uncertainty

ANALYSIS OF CALORIMETRIC METHOD OF MEASUREMENT OF NATURAL GAS CALORIFIC VALUE

The article considers the current methods of measuring the calorific value of natural gas which are valid in the upto-date gasometry. The procedure for measuring the gross and net volume-basis specific calorific value of natural gas by the calorimetric method is analyzed. It is shown that to increase the accuracy and validity of measurement results, the experiment to determine the values of gross and net volume-basis specific calorific should be performed for at least 5 samples of the investigated gas.

Modeling in the Field of Freight Transportation: Ambivalence of Management Decisions in the Conditions of Quarantine Restrictions and Economic Competition

The study focuses on the ambiguity of management decisions in conditions of economic competition and quarantine restrictions. It is concluded that in the field of freight transportation there are antagonistic interests of the environment in the process of making management decisions by managers of JSC “Ukrzaliznytsia”. The classification of information situations related to the uncertainty of the environment is used, according to which the fifth information situation most closely corresponds to the current situation in the market of transport services.

On the asymptotic output sensitivity problem for a discrete linear systems with an uncertain initial state

This paper studies a finite-dimensional discrete linear system whose initial state $x_0$ is unknown.  We assume that the system is augmented by two output equations, the first one $z_i$ being representing measurements made on the unknown state of the system and the other $y_i$ being representing the corresponding output.  The purpose of our work is to introduce two control laws, both in closed-loop of measurements $z_i$ and whose goal is to reduce asymptotically the effects of the unknown part of the initial state $x_0$.  The approach that we present consists of both th

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.

Processing of the length measuring results during comparisons or calibrations the distance meters and total stations on a field comparator

A method has been developed for the adjustment of the results of measurements of length during calibration of a field comparator for verification (calibration) of distance meters and distance metric parts of total stations. The method of processing the results of comparisons of distance meters to the field comparator using the least squares method (LSM) was also developed on its basis. The additive biases of length measurements by each distance meter are evaluated according to the LSM, as well as the biases that are entered to the results of length measurements by each reflector.

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.

THE STANDARD OF UNIT OF ULTRASONIC PRESSURE IN AQUEOUS MEDIUM

The article analyzes the topicality of the primary standard creation of the ultrasonic pressure unit in water for the frequency  range of 0.5–10.0 MHz  in Ukraine.  Its creation  is predetermined by  the necessity of  the exploited ultrasound medical equipment metrological maintenance as well as for the assessment of compliance with the requirements of the technical regulations for medical products to be exploited.

Guaranteed predictive estimation of solutions of system of differential equations with the Gompertzian dynamics

In this paper, we have introduced a mathematical model to describe processes that grow in time rapidly.  The model has the form of a system of non-linear differential equations with Gompertzian dynamics and non-stationary parameters.  We have formulated and studied the  problem of finding the predictive estimation for the systems of differential equations with Gompertzian dynamics, for the case of continuous observation.  We have suggested the algorithms for building guaranteed predictive estimations for the model.  We have presented as an example, the results of numerical experiments to bu

ANALYSIS OF VERIFICATION AND CALIBRATION METHODOLOGIES OF MEASURING INSTRUMENTS

The article focuses on the main problems of metrological confirmation of measuring instruments in accordance with international requirements and considers possible directions of their solution. One of the main tasks of metrology is assurance of the uniformity of measurements, that is, the state of measurements, in which their results are expressed in the legal units, and the characteristics of errors or uncertainty of measurements are known with a certain probability and do not exceed  the established limits.