uncertainty

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 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.

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

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.

In  this paper  three examples of processing uncertainties of a  indirect multi-variable measurement system are considered. It was proposed to extend the vector method of estimating measurement uncertainties, given in Supplement 2 to GUM, on  the  statistical  description  of  the  accuracy  of  whole  ranges  of  indirect multivariable measurement  system.  Formula  for  the covariance matrix of relative uncertainties of the vector measurand is given.

When processing the results of measurements big role important presence of correlation values. To find the standard uncertainty need to know the effective number of uncorrelated observations. No correlation can consider could lead to incorrect evaluation of the standard uncertainty of the mean. Not always known autocorrelation function monitoring, and evaluation of the autocorrelation function on observations characterized by low accuracy, which can lead to incorrect finding effective number.

The essence of uncertainty serves as an attribute of political life. It is indicated that today the issue is related to various manifestations of political uncertainty in conditions of relative stability or instability and the crisis of transitional societies. The very nature of uncertainty is influenced by various aspects: uncertainty due to the fact that it is impossible to predict values of a factor with accuracy; transformation; unpredictable behavior of participants in a conflict of interests in politics.

The paper deals with the methods for defining the composition of the coal mixture burnt in boilers at combined heat and power plants. Indirect methods for defining the proportions of the two grades of coal in the mixture based on the available information on the quality characteristics of the coal are proposed. According to the first method the coal mixture composition is determined based on the values of volatile substances content in the combustible mass of the coal mixture and of each grade of coal making up the mixture.