scholarly journals New strain gauge-based torque reference chain offering smallest measurement uncertainties

2019 ◽  
Author(s):  
André Schäfer
Keyword(s):  
Automotive Industry ◽  
Strain Gauge ◽  
Metrological Traceability ◽  
Traceability Chain ◽  
Metrological Infrastructure ◽  
Measurement Uncertainties ◽  
Reference Sensor

New measurement approaches for mechanical quantities based on strain gauge technology offer one feature above all else: the possibility to realize smallest measurement uncertainties. This is particularly important for metrological infrastructure, i.e. realization of metrological traceability chain to support applications in aerospace or in automotive industry. Achievements toward smaller measurement uncertainties are shown by realization of a novel torque reference sensor TN with improved usability for inter-laboratory comparisons in combination with a surprisingly compact precision amplifier called Quantum MX238B.

scholarly journals Documenting metrological traceability as intended by ISO 15189:2012: A consensus statement about the practice of the implementation and auditing of this norm element

2019 ◽  
Vol 57 (4) ◽  
pp. 459-464 ◽  
Author(s):  
Marc Thelen ◽  
Florent Vanstapel ◽  
Pika Meško Brguljan ◽  
Bernard Gouget ◽  
Guilaine Boursier ◽  
...  
Keyword(s):  
Metrological Traceability ◽  
Measurement Procedure ◽  
Medical Laboratory ◽  
Clinical Samples ◽  
End User ◽  
Worst Case ◽  
Iso 15189 ◽  
Value Assignment ◽  
Traceability Chain ◽  
Medical Laboratories

Abstract ISO15189:2012 requires medical laboratories to document metrological traceability of their results. While the ISO17511:2003 standard on metrological traceability in laboratory medicine requires the use of the highest available level in the traceability chain, it recognizes that for many measurands there is no reference above the manufacturer’s selected measurement procedure and the manufacturer’s working calibrator. Some immunoassays, although they intend to measure the same quantity and may even refer to the same reference material, unfortunately produce different results because of differences in analytical selectivity as manufacturers select different epitopes and antibodies for the same analyte. In other cases, the cause is the use of reference materials, which are not commutable. The uncertainty associated with the result is another important aspect in metrological traceability implementation. As the measurement uncertainty on the clinical samples is influenced by the uncertainty of all steps higher in the traceability chain, laboratories should be provided with adequate and appropriate information on the uncertainty of the value assignment to the commercial calibrators that they use. Although the between-lot variation in value assignment will manifest itself as part of the long-term imprecision as estimated by the end-user, information on worst-case to be expected lot-lot variation has to be communicated to the end-user by the IVD provider. When laboratories use ancillary equipment that potentially could have a critical contribution to the reported results, such equipment needs verification of its proper calibration and criticality to the result uncertainty could be assessed by an approach based on risk analysis, which is a key element of ISO15189:2012 anyway. This paper discusses how the requirement for metrological traceability as stated in ISO15189 should be met by the medical laboratory and how this should be assessed by accreditation bodies.

Standardization of 18F and its use for the Romanian PET metrological traceability chain assurance

2014 ◽  
Vol 87 ◽  
pp. 14-18 ◽  
Author(s):  
M. Sahagia ◽  
R. Ioan ◽  
A. Luca ◽  
A. Antohe ◽  
C. Ivan ◽  
...  
Keyword(s):  
Metrological Traceability ◽  
Traceability Chain

Traceability in laboratory medicine: a global driver for accurate results for patient care

2017 ◽  
Vol 55 (8) ◽  
pp. 1100-1108 ◽  
Author(s):  
Graham H. Beastall ◽  
Nannette Brouwer ◽  
Silvia Quiroga ◽  
Gary L. Myers
Keyword(s):  
Reference Materials ◽  
Action Plan ◽  
Metrological Traceability ◽  
Laboratory Medicine ◽  
Geographical Differences ◽  
Traceability Chain ◽  
Stakeholder Groups ◽  
Universal Approach ◽  
Global Coordination ◽  
International Experts

