System Diagnostic And Control Update Using Wireless Links
Author(s): Masoud Fathizadeh, Akram Hossain
Abstract/Introduction:
In many industries there is a growing demand for precise and reliable speed drives capable of giving long term stability and good transient performance. Because of high efficiency, low initial cost and simple control circuitry, induction motors with slip recovery or frequency control represent two of the most important classes of variable speed drives. In recent years different schemes have been implemented to develop good and reliable speed control. Many of these circuits utilize the power of microprocessor or microcontrollers. Microcontrollers are versatile and give freedom to the operator to design and fine tune control loops to fit any applications. However, these controllers are local and diagnostic and data information data is sent through wire to the front panel.
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Document ID:
12663B7E
New Calibration Strategies To Support Reduced Watch Standing
Author(s): Randy Rupnow
Abstract/Introduction:
[Abstract Not Available]
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Document ID:
EEF713CD
Calibration Cooperation: Cooperation In Field Calibration
Author(s): Gerhard Mihm
Abstract/Introduction:
With proceeding globalization, cost cuts in the military and resulting needs for cooperation in military operations, calibration requirements need to be regarded too. With an increasing number of measurement equipment and the requirement of its availability in the field, field calibration instead of exchange of equipment is a practicable and economic solution. Planning cooperation in field calibration, a number of problems and issues have to be solved. Different languages, experiences, equipment (mobile laboratories etc.) have to be regarded. The German Armed Forces have experience in field calibration.
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Document ID:
4EA54421
No Standardization In Close-Equipment Documents And Requests For Practice
Author(s): Peter Jager, Alte Heerstr
Abstract/Introduction:
The inexorable progress in science and technology inevitably causes a development and an influencing control on most modern measuring technique / metrology. Branches of industry specialize and supply their customers with technology and know-how. However, technology islands develop, which cause a lot of problems to users who utilize a large range / variety and spectrum of equipment. The German Armed Forces and most European military services experience chasms between modern and conventional technology. The absence of standardized close equipment documentation causes and intensifies these problems. The specialization of the industry on special fields or product groups does not equate to standardised procedures and the idea of comparable technical levels or quality. Organisations, which have a large spectrum of measuring and metrology instruments - covering various parameters and several generations of equipment - are put in the position of continuously searching for updated processes or identifying possible compromises. The presentation tries to point out general and basic demands for more standardisation and compability and demands for standardised close-equipment documentation.
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Document ID:
C6B86EDD
ISO/IEC 17011:1994, Its Relation To ISO/IEC 17025:2005 And Why Laboratories Should Know It
Author(s): Keith Greenaway
Abstract/Introduction:
[Abstract Not Available]
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Document ID:
0CAA35B9
The Quality System For NIST Measurement Services
Author(s): Sally S. Bruce
Abstract/Introduction:
As the National Metrology Institute (NMI) for the United States, the National Institute of Standards and Technology (NIST), formerly the National Bureau of Standards, has provided measurement services in the form of physical standards, calibrations, and reference materials for more than 100 years http://www.nist.gov/ . The basic service areas comprise the following measurement capabilities: acoustics, ultrasound, and vibration electricity and magnetism length mass and related quantities photometry and radiometry amount of substance ionizing radiation thermometry and time and frequency. Through these measurement services NIST offers its customers some of the highest accuracy measurements available while providing traceability to the International System of units (SI).
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Document ID:
88EEE06D
Usmc Lessons Learned
Author(s): Robert S. Schafer, James Blease
Abstract/Introduction:
Simply gathering calibration data, no matter how much or little is not enough. In order to grow and compete in the commercial world, companies must be able to capture and understand their calibration data. Companies need defined business practices for data capture, and storage if they hope to use the data to their advantage. These same rules have to be applied to Military entities if their programs are to survive and not fall into stagnation. The paper will highlight the evolution of the calibration program for Marine Corps Ground Fleet from a technological standpoint. A roadmap from the days of pen and paper to todays modern lab will show both the highs and lows encountered along the way. Through each phase we will see the hazards encountered in data collection, the impact it had on data and ultimately the Marine Corps Ground Fleet Calibration Program itself.
