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Alireza Panna, Mattias Kruskopf, Albert Rigosi, Martina Marzano, Dinesh K. Patel, Shamith Payagala, Dean G. Jarrett, David B. Newell, Randolph Elmquist
Yvonne A. Branden, Tina G. Butcher, Richard A. Harshman, Lisa Warfield, Gloria D. Lee, John W. Barton
The 104th Annual Meeting of the National Conference on Weights and Measures (NCWM) was held July 14 - 18, 2019, at the Hyatt Regency Milwaukee Hotel, Milwaukee, Wisconsin. The theme of the meeting was "Assuring Equity in the Marketplace: NIST and NCWM
Valeriy V. Yashchuk, Sergey Babin, Stefano Cabrini, Weilun Chao, Ulf Griesmann, Ian Lacey, Stefano Marchesini, Keiko Munechika, Carlos Pina-Hernandez, Allen L. Roginsky
Recently, a technique for calibrating the modulation transfer function (MTF) of a broad variety of metrology instrumentation has been demonstrated. This technique is based on test samples structured as one-dimensional binary pseudo-random (BPR) sequences
Takehiko Oe, Shamith U. Payagala, Dean G. Jarrett, Nobu-Hisa Kaneko
DC high resistance measurement capability has been evaluated using a NMIJ traveling dual source bridge between NIST and NMIJ. The NMIJ bridge determines the resistance ratio by measuring the voltage ratio using a digital multimeter, 3458A. Based on the
Dimitrios Georgakopoulos, Ilya F. Budovsky, Samuel Benz
We have extended the voltage range of the Josephson arbitrary waveform synthesizer from 1 mV down to 1 μV at frequencies from 60 Hz to 1 kHz to calibrate precision lock-in amplifiers. Experimental results show that the system's uncertainty is dominated by
Dean G. Jarrett, Shamith U. Payagala, Ryan P. Fitzgerald, Denis E. Bergeron, Jeffrey T. Cessna, Charles J. Waduwarage Perera, Neil M. Zimmerman
A system for the calibration of electrometers that measure currents from ionization chambers is described. The calibration system uses a 1 GΩ standard resistor in series with a stable voltage source to generate calibration currents from 1 pA to 20 nA
Takehiko Oe, Alireza R. Panna, Randolph E. Elmquist, Dean G. Jarrett, Yasuhiro Fukuyama, Nobu-Hisa Kaneko
We have fabricated 129 kΩ and 1 MΩ quantum Hall array devices using GaAs/AlGaAs heterostructures and their quantized Hall resistance plateaus were precisely evaluated with an accuracy of better than 5×10-8 based on NISTs quantized Hall resistance standard
Leon S. Chao, Rafael Marangoni, Frank C. Seifert, Darine El Haddad, Jon R. Pratt, David B. Newell, Stephan Schlamminger
After the recent redefinition of the International System of Units (SI), torque no longer needs to be traceable to a calibrated mass in a gravitational field suspended from a known lever arm and disseminated through a chain of torque transducers.An SI
Michael T. Postek, Andras Vladar, Dianne L. Poster, Atsushi Muto, Takeshi Sunaoshi
A new and exciting imaging technique being applied to thin films, nanocoatings, nanogels, and nanoparticle analysis is ultra-low accelerating voltage or ultra-low-landing-energy scanning electron microscopy (ULVSEM). Instrument conditions in this mode are
We describe the algorithmic foundations of an open-source numerical toolbox, written in the Octave language, for the creation of computer-generated binary and multi-level holograms used in interferometric form error measurements of complex aspheric and
Li Piin Sung, James E. Pickett, Olga Kuvshinnikova, Brett Ermi
The NIST (National Institutes of Standards and Technology) SPHERE (Simulated Photodegradation via High Energy Radiant Exposure) was used to obtain acceleration parameters, such as activation energies, for bisphenol A (BPA) polycarbonate (PC), poly(butylene
Roger V. Bostelman, YaShian Li-Baboud, Karl Van Wyk, Mili Shah
Exoskeletons are now being marketed by several manufacturers and yet there are currently no defined methods to measure the exoskeleton fit to the user. Proper exoskeleton fit to user impacts the safety of the human robot interaction. In this paper, we
