scholarly journals Decision Tree for Key Comparisons

2021 ◽  
Vol 126 ◽  
Author(s):  
Antonio Possolo ◽  
Amanda Koepke ◽  
David Newton ◽  
Michael R. Winchester
Keyword(s):  
Decision Tree ◽  
Working Group ◽  
Statistical Tests ◽  
Full Range ◽  
Key Comparisons ◽  
Inorganic Analysis ◽  
Metrology In Chemistry ◽  
Measurement Results ◽  
Working Groups ◽  
Degrees Of Equivalence

This contribution describes a Decision Tree intended to guide the selection of statistical models and data reduction procedures in key comparisons (KCs). The Decision Tree addresses a specific need of the Inorganic Analysis Working Group (IAWG) of the Consultative Committee (CC) for Amount of Substance, Metrology in Chemistry and Biology (CCQM), of the International Committee for Weights and Measures (CIPM), and it is likely to address similar needs of other working groups and consultative committees. Because the portfolio of KCs previously organized by the CCQM-IAWG affords a full range of opportunities to demonstrate the capabilities of the Decision Tree, the majority of the illustrative examples of application of the Decision Tree are from this working group. However, the Decision Tree is widely applicable in other areas of metrology, as illustrated in examples of application to measurements of radionuclides and of the efficiency of a thermistor power sensor. The Decision Tree is intended for use after choices will have been made about the measurement results that qualify for inclusion in the calculation of the key comparison reference value (KCRV), and about the measurement results for which degrees of equivalence should be produced. Both these choices should be based on substantive considerations, not on purely statistical criteria. However, the Decision Tree does not require that the measurement results selected for either purpose be mutually consistent. The Decision Tree should be used as a guide, not as the sole and autonomous determinant of the model that should be selected for the measurement results obtained in a KC, or of the procedure that should be employed to reduce these results. The scientists running the KCs ultimately have the freedom and responsibility to make the corresponding choices that they deem most appropriate and that best fit the purpose of each KC. The Decision Tree involves three statistical tests, and comprises five terminal leaves, which correspond to as many alternative ways in which the KCRV, its associated uncertainty, and the degrees of equivalence (DoEs) may be computed. This contribution does not purport to suggest that any of the KCRVs, associated uncertainties, or DoEs, presented in previously approved final reports issued by working groups of the CCs should be modified. Neither do the alternative results question existing, demonstrated calibration and measurement capabilities (CMCs), nor do they support any new CMCs.

scholarly journals The measurements results adjustment by the Least Square Method

2021 ◽  
Vol 1 ◽  
pp. 1-8
Author(s):  
Oleksandr Samoilenko ◽  
Yurii Kuzmenko
Keyword(s):  
Reference Value ◽  
Least Square Method ◽  
Systematic Errors ◽  
Least Square ◽  
Key Comparisons ◽  
System Of Equations ◽  
The Third ◽  
Measurement Results ◽  
Free Case ◽  
Degrees Of Equivalence

The method for processing of the measurement results obtained from Comite International des Poids et Measures (CIPM) Key, Regional Metrology Organizations (RMO) or supplementary comparisons, from the proficiency testing by interlaboratory comparisons and the calibrations is proposed. It is named by authors as adjustment by least square method (LSM). Additive and multiplicative parameters for each measuring standard of every particular laboratory will be the results of this adjustment. As well as the parameters for each artifact. The parameters of the measurements standards are their additive and multiplicative degrees of equivalence from the comparison and the estimations of the systematic errors (biases) from calibrations. The parameters of the artifacts are the key comparisons reference value from the comparison and the assigned quantity values from the calibrations. The adjustment is considered as a way to solving a problem of processing the great amount of homogeneous measurements with many measuring standards at a different comparison levels (CIPM, RMO or supplementary), including connected problems. Four different cases of the adjustments are considered. The first one is a free case of adjustment. It was named so because of the fact that none of participants has any advantage except their uncertainties of measurements. The second one is a fixed case of adjustment. Measuring results of RMO and supplementary comparisons are rigidly linked to additive and multiplicative parameters of measuring standards of particular laboratories participated in CIPM key comparisons. The third one is a case of adjustment with dependent equations. This one is not so rigidly linked of the new comparisons results to previous or to some other comparisons as for fixed case. It means that the new results of comparisons are influenced by the known additive and multiplicative parameters and vice versa. The fourth one is a free case of adjustment with additional summary equations. In that case certain checking equations are added to the system of equations. So, the sum of parameters multiplied by their weights of all measurement standards for particular laboratories participated in comparisons should be equal to zero.

