Combined Result And Associated Uncertainty From Interlaboratory Evaluations Based On The ISO Guide
Author(s): Raghu Kacker, Raju Datla, Albert Parr
Abstract/Introduction:
[Abstract Not Available]
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Document ID:
B3BE4CF7
Uncertainty Analysis Of A High-Speed Dry Piston Flow Prover
Author(s): Harvey Padden
Abstract/Introduction:
This paper discusses a novel high-speed piston prover that uses a clearance seal to achieve very low uncertainties. We will review the instruments design and provide an uncertainty analysis for three sizes of our internal reference provers, designed for flows of 10 mL/min to 50 L/min. The results were expanded single-reading uncertainties at 2X coverage range from 0.064% to 0.073%. The instrument also has the capability to average a number of readings, potentially reducing the above uncertainties by a significant amount.
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Document ID:
2C7E6D61
New And Future Capabilities For Cw Laser Power Measurements At NIST.
Author(s): Joshua Hadler
Abstract/Introduction:
As the commercial, industrial, and military applications for lasers expand, so do the demands that customers place on the calibration services that NIST provides. Calibration services in the CW Laser Radiometry Project of the Optoelectronics Division at NIST meet many of these needs and continue to expand to meet new needs. This Project focuses on selected critical parameters intrinsic to sources and detectors, especially the calibration of optical-fiber power meters and laser power or energy meters at commonly used wavelengths and powers or energies. In addition, special test measurements are available for linearity, spectral responsivity, and spatial and angular uniformity of laser power meters and detectors. This presentation will explore recent developments in laser sources and standards for improving calibrations of laser power and energy.
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Document ID:
830C192A
The Effects Of Thermal Phenomena On The Accuracy Of Critical Flow Venturi Based Flow Rate Measurements
Author(s): Richard W. Caron, Charles L. Britton, Thomas m. Kegel
Abstract/Introduction:
As air flows through a critical flow venturi (CFV), the Mach number increases steadily from the inlet to the exit. The dependence of static air temperature on Mach number results in significant thermal gradients through the venturi. The difference between inlet and exit temperature can be as great as 190 Degrees Celsius (374 Degrees Fahrenheit) when the flow is fully expanded. Temperature gradients may result in distortion of the CFV geometry due to the material coefficient of expansion. When using a critical flow venturi to perform high accuracy flow measurements, even a small change in venturi throat area will introduce unwanted errors if the geometric distortion is not accounted for.
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Document ID:
B1B46EB1
Statistical Control Of A Flow Calibration Process
Author(s): Thomas Kegel
Abstract/Introduction:
This paper summarizes the statistical process control program in place in the CEESI Iowa flow facility. Data have been obtained from three meters over a three year period of time. Conclusions are drawn regarding consistency of operation and measurement uncertainty.
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Document ID:
E6A7DB01
Youden Analysis Of Flowmeter Data - Four Case Studies
Author(s): Thomas Kegel
Abstract/Introduction:
This paper describes Youden1 analysis associated with flowmeter performance.
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Document ID:
817956B6
Principles Behind The Requirements Of ISO/IEC 17025
Author(s): Ned Gravel
Abstract/Introduction:
ISO/IEC 17025 is a standard that sets out the specific requirements to be met by laboratories wishing to achieve the production of competent results as a matter of course. These requirements were developed by groups of laboratory experts from around the world over the course of 30 years. From the first, laboratory competence has been the paramount consideration. In todays world, recognition of such competence generally requires that laboratories which have implemented the requirements of the standard obtain accreditation. This accreditation is the mark of recognition of their competence. Accreditation involves assessment and, like all audit-associated activities, assessment of technical competence requires trained assessors to deliver these assessments. Assessors must be fully cognisant of each of the requirements in the standard.
