Informational uncertainty of measuring instruments

Recently, there has been a revival of interest in the use of the information approach in the theory of measurements. Unlike the traditional approach, information theory does not evaluate error or uncertainty, but entropy and the amount of information. This article analyzes a number of recent publications that develop ideas for the information approach. The limitations and disadvantages of both the entropy approach and the concept of uncertainty are indicated. As a compromise solution, it is proposed to use a criterion based on the Bongard’s uncertainty and useful information. The concept of information uncertainty is proposed, which is estimated by the amount of negative useful information, that is, misinformation introduced by the measuring instrument. Some methods for calculating information uncertainty are described. The problems of using the uncertainty approach are noted. This approach does not imply the use of such a generalized characteristic of measuring instruments as an accuracy class. The article proposes an analogue of the accuracy class in the form of relative informational uncertainty, expressed as a percentage. This will make it possible to evaluate the quality of the measuring instrument by a single parameter, the calculation of which requires a minimum of computational operations.

GEODESY, CARTOGRAPHY AND AERIAL PHOTOGRAPHY

The aim of the research is to diagnose the metrological characteristics of high-precision GNSS-observations by methods of non-classical error theory of measurements (NETM) based on Ukrainian reference stations. Methodology. We selected 72 GNSS reference stations, downloaded daily observation files from the LPI analysis center server, and created time series in the topocentric coordinate system. The duration of the time series is almost two years (March 24, 2019 - January 2, 2021). Using a specialized software package, the time series have been cleaned of offsets and breaks, seasonal effects, and the trend component has been removed. Verification of empirical distributions of errors was provided by the procedure of NETM on the recommendations offered by G. Jeffries and on the principles of hypothesis tests the theory according to Pearson's criterion. The main result of the research. It is established that the obtained time series of coordinates of reference GNSS stations do not confirm the hypothesis of their conformity to the normal Gaussian distribution law. NETM diagnostics of the accuracy of high-precision GNSS measurements, which is based on the use of confidence intervals for assessing the asymmetry and kurtosis of a significant sample, followed by the Pearson test, confirms the presence of weak, not removed from GNSS-processing, sources of systematic errors. Scientific novelty. The authors use the possibility of NETM to improve the processing of high-precision GNSS measurements and the need to take into account the sources of systematic errors. Failure to take into account certain factors creates the effect of shifting the time coordinate series, which, in turn, leads to subjective estimates of station velocity, i.e. their geodynamic interpretation. Practical significance. Research of the reasons for deviations of errors distribution from the established norms provides metrological literacy of carrying out high-precision GNSS measurements of large samples.

Applying Measurement Theory and Information-based Measure in Modeling Physical Phenomena and Technological Processes

In this paper, we compare the features of the application of the theory of measurements and the measure of the similarity of the model to the phenomenon under study on the basis of calculating the amount of information contained in the model. An experimental estimate compared with the standard model’s uncertainty calculation procedure shows that this measure is preferable to the traditional approach to calculating the threshold discrepancy. The article presents an algorithm that is used to calculate the minimum achievable uncertainty in the resolution of the model's fuzziness, as well as experimental results demonstrating its effectiveness.