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Document ID:
DFF5882D
Progress In Metrology From The Adoption Of The Absolute Units In 1948 To The Application Of Uncertainty Today
Author(s): David W. Braudaway
Abstract/Introduction:
The history of the electrical units beginning with the 1948 change from the International Electrical Units to the Absolute Electrical Units is reviewed. The change from the conventional methods of expressing accuracy through development of the uncertainty methods is followed. Included are effects of some of the attitudes and practices as instruments and standards become more precise and automation and computers were applied. The development of metrological uncertainty is also reviewed with a discussion of the effects of international recommendations and standards. The necessity of knowing not only values but also their uncertainty is expressed the use and effects of the coordinated values for the Fundamental Physical Constants is reviewed.
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Document ID:
EA5EE426
Uncertainty Associated With Virtual Measurements From Computational Quantum Chemistry Models
Author(s): Karl K. Irikura, Russell D. Johnson III, Raghu N. Kacker
Abstract/Introduction:
A value for the measurand determined from a computational model is frequently referred to as a virtual measurement to distinguish it from a physical measurement, which is determined from a laboratory experiment. Any measurement, physical or virtual, is incomplete without a quantitative statement of its associated uncertainty. The science and technology of making physical measurements and quantifying their uncertainties has evolved over many decades. In contrast, the science and technology of making virtual measurements is evolving. We propose an approach for quantifying the uncertainty associated with a virtual measurement of a molecular property determined from a computational quantum chemistry model.
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Document ID:
DBF1BBC9
Traceabilityor Else
Author(s): Emil Hazarian
Abstract/Introduction:
This paper will discuss the traceability as a fundamental, cardinal metrological concept, attempting to clarify the meaning and the proof necessary every time a measurement activity is performed. The information on each hierarchical level will be explained based on examples and using flow charts created for diverse measurement quantities.
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Document ID:
444D9474
Ensuring The Quality Of Measurement Data
Author(s): Robert m. Graham
Abstract/Introduction:
[Abstract Not Available]
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Document ID:
A0DF30D3
How To Maintain The Certified Calibration Technician Certification
Author(s): Dilip A. Shah
Abstract/Introduction:
The Certified Calibration Technician Exam has been administered since June 2003. Every three years, Certified Calibration Technicians have to renew their certification. Many metrology and calibration technicians will face their first renewal on June 2006 and December 2006. This presentation describes several options for the renewal process.
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Document ID:
8844AE89
New Generation Of Motor Control Using Dependable Wireless Conduit
Author(s): Akram Hossain, Masoud Fathizadeh
Abstract/Introduction:
In recent years telecommunication and computer industries have shown sweeping improvements and introduced numerous new and innovative technologies into the marketplace. Many of these innovations have been implemented and commercialized for control and data acquisition in the industrial process arenas. Currently reliable and economical wireless links for industrial control and data acquisitions are readily available and can be integrated into process control. However, wireless feedback control of an ac and dc motor has yet to be adopted by the manufacturing industry. The reason for that is the lack of reliable wireless control conduit for controlling and interfering in an industrial environment. This paper presents a method and a set of experimental data that are collected from a controlled three phase induction motor with a feedback control loop over a wireless conduit.
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Document ID:
E224107F
Computer Technology Increases Productivity, Improves Repeatability, Achieves Compliance And Saves Money
Author(s): Christopher J. Campbell
Abstract/Introduction:
Metrology professionals can help increase productivity and efficiency, achieve and maintain compliance, improve process repeatability by minimizing opportunities for human error and increase internal/external customer satisfaction while saving money through advances in computer technologies.
