scholarly journals Determination of measurement uncertainty as a necessary condition confirming the reliability of measurement results

Rail Vehicles ◽  
2019 ◽  
pp. 39-49
Author(s):  
Joanna Wojtukiewicz
Keyword(s):  
Measurement Uncertainty ◽  
Necessary Condition ◽  
Measurement Results ◽  
Reliability Of Measurement Results

W artykule zawarto najważniejsze zagadnienia związane z wyznaczaniem niepewności pomiaru oraz z przedstawianiem wiarygodnych wyników pomiarów. Przedstawiono m.in. najważniejsze pojęcia dotyczące niepewności pomiaru, wymagania normatywne, źródła, cel oraz metody wyznaczania niepewności pomiaru. Artykuł zawiera również odniesienie do czynności metrologicznych wykonywanych w Laboratorium Badań Pojazdów Szynowych w celu spełnienia przedstawionych wymagań.

scholarly journals Determination of probe non-linearity and error due to measurement position for direct measurement type of gauge block comparator and its measurement uncertainty

2021 ◽  
Vol 2145 (1) ◽  
pp. 012060
Author(s):  
A Pringkasemchai ◽  
J Wongsaroj ◽  
K Mongkolsuttirat
Keyword(s):  
Measurement Uncertainty ◽  
Direct Measurement ◽  
Comparative Method ◽  
Standard Uncertainty ◽  
Simple Linear Regression ◽  
Measuring Range ◽  
Gauge Block ◽  
Measurement Results ◽  
Accuracy Of Measurement

Abstract The non-linearity of probes is one of the important components in gauge block calibration by the mechanical comparative method of two gauges blocks at the same nominal length. However, an advanced method for gauge block calibration is a mechanical direct measurement method of two gauge blocks showing the greatest difference in nominal length of 25 mm. This method uses a special probe based on the interferential scanning principle to produce the signals to measure the displacement. In this paper, non-linearity and error due to measurement position were investigated as they related to the accuracy of measurement results. The differences in central length of pairs of standard gauge blocks made of steel were measured by optical interferometry with the measurement uncertainty (k=2) 23 nm. Length in the range of 5 μm to 25 mm was used in the experiment. Non-linearity of the probe was evaluated by the simple linear regression model. Various factors such as origin setting point, temperature, and vibration have been analysed. In the preliminary experiment, the non-linearity, position error, repeatability and retrace error over the measuring range 25 mm are 13 nm, -18 nm, 15 nm, and 10 nm respectively. The standard uncertainty of direct measurement type caused by non-linearity is 4 nm.

Evaluation of Measurement Uncertainty for the Determination of MgO in Magnesia Refractories by XRF

2018 ◽  
Vol 768 ◽  
pp. 36-40
Author(s):  
Qing Dan Yuan ◽  
Shi Hua Liu ◽  
Qian Nan Li ◽  
Wei Han
Keyword(s):  
Measurement Uncertainty ◽  
Mathematical Models ◽  
Magnesium Oxide ◽  
Oxide Content ◽  
Refractory Materials ◽  
Melting Method ◽  
X Ray ◽  
Measurement Results ◽  
Synthetic Standard

The method of X-ray fluorescence spectrometry (XRF) for the determination of MgO in magnesia refractories was introduced. The uncertainty of the MgO in refractory materials was analyzed by melting method of XRF. The measurement uncertainty was evaluated, and the related mathematical models was established. The uncertainty of synthetic standard was calculated by the evaluation of the uncertainty of each component standard. And eventually converted to the measurement results to expand the uncertainty. The effects of two melting methods on the uncertainty of magnesium oxide content were compared.

scholarly journals Calculation of Misjudgment Probability for Product Inspection Based on Measurement Uncertainty

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Xiao-huai Chen ◽  
Yin-bao Cheng ◽  
Han-bin Wang ◽  
Hong-li Li ◽  
Zhen-ying Cheng ◽  
...  
Keyword(s):  
Measurement Uncertainty ◽  
Conditional Probability ◽  
Probability Model ◽  
Probability Models ◽  
Estimation Formula ◽  
Sampling Inspection ◽  
Measurement Results ◽  
Absolute Probability ◽  
Selection Of

It is important to research into the misjudgment probability of product inspection based on measurement uncertainty, which is of great significance to improve the reliability of inspection results. This paper mainly focused on total inspection and sampling inspection methods and regarded the misjudgment probability as the index to provide quantitative misjudgment risk results for both producer and consumer sides. Through the absolute probability and the conditional probability model, the estimation formula of the total inspection misjudgment rate is deduced, respectively, and the calculation methods of qualification determination and misjudgment rate of the full inspection results are studied. According to the total inspection misjudgment rate, the methods of misjudgment rate of sampling inspection and qualification determination of measurement results are researched. The misjudgment rate of measurement results is calculated based on the exhaustive method and the Monte-Carlo simulation. The estimation results show that the misjudgment probabilities calculated by absolute probability models can be used as the basis for the selection of the measurement plan for product inspection. The misjudgment probability calculated by conditional probability models is more directly to reflect the risks for both producer and consumer sides, and it prompts inspectors to make decisions more carefully.

