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Aaron N. Johnson, C L. Merkle, Michael R. Moldover, John D. Wright
We computed the flow of four gases (He, N 2, CO 2, and SF 6) through a critical nozzle by augmenting traditional computational fluid dynamics (CFD) with a rate equation that accounts for τ relax, a species-dependent relaxation time that characterizes the
NIST Handbook 150-20-2005, NVLAP Information Technology Security Testing: Common Criteria, presents the technical requirements and guidance for the accreditation of laboratories under the NVLAP Common Criteria Testing LAP. The 2005 edition incorporates
NIST Handbook 150-4, NVLAP Ionizing Radiation Dosimetry, presents the technical requirements and guidance for the accreditation of laboratories under the NVLAP Ionizing Radiation Dosimetry LAP. The 2005 edition incorporates changes resulting from the
NIST Handbook 150-5, NVLAP Construction Materials Testing, presents the technical requirements and guidance for the accreditation of laboratories under the NVLAP Construction Materials Testing LAP. The 2005 edition incorporates changes resulting from the
NIST Handbook 150-8, NVLAP Acoustical Testing Services, presents the technical requirements and guidance for the accreditation of laboratories under the NVLAP Acoustical Testing Services LAP. The 2005 edition incorporates changes resulting from the release
By means of concrete examples, we discuss the determination of an uncertainty budget for calibration of thermocouples by comparison techniques. In the first example, the calibration of a type T thermocouple (copper versus copper-nickel alloy) in a stirred
Gold versus platinum thermocouples have uncertainties superior to all other thermocouples over the range 0 C to 1000 C. In this paper, we describe the properties of 21 specially-constructed gold versus platinum (Au/Pt) thermocouple thermometers, each
John D. Wright, Aaron N. Johnson, Michael R. Moldover, Gina M. Kline
This document provides a description of the 34 L and 677 L pressure, volume, temperature, and time (PVTt) primary gas flow standards operated by the National Institute of Standards and Technology (NIST) Fluid Flow Group. These facilities are used to
R L. Rusby, Christopher W. Meyer, Weston L. Tew, D I. Head, K D. Hill, O Tamura, P A. de Groot, B Fellmuth, A Storm, A Peruzzi, J Engert, D N. Astrov, Y Dedikov, G A. Kytin
At its meeting in 1996 the CCT initiated five Key Comparisons to test the equivalence of realisations of the ITS-90 between National Measurement Institutes. CCT-K1 covers the temperature range from 0.65 K to 24.5561 K, in which the ITS-90 is defined by
The Calibration Laboratories Accreditation Program was developed by the National Voluntary Laboratory Accreditation Program (NVLAP) at the National Institute of Standards and Technology (NIST) as a result of interest from private industry and at the
The NVLAP Directory of Accredited Laboratories is published annually and provides a listing of laboratories accredited by the National Voluntary Laboratory Accreditation Program (NVLAP). Over 800 accreditations in 25 fields of testing and calibration are
The NVLAP Directory of Accredited Laboratories is published annually and provides a listing of laboratories accredited by the National Voluntary Laboratory Accreditation Program (NVLAP). Over 800 accreditations in 25 fields of testing and calibration are
The National Institute of Standards and Technology (NIST) Calibration Services Users Guide: Time and Frequency Measurements provides detailed descriptions on NIST calibration and special-test services available. To characterize instruments and devices that
Two facilities have been constructed at NIST for realizing and maintaining the ITS-90 below 84 K. The first facility is an integrated low temperature realization system that realizes the ITS-90 below 84 K in its entirety and which we refer to as the Low
We have established a measurement system for the direct calibration of energy density (dose) meters. It consists of beam-shaping objects, a beamsplitter, calibrated apertures, a beam profile monitor, an energy monitor, and a transfer standard. The 193 nm
The National Institute of Standards and Technology operates and maintains piston gage pressure standards from 7 kPa to 280 Mpa, a span of over 4 decades in pressure. Gas capabilities range from 7 kPa to 1000 Mpa, and oil capabilities range from 1 Mpa to
Ali L. Eichenberger, Mark W. Keller, John M. Martinis, Neil M. Zimmerman
A new type of capacitance standrd based on counting electrons has been built. The operation of the standrd has already given very promising results for the determination of the value of a cryogenic vacuum-gap capacitor. The new capacitance standard