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Document ID:
ABCC8C37
Application Of Quantum Electrical Standards In Electronic Mass Experiment
Author(s): Yi-Hua Tang
Abstract/Introduction:
[Abstract Not Available]
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Document ID:
BFE8F91C
Signal Sourcing Requirements For Spectrum Analyzer Calibration
Author(s): Paul Roberts
Abstract/Introduction:
Calibrating a Spectrum Analyzer usually involves a variety of measurements, with each requiring a suitable input signal. A typical procedure generally utilizes a number of signal generators together with other pieces of equipment to generate the signals and ensure their accuracy. This paper provides an overview of spectrum analyzer calibration with discussion of the most common calibration tests, their signal requirements, and approaches for meeting those requirements.
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Document ID:
F62A050C
Voltage Envelope Vs. Power Envelope
Author(s): Woo Chi
Abstract/Introduction:
According to the IEEE definition, pulse parameters are defined at 10%, 50%, and 90% of the pulse. But this does not specify whether the definition is in terms of the voltage or the power. In the department of defense (DOD), many IFF/TACAN and other radar equipment uses the pulse modulated microwave signal for transmitting/receiving information. There is a clear distinction between two definitions, but it was not apparent in the old days when the measurement was made using a crystal detector and an oscilloscope. Nowadays, more precise techniques are available such as peak power analyzers and high bandwidth oscilloscopes. This advance in technology revealed the difference between the two definitions more clearly but also caused confusion on which definition to follow. This paper will examine the difference between voltage envelope and power envelope, then show an actual case that occurred during a NAVAIR standard procurement. The confusion over the specifications led to one manufacturer making the test equipment using the voltage definition, and another manufacturer using the power definition. Finally, recommendations will be made on steps to prevent this in the future.
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Document ID:
EE5F519C
A Direct Comparison System For Measuring Radio Frequency Power (100 Khz To 18 Ghz)
Author(s): Ronald Ginley
Abstract/Introduction:
A direct comparison power measurement system has been developed to measure power sensor effective efficiency (?e) in the 100 kHz to 18 GHz frequency range. This system is capable of measuring thermistor and thermoelectric based power sensors. Several problems needed to be addressed in the development of the system. These included rf leakage from the power sensors and its effect on system electronics, the sensitivity of power meter and digital volt meter to extraneous signals, and the effect of compensation beads, if there were any, in the sensors. The system design, discussion of the most important problems, the uncertainty analysis for the system, and comparison to measurements made by the NIST 0.05 GHz to 50 GHz system and the voltage/impedance technique will be covered.
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Document ID:
B56F5257
Remote Calibration Of A Gps Timing Receiver To UTC(NIST) Via The Internet*
Author(s): Michael A. Lombardi, Andrew N. Novick, Robert m. Graham
Abstract/Introduction:
The timing pulse from a Global Positioning System (GPS) receiver is typically within 1s of Coordinated Universal Time (UTC) kept at NIST, called UTC(NIST), even if the receiver and antenna have not been calibrated for delays. However, it is not possible for most laboratories to make an accurate measurement of their GPS receivers time offset with respect to UTC(NIST), or to monitor its continuous performance. This paper presents a method for remotely calibrating a GPS timing receiver at the customers location with respect to UTC(NIST) using the commonview GPS technique and the Internet. We present data from a remote calibration of a GPS timing receiver located at Sandia National Laboratories in Albuquerque, New Mexico, about 561 km from the NIST Laboratories in Boulder, Colorado. The uncertainty of the calibration is shown to be less than 50 ns.
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Document ID:
83315114
Determination Of Process And Calibration Tolerances And Correcting Oot Observations And Events With Appropriate Response
Author(s): Marcus Mcneely
Abstract/Introduction:
[Abstract Not Available]
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Document ID:
B8C40835
Roses Are Red, Violets Are Blue You Can Be Paperless And Wireless, Too!
Author(s): Jay L. Bucher
Abstract/Introduction:
Are you still filling in your forms longhand, and printing hardcopies for review? This papers for you. Do you still file your records in metal cabinets or desk drawers? Then this papers for you. Want to improve your productivity, reduce costs, eliminate correction errors, and be able to actually read what is in your records? Then this paper is definitely for you. And I havent even mentioned going wireless! Everyone is expected to do more with less (which is physically impossible), so improving productivity, in conjunction with saving both time and money, could be the silver bullet your program needs. Going paperless and wireless can take your calibration program to the next level with minimal investment while allowing you to meet all your quality compliance requirements.
