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Quantity Calculus, Fundamental Constants, and SI Units
No full textA revised International System of Units (SI) is expected to be established by the 26th General Conference on Weights and Measures when it convenes in November 2018 and to be put into practice starting on 20 May 2019, World Metrology Day. In consequence, the article published in this journal in 2011, “The Current SI Seen from the Perspective of the Proposed New SI,” is updated in this paper, which provides an opportunity to again demonstrate the usefulness of the quantity calculus in dealing with quantities and units. The quantity calculus and the seven defining constants of the current and revised SI are reviewed, and expressions for the seven current and revised SI base units are given. Relationships between the magnitudes of revised and current SI units and expressions for the numerical values of current SI defining constants expressed in revised SI units are also obtained using the quantity calculus
Realizations of the Triple Point of Sulfur Hexafluoride in Transportable and Refillable Cells
No full textThe Minamata Convention on Mercury has created a near-term need to develop alternative fixed points to replace the mercury triple point (Hg TP) for calibration of standard platinum resistance thermometers (SPRTs) on the International Temperature Scale of 1990 (ITS-90). The sulfur hexafluoride (SF6) TP is a good candidate to provide adequate "drop-in compatible" replacements for the lowest costs. We report our first results of SF6 TP realizations performed at the National Institute of Standards and Technology (NIST) using a new series of transportable and refillable triple-point cells. The melting curves are presented at various melted fractions F and compared to evaluate the reproducibility and overall uncertainty for the realizations. We obtained a TP temperature of 223.55587(33) K at F= 50 % and 223.55607(35) K at F= 100 % as a weighted average of realizations using two adiabatic-type cells and two immersion-type cells. (Unless otherwise stated, uncertainties are standard uncertainties corresponding to a 68 % confidence level.) Temperatures were derived using a combination of five different SPRTs as calibrated at NIST on the ITS-90. The data were evaluated over a region of the melting plateau for melted fraction F between 30 % <= F <= 80 % with a 0.2 mK wide melting range. The results from the immersion-type cells were used to derive an experimental value for the SF6 TP static head correction of -11.6(1.7) mK/m. This value implies an initial slope of the pressure-temperature (p-T) equilibrium melting line of 1.55 MPa/K, which is in agreement with the value predicted via the Clapeyron equation. The uncertainties of these initial SF6 TP realizations are limited by uncertainty in the realization of the ITS-90 (0.25 mK) and, to a lesser extent, static pressure head effects and chemical impurities
Gain Calibration of Current-to-Voltage Converters
No full textCurrent-to-voltage converters are used in many photometric and radiometric applications. The calibration of current-to-voltage converters at a few input currents is not always sufficient to understand the linearity and the bias of a device. Many devices have structure deviating from a linear response over the operating range of a gain setting. Measurement services that rely on these devices now have decreased uncertainties to a level that requires quantifying the uncertainties and understanding how they propagate. The National Institute of Standards and Technology has developed a system to calibrate the current-to-voltage conversion factor or "gain" and offset of these devices for direct current photocurrents. The equipment used for the calibration is described here, and the results and uncertainties are discussed
Industrial Wireless End-to-End Measurements and Impacts in a Gas-Sensing Scenario
No full textIndustrial wireless is a potential networking solution in many scenarios due to its flexibility and ease of communications in harsh environments. Industrial wireless in gas-sensing and air-quality monitoring applications is essential when wired communications cannot perform the task safely and effectively. A major example of such environments is confined spaces where attaching mobile gas sensors with wires is a major concern for safety and cannot be deployed in some cases. At the National Institute of Standards and Technology (NIST), we developed an end-to-end characterization method for industrial wireless networks. We employed this characterization method to study the end-to-end error and delay performance for a confined-space gas-sensing scenario. We have built the scenario using the NIST industrial wireless test bed, which includes ISA100.11a wireless devices, a channel emulator, and a high-performance programmable logic controller (PLC), where the physical process is simulated. In this work, we studied the effects of the size of the confined space, the relaying, input signal rate, and the impact of the existing workers in the confined space
Dispersion and Burning Behavior of Hydrogen Released in a Full-Scale Residential Garage in the Presence and Absence of Conventional Automobiles _�� Supplemental Video Materials
No full textThe supplemental materials reported here provide standard high-definition (HD), high-speed, and infrared videos of the 13 full-scale hydrogen dispersion and burning experiments on which Ref. [1] is based. References [1] and [2] provide detailed descriptions of the experimental conditions under which these videos were taken. The videos show different burning dynamics of various hydrogen/air mixtures in the presence and absence of vehicles parked inside the garage. The test identification (ID) numbers associated with the filenames of the data folders correspond to those in Table 1 of Ref. [1]. The number, types, and locations of the videos varies from test-to-test
Robert E. Chapman
No full textROBERT E. CHAPMAN
NBS/NIST: 1975–2016
INDUCTED: 2018
B: 1947, Washington, DC
EDUCATION:
McDaniel College, BA (Mathematics), 1972
Indiana University (Bloomington), MA (Mathematics/Statistics), 1974
George Washington University, PhD (Economics), 1988
CITATION: For advancing the use of economics and mathematics to facilitate cost effective resource decisions, improving life safety, security, and interoperability within the built environment.