AbstractLaboratory medicine results influence a high percentage of all clinical decisions. Globalization requires that laboratory medicine results should be transferable between methods in the interests of patient safety. International collaboration is necessary to deliver this requirement. That collaboration should be based on traceability in laboratory medicine and the adoption of higher order international commutable reference materials and measurement procedures. Application of the metrological traceability chain facilitates a universal approach. The measurement of serum cholesterol and blood HbA1cserve as examples of the process of method standardization where an impact on clinical outcomes is demonstrable. The measurement of plasma parathyroid hormone and blood HbA2 serve as examples where the current between-method variability is compromising patient management and method standardization and/or harmonization is required. Challenges to the widespread adoption of traceability in laboratory medicine include the availability of reference materials and methods, geographical differences, the use of variable units, complex analytes and limited global coordination. The global collaboration requires the involvement of several different stakeholder groups ranging from international experts to laboratory medicine specialists in routine clinical laboratories. A coordinated action plan is presented with actions attributable to each of these stakeholder groups.

HANDLING OF CORRELATIONS OF SPECTRAL QUANTITIES IN TRACEABILITY CHAIN – BASICS FOR A PYTHON-BASED ANALYSIS FRAMEWORKE

2021 ◽  
Author(s):  
Philipp Schneider ◽  
Thorsten Gerloff ◽  
Armin Sperling
Keyword(s):  
Measurement Uncertainty ◽  
Test Methods ◽  
Correlated Data ◽  
Test Laboratory ◽  
Spectral Irradiance ◽  
Analysis Framework ◽  
Major Goal ◽  
Traceability Chain ◽  
Measurement Uncertainties

In this contribution a framework is presented that aims to help for handling correlations within measurement uncertainty calculations for spectral quantities. Taking correlations for spectral quantities into account is necessary as they directly influence the measurement uncertainties especially for integral quantities. Therefore, determination of correlations within traceability chains at national metrology institutes (NMIs) and disseminations of correlated data to test laboratory level is encouraged and a major goal of the EMPIR project 19NRM02 “Revision and extension of standards for test methods for LED lamps, luminaires and modules” (RevStdLED). The presented python-based analysis framework is used in photometry and spectroradiometry at PTB to calculate the results and associated measurement uncertainty for spectral irradiance, spectral irradiance responsivity and luminous responsivity based on spectral calibrations.

Discussion on the Classification Criteria of Measurement System Level

2021 ◽  
Author(s):  
Yi-Ting Chen ◽  
Keyword(s):  
Measurement System ◽  
Metrological Traceability ◽  
Classification Criteria ◽  
System Level ◽  
Traceability Chain ◽  
Measurement Systems ◽  
Primary Measurement ◽  
Measurement Results ◽  
Definition Of

According to the definition of metrological traceability in ISO/IEC Guide 99:2007(VIM 3)[1], people in the metrology field can know the level of the measurement system in the metrological traceability chain by drawing the metrological traceability diagram on the measurement results. However, if someone want to further determine which level the measurement system belongs to, it should be classified as primary measurement system, secondary measurement system, or even other measurement systems. Because the definitions of terms such as primary measurement system, secondary measurement system and other measurement systems are not included in VIM 3[1], there’s no clear classification basis for the measurement system level. Therefore, this article will discuss the definitions of terms in VIM 3[1] that are more relevant to the classification of measurement system levels, then try to formulate the classification criteria, supplemented by case studies, and hope to serve as a reference for people in the metrology field when reviewing the measurement system and judging its system level.

scholarly journals Metrological traceability and harmonization of medical tests: a quantum leap forward is needed to keep pace with globalization and stringent IVD-regulations in the 21st century!

2018 ◽  
Vol 56 (10) ◽  
pp. 1598-1602 ◽  
Author(s):  
Christa Cobbaert ◽  
Nico Smit ◽  
Philippe Gillery
Keyword(s):  
21St Century ◽  
Clinical Laboratory ◽  
Metrological Traceability ◽  
Laboratory Medicine ◽  
Test Results ◽  
Medical Test ◽  
Traceability Chain ◽  
Medical Laboratories ◽  
Medical Tests ◽  
Quantum Leap

