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This handbook compiles uniform laws and regulations developed by the Committee on Laws and Regulations of the National Conference on Weights and Measures (NCWM). This edition contains amendments adopted by the NCWM at its annual meeting in 2008. It
The fundamental atomic physics of a gas laser transition is such that the transition frequency, or equivalently, the vacuum wavelength of the laser, cannot vary from its central value by more than a few parts in 106. The uncertainty of the gas laser
We used a cross capacitor to measure the relative dielectric permittivity ε r of O 2 at 273 K, 293 K, and 323 K and at pressures up to 6.5 MPa. Simultaneously we measured oxygen's complex refractive index n using a quasi-spherical cavity resonator at
Balasubramanian Muralikrishnan, Daniel S. Sawyer, Christopher J. Blackburn, Steven D. Phillips, Bruce R. Borchardt, William T. Estler
The American Society for Mechanical Engineers (ASME) recently released the ASME B89.4.19 Standard [1] on performance evaluation of spherical coordinate instruments such as laser trackers. At the National Institute of Standards and Technology (NIST), we can
Ronald G. Dixson, Ndubuisi G. Orji, B Bunday, J Allgair
As the size of integrated circuit features continues to decrease, the accuracy of measurements becomes more important. Due to greater emphasis on precision rather than accuracy, many of the measurements made in semiconductor fabs are not traceable to the
Ravikiran Attota, Michael T. Stocker, Richard M. Silver, Nathanael A. Heckert, Hui Zhou, Richard J. Kasica, Lei Chen, Ronald G. Dixson, Ndubuisi G. Orji, Bryan M. Barnes, Peter Lipscomb
In this paper we present overlay measurement techniques that use small overlay targets for advanced semiconductor applications. We employ two different optical methods to measure overlay using modified conventional optical microscope platforms. They are
We present a novel optical technique that produces nanometer dimensional measurement sensitivity using a conventional bright-field optical microscope, by analyzing two-dimensional through-focus scanning optical microscope (TSOM) images constructed using a
In the uncertainty budget of Rockwell hardness tests, microform geometric errors of the diamond indenter are a major contributor. The microform calibration of Rockwell diamond indenters has been one of the key steps for Rockwell hardness standardization
Flash laser detection and ranging (LADAR) systems are increasingly used in robotics applications for autonomous navigation and obstacle avoidance. Their compact size, high frame rate, wide field of view, and low cost are key advantages over traditional
JiYoung Chu, Quandou (. Wang, John P. Lehan, Ulf Griesmann, Guangjun Gao
In characterizing the performance of a phase-shifting interferometer, the dependence of the measured height on the spatial frequency is rarely considered. We describe a test mirror with a special height relief that can be used to measure the height
While the frequency dependence of the wireless channel may be negligible for narrow to wideband signals, it has been shown that modeling this dependence for bandwidths in excess of 2 GHz improves channel reconstruction up to 40%.Yet to our knowledge, only
This article describes a capillary flow meter whose maximum flow rate of 0.2 micromol/s (~0.2 cm3/min at ambient conditions) covers the range that is useful for calibrating spinning rotor gauges. Knowing the input pressure, output pressure, and temperature
Michael T. Postek, Andras Vladar, John A. Dagata, Natalia Farkas, Bin Ming, Ronald Sabo, Theodore H. Wegner
Biomass surrounds us from the smallest alga to the largest redwood tree. Even the largest trees owe their strength to a newly-appreciated class of nanomaterials known as cellulose nanocrystals (CNC). Cellulose, the world s most abundant natural, renewable
A new self-excited micro-oscillator is proposed as a velocity reference that could aid the dissemination of nanonewton-level forces that are traceable to the International System of Units (SI). An analog control system is developed to keep the actuation
David R. White, Samuel Benz, J Labenski, Sae Woo Nam, Jifeng Qu, H Rogalla, Weston L. Tew
This paper describes methods for reducing the statistical uncertainty in measurements made by noise thermometers using digital cross correlators, and in particular, for thermometers using pseudorandom noise for the reference signal. First, a discrete
This document describes NIST's high pressure natural gas flow calibration service (NGFCS). Flow calibrations are conducted offsite at the Colorado Experimental Engineering Station Incorporated (CEESI) in Garner, Iowa. A parallel array of nine turbine meter
Petr Cizmar, Andras Vladar, Bin Ming, Michael T. Postek
Resolution is a key performance metric, which often defines the quality of a scanning electron microscope (SEM). Traditionally, there is the subjective measurement of the distance between two points on special ''resolution'' samples and there are several
Ulf Griesmann, Quandou (. Wang, Nicolas Laurenchet, Johannes A. Soons
Calibration procedures for optical reference flats of phase-shifting interferometers (three-flat tests) are critically important if flatness measurements with low uncertainty are desired. In these tests, all combinations of three flats with unknown
Jun-Feng Song, P Rubert, Xiaoyu A. Zheng, Theodore V. Vorburger
The electro-forming technique is used at National Institute of Standards and Technology (NIST) for the production of standard reference material (SRM) 2461 standard casings to support nationwide ballistics measurement traceability and measurement quality
As part of a larger-scale thermophysical and transport property measurement project, the global decomposition kinetics of the aviation turbine fuel Jet-A was investigated. Decomposition reactions were performed at 375, 400, 425, and 450 °C in stainless
Since the Guide to the Expression of Uncertainty in Measurement (GUM) was published in 1993 it has changed the evaluation of physical and chemical measurements. In our days almost all high level measurements include a detailed evaluation of uncertainty
Eduard Rocas, Juan C. Collado Gomez, Jordi Mateu, Nathan D. Orloff, Alberto Padilla, Juan Callaghan, James C. Booth, Robert Aigner
This paper presents recent measurements and modeling of the third order intermodulation products of a Film Bulk Acoustic Resonator (FBAR), for a various values of frequency spacing between driving tones. The frequency dependence of voltage and current in
Jeffrey T. Fong, James J. Filliben, Nathanael A. Heckert, Roland deWit
A fundamental mathematical modeling and computational tool in engineering and applied sciences is the finite element method (FEM). The formulation of every such problem begins with the building of a mathematical model with carefully chosen simplifying
Gregory W. Vogl, Jason J. Gorman, Gordon A. Shaw, Jon R. Pratt
A new self-excited micro-oscillator is proposed as a velocity standard for dissemination of nanoNewton-level forces that are traceable to the International System of Units (SI). The microfabricated oscillator is top-coated with magnetic thin films and