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VALIDATION AND VERIFICATION OF MEASUREMENT METHODS IN CLINICAL DIAGNOSIS

The article investigates and analyzes the validation and verification of measurement methods in the clinical diagnostic laboratory. The content and features of validation and verification are revealed. Measurement methods are considered in detail. Each direction of validation and verification of measurement methods is analyzed. The difference between validation and verification is substantiated. Measuring systems are increasingly used in the laboratories of the clinical sector. This means that the responsibility for validation lies mainly with the manufacturer.

UNCERTAINTIES OF THE ESTIMATORS AND PARAMETERS OF DISTRIBUTION IN MEASUREMENTS WITH MULTIPLY OBSERVATIONS

The article shows that the commonly used method of estimating the Type A uncertainty of measurements based on the standard deviation of estimators of population parameters does not meet the definition of uncertainty. For correct determination of the standard uncertainty, it is necessary to use the distribution of the corresponding population parameter at the values of population estimators determined from the experiment but not the probability distribution of the estimator.

Methodology for Determining the Response Time of Thermo Transducers for Measuring the Temperature of Gas Flows

Gas flow temperature is an important parameter of the process, determines the quantitative and qualitative indicators of the original product, the presence of defects, the state of technological equipment, as well as the safety of the process. Therefore, its measurement must be carried out continuously, with high accuracy, low inertia and high reliability, since the information signal about the value of temperature is used in information-measuring systems and automatic control and regulation systems.

Equation of Arithmetic Mean Deviation of Roughness Profile

In order to improve the accuracy of gas flowrate measurement by means of the differential pressure flowmeters, it is necessary to apply equations for determination of coefficients of gas flow equation, which would provide the lowest total relative expanded uncertainty of calculation, and to increase the accuracy of input values measurement in real time. One of these values is the arithmetic mean deviation of roughness profile of pipe internal surface. The equation for calculating the arithmetic mean deviation of roughness profile of pipe internal surface in real time was obtained.

ENSURING METROLOGICAL RELIABILITY OF MEASUREMENTS

The  article proposes  an  approach  to  the  research of  the metrological  reliability  of measurements  taking  into account the conditions and operating modes of measuring equipment, based on the intermediate control of the standard deviation of  the measurement  results.  The  above  approach  is  relevant  because  it  allows  laboratories  to  reasonably  set  the  recalibration intervals  of  measuring  equipment  based  on  the  control  of  standard  deviations.  The  requirement  for  reasonable  setting  of recalibration intervals for measuring instruments is a common worldwide

DEPENDENCE OF DISPERSION OF MEASUREMENT RESULTS ON DURATION OF MEASUREMENT

The results of statistical measurements of the resistance of the metal film resistor are given below. The analysis of the dependencies of the standard deviation on the number of measurements σR(N)envisages a tendency of  raising σR with the number of measurements. It indicates that the obtained results are not independent since fluctuations of them are not of “white” noise type. The dependence of the standard deviation of measurement results onN confirms the results of other studies.

ANALYSIS OF REQUIREMENTS FOR EQUIPMENT AND TECHNIQUES ACCORDING TO ISO/IEC 17025:2017

It is important to carry out metrological confirmation of the used measuring equipment in order to obtain reliable measurement results during the conformity assessment of products. Assessment of the metrological confirmation of the measuring equipment confirms its conformity with the given measuring task. For proper performance of this task it is necessary to have an appropriate measurement  technique.

HISTORICAL PERSONALITY IN THE FIELD OF GALychyna METROLOGY – PROFESSOR DOCTOR J. x. LIESGANIG (1719–1799)

In 2019, 100 years since the founding of the Department of Information and Measurement Technologies of the Lviv  Polytechnic  National  University,  there  is  an  urgent  need  to  look  back  in  the  historical  perspective  and  analyze  the contribution of certain historical figures to the development of engineering thought and the principles of metrology in the areas of Western Ukraine  and,  in particular,  in  the  territories of Galychyna.

ANALYSIS OF THE MEASUREMENT QUALITY INDEXES

The article focuses on the main problems of methodology of the measurement quality evaluation in the context of introduction into metrological practice of the International Dictionary of Metrology VIM 3. The generalized definition of the notion of measurement quality is given. A separate analysis of measurement quality indexes as a process and quality indexes of measurement result as a product of this process is carried out.

THE EFFECT OF RANDOM DEVIATIONS ON UNCERTAINTY OF EXTREME OBSERVATIONS

An attention is considered to analysis of instrumental component of result’s uncertainty. While production control in industry, the mentioned component for concrete measuring instrument with the concrete measurement results has to be determined and analyzed. Important is the question of random impacts effect on to uncertainty of extreme (minimum or maximum) observations.