POSITIONS HELD AT NBS/NIST:
Operations Research Analyst, Building Economics and Regulatory Technology Division, Center for Building Technology, National Engineering Laboratory, 1975-1980
Mathematician, Center for Applied Mathematics, National Engineering Laboratory, 1980-1988
Acting Director, Office of Technology Commercialization, 1988-1990
Economist, Office of Quality Programs, Office of the Director, 1990-1993
Supervisory Industrial Economist, Office of Quality Programs, Office of the Director, 1993-1995
Economist, Office of Applied Economics, Building and Fire Research Laboratory, 1995-2007
Chief, Office of Applied Economics, Engineering Laboratory, 2007-2016
HONORS:
NBS Bronze Medal (1982)
ASTM International Awards: Award of Appreciation (2006); E. George Stern Award of Excellence (2012); Award of Excellence (2016); and Award of Appreciation (2016)
Construction Industry Institute (CII), Distinguished Service Award (2015)
MEMBERSHIPS:
ASTM International and ASTM Subcommittee E06.81 on Building Economics (1995-2016), Co-Chair (2007-2016) and Secretary and Task Chair for Techniques (1996-2007)
Construction Industry Institute (CII) (1995-2016), founding member CII’s Benchmarking & Metrics Committee (1996-2016)
PUBLICATIONS:
More than 90 publications including:
Chapman, R.E., A Cost-Conscious Guide to Fire Safety in Health Care Facilities, NBS IR 82-2600 (1982)
Chapman, R.E., Benefit-Cost Analysis for the Modernization and Associated Restructuring of the National Weather Service, NIST IR 4867 (1992)
Chapman, R.E., Benefits and Costs of Research: A Case Study of Construction Systems Integration and Automation Technologies in Industrial Facilities, NIST IR 6501 (2000); led to Gallaher, M.P., et al., Cost Analysis of Inadequate Interoperability in the U.S. Capital Facilities Industry, NIST GCR 04-867 (2004)
Kasi, M. and Chapman, R.E., Benefits of Using ASTM Building Economics Standards for the Design, Construction, and Operation of Constructed Facilities, NIST SP 1098 (2012); led to ASTM Standards on Building Economics 7th Edition, ASTM International (2012)
Chapman, R.E. and Goodkind, M.N., Eds., Ideas to Impact: How Building Economic Standards Keep You on Track, STP 1586, ASTM International (2014)
Chapman, R.E., "Community Resilience Economic Decision Guide for Buildings and Infrastructure Systems -An Overview," in Ayyub, B.M., Chapman, R.E., Galloway, G.E., Wright, R.N., Eds., Economics of Community Disaster Resilience Workshop Proceedings, NIST SP 1600, 3-15 (2016
A. Hunter Fanney
No full textA. HUNTER FANNEY
NBS/NIST: 1977–2017
INDUCTED: 2018
B: 1952, Portsmouth, Virginia
EDUCATION:
Virginia Polytechnic Institute and State University (VPI),
BS (Mechanical Engineering), 1974
VPI, MS (Mechanical Engineering), 1975
VPI, PhD (Mechanical Engineering), 1981
CITATION:
For positioning NIST as a leader in research supporting high-performance, sustainable buildings, and for advancing measurement science in the areas of building thermal envelope, appliance, and solar energy systems performance.
