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The Moore M48 coordinate measuring machine (CMM) has provided NIST with unique and very flexible measurement capabilities for many years. The machines state of...
Refractometry of air is a central problem for interferometer-based dimensional measurements. Refractometry at the 10^{-9} level is only valid if air temperature...
The National Conference of Standards Laboratories International (NCSLI) 164 Education Liaison and Outreach Committee has coordinated the development of a...
A web-based application has been developed for shape-based searching for industrial components. The application is based on Flex, which is excellent at...
Thomas Gerrits, Scott Glancy, Tracy S. Clement, Brice R. Calkins, Adriana Lita, Aaron J. Miller, Alan Migdall, Aaron J. Miller, Sae Woo Nam, Richard Mirin, Emanuel Knill
We have generated and measured an approximation of an optical Schrödinger cat state by photon subtraction from squeezed vacuum. Figure 1 shows the experimental...
Thomas Gerrits, Burm Baek, Martin Stevens, Tracy S. Clement, Sae Woo Nam, Robert Hadfield, Ryan Bennink, Warren Grice, Sander N. Dorenbos, Tony Zijlstra, Teun Klapwijk, Val Zwiller
We present our experimental results obtained from a periodically poled KTP (pp-KTP) crystal designed to produce a pure squeezed vacuum near 1550 nm. A pure...
Peter E. Bradley, M.-H Lin, Ray Radebaugh, Marcia L. Huber, Y.C. Lee
Mixed-refrigerants offer greater minimum enthalpy difference for lower pressure ratios than pure gases such as Nitrogen or Neon. Two such mixtures, (5- and a 3...
Fern Y. Hunt, Christopher E. Dabrowski, Katherine Morrison
We report our work on the development of analytical and numerical methods that enable the detection of failure scenarios in distributed grid computing, cloud...
Models of cement hydration can take a number of mathematical and computational forms depending on the phenomena to be studied, the time regime to be spanned...
Jeffrey W. Bullard, Barbara Lothenbach, Paul E. Stutzman, Kenneth A. Snyder
We couple equilibrium thermodynamic calculations to a 3D microstructure model to simulate microstructure development during hydration of portland cement paste...
John T. McGraw, Peter C. Zimmer, Azzam Mansour, Dean C. Hines, Anthony B. Hull, Lisa Rossmann, Daniel C. Zirzow, Steven W. Brown, Gerald T. Fraser, Keith R. Lykke, Allan W. Smith, John T. Woodward IV, Christopher W. Stubbs
Earth's atmosphere represents a turbulent, turbid refractive element for every ground-based telescope. We describe the significantly enhanced and optimized...
We present Sigma ballots, a new type of ballot to be used in secure elections. Sigma ballots use the random order of candidates introduced by Pret a Voter...
Robert E. Chapman, Jeffrey T. Fong, David T. Butry, Douglas S. Thomas, James J. Filliben, Nathanael A. Heckert
This paper is built around ASTM E 2506, Standard Guide for Developing a Cost-Effective Risk Mitigation Plan for New and Existing Constructed Facilities. E 2506...
Jeffrey T. Fong, Stephen R. Gosselin, Pedro V. Marcal, James J. Filliben, Nathanael A. Heckert, Robert E. Chapman
This paper is a continuation of a recent ASME Conference paper entitled "Design of a Python-Based Plug-in for Bench-marking Probabilistic Fracture Mechanics...
Solomon I. Woods, Stephen M. Carr, Adriaan C. Carter, Timothy M. Jung, Simon G. Kaplan, Raju V. Datla
The Low Background Infrared (LBIR) facility has developed and tested the components of a new detector for calibration of infrared powers down to 1 pW, with 0.1%...
Chris Callison-Burch, Philipp Koehn, Christof Monz, Kay Peterson, Mark A. Przybocki, Omar F. Zaidan
This paper presents the results of the WMT10 and MetricsMATR10 shared tasks, which included a translation task, a system combination task, and an evaluation...
Michael T. Postek, Andras Vladar, William J. Keery, Michael R. Bishop, Benjamin Bunday, John Allgair
A new multipurpose instrument calibration standard has been released by NIST. This standard was developed to be used primarily for X and Y scale (or magnifi...
Recent efforts in test collection building have focused on scaling back the number of necessary relevance judgments and then scaling up the number of search...
In this paper, we propose a new approach to determining those five elastic constants with uncertainty bounds using the extra information obtainable from an over...
Pranav D. Shah, Jose D. Melo, Carlos A. Cimini, Jeffrey Fong
In developing composite material property database, three categories of data are needed. Category 1 consists of all raw test data with detailed information on...
Vladimir V. Marbukh, Kamran Sayrafian, Hamid Mahboubi, Ahmadreza Momeni, Amir G. Aghdam
This paper reports on work in progress on developing a unified co-evolutionary/pricing framework for Mobile Sensor Networks (MSN) self-organization. MSN self...
The six-meter Atacama Cosmology Telescope (ACT) in Chile was built to measure the cosmic microwave background (CMB) at arcminute angular scales. We present a...
The thermodynamic properties of a hydrofluoro-olefin (HFO) refrigerant are presented. The p-ρ-T behavior of high-purity (99.993 %) R1234ze(E) was measured from...
Steven W. Brown, Claire E. Cramer, Keith R. Lykke, Allan W. Smith, John T. Woodward IV, Peter Doherty, Emilio Falco, Christopher W. Stubbs
It is standard practice at many telescopes to take a series of flat field images prior to an observation run. Typically the flat field consists of a screen...
Katherine MacReynolds, Michael H. Francis, Douglas T. Tamura
A comparison of the planar, spherical and cylindrical near-field techniques was completed at the National Institute of Standards and Technology (NIST) for a Ku...
Timothy J. Burns, Steven P. Mates, Richard L. Rhorer, Eric P. Whitenton, Debasis Basak
New experimental data on AISI 1045 steel from the NIST pulse-heated Kolsky Bar Laboratory are presented. The material is shown to exhibit a nonequilibrium phase...
Randy Direen, David R. Novotny, Katherine MacReynolds
A near-field planar scanner is used to construct images of a nearby scene illuminated with millimeter-wave frequencies. We present our initial work in active...
An analytical model of the flow across a resistive flow path such as an orifice or pipe was applied to predict the inward leakage in an SCBA facepiece during a...
Santiago M. Ballester, Jose M. Corberan, Jose Gonzalvez-Macia, Piotr A. Domanski
Most of the current air-to-refrigerant heat exchanger models use the classic ε-NTU approach. These models do not account for longitudinal conduction neither in...
This paper presents a study of the air flow distribution through a residential air-conditioning heat exchanger. The test subject was a finned-tube, A-shaped...