Think Tanks in East Asia in Need of More Cooperation and More Networking: NEAT after its Ten Years

2012 ◽  
Vol 04 (03) ◽  
pp. 91-96
Author(s):  
John WONG
Keyword(s):  
East Asia ◽  
Working Group ◽  
Regional Cooperation ◽  
Process Research ◽  
Think Tanks ◽  
Relevant Research ◽  
The Past ◽  
Research Institutes ◽  
Working Groups ◽  
Important Progress

NEAT is a loosely constituted regional scheme under the ASEAN plus Three (APT) framework. Its main objectives are to promote exchange among APT scholars and research institutes in the region, and to promote relevant research that can facilitate the APT regional cooperation process. Research is done through organising Working Groups. NEAT has made important progress in the past 10 years. To grow and expand in future, it will have to improve on its networking function and strengthen its Working Group mechanism.

scholarly journals The SISAL database: a global resource to document oxygen and carbon isotope records from speleothems

2018 ◽  
Author(s):  
Kamolphat Atsawawaranunt ◽  
Laia Comas-Bru ◽  
Sahar Amirnezhad Mozhdehi ◽  
Michael Deininger ◽  
Sandy P. Harrison ◽  
...  
Keyword(s):  
Working Group ◽  
Climate Models ◽  
Full Range ◽  
Global Changes ◽  
Sufficient Information ◽  
Data Set ◽  
Oxygen And Carbon Isotope ◽  
Cave System ◽  
Out Of Sample ◽  
Age Model

Abstract. Stable isotope records from speleothems provide information on past climate changes, most particularly information that can be used to reconstruct past changes in precipitation and atmospheric circulation. These records are increasingly being used to provide “out-of-sample” evaluations of isotope-enabled climate models. SISAL (Speleothem Isotope Synthesis and Analysis) is an international working group of the Past Global Changes (PAGES) project. The working group aims to provide a comprehensive compilation of speleothem isotope records for climate reconstruction and model evaluation. The SISAL database contains data for individual speleothems, grouped by cave system. Stable isotopes of oxygen and carbon (δ18O, δ13C) measurements are referenced by distance from the top or youngest part of the speleothem. Additional tables provide information on dating, including information on the dates used to construct the original age model and sufficient information to assess the quality of each data set and to erect a standardized chronology across different speleothems. The metadata table provides location information, information about the full range of measurements carried out on each speleothem and information about the cave system that is relevant to the interpretation of the records, as well as citations for both publications and archived data. The compiled data are available at http://dx.doi.org/10.17864/1947.139.

Degrees of equivalence across key comparisons in gas analysis

Metrologia ◽  
2003 ◽  
Vol 40 (2) ◽  
pp. 18-23 ◽  
Author(s):  
Adriaan M H van der Veen ◽  
Maurice G Cox
Keyword(s):  
Gas Analysis ◽  
Key Comparisons ◽  
Degrees Of Equivalence

Measurement Uncertainty

2007 ◽  
Author(s):  
D. Brynn Hibbert
Keyword(s):  
Measurement Uncertainty ◽  
Uncertainty Budget ◽  
Test Material ◽  
Metrology In Chemistry ◽  
Energy Agency ◽  
Long Run ◽  
Measurement Results ◽  
Trading Partners ◽  
History Of ◽  
Student’S T

One of the great revolutions in metrology in chemistry has been the understanding of the need to quote an appropriate measurement uncertainty with a result. For some time, a standard deviation determined under not particularly well-defined conditions was considered a reasonable adjunct to a measurement result, and multiplying by the appropriate Student’s t value gave the 95% confidence interval. But knowing that in a long run of experiments repeated under identical conditions 95% of the 95% confidence intervals would include the population mean did not answer the fundamental question of how good the result was. This became evident as international trade burgeoned and more and more discrepancies in measurement results and disagreements between trading partners came to light. To determine if two measurements of ostensibly the same measurand on the same material give results that are equivalent, they must be traceable to the same metrological reference and have stated measurement uncertainties. How to achieve that comparability is the subject of this chapter and the next. When making a chemical measurement by taking a certain amount of the test material, working it up in a form that can be analyzed, calibrating the instrument, and performing the measurement, analysts understand that there will be some doubt about the result. Contributions to uncertainty derive from each step in the analysis, and even from the basis on which the analysis is carried out. An uncertainty budget documents the history of the assessment of the measurement uncertainty of a result, and it is the outcome of the process of identifying and quantifying uncertainty. Although the client may only receive the fruits of this process as (value ± expanded uncertainty), accreditation to ISO/IEC 17025 requires the laboratory to document how the uncertainty is estimated. Estimates of plutonium sources highlight the importance of uncertainty. The International Atomic Energy Agency (IAEA) estimates there are about 700 tonnes of plutonium in the world. The uncertainty of measurement of plutonium is of the order of 0.1%, so even if all the plutonium were in one place, when analyzed the uncertainty would be 700 kg (1000 kg = 1 tonne). Seven kilograms of plutonium makes a reasonable bomb.