New advances in the method validation, extraction methods and measurement uncertainty for the determination of water-soluble hexavalent chromium in hydraulic cement

Talanta ◽  
2021 ◽  
Vol 232 ◽  
pp. 122286
Author(s):  
María Melania Ramírez-Quesada ◽  
Jimmy Venegas-Padilla ◽  
José Pablo Sibaja-Brenes ◽  
Bryan Calderón-Jiménez
Keyword(s):  
Measurement Uncertainty ◽  
Hexavalent Chromium ◽  
Method Validation ◽  
Extraction Methods ◽  
Water Soluble ◽  
Hydraulic Cement

Estimation of uncertainty in olfactometry

2009 ◽  
Vol 59 (7) ◽  
pp. 1409-1413 ◽  
Author(s):  
T. Higuchi
Keyword(s):  
Measurement Uncertainty ◽  
Interlaboratory Comparison ◽  
Collaborative Study ◽  
Estimation Procedure ◽  
Measurement Model ◽  
Standard Uncertainty ◽  
Expanded Uncertainty ◽  
Collaborative Test ◽  
Measurement Results ◽  
Estimation Of Uncertainty

Estimation of uncertainty in odour measurement is essential to the interpretation of the measurement results. The fundamental procedure for the estimation of measurement uncertainty comprises the specification of the measurement process, expression of the measurement model and all influences, evaluation of the standard uncertainty of each component, calculation of the combined standard uncertainty, determination of a coverage factor, calculation of the expanded uncertainty and reporting. Collaborative study such as interlaboratory comparison of olfactometry yields performance indicators of the measurement method including repeatability and reproducibility. Therefore, the use of collaborative test results for measurement uncertainty estimation according to ISO/TS 21748 and ISO 20988 is effective and reasonable. Measurement uncertainty of the triangular odour bag method was estimated using interlaboratory comparison data from 2003 to 2007 on the basis of the simplest model of statistical analysis, and the expanded uncertainty of odour index ranged between 3.1 and 6.7. On the basis of the establishment of the estimation procedure for uncertainty, a coherent interpretation method for the measurement results will be proposed and more effective and practical quality control of olfactometry will be available.

Development of a centralized approach to conducting interlaboratory proficiency tests

2021 ◽  
pp. 428-434
Author(s):  
Светлана Владимировна Габова ◽  
Анастасия Александровна Трусагина ◽  
Михаил Евгеньевич Артёмов
Keyword(s):  
Quality Control ◽  
Control System ◽  
Oil Quality ◽  
Third Party ◽  
Quality Control System ◽  
Proficiency Tests ◽  
Testing Program ◽  
Testing Laboratories ◽  
Measurement Results ◽  
Reliability Of Measurement Results

Важнейшим звеном системы контроля качества нефти являются испытательные лаборатории, от компетентности которых зависит достоверность результатов измерений и эффективность управленческих решений, принимаемых с учетом полученных данных. Одним из способов подтверждения достоверности результатов измерений является проверка квалификации лаборатории посредством ее участия в межлабораторных сличительных (сравнительных) испытаниях (МСИ). В настоящей статье рассмотрены вопросы проведения таких испытаний для лабораторий организаций системы «Транснефть». Описан действующий порядок, предполагающий участие лабораторий в МСИ в регионах своего местонахождения, при этом разработкой и реализацией программы проверки квалификации занимаются сторонние организации - провайдеры МСИ. Такая практика имеет существенные недостатки, не позволяя, в том числе, систематизировать и обобщить результаты МСИ для общей оценки деятельности испытательных лабораторий ПАО «Транснефть». В статье представлен централизованный подход к проведению МСИ в ПАО «Транснефть», устанавливающий единый порядок участия лабораторий в испытаниях с целью осуществления общей оценки квалификации лабораторий, своевременной разработки и реализации предупреждающих и корректирующих мероприятий по улучшению деятельности лабораторий, усовершенствования системы контроля качества нефти на объектах ПАО «Транснефть». The most important link in the oil quality control system are testing laboratories, the competence of which determines the reliability of measurement results and the effectiveness of management decisions based on the data obtained. One way to confirm the validity of measurement results is to verify the laboratory qualifications through its participation in interlaboratory proficiency (comparative) tests (IPT). This article considers the issues of such tests for the laboratories of Transneft system entities. The current procedure is described, which involves the participation of laboratories in the IPT in the regions of their location, while the development and implementation of the proficiency testing program is carried out by third-party IPT provider organizations. This practice has significant drawbacks, not allowing, among other things, to systematize and summarize the results of IPT for an overall assessment of the activities of Transneft PJSC’s testing laboratories. The article presents a centralized approach to conducting IPT in Transneft PJSC, which establishes a unified procedure for the participation of laboratories in tests in order to implement an overall assessment of laboratory qualification, timely development and implementation of preventive and corrective measures to improve the performance of laboratories and improve the oil quality control system at the Transneft PJSC facilities.