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Document ID:
A9159633
Calibration Training Programs At Abbott Laboratories
Author(s): David Whitham
Abstract/Introduction:
Abbott Laboratories is a manufacturer of pharmaceutical, medical device and nutritional products. The companys Corporate Metrology department provides support to locations worldwide. Key personnel in the calibration process include technicians, calibration coordinators, and instrument specifiers. With emphasis on company specific calibration program requirements, a combination of instructor led and web based training programs have been developed for these audiences. An overview of these training programs, successes and lessons learned will be presented.
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Document ID:
BAFE75FE
Cmm Calibration From An Outside Service Provider To The In House Capability
Author(s): Shawn Mason, Michael Czech
Abstract/Introduction:
This paper will present the in-house development and implementation of a calibration process for calibrating CMMs using a Master Ball and Step Gages.
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Document ID:
64FC3F15
Uncertainties Related To Thermal Expansion In Dimensional Metrology
Author(s): Ted Doiron
Abstract/Introduction:
In dimensional measurement the uncertainty is often dominated by the effects of thermal expansion. In this paper I discuss these effects, their sources, and the methods used to determine the uncertainty components. In an extended example, the thermal uncertainty components for the measurement of a steel gage on a one dimensional measuring machine (UMM) is derived for different levels of laboratory temperature control and measurement.
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Document ID:
3A325E6F
Rational Design Requirements For A Set Of Overlapping Production Gas Flow Standards To Cover The Flow Range 3*10-1 To 3*105 Sccm.
Author(s): Thomas O. Maginnis
Abstract/Introduction:
Progress in thermal mass flow controller technology (multigas, multirange, digital, userconfigurable MFCs) has advanced to the point where production calibration of each MFC is required over a 40:1 flow turndown to an accuracy specified as a fixed percentage ( 0.25%) of flowrate. To meet todays requirements and provide for future MFC improvements requires production calibration standards with much increased flow range and improved accuracy. The re-calibration burden of keeping numerous production flow standards self-consistent and accurate must be balanced against the metrological advantage of substantial overlap in the ranges of the production standards. Some overlap is essential to demonstrate end-to-end consistency and avoid coverage gaps, yet too much overlap can add significant costs of ownership and operation because the recalibration cost scales as the product of the total number of production standards required and the recalibration frequency. This paper will explore a rational approach to setting of production flow standard design requirements by developing the quantitative relationships between flow turndown of individual flow standards, degree of overlap of adjacent standards, total number of standards required to cover the necessary range, and estimated cost of maintaining the production standards in calibration.
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Document ID:
4E7EACA2
The International Cipm Key Comparison Reference Values For Natural Gas Flow Flow At High Pressure
Author(s): D. Dopheide, B. Mickan, R. Kramer, M.van Der Beek, G. Blom, J. P. Vallet, O. Gorieu
Abstract/Introduction:
The CIPM decided in 1999, in accordance with the CIPM Mutual Recognition Arrangement (MRA) 2, to conduct Key Comparisons (KCs) 1 among national primary standards of selected NMIs in the subject field high-pressure gas. This includes natural gas and compressed Air and/or Nitrogen. The members of the responsible CCM Working Group for Fluid Flow (WGFF) elected PTB and NMi-VSL as the pilot laboratories for this Key Comparison (KC). This report comprises the results for the natural gas flow Key Comparisons and the final outcome and has been agreed by all participants and the CCM in April 2005. The results of such a Key Comparison are the Key Comparison Reference Value (KCRV), which is considered to be the worldwide best available realization of the unit and the degree of equivalence between the participating facilities and the KCRV. This report describes the KCRV and well as the degree of equivalence for the natural gas flow at high pressure.