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Document ID:
239ACC26
Implementation Of An ISO/IEC 17025-based Quality System RF/Microwave And Millimeter Microwave
Author(s): Dr. Li Pi Su
Abstract/Introduction:
The USA Army Primary Standards Laboratory, APSL, is the only USA Army primary standards laboratory serving the whole Army primary-level calibration and testing needs. The APSL is always committed to provide services to the warfighter and its customers with accurate equipment/products which are traceable to the National Institute of Standards and Technology (NIST), delivered on-time, and continuously seeking for innovative ways to achieve excellence in laboratory performance. Since 1998, the APSL has obtained the accreditation, based on ISO/IEC 17025 Quality System, from the American Accreditation of Laboratory Association (A2LA).
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Document ID:
F56E0766
Uncertainty Evaluation And Modelling Of Measurements
Author(s): Klaus-Dieter Sommer, Manfred Kochsiek
Abstract/Introduction:
During the last decade, the Guide to the Expression of Uncertainty in Measurement (GUM) 1 has become a worldwide-recognized standard for the evaluation of the measurement uncertainty at least at national metrological institutes, calibration laboratories and verification authorities. For practical use, the GUM excels in: Providing a consistent procedure for evaluating and expressing uncertainty Offering an easy way to implement computer-aided uncertainty budgeting. The basic steps of the GUM procedure are: modelling of the measurement, and quantitative description of the existing knowledge about the input quantities in accordance with the methods type A (evaluating by statistical means) and type B (evaluation by other means).
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Document ID:
E066FD82
The Business Of Calibration
Author(s): Greg Powell
Abstract/Introduction:
[Abstract Not Available]
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Document ID:
0CED40C5
Calibration Intervals And Measurement Uncertainty Based On Variables Data
Author(s): Dennis Jackson
Abstract/Introduction:
Generally, the data gathered during a calibration test includes only the result of the test, that is, whether the test equipment was in or out of tolerance. The actual measurement data obtained when doing calibration testing provides a wealth of information concerning the state of the test equipment. In fact, this data is the primary source of information concerning uncertainty trends over time. This paper shows methods for using this data to predict the correct calibration interval, as well as estimating measurement uncertainty. The basic idea is to use the calibration comparison data to predict drift and variability trends using regression techniques. The regression models are then used to predict measurement reliability curves and calibration intervals that meet a reliability target. The regression models also allow the estimation of symmetric and non-symmetric measurement uncertainty limits.
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Document ID:
5EBDC0DE
V-B Understanding The Accreditation Process
Author(s): Chester Franklin
Abstract/Introduction:
It will explain how the accreditation process is established and monitored so that international recognition can be assured. There are standardized procedural steps in the process of accreditation to ISO/IEC 17025 that are followed by any accrediting body in the world, which has signed mutual agreements with the accrediting community. This paper includes a flow diagram of the common accreditation process. These process steps, established by ISO/IEC Guide 58, Calibration and Testing Laboratory Accreditation Systems - General Requirements for Operation and Recognition, and to which an AB must adhere, are defined and discussed. This paper also includes a chart showing the hierarchy of the international accreditation community, defining such organizations as ILAC, APLAC, EA and NACLA, along with the three U.S. ABs that have signed MRAs with NACLA.
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Document ID:
FD3CA908
The Publication Of ISO 10012 Requirements For Measurement Processes And Measurement Systems
Author(s): Rolf B. F. Schumacher
Abstract/Introduction:
Beginning in 1962, I contacted Dr. Churchill Eisenhart. He was then the Chief of the NBS (National Bureau of Standards, now NIST) department of mathematics. The NBS is a branch of the US Dept. of Commerce. And he carried the major weakness of all metrologists for not knowing how to determine the uncertainty of NBSs measurements. He had just written a paper and published in the NCSL first meeting in Denver, CO that year, Realistic Evaluation of the Precision and Accuracy of Instrument Calibration Systems, and received the NCSL Wildhack Award for it several years later, although few had any idea what it was all about. Eisenhart had shown that the main work by Dr. Walter Shewhart, in his 1920s, Economic Control of Quality of Manufactured Product produces measurements results that enable the determination of measurement uncertainties. During World War II, the American industry, working for the US military had to use Shewharts method of quality assurance to such a success that Dr. Shewhart was widely accepted as the Father of Modern Quality Assurance.