scholarly journals UNCERTAINTY OF MEASUREMENT RESULTS IN FUEL ANALYSES

2002 ◽  
Vol 1 (2) ◽  
Author(s):  
Paulo Roberto Guimarães Couto ◽  
Ilse Maria Guilhermino Lemos
Keyword(s):  
Mutual Recognition ◽  
Metrological Reliability ◽  
Uncertainty Of Measurement ◽  
Measurement Results ◽  
Judicial Ruling ◽  
Quality Of Products ◽  
Reliability Of Measurement Results

The result of a measurement serves as a parameter in a variety of applications, such as: the sale of products; the inspection of materials in relation to specifications/ limits set by a standard; providing support for a judicial ruling; improving the specific quality of products; estimating profitability and making comparisons with a view to mutual recognition between metrology laboratories and systems. The aim of this work is to demonstrate the relevance and applications of the ISO GUM 95 in the fuel analyses conducted by the LABCOM at the EQ/UFRJ, presenting results tables and discussions. The paper further discusses the strategic importance of metrological reliability of measurement results and of the actions of a laboratory within the context of the science of metrology in Brazil.

scholarly journals Atmospheric CO2, CH4, and CO with CRDS technique at the Izaña Global GAW station: instrumental tests, developments and first measurement results

2017 ◽  
Author(s):  
Angel J. Gomez-Pelaez ◽  
Ramon Ramos ◽  
Emilio Cuevas ◽  
Vanessa Gomez-Trueba ◽  
Enrique Reyes
Keyword(s):  
Drift Rate ◽  
Inlet Pressure ◽  
Response Functions ◽  
Measurement Results ◽  
Ambient Measurements ◽  
Acceptance Tests ◽  
Term Maintenance

Abstract. At the end of 2015, a CO2/CH4/CO Cavity Ring-Down Spectrometer (CRDS) was installed at the Izaña Global Atmosphere Watch station (Tenerife, Spain) to improve the Izaña Greenhouse gases GAW measurement programme, and to guarantee the renewal of the instrumentation and the long-term maintenance of this programme. We present the results of the CRDS acceptance tests, the processing of raw data applied through novel numerical codes, and the response functions used. Also, the calibration results, the implemented water vapour correction, the target gas injection statistics, the ambient measurements performed from December 2015 to July 2017, and their comparison with other continuous in situ measurements are described. The agreement with other in situ continuous measurements is good most of the time for CO2 and CH4, but for CO is just outside the GAW 2-ppb objective. It seems the disagreement is not produced by significant drifts in the CRDS CO WMO tertiary standards. The main novelties are: 1) determination of a slight CO2 correction that takes into account changes in the inlet pressure/flow rate; 2) detailed justification of the use of virtual tanks to monitor the response function changes in time; 3) drift rate determination for the pressure and temperature sensors located inside the CRDS cavity; 4) novelties in the determination of the H2O correction for CO; and 5) determination and discussion of the origin of the CRDS-flow inlet pressure and H2O dependences.

scholarly journals APPLICATION OF A SCINTILLATION GAMMA-SPECTROMETER FOR DETERMINATION OF RADON CONTENT IN WATER

2021 ◽  
pp. 187-190
Author(s):  
D.А. Hakimov ◽  
I.V. Zhuk ◽  
M.K. Kievets
Keyword(s):  
Water Samples ◽  
Mineral Water ◽  
Experimental Studies ◽  
Gamma Spectrometer ◽  
Scintillation Gamma ◽  
Measurement Results ◽  
Measurable Activity ◽  
Measurement Geometry ◽  
Radon Content

Experimental studies have been carried out to determine the sensitivity of a mobile scintillation gamma-spectrometer to radon-222 in mineral water samples for the selected measurement geometry and the minimum measurable activity of radon-222 in such samples. The measurement results of radon content in mineral water samples obtained using such gamma-spectrometer are presented too.

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