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Document ID:
B987BA3A
Comparisons Of Viscous-Sealed Provers With Lne And Studies Of Piston - Cylinder Leakage
Author(s): Harvey Padden
Abstract/Introduction:
Inter-laboratory comparisons DryCal medium and large sized cells had validated our uncertainty analyses for flows above 100 sccm. However, we wished to test the lowest flow range using our smallest cell. LNE (Laboratoire National de Metrologie et dEssais), in Paris, performed a calibration over the complete flow range of 5 to 50,000 sccm using their dynamic gravimetric standard, repeating the tests after six months to test long-term reproducibility (drift). All results of the LNE comparison were favorable. However, at 5 sccm the ML-800-10 cell was near the limit of its allowable uncertainty. Perhaps this was the result of inaccuracies in our calibration of the tare leakage value of the viscous-sealed piston. Therefore, we investigated piston leakage test methodologies, leakages constancy with flow and the ability to predict leakage for varying gas species. We evaluated a number of leakage calibration methods after building a new, 0.25C stability, laboratory. We finally decided upon a successive-inversion technique, with leakage being half the magnitude of the difference between successive upright and inverted readings of flow. We were able to prove that leakage was invariant with flow and to assess the magnitude of error using varying gas species.
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Document ID:
52BCDB52
Thermal Mass-Flow Sensor Zero Offset
Author(s): Chiun Wang
Abstract/Introduction:
Thermal mass-flow sensors are normally calibrated only with an inert gas before they are used for measuring the flow of process gases. It was frequently observed that the sensor zero-offset shifts slightly when the process gas is introduced, even after the sensor has been zeroed perfectly with the inert gas. This study shows how gas thermal conductivity can affect the no-flow output of a thermal mass-flow sensor with imperfect symmetry.
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Document ID:
2309092C
Long-Term Resistance And Ratio Stability Of Sprts, Comparing Metal Sheaths Vs. Fused Silica Sheaths
Author(s): Mingjian Zhao, Rick Walker
Abstract/Introduction:
An investigation of re-calibration results of metal-sheathed standard platinum resistance thermometer (SPRT) and fused silica-sheathed SPRTs was reported. The performance of metal-sheathed SPRTs could be as good as that of fused-sheathed SPRTs if the user could take care it very well. However, in fact, the long-term stability of metal-sheathed SPRTs is generally worse than that of fusesilica sheathed SPRTs due to the users carelessness. The investigation results were discussed based on possible effects due to the sensor contamination, platinum oxidation, and mechnical shock, etc. To reduce calibration uncertainty and improve calibration reliability, two simple methods are introduced.
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Document ID:
633D79CF
Common Problems In Achieving Maximum Performance From Dry-Well Thermometer Calibrators
Author(s): Mike Hirst
Abstract/Introduction:
Typical specifications for dry-well thermometer calibrators may not provide all the uncertainty information the users need to know. This paper defines other important criteria for making accurate thermometer calibrations using dry-well or dry-block calibrators including stability, radial uniformity, axial uniformity, hysteresis, immersion depth, differences in block loading, use of external references, etc. Examples are provided along with information on how measurements can be made and used.
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Document ID:
14059529
Uv Radiometry At Synchrotron Ultraviolet Radiation Facility Surf( III)
Author(s): Ping-Shine Shaw, Zhigang Li
Abstract/Introduction:
Blackbody radiation and synchrotron radiation are the only two known sources of absolutely calculable radiation. Knowledge of a few simple parameters (thermodynamic temperature and spectral emissivity for a blackbody storage ring electron energy, magnetic field and circulating current for synchrotron radiation) completely determine the spectral and spatial distribution of radiation emitted by these sources, making them suitable as absolute radiometric standards.
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Document ID:
4BC255CB
Metrology Requirements For The Measurement Of Solar Irradiance And Its Variation
Author(s): William E. Mcclintock, Thomas N. Woods, Frank G. Eparvier
Abstract/Introduction:
Accurate measurement of solar XUV-MUV radiation and its variation is essential for understanding the energy input to the earths atmosphere. Solar EUV-MUV irradiance varies a factor of 2 to only 1%, respectively, on 11-year solar cycle timescales with 27-day solar rotation variations that are about a factor of 3 smaller. XUV variability on solar cycle timescales is not well characterized but in contrast to EUV-MUV wavelengths, XUV emissions can vary by orders of magnitude in hours. Photometers and spectrometers aboard spacecraft have been used to study solar XUV-MUV radiation and its variations. These devices use Beamline 2 at the Synchrotron Ultraviolet Radiation Facility (SURF) at the National Institute for Standards and Technology (NIST) located in Gathersburg Md. for their primary preflight calibrations.