scholarly journals 29. Stellar Spectra

1970 ◽  
Vol 14 (1) ◽  
pp. 319-329
Author(s):  
M. W. Feast ◽  
Y. Fujita ◽  
M. K. V. Bappu ◽  
G. Herbig ◽  
L. Houziaux ◽  
...  
Keyword(s):  
Mass Loss ◽  
Working Group ◽  
White Dwarfs ◽  
Vice President ◽  
Stellar Atmospheres ◽  
High Dispersion ◽  
Stellar Rotation ◽  
Stellar Spectra ◽  
Working Groups ◽  
Main Activity

Material for this report was collected by the President, Vice-President and Members of the Organizing Committee. The President is, however, responsible for the form in which the report now appears. A number of special abbreviations in the references are explained in the report of Committee 27a. In addition, 3rd Harvard = 3rd Harvard-Smithsonian Conference on Stellar Atmospheres (1968). The field of Commission 29 overlaps particularly with those of 9, 27a, 36, 44 and 45 whose reports should be consulted. Since the last IAU meeting 29 has co-sponsored the following meetings: IAU Colloquium No. 4 on Stellar Rotation (Columbus, Ohio, September 1969); IAU Symposium No. 36, Ultraviolet Stellar Spectra and Related Ground-Based Observations (Lunteren, June, 1969); Second Trieste Colloquium, Mass Loss from Stars (September, 1968). We are also co-sponsoring IAU Symposium No. 42 on White Dwarfs to be held in Scotland (August, 1970). The thanks of the commission are due to their representatives on the organizing committees of these meetings. Reports from some working groups are appended. The working group with Commission 44 has not felt it necessary to submit a report (its main activity was the organization of Symposium No. 36). Miss Underhill (Chairman) recommends that the working group on Tracings of High Dispersion Stellar Spectra be dissolved.

8 Years Working of ENTRAP’s Working Group on Non-Destructive Testing of Waste Packages

2001 ◽  
Author(s):  
M. Bruggeman ◽  
P. Van Iseghem ◽  
R. Odoj ◽  
Ch. Lierse von Gostomski ◽  
R. Dierckx
Keyword(s):  
Nuclear Waste ◽  
Information Exchange ◽  
Working Group ◽  
The State ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
European Organisation ◽  
Eu Member States ◽  
Working Groups ◽  
Non Destructive

Abstract ENTRAP is a European organisation grouping nuclear waste quality checking laboratories from different EU member states. The main objectives of ENTRAP are information exchange and harmonisation between the laboratories. ENTRAP works on different aspects of quality checking of nuclear waste packages. The working items are treated in different working groups and one of these working groups is WGA, dealing with non-destructive assay techniques for waste packages. This paper discusses the main achievements made by WGA, and gives a summary of the state-of-the-practice of assay techniques used for quality checking of nuclear waste packages in the different member laboratories.

scholarly journals Inter-Division IV/V WG on Chemically Peculiar and Related Stars

2005 ◽  
Vol 1 (T26A) ◽  
pp. 243-243
Author(s):  
Werner W. Weiss
Keyword(s):  
Working Group ◽  
General Will ◽  
Chemically Peculiar ◽  
Working Groups

A meeting of the IAU Working Group on Chemically Peculiar and Related Stars was held in Sydney on July 16th, 2003. The focus of the business session was on possible effects on our WG due to plans for restructuring the IAU. Working Groups are to be evaluated every 3 years and in general, will be limited to a period of 3 or 6 years.

THE IPIECA OIL SPILL WORKING GROUP 20:20 VISION REFLECTIONS AND PROJECTIONS ON OUR 20TH ANNIVERSARY

2008 ◽  
Vol 2008 (1) ◽  
pp. 1093-1095
Author(s):  
Bernie Bennett ◽  
Yvette Osikilo
Keyword(s):  
Oil Spill ◽  
Working Group ◽  
Oil Pollution ◽  
Full Range ◽  
Petroleum Industry ◽  
Environmental Conservation ◽  
International Convention ◽  
Oil Spill Response ◽  
20Th Anniversary ◽  
The Impact

ABSTRACT The International Petroleum Industry Environmental Conservation Association (IPIECA) Oil Spill Working Group (OSWG) is celebrating its 20th anniversary. Its mission has been, through education, training and awareness initiatives, to enhance the state of preparedness and response to marine oil spill incidents in priority coastal locations around the world. Its programme is carried out in close cooperation with the International Maritime Organization (IMO) and operates within the context of the International Convention on Oil Pollution Preparedness, Response and Cooperation (OPRC), 1990. The OSWG is made up of oil spill managers and specialists from IPIECA member companies and associations, supported by invited representatives from other organisations in the oil spill response community. It aims to ensure that the full range of industry interests is adequately reflected in its work programme. Coordination between these industry-based organisations and the IMO remains an essential ingredient in the success of the OSWG programme This paper reviews the main activities and achievements of the IPIECA OSWG over the last 20 years and attempt to illustrate and measure the impact of its work on global oil spill preparedness. We then hypothesize as to how the work of the IPIECA OSWG might develop over the next 20 years, which could serve as future strategic/planning guidance.

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