, Scott A. Diddams
Optical frequency combs enable measurement precision at the 20th digit, and measurement accuracy entirely commensurate with their reference oscillator. A new direction in experiments is the creation of ultracompact frequency combs by way of nonlinear

New Developments in the NIST Infrared Optical Properties of Materials Program

July 1, 2014
Author(s)
Leonard M. Hanssen, Sergey Mekhontsev, Jinan Zeng, John H. Burnett
The Infrared Optical Properties of Materials program in the Sensor Science Division at the National Institute of Standards and Technology (NIST) continues to upgrade its capabilities to provide comprehensive coverage of measurable infrared optical
Displaying 10926 - 10950 of 53164