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Document ID:
0F1DCC4E
Methods For Considering Correlation In Uncertainty Evaluation
Author(s): Manfred Kochsiek, Bernd Siebert
Abstract/Introduction:
Modern uncertainty evaluation is based on both the knowledge about the measuring process and the input quantities contributing to the measurement result 1. Very often, two or more of the input quantities are not independent from each other. The combined uncertainty for the sum or the product of correlated quantities is enhanced and that for the difference or ratio is decreased by such correlation. In everyday practice, however, correlation is often ignored since the relevant uncertainty documents do not provide ready-for-use procedures for identifying and quantifying correlation. The paper provides practical techniques for identifying and quantifying correlation in measurements. Based on a systematic modelling procedure 2, a concept is presented that allows to easily include correlation in the measurement model and to properly estimate correlation coefficients or correlated fractions of the related input quantities either from existing (statistical) data or from other (non-statistical) knowledge 3. Three possible ways to take correlation into consideration when evaluating measurement uncertainty are described and discussed: Resolving correlation by introducing known dependencies on another (third) quantity, the classical way of Gaussian uncertainty propagation and introducing so-called auxiliary quantities representing the correlated fraction of two or more quantities.
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Document ID:
1813B472
Measurement Risk Analysis Methods With Multiple Test Points
Author(s): Dennis Jackson
Abstract/Introduction:
The analytical description of a calibration scenario involving a single test point is reasonably challenging. Describing measurement risk (the probability of making a wrong test decision), the effect of guard bands, or the choice of a calibration interval for a single test point requires the use of multiple integrals and esoteric mathematical models. A great deal of effort has been expended in the analytical metrology community in developing and publicizing these single test point methods.
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Document ID:
BDE40634
Covariance And Correlation Demystified, Part 2
Author(s): Ricardo A. Nicholas
Abstract/Introduction:
Covariance and correlation can be somewhat of a mystery to evaluators of measurement uncertainty. Covariance, in particular, appears to be the most enigmatic, and therefore the least likely to be used. That need not be the case for those willing to learn or recall a few simple statistical theorems and study a small number of examples. A minimal mastery of them is a prerequisite to achieving a well-rounded competency in measurement uncertainty evaluation. This paper is a continuation and expansion of Covariance and Correlation Demystified, Part 1 1.
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Document ID:
1BB2A65B
Determination Of Environmental Factors Of Pressure Transducers In Cryogenic Environment
Author(s): Zhijie Zhang, Jing Zu, Anshi Chen, Zhigang Yang
Abstract/Introduction:
Pressure transducers are generally calibrated in room temperature. But in an embedded measurement, these transducers often work at very low temperatures. The paper describes a way of calibrating pressure transducers in cryogenic environment. Theoretical and experimental analysis shows that the calibration method is useful and effective. As a result, the environmental factors of pressure transducers in cryogenic environment can be determined. A method for correcting the measurement data is also given.
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Document ID:
5AEF7400
New Concept Dynamic Testing And Calibration Techniques
Author(s): Jing Zu, Zhijie Zhang, Anshi Chen, Dongxing Pei, Peng Xu
Abstract/Introduction:
A definition of new concept dynamic testing and some calibration techniques are presented. The new concept dynamic testing refers to a real-time measurement of dynamic parameters with main part of testing systems located within the object being tested or in the same practical environment. A set of mathematical expressions (i.e. the conditional functions) for dynamic testing is described. Since the performance of testing systems in new concept dynamic testing is strongly affected by the environment forces, general calibration methods are virtually not applicable. The paper presents three layers of calibration techniques: calibrations in simulated application environment, calibrations of environment factors, and tracing calibration of dynamic parameters (also called quasi-d calibration). The last one is useful in many applications.