Abstract In our efforts to advance the profession and practice of clinical laboratory medicine, strong coordination and collaboration are needed more than ever before. At the dawn of the 21st century, medical laboratories are facing many unmet clinical needs, a technological revolution promising a plethora of better biomarkers, financial constraints, a growing scarcity of well-trained laboratory technicians and a sharply increasing number of International Organization for Standardization guidelines and new regulations to which medical laboratories should comply in order to guarantee safety and effectiveness of medical test results. Although this is a global trend, medical laboratories across continents and countries are in distinct phases and experience various situations. A universal underlying requirement for safe and global use of medical test results is the standardization and harmonization of test results. Since two decades and after a number of endeavors on standardization/harmonization of medical tests, it is time to reflect on the effectiveness of the approaches used. To keep laboratory medicine sustainable, viable and affordable, clarification of the promises of metrological traceability of test results for improving sick and health care, realization of formal commitment among all stakeholders of the metrological traceability chain and preparation of a joint and global plan for action are essential prerequisites. Policy makers and regulators should not only overwhelm the diagnostic sector with oversight and regulations but should also create the conditions by establishing a global professional forum for anchoring the metrological traceability concept in the medical test domain. Even so, professional societies should have a strong voice in their (inter-) national governments to negotiate long-lasting public policy commitment and funds for global standardization of medical tests.

Reducing measurement uncertainties of high-pressure gas flow calibrations by using reference values based on multiple independent traceability chains

2018 ◽  
Vol 85 (12) ◽  
pp. 754-763
Author(s):  
Jos van der Grinten ◽  
Henri Foulon ◽  
Arnthor Gunnarsson ◽  
Bodo Mickan
Keyword(s):  
High Pressure ◽  
Gas Flow ◽  
Weighted Average ◽  
Reference Value ◽  
Polynomial Equation ◽  
Calibration Data ◽  
Traceability Chain ◽  
Uncertainty Sources ◽  
Flow Reynolds Number ◽  
Measurement Uncertainties

Abstract This paper describes the recently updated realization of the harmonized cubic metre for natural gas. It is a procedure based on an intercomparison, that combines the mutually independent traceability chains of four primary laboratories in the field of high-pressure gas flow measurement. The reference value, also called harmonized cubic metre, is the weighted average of at least two laboratories with weighing factors that are inversely proportional to the squared uncertainties of the calibration results. This results in lower uncertainties for the laboratories as long as the stochastic contributions (Type A) to the overall measurement uncertainties are significantly smaller than the uncertainties arising from the traceability chain (Type B). This condition is fulfilled in practice as traceability uncertainties are at least a factor ten greater than the other uncertainty sources. When evaluating the data of intercomparisons, curve fitting is used for the representation of the calibration data. A polynomial equation of maximum four degrees, expressed in the logarithm of the flow Reynolds number, proves to be the optimum choice for fitting the calibration curve of the turbine gasmeters.

scholarly journals Calibration of a modular trap detector system towards a new realisation of the luminous intensity unit

2022 ◽  
Vol 2149 (1) ◽  
pp. 012008
Author(s):  
Philipp Schneider ◽  
Saulius Nevas ◽  
Detlef Lindner ◽  
Lutz Werner ◽  
Ulrike Linke ◽  
...  
Keyword(s):  
Major Part ◽  
Detector System ◽  
Spectral Irradiance ◽  
Luminous Intensity ◽  
Traceability Chain ◽  
Trap Detector ◽  
Individual Calibration ◽  
Measurement Uncertainties ◽  
The Individual ◽  
First Time

Abstract A modular photometric trap detector system has recently been developed at Physikalisch-Technische Bundesanstalt (PTB). All parts of the detector are now completely calibrated. The new planned traceability chain for the realisation of luminous intensity unit can therefore be established for the first time. This contribution shows the results of the individual calibration steps including the associated measurement uncertainties and correlations. A major part of the calibrations along the traceability chain is done at the upgraded measurement setup TULIP (TUnable Lasers In Photometry). The improvements of the TULIP setup are presented and the effects on the measurement uncertainty are shown. The result of the first complete calibration according to the new traceability chain is compared to previous calibration results both in terms of spectral irradiance responsivity and luminous responsivity. The further steps required towards implementing the new traceability chain and the possible implications are discussed.

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