POSITIONS HELD AT NBS/NIST:
Mechanical Engineer, Solar Equipment Group, Building Equipment Division, Center for Building Technology (CBT), National Engineering Laboratory (NEL), 1977-1984
Leader, Heat Transfer Group, CBT/NEL and Building and Fire Research Laboratory, 1984-2007
Program Analyst, Director’s Office, 1991-1992
Chief, Energy and Environment Division, Engineering Laboratory, 2007-2014
Senior Research Scientist, Engineering Laboratory, 2014-2017
Guest Researcher, Engineering Laboratory, 2017-present
HONORS:
NIST Bronze Medal (1988 and 2007)
Federal Laboratory Consortium Award for Excellence in Technology Transfer (1997)
DoC/NIST Federal Engineer of the Year Award, National Society of Professional Engineers (1998)
Maryland Governor’s Citation (Paris Glendening) (1999)
ASME Fellow (1992) and John I. Yellott Award (2006)
U.S. Department of Commerce Silver Medal (2009)
U.S. Green Building Council Wintergreen Award (2012)
NIST Jacob Rabinow Applied Research Award (2016)
MEMBERSHIPS:
Co-chair of National Science and Technology Council Subcommittee on Buildings Technology R&D
U.S. Green Building Council; American Society of Mechanical Engineers; ASTM International; American Society of Heating Refrigerating and Air-Conditioning Engineers
U.S.-China Clean Energy Research Center Buildings Energy Efficiency Executive Committee
U.S. Department of Energy Solar Decathlon Engineering Evaluation Team
PUBLICATIONS:
More than 80 publications including:
Liu, S.T. and Fanney, A.H., "Comparison of Experimental and Computer-Predicted Performance for Six Solar Domestic Hot Water Systems", ASHRAE Transactions, Vol. 86, No. 1, 823-835 (1980)
Fanney, A.H. and Klein, S.A., "Thermal Performance Comparisons for Solar Hot Water Systems Subjected to Various Collector and Heat Exchanger Flow Rates", Solar Energy, Vol. 40, No. 1, 1-11 (1988)
Fanney, A.H. and Dougherty, B.P., "Photovoltaic Solar Water Heating System", ASME Journal of Solar Energy Engineering, Vol. 119, 126-133 (May 1997)
Fanney, A.H., Davis, M.W., Dougherty, B.P., et al., "Comparison of Photovoltaic Module Performance Measurements", ASME Journal of Solar Energy Engineering, Vol. 128, 152-159 (2006)
Fanney, A.H., et. al, "Net-zero and Beyond! Design and Performance of NIST’s Net-Zero Energy Residential Test Facility", Energy and Buildings, Vol. 101, 95-109 (2015
Concept to Commercialization of an Artifact for Evaluating Three-Dimensional Imaging Systems per ASTM E3125-17
No full textSummary:
• The relative-range error test is one of several tests described in the ASTM E3125-2017 standard for performance evaluation of spherical coordinate three-dimensional (3D) imaging systems such as terrestrial laser scanners (TLS). We designed a new artifact, called the plate-sphere target, that allows the realization of the relative-range error tests quickly and efficiently without the need for alignment at each position of the test.
• Use of a simple planar/plate target requires careful alignment of the target at each position of the relative-range error test, which is labor-intensive and time-consuming. This new artifact significantly reduces the time required to perform the test, from a matter of about 2 h to less than 30 min while resulting in similar test uncertainty values.
• The plate-sphere target was conceived and initially developed at the National Institute of Standards and Technology (NIST), improved based on feedback from collaborators at the National Research Council (NRC) of Canada and TLS manufacturers, and commercialized by Bal-tec Inc.
• This new artifact will save users and manufacturers of TLSs considerable time and money
Implementation of an Effective Bond Energy Formalism in the Multicomponent Calphad Approach
No full textMost models currently used for complex phases in the calculation of phase diagrams (Calphad) method are based on the compound energy formalism. The way this formalism is presently used, however, is prone to poor extrapolation behavior in higher-order systems, especially when treating phases with complex crystal structures. In this paper, a partition of the Gibbs energy into effective bond energies, without changing its configurational entropy expression, is proposed, thereby remarkably improving the extrapolation behavior. The proposed model allows the use of as many sublattices as there are occupied Wyckoff sites and has great potential for reducing the number of necessary parameters, thus allowing shorter computational time. Examples for face centered cubic (fcc) ordering and the sigma phase are given
ITL-Cybersecurity_2018-02-07_audio
No full textITL Oral history interview of Dennis Branstad, Miles Smid, and Stuart Katzke all of whom were principle players in the establishment and implementation of the NBS/NIST program in data encryption and cyber security