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Chris Greer, David A. Wollman, Dean Prochaska, Paul A. Boynton, Jeffrey A. Mazer, Cuong Nguyen, Gerald FitzPatrick, Thomas L. Nelson, Galen H. Koepke, Allen R. Hefner Jr., Victoria Yan Pillitteri, Tanya L. Brewer, Nada T. Golmie, David H. Su, Allan C. Eustis, David Holmberg, Steven T. Bushby
Section 1305 of the Energy Independence and Security Act (EISA) of 2007 (Pub. L. 110-140) directs NIST ‘‘to coordinate the development of a framework that includes protocols and model standards for information management to achieve interoperability of
Natascha S. Milesi-Ferretti, David Shipley, Walter Zalis, Steven T. Bushby
This report summarizes the results of the Building Commissioning Research and Measurement Science Needs Webinar Workshop held on April 29, 2014, sponsored by the National Institute of Standards and Technology. This effort supports ongoing research into
This publication provides guidelines for evaluating mass calibrations and for establishing measurement assurance programs in precision mass calibration laboratories. The NIST Office of Weights and Measures (OWM) will use these guidelines when evaluating
This publication contains good laboratory practices, good measurement practices, and standard operating procedures to support the Basic Mass CD-ROM (SP 1001, SP 1001-S) and the Office of Weights and Measures Mass Metrology Seminar. It contains previously
This report documents the effort launched by the National Institute of Standards and Technology (NIST) to develop, organize, and convene a workshop on sustainability to promote the adoption and use of sustainable construction and manufacturing and guide
This report documents the effort launched by the National Institute of Standards and Technology (NIST) to develop, organize, and convene a workshop on sustainability to promote the adoption and use of sustainable construction and manufacturing and guide
Jin Chu Wu, Alvin F. Martin, Craig S. Greenberg, Raghu N. Kacker
The National Institute of Standards and Technology conducts an ongoing series of Speaker Recognition Evaluations (SRE). Recently a new paradigm was adopted to evaluate the performance of speaker recognition systems, in which three distributions of scores
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
Donald Windover, David L. Gil, Yasushi Azuma, Toshiyuki Fujimoto
X-ray reflectometry (XRR) provides researchers and manufacturers with a non-destructive way to determine thickness, roughness, and density of thin films deposited on smooth substrates. Due to the nested nature of equations modeling this phenomenon, the
Stephan Schlamminger, Ralph E. Pixley, Frithjof Nolting, Juergen Schurr, Ueli Straumann
In 2006, a final result of a measurement of the gravitational constant G performed by researchers at the University of Zuerich was published. A value of G=6.674 252(122)x 10^{-11} m^3 kg^-1 s^-2 was obtained after an experimental effort that lasted over
Nathan D. Orloff, Jan Obrzut, Christian J. Long, Thomas F. Lam, Pavel Kabos, David R. Novotny, James C. Booth, James A. Liddle
This software package was developed to analyze microwave cavity perturbation data in order to determine material dielectric properties. Example software is provided to assist with data acquisition and organization. Specifically, it is de-signed to be used
Much of the gasoline sold in the U.S. is blended with ethanol. Some components associated with underground storage tanks (UST) dispensing these blended fuels (namely the sumps containing submersible pumps) are experiencing rapid degradation due to
A short article about ice cream and frozen novelties to appear in the Office of Weights and Measures newsletter, "Weights and Measures Connection." This document sites sections of the NIST Handbook 130, "Uniform Laws and Regulations in the Areas of Legal
Aric W. Sanders, Anna E. Fox, Paul D. Dresselhaus, Alexandra Curtin
Superconducting electronics play an important role in quantum computation, ultra-low power electronics, voltage standards and magnetic sensors. Many of these applications rely on the microfabrication of superconducting circuits with multiple wiring layers
Although mass has historically been defined using an artifact standard, other means of realization are possible. One alternative approach employs a precision electromechanical balance, using the SI electrical units to derive a force used to measure the
Frank C. Seifert, Alireza R. Panna, Leon S. Chao, Yusi A. Cao, Darine El Haddad, Shisong Li, Stephan Schlamminger, Jon R. Pratt, Heeju Choi, Lori Haley
A watt balance is a promising instrument to realize the unit of mass at the kilogram level. The magnet system is one of the key elements of such an instrument. For the new watt balance currently under construction at the National Institute of Standards and
Darine El Haddad, Frank C. Seifert, Stephan Schlamminger, Leon S. Chao, David B. Newell, Jon R. Pratt
This paper gives a brief description of the laser interferometer system designed for the next generation watt balance experiment aimed to realize the unit of mass by direct link to Planck constant at the National Institute of Standards and Technology. The
Leon S. Chao, Stephan Schlamminger, Frank C. Seifert, Yusi A. Cao, Darine El Haddad, David B. Newell, Jon R. Pratt
The design of the new permanent-magnet driven watt balance and novel mechanical features will demonstrate the high-precision capabilities of a large complex mass measurement system with expected overall uncertainties on the order of 3 parts in 10^8.
Anthony J. Kearsley, William E. Wallace, Yutheeka Gadhyan
A stochastic regression method has been developed that decomposes chemical spectra into separate contributions from signal and from noise. The numerical results of regressing in this way on sample spectra are presented. The results suggest that this
Weights and Measures Inspector tests frozen chitterlingsto determine if the package contains the labeled net weight and if the purge is 20 % or less. Inspectors typically use Section 2.3. Basic Test Procedure and other portions of National Institute of
Ronald Colle, Ryan P. Fitzgerald, Lizbeth Laureano-Perez
A substantial 25 % error in the then known and accepted (102 5) year half-life of 209Po was reported on in 2007. This error was detected from decay data from two separate primary standardizations of a 209Po solution standard, which were performed
Esther Baumann, Jean-Daniel Deschenes, Fabrizio R. Giorgetta, William C. Swann, Ian R. Coddington, Nathan R. Newbury
Frequency-modulated continuous-wave laser detection and ranging (FMCW LADAR) measures the range to a surface through coherent detection of the backscattered light from a frequency-swept laser source. The ultimate limit to the range precision of FMCW LADAR
Darine El Haddad, Leon Chao, Frank Seifert, David B. Newell, Jon R. Pratt, Stephan Schlamminger
A redefinition of the International System of Units, the SI, is impending and could occur as early as 2017. After redefinition a means to realize the unit of mass is required. A watt balance is a promising device to realize the unit of mass at the kilogram
Jay H. Hendricks, Jacob E. Ricker, Patrick F. Egan, Gregory F. Strouse
Based on highly accurate optical interferometry and fundamental quantum calculations, researchers at the National Institute of Standards and Technology (NIST) in the US are developing an improved definition of the SI unit for pressure that will consign the