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Document ID:
5BEE9B21
Correction Of Dynamic Parameters In Measurement Systems
Author(s): Zhijie Zhang, Jing Zu, Anshi Chen, Hongmian Du
Abstract/Introduction:
A generalized method for correcting dynamic characteristics of measurement systems is presented to reduce dynamic errors. The cause of dynamic errors is the sensors frequency response limitation. One way of solving this problem is to make use of deconvolution. Since the problem is ill-conditioned, a small uncertainty in the measurement will cause large deviation in reconstructed signals. The amplified noise has to be suppressed at the sacrifice of biasing in estimation. In this paper, the problem of dynamic characteristics correction is taken as solving stabilized solutions of Fredholm integral equations. Simulation result shows the validity of the method. A practical application of the method in dynamic calibration and data processing are described.
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Document ID:
7220827F
Some Limitations In Uncertainty Evaluation
Author(s): Henrik S. Nielsen
Abstract/Introduction:
Uncertainty budgets are receiving increasing attention not only from accredited laboratories, but from the metrology community at large. Often uncertainties are given with three or more significant digits, indicating that the uncertainty has been determined to within one percent or better, but how accurately can uncertainty be estimated? The paper explores the capabilities of common statistical techniques as well as some of the tools given in the Guide to the Expression of Uncertainty in Measurement. As it turns out, these fundamental building blocks impose some very significant limitations on the uncertainty.
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Document ID:
3C591E30
From NIST To The Engine: Flow Measurement Traceability As It Applies To The Automobile
Author(s): Richard W. Caron
Abstract/Introduction:
In order to meet the government regulations regarding fuel economy and tailpipe emissions, many of todays automotive manufacturers are using mass air flow sensors (MAFS) to accurately measure the intake air flow into their internal combustion and diesel engines. Visteon Corporation designs, develops and manufactures mass air flow sensors and engine air induction systems (AIS). In order to design, develop and manufacture these products, flow testing is a necessity. At various steps in the development and manufacturing processes, air flow rates must be accurately set and measured. Visteon has designed and manufactured flow test stands to meet these accuracy and set point requirements.
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Document ID:
CAEAF841
Legal And Technical Requirements For Time And Frequency Metrology
Author(s): Michael A. Lombardi
Abstract/Introduction:
Who needs time and frequency? This paper answers that question by discussing the technologies and applications that rely on precise time and frequency, and exploring their legal and technical requirements for measurement uncertainty. The technologies and applications discussed include financial markets, the wired and wireless telephone networks, radio and television broadcast stations, the electrical power grid, and radionavigation systems. The paper also discusses legal requirements for everyday metrology, including wristwatches, commercial timing devices, and radar devices used by law enforcement officers.
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Document ID:
796461A4
The Evolution And Application Of Technical Risk Management Within The United States Navy
Author(s): Michael A. Wheeler
Abstract/Introduction:
This research examines how technical risk management has evolved throughout the Department of the Navy (DoN) and to what extent acquisition programs have implemented best practice methods and techniques. A sample of DoN program managers, risk managers, and other acquisition professionals was surveyed to determine attitudes on technical risk management and what fundamental methods are being applied. Survey data was also collected to determine what impact Department of Defense (DoD) and DoN technical risk guidance has had on the acquisition community and what guidance documents are being used. For cases where best-in-class technical risk management methods and techniques have not been applied, this research offers some potential solutions.
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Document ID:
F814371E
Advanced Quantitative Schedule Risk Analysis
Author(s): David T. Hulett
Abstract/Introduction:
Quantitative schedule risk analysis is becoming acknowledged by many project-oriented organizations as a way to improve project on-time performance. It is included in the international standard, the PMBOK Guide 1. By now many project managers and executives know that a good critical path method (CPM) schedule will not provide even the most likely completion date and may not indicate as critical the path the ultimately delays the project.
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Document ID:
1561B4E2