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Document ID:
C82E0A69
The Value Of Proficiency Testing
Abstract/Introduction:
[Abstract Not Available]
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Document ID:
44DAC79E
Using Measurement Science To Build A Business Case & Metrics For Your Test Equipment Management Business
Author(s): Paul Mcnamara, Mark Connors
Abstract/Introduction:
Brutally competitive markets are driving companies to design, build, and improve their products faster and at lower cost. Those who can add value to this process will survive and thrive, those who cannot will be marginalized, many losing their jobs in the process. Within your business there is a Test Equipment Management business operating that many either dont know about or dont put the appropriate attention on. Like any business without strong metrics and rigorous financial statements the bottom line results are poor. Because people dont see or understand this function as a business within a business they only see the symptoms of problems on the bottom line of the total enterprise. The result: people lose their jobs, critical investments in technology are overlooked and project dates are missed.
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Document ID:
54D599BF
Ensuring Quality Service And Value From Your Vendors
Abstract/Introduction:
Recently the news media has been full of stories of poor oversight of Vendors by many industries. Accounting firms not properly auditing corporations, Crematoriums not creating remains for years, Auto repair firms charging for work not done, worn parts not being replaced on aircraft. These are just a few examples. Every organization in the Metrology community will rely on outside vendors for some type of instrument services. These services include Equipment Calibration, Repair, Validation, Rental, Lease and Purchase. Here are a few of the typical of comments frequently used. Vendor X is good because they are ISO 9000 approved, or they must be doing a good job because company Y uses them, While almost all vendors are ISO approved or compliant, ISO only ensures that a quality system is in place. It does nothing to ensure that the quality system is actually being followed, let alone enforced. While Navlap and A2LA help to ensure competence, it is still up to the customer to monitor vendors.
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Document ID:
2205B773
Missile Test Confidence Via Test Systems Certification And Associated Data Analysis
Author(s): Mr. David Maupin
Abstract/Introduction:
This paper discusses missile data analysis from production and fleet return test runs. This data can be used to detect a wide array of potential problems. I will look at how this data can be used by the manufacturers and depots that collect it. I will also examine data analysis visual display chart types and how to effectively group the results. Future trends in the use of the analysis programs will also be briefly explored.
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Document ID:
62582171
Supporting Legacy Naval Test Equipment
Author(s): Maria Olea, Zareh Zakarian
Abstract/Introduction:
Most fighter pilots are familiar with the Ault Report 1 that established the Navys Top Gun school. What is less known about the Ault Report is that it pointed out the need for a rigorous testing program to ensure the reliability and availability of missiles. That need has not changed as shown in the recent report by Thomas P. Christie 2 (Operational Test and Evaluation) and by the Government Accounting Offices (GAO) audit of avionics support equipment. The need for a rigorous testing program is, in fact, greater today than in the past. This testing program should not only be rigorous, but also needs to include a thorough and well-planned calibration program. Weapons systems are considerably more complex than in the 1970s. These systems are also much more capable and greater reliance is placed on each individual weapon each time.
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Document ID:
E09EABB2
Repeatability And Reproducibility Uncertainty In The Measurement Of Trace Moisture Generated Using Permeation Tubes
Author(s): Peter H. Huang, Raghu N. Kacker
Abstract/Introduction:
[Abstract Not Available]
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Document ID:
EDC86306
A 193 Nm Laser Detector Nonlinearity Measurement System
Author(s): D. Keenan, H. Laabs, S. Yang, m. Dowell
Abstract/Introduction:
To meet the semiconductor industrys demands for accurate optical measurements, we have developed a method to characterize the nonlinear response of detectors used with 193 nm excimer lasers. The system we employ is referred to as the correlation method since the response of the detector under test is measured against a linear monitor detector. This system is complementary to our other excimer laser power and energy calibration services and provides a quantitative measurement of a detectors response over a large range of power or energy. Detectors are typically used over a larger range of power or energy than that covered by a single calibration point. Measurement uncertainty can be introduced if the response as a function of power or energy is not quantified. Range discontinuity, such as changing the detectors amplification, can also introduce additional measurement uncertainty. Experimental results revealed nonlinearity of some UV detectors as high as 8 %.
