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Metrology

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Displaying 126 - 150 of 2728

Mechanism of Action, Potency and Efficacy: Considerations for Cell and Gene Therapies

April 1, 2024
Author(s)
Carl Simon Jr., Anne L. Plant, Catherine Zander, Erich Bozenhardt, Christina Celluzzi, David Dobnik, Melanie Grant, John Hughes, Uma Lakshmipathy, Kok-Seong Lim, Laura Montgomery, Hesham Nawar, Thiana Nebel, Linda Peltier, James Sherley, Rouzbeh Taghizadeh, Eddie Tan, Sandrine Vessillier
One of the most challenging aspects of cell and gene therapy products (CGTPs) is defining mechanism of action (MOA), potency and efficacy of the product. This perspective examines these concepts and presents helpful ways to think about them through the

Comparison of a 1 nF Capacitor with a 1 kO Resistor Using a Digital Impedance Bridge

March 27, 2024
Author(s)
Yicheng Wang, Stephan Schlamminger, Dean G. Jarrett, Alireza Panna, Andrew D. Koffman
This paper reports our effort to improve a digital impedance bridge. The limit of the bridge resolution and stability is less than 3 parts in 10^9 for the nominal 1:1 impedance comparison of two 100 pF capacitors. The type-A uncertainty for comparison of a

Certification Approaches for Weigh-In-Motion Systems in Law Enforcement Applications

March 26, 2024
Author(s)
Katrice Lippa, Jan Konijnenburg, Loren Minnich, Tanvi Pandya, James Willis
Every day, overweight and excessively heavy vehicles cause damage to roads, bridges, and other vehicle-based infrastructure. To protect this vital transportation infrastructure for the U.S., states have imposed weight limits for commercial and fleet

Excited-Band Coherent Delocalization for Improved Optical Lattice Clock Performance

March 24, 2024
Author(s)
Jacob Siegel, Andrew Ludlow, Youssef Hassan, Kyle Beloy, Tanner Grogan, Chun-Chia Chen
We implement coherent delocalization as a tool for improving the two primary metrics of atomic clock performance: systematic uncertainty and instability. By decreasing atomic density with co- herent delocalization, we suppress cold-collision shifts and two

Discover STEM Education Resources

March 6, 2024
Author(s)
Cara O'Malley, Elizabeth Benham
The National Institute of Standards & Technology (NIST) invites educators to discover STEM resources on the NIST Educational STEM Resource (NEST-R) registry! Published by NIST scientists, engineers, & staff, NEST-R content is free & publicly available. It

A Common Data Dictionary and Common Data Model for Additive Manufacturing

February 16, 2024
Author(s)
Alexander Kuan, Kareem Aggour, Shengyen Li, Yan Lu, Luke Mohr, Alex Kitt, Hunter Macdonald
Additive manufacturing (AM) leverages emerging technologies and well-adopted processes to produce near-net-shape products. The advancement of AM technology requires data management tools to collect, store and share information through the product

Practical realisation of the kelvin by Johnson noise thermometry

February 15, 2024
Author(s)
Horst Rogalla, D Rod White, Jifeng Qu, Samuel P. Benz, Christof Gaiser, Weston L. Tew, Nathan Flowers-Jacobs, Kevin J. Coakley, Alessio Polarollo, Chiharu Urano
Johnson noise thermometry (JNT) is a purely electronic method of thermodynamic thermometry. In primary JNT, the temperature is inferred from a comparison of the Johnson noise voltage of a resistor at the unknown temperature with a pseudo-random noise

Application of Electrical Standards to Torque Realization: A Device to Measure up to 1Nm

February 14, 2024
Author(s)
Zane Comden, Stephan Schlamminger, Frank Seifert, David B. Newell, Leon Chao
This paper describes the next generation prototype of the Electronic NIST Torque Realizer (ENTR) project. The first prototype version (ENTR-v1) has been able to realize low-range torques (on the order of 1×10-3 Nm) to uncertainties of less than 1000 parts

Multi-kilowatt cw laser power measurement comparison between NMI standards

February 14, 2024
Author(s)
Kyle Rogers, Paul A. Williams, John H. Lehman, Marco Lopez, Marcel Pastuschek, Holger Lecher, Stefan Kueck
We present here the first comparison between National Metrology Institutes (NMIs) of high accuracy continuous wave (cw) optical power measurements in the kilowatt regime. The National Institute of Standards and Technology (NIST) performed measurements with

Measurement of 100 nm Monodisperse Particles by Four Accurate Methods: Uncertainty and Traceability

February 12, 2024
Author(s)
George Mulholland, Kaleb Duelge, Vincent A. Hackley, Natalia Farkas, John A. Kramar, Keiji Takahata, Michael Zachariah, Hiromu Sakurai, Kensei Ehara
Accurate measurements of particle diameter are necessary for quantitative characterization of key aerosol properties including the Cunningham slip correction, charging probability, the diffusion coefficient, the coagulation coefficient, and optical

Ultra-Low Phase Noise Frequency Division with Array of Direct Digital Synthesizers

December 25, 2023
Author(s)
Marco Pomponio, Archita Hati, Craig Nelson
In this article, we present a four-channel direct digital synthesis (DDS) design that operates with a common clock ranging from 500 MHz to 24 GHz and generates output frequencies up to 1.75 GHz. A key feature of this board is its custom field-programmable

Comparison of Direct and Indirect Measures of Transport Efficiency in Single Particle ICP-MS

December 16, 2023
Author(s)
Karen Murphy, Antonio Montoro Bustos, Lee L. Yu, Monique Johnson, Michael R. Winchester
Accurate calibration of the fraction of introduced sample that is transported to the plasma, termed "transport efficiency" (TE), is required for spICP-MS measurement of particle number concentration (PNC) and for measurement of particle size (diameter, PS)

NIST Office of Weights and Measures (OWM) Recognition Program Handbook, 7th Edition

December 11, 2023
Author(s)
Micheal Hicks, Georgia L. Harris, Katrice Lippa, Isabel Chavez Baucom, Elizabeth Koncki
Handbook 143 provides the National Institute of Standards and Technology (NIST) Office of Weights and Measures (OWM) performance standards and formalized procedures for the voluntary recognition of State legal metrology laboratories. This 2023 edition

Robotic Antenna Measurements

December 11, 2023
Author(s)
Josh Gordon
Robots excel at manipulating objects with 6 degree of freedom movement. A combination of well-defined kinematics, optimized control loops, and robust mechanical architecture make robots a versatile and capable platform for a range of applications where

INTERNATIONAL ROADMAP FOR DEVICES AND SYSTEMSTM 2023 EDITION METROLOGY

December 8, 2023
Author(s)
Elisabeth Mansfield, Bryan Barnes, R Joseph Kline, Andras E. Vladar, Yaw S. Obeng, Albert Davydov
The Metrology Chapter identifies emerging measurement challenges from devices, systems, and integration of new materials in the semiconductor industry and describes research and development pathways for meeting them. This includes but not limited to
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