Ling Wang, Balasubramanian Muralikrishnan, Octavio Icasio Hernandez, Craig M. Shakarji, Daniel S. Sawyer
Due to their accuracy, portability, and large working volume, laser trackers (LTs) are widely used for dimensional metrology in a variety of large-scale manufacturing and assembly operations. Their performance evaluation is a key concern for users
Carlos R. Beauchamp, Johanna Camara, Jennifer Carney, Steven J. Choquette, Kenneth D. Cole, Paul C. DeRose, David L. Duewer, Michael Epstein, Margaret C. Kline, Katrice Lippa, Enrico Lucon, Karen W. Phinney, Maria Polakoski, Antonio Possolo, Katherine E. Sharpless, John R. Sieber, Blaza Toman, Michael R. Winchester, Donald Windover
The National Institute of Standards and Technology (NIST), formerly the National Bureau of Standards, was established by the U.S. Congress in 1901 and charged with establishing a measurement foundation to facilitate U.S. and international commerce. NIST
The NIST Instrumented Charpy Test Suite is a set of standalone programs intended to allow anyone with appropriate hardware to perform and analyze instrumented Charpy impact tests. The software is provided in both raw code and executable formats with an
The JCGM documents have undermined the operational concept of uncertainty in measurement established by the GUM and restored the pre-GUM practice of stating possible error relative to the true value, supposedly to align with Bayesian interpretation. It is
David Sefcik, Lisa Warfield, Breyanna M. Blackwell
This document, "Guide for Labeling Consumer Packages by Weight, Volume, Count, or Measure (length, area, or thickness)," is based on the Uniform Packaging and Labeling Regulation (UPLR) in National Institute of Standards and Technology Handbook 130,
David R. Black, Marcus Mendenhall, Albert Henins, James Filliben, James Cline
The National Institute of Standards and Technology (NIST) certifies a suite of Standard Reference Materials (SRMs) to be used to evaluate specific aspects of instrument performance of both X-ray and neutron powder diffractometers. This report describes SRM
Due to the rapidly growing interest in energy harvesting from indoor ambient lighting for the powering of internet-of-things devices, accurate methods for proper measurements of the current vs voltage characteristics of light-harvesting solar photovoltaic
Shendong Shi, Balasubramanian Muralikrishnan, Vincent Lee, Daniel S. Sawyer, Octavio Icasio-Hern?ndez
Periodic performance evaluation is a critical issue for ensuring the reliability of data from terrestrial laser scanners (TLSs). With the recent introduction of the ASTM E3125-17 standard, there now exist standardized test procedures for this purpose
The measurement of heat transfer coefficients in microchannels is complicated due to the small sizes involved. Moreover, a heat transfer mechanism which is not usually considered, the axial conduction effect in the channel wall, must also be evaluated in
Frederic Overney, Nathan Flowers-Jacobs, Blaise Jeanneret, Alain Rufenacht, Anna Fox, Paul Dresselhaus, Samuel Benz
This paper presents a full characterization of a Dual Josephson Impedance Bridge (DJIB) at frequencies up to 80kHz by using the DJIB to compare the best available impedance standards that are (a) directly traceable to the quantum Hall effect, (b) used as
2019 was a big year for Metrology. The international system of units was revised on World Metrology Day, May 20th, that year [1]. What will 2020 bring? In this article we discuss five promising advances that we have on a watchlist for 2020. First, we
Alan L. Migdall, Evan Meyer-Scott, Christine Silberhorn
We review the rapid recent progress in single-photon sources based on multiplexing multiple probabilistic photon-creation events. Such multiplexing allows higher single-photon probabilities and lower contamination from higher-order photon states. We study