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Alain Rufenacht, Charles J. Burroughs, Paul D. Dresselhaus, Samuel P. Benz
The voltage error associated with the leakage current of programmable Josephson voltage standards (PJVS) is one of the largest contributions to the uncertainty in direct comparison of voltage standards. Due to the parallel biasing scheme of the PJVS and
Alireza Panna, Marlin E. Kraft, Albert Rigosi, George R. Jones Jr., Shamith Payagala, Mattias Kruskopf, Dean G. Jarrett, Randolph Elmquist
We describe recent scaling measurements to decade resistance levels based on both cryogenic and non-cryogenic current comparator bridges. National measurement institutes and the International Bureau of Weights and Measures derive traceability for the SI
Nicholas G. Paulter Jr., Donald R. Larson, Nicklaus F. Troje
The effect of motion through the portal of a walk-through metal detector (WTMD) has often been considered to contribute to the uncertainty in detecting threat objects being carried through the WTMD. However, typical metrological testing uses a robotic
Megan H. Cleveland, Justin M. Zook, Marc L. Salit, Peter M. Vallone
The National Institute of Standards and Technology (NIST) has developed reference materials for five human genomes. DNA aliquots are available for purchase and the data, analyses and high- confidence small variant and homozygous reference calls are freely
Kristen Greene, Shanee T. Dawkins, Yee-Yin Choong, Mary F. Theofanos, Sandra S. Prettyman, Susanne M. Furman, Michelle P. Steves
In public safety and homeland security, it is critical to understand technology users primary goals, the characteristics of the users, and the context in which they are operating. New and emerging technologies present opportunities and challenges for
Isotope ratio measurements have been conducted on a series of isotopically distinct pure CO2 gas samples using the technique of dual-inlet isotope ratio mass spectrometry (DI-IRMS). The influence of instrumental parameters, data normalization schemes on
The digital thread links disparate systems across the product lifecycle to support data curation and information cultivation and enable data-driven applications, e.g., digital twin. Realizing the digital thread requires the integration of semantically-rich
Over the past two years, the ODI has undertaken an ambitious effort to modernize the SRD Program. This report covers one aspect of this modernization effort, a comprehensive internal technical review of the 75 free data products currently carrying the SRD
Ndubuisi G. Orji, Yaw S. Obeng, Carlos Beitia, Supika Mashiro, James Moyne
This white paper provides an overview of virtual metrology (VM) and the benefits it can provide, with cost reduction (both capital expenditure and cycle time) being the primary benefit. The white paper also examines some of the issues preventing wider
John D. Wright, Aaron Johnson, Gina Kline, Michael R. Moldover
The rate of rise (RoR) method measures the time rate of change of the mass of gas in a collection volume as it is filled via a flow meter under test. The mass of gas is calculated from time-stamped pressure and temperature data gathered from the known
Samuel P. Benz, Joachim Fischer, Bernd Fellmuth, Christof Gaiser, Laurent Pitre, Fernando Sparasci, Lara Risegari, Roberto M. Gavioso, D M. Rippa, Bengt Hallstedt, Jifeng Qu, XiaoJuan Feng, Jianqiang Zhang, David R. White, L Gianfrani, A Castrillo, L Moretti, B Darquie, C Daussy, S Briaudeau, O Kozlova, J J. Segovia, M C. Martin, D del Campo, Michael R. Moldover
The International Committee for Weights and Measures (CIPM), at its meeting in October 2017 followed the recommendation of the Consultative Committee for Units (CCU) on the redefinition of the kilogram, ampere, kelvin and mole. For the redefinition of the
David B. Newell, Peter J. Mohr, Barry N. Taylor, Eite Tiesinga
Described in detail is the Committee on Data for Science and Technology (CODATA) special least- squares adjustment of the values of the fundamental constants carried out in the summer of 2017. Based on all relevant data available by 1 July 2017, its
Two hollow conical cavities have been developed and built for the National Institute of Standards and Technology (NIST) for use as radiometric brightness temperature sources, or blackbodies. According to Kirchoff's reciprocity relation, a good absorber is
Accurate number concentrations of particles in liquid media are needed to assess the quality of water, pharmaceuticals, and other liquids, yet there are limited reference materials or calibration services available with clear traceability to the
Jay H. Hendricks, Patrick F. Egan, Jacob E. Ricker, Jack A. Stone Jr., Kevin O. Douglass, Gregory F. Strouse
A team of NIST scientists is working to fundamentally change the way that the unit of pressure is realized and disseminated, an effort that will lead to the elimination of mercury barometer pressure standards.
Technical-performance standards operate within the homeland-security enterprise to save significant time and money while increasing safety to the public. This is illustrated in this white paper through the lens of the standards infrastructure that is being
Nathan Flowers-Jacobs, Alessio Pollarolo, Kevin Coakley, Adam C. Weis, Anna Fox, Horst Rogalla, Weston L. Tew, Samuel Benz
In preparation for the redefinition of the International System of Units (SI), five different electronic measurements of the Boltzmann constant have been performed using different Johnson noise thermometry (JNT) systems over the past seven years. In this
Dean G. Jarrett, Daniel Paseltiner, Shamith U. Payagala
We present the design, construction, calibration, and software development of a temperature monitoring system for resistance standards. The system supports 19 temperature probes. Over the range 295.15 K to 299.15 K (22 °C to 26 °C), we report an expanded
Jeanice M. Brown Thomas, David L. Duewer, Carolyn Q. Burdette, Lorna T. Sniegoski, James H. Yen
Standard Reference Material (SRM) 968f is intended for use in validating methods for determining fat soluble vitamins in human serum and plasma and value assigning in house produced control materials analyzed using those methods. A unit of SRM 968f
This guide addresses apparel, including childrens apparel, and household textiles. It does not include other textiles, such as sleeping bags, tents, sporting goods, or other non-household products that contain or are made from textile materials.
This guide addresses apparel, including childrens apparel, and household textiles. It does not include other textiles, such as sleeping bags, tents, sporting goods, or other non-household products that contain or are made from textile materials.
Conrad E. Bock, Raphael Barbau, Ion Matei, Mehdi Dadfarnia
Computer-interpretable representations of system structure and behavior are at the center of developing today's complex systems. Systems engineers create and review these representations using graphical modeling languages that capture requirements, designs
Julia Scherschligt, James A. Fedchak, Daniel Barker, Stephen Eckel, Nikolai Klimov, Constantinos Makrides, Eite Tiesinga
The National Institute of Standards and Technology has recently begun a program to develop a primary pressure standard that is based on ultra-cold atoms, covering a pressure range of 1 × 10-6 Pa to 1 × 10-10 Pa and possibly lower. These pressures