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Document ID:
276A5D6C
Metrology And Quality Assurance For Surveillance Of Gas Compositions Over PuO2
Author(s): Catherine French-Sidoti, Lawrence Kreyer, Laura Worl
Abstract/Introduction:
Until the late 1980s, a primary mission of the Department of Energy (DOE) has been the production of nuclear materials for nuclear weapons. Termination of the Cold War in 1989 and the subsequent nuclear weapons treaties dramatically decreased the inventory needs for nuclear weapons. These activities resulted in the consolidation of nuclear material inventories and activities, generating substantial amounts of surplus nuclear materials ranging from plutonium metal and pure oxides to impure plutonium residues. Packaging and storage of these materials in physically and environmentally safe configurations for significant time periods were required.
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Document ID:
2384AA35
Statistically-Defined-Parameter Modeling Of Back-Pressure Sensor System
Author(s): Vladimir B. Bokov
Abstract/Introduction:
A novel method has been fashioned for development of statistically-defined-parameter model of back-pressure sensor system. This method combines the traditional approach in elaboration of lumped parameter model and, for attainment its optimum precision, employs the statistical modeling of conjectured variable lumped parameters. Basic concepts and theoretical analysis of the lumped-parameter modeling and the statistical modeling of the variable lumped parameters are described. This combined modeling method was employed for modeling of the novel type of air gauging system with elongated nozzle structure. From model analysis it was found that the statistically-defined-parameter modeling method permits to attain the minimum discrepancy in comparison with experimental evidence.
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Document ID:
7C50ABE7
Development Of A 0.2 % High-Speed Dry Piston Prover
Author(s): Harvey Padden
Abstract/Introduction:
[Abstract Not Available]
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Document ID:
D96AC29D
Condensation Hygrometers As Humidity Transfer Standards
Author(s): Ken Soleyn
Abstract/Introduction:
Condensation hygrometers provide direct and fundamental measurement of dew point temperature by regulating the flow of coolant or regulating the electrical current through thermoelectric coolers to control a target surface to a temperature where the formation and evaporation of dew or frost an equilibrium. The temperature of the target is by definition the dew or frost point temperature. Dew point temperature is a measurement of the amount of water vapor in air or other gases.
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Document ID:
12C27880
The Value Of Proficiency Testing
Abstract/Introduction:
[Abstract Not Available]
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Document ID:
3811B7FA
Considerations For Single Mode Fiber Optic Instrument Calibration
Author(s): Joe Swanzy
Abstract/Introduction:
The increasing popularity of optical fiber communication networks has created a demand for the calibration of optical test equipment. Three relatively new standards have been generated by the IEC for calibrating optical test instruments. IEC 61315 discusses calibration of the Power Meters (PM) IEC 62129 covers Optical Spectrum Analyzers (OSA) and IEC 61746 covers Optical Time Domain Reflectometers (OTDR). PMs, OSAs, and OTDRs dominate the optical fiber test instrument area. Using information from the IEC standards, this paper looks at methods for calibrating OSAs and OTDRs, looks at sources of uncertainty, and discusses the devices used in their calibration. The paper will discuss common equipment that every calibration lab should have.
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Document ID:
536C6F1B
Bullet Signature Measurements At NIST
Author(s): J. Song, L. Ma, E. Whitenton, T. Vorburger
Abstract/Introduction:
The RM (Reference Material) 8240 standard bullets are currently under development at the National Institute of Standards and Technology (NIST) to support the coming National Integrated Ballistics Information Network (NIBIN). A bullet signature measurement system based on a stylus instrument is developed at NIST for the signature measurements of RM standard bullets. A comparison parameter and an algorithm using autocorrelation functions are proposed for qualifying the bullet signature differences. Initial test results for the bullet signature measurement system are as expected from previous theoretical analyses. The proposed parameter and algorithm will be used in the analyses of results from the bullet signature measurement system for the quality control of NIST RM 8240 standard bullets.
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Document ID:
3EC424C3