The article provides a description of specifi cations of the State primary standard of the frequency deviation, methods and means for measurement frequency deviation, which used at standard. A direct digital signal synthesis method has been implemented to reproduce the frequency deviation unit. This method is devoid of a number of sources of errors in measuring frequency deviation and allows you to signifi cantly expand the ranges of carrier and modulating frequencies, as well as increase the maximum reproducible value of the frequency deviation unit by 10 times without increasing the non-excluded systematic error. The primary standard includes modern measuring instruments based on digital signal analysis - a signal analyzer and a digital storage oscilloscope, which allow transmitting a unit of frequency deviation to reference measuring instruments and signifi cantly expand the capabilities of the primary standard. Are given experimental investigations results of improved standard. The scope of application of the State Primary Standard of the Frequency Deviation Unit GET 166-2020 is considered, covering modulation meters, signal generators, measuring receivers, spectrum/signal analyzers, phase jitter meters, phase noise analyzers, generators and analyzers of digital modulation types. Experimental results of studies of GET 166-2020 are presented. The partial components of the measurement errors of the four independent measurement methods used are estimated, some of the components of the errors are excluded or reduced many times. Comparison of the measurement results by each of the methods used indicates the convergence of the measurement results of the frequency deviation unit within ±(0.02...0.05) %.

The composition and characteristics of the State primary standard of the unit of electric field strength in the frequency range, of 0–20 kHz GET 158-2020 are described. The lower limit of the frequency range for reproducing an alternating electric field, in accordance with regulatory requirements, has been expanded from 20 Hz to 5 Hz; the upper limit of the range for reproducing the electric field strength has been expanded to 4000 V/m. The NSP of the standard is 1.4 %, the zero value of the electric potential in the center of field-forming system is provided. The peculiarities of estimation of the components of the non-excluded systematic error and the error of transferring the unit of electric field strength, related to the symmetric configuration of the standard, are discussed, including those due to the interaction of measuring antennas with the electrodes of field-forming system. A draft of the State verification scheme for electric field strength measuring instruments was developed and discussed, taking into account all the trends in the development of this type of measurement.

Two formats for the representation of uncertainties in solving measurement problems are considered: the probability distribution and the scattering parameter of the distribution. Inconsistency of definitions of a number of terms GOST R ISO 3534-1-2019 “Statistical methods. Dictionary and symbols. Part 1. General statistical terms and terms used in probability theory” and the lack of definitions of important terms – composition, convolution, probability of agreement, mixture of distributions. It is shown that the convolution of probability distributions gives the most complete representation of the probabilistic properties of the uncertainty of results in metrology.

A multi-step algorithm based on the Bayesian approach to constructing effective statistical estimates of measurement results has been developed. A general logical scheme of a multi-step algorithm is presented, which allows, in the case of heterogeneity of a priori and a posteriori data, to build generalized Bayesian estimates based on the use of a mixture of a priori and a posteriori distributions. Conditions for the existence of a conjugate family of a priori distributions are formulated. A technique for calculating specific values of parameters in conjugate a priori distributions is described. The technology for applying the Bayesian approach is described in more detail for the binomial and negative-binomial distribution laws. Using the likelihood function, formulas for recalculating the parameters of the corresponding conjugate distribution law are obtained, which allow one to pass from the next step to the next step of the multi-step algorithm. Examples of applying the algorithm to the problem of assessing the compliance of measuring systems with specified requirements, as well as to the problem of processing the results of quantitative physical and chemical analysis are given. The presented results show that the Bayesian approach gives a significant gain in the accuracy of constructing statistical estimates for small and medium sample sizes. This circumstance makes the Bayesian approach particularly effective in the problems of assessing the metrological characteristics of measuring systems in the case when repeated repetition of tests is inexpedient or time consuming. On specific examples, it is illustrated that with an increase in the volume and number of samples, the multi-step Bayesian approach and the classical maximum likelihood method will give identical results.

The fundamentals of identification of spatial distributions of laser beam intensity are presented. This identification is essential for the certification of laser sources. The task of identification is to assess the similarity of the distribution of the intensity of the radiated field with a given (calculated) distribution. A methodology for identifying spatial distributions of laser beam intensity is proposed. To form measures of similarity of the intensity distribution of the radiated field with an arbitrarily given distribution, a mathematical apparatus based on functional inequalities has been developed. Various measures of similarity are considered, a number of spatial intensity distributions are compared with Gaussian and uniform intensity distributions depending on the dynamic range of the identification tool. The sensitivity of similarity measures to the shape of the intensity distribution of the emitted field is shown. It is proved that such well-known characteristics as the aberration factor and the propagation coefficient of the laser beam are special cases of measures based on solutions of functional inequalities.

The article discusses a method for modeling the differential pressure flowmeters of using machine learning methods. In the proposed work, a model in the form of a support vector machine is used as the discharge coefficient of the orifice plate. The paper describes in detail the learning process of the proposed model, and discusses its structure for the discharge coefficient in the form of a support vector machine, provides training parameters. The paper also provides simulation results, both during training and during testing of the model, which confirm the effectiveness of the proposed alternative method of reproducing the discharge coefficient. The authors of the article presented a comparative analysis of the obtained model for the discharge coefficient in the form of a support vector machine with the values of the current Reader-Harris and Gallagher equation. The paper shows that the model of the discharge coefficient in the form of a support vector machine is not inferior in accuracy and efficiency to the current models, and allows improving the systems for measuring the flow rate of liquids and gases. The obtained research results for differential pressure flow measurement systems of gas are relevant, and are of interest for natural gas production, transportation and storage facilities.

The current research of high-impedance conformal surfaces on metamaterials and multifunctional measuring devices based on them makes the task of determining their parameters and characteristics urgent. In this article, a geometric method for determining the phase shift in the in-phase refl ection of an electromagnetic wave from the conformal meta-surface of a sensitive element is developed and proposed. It is shown, that as a result, of the meta-surface bending the incident electromagnetic wave passes an additional path at a certain electrical length, which leads to an increase in the phase shift of the refl ected wave. Using the CST Studio Suite numerical simulation program, the values of the phase shift of incident and refl ected waves for planar and curved metasurfaces of sensitive elements of various topologies with radii of curvature of 40; 50; 60 mm are obtained. The results obtained were compared with analytical calculations, which showed a good correspondence. The proposed method can be used to calculate and simulate measuring transducers containing sensitive elements on high-impedance conformal meta-surfaces.

The necessity of increasing the accuracy of measuring the flow rate of the coolant in the first loop of a nuclear reactor for mobile objects has been substantiated. The necessity of monitoring the state of the coolant in the current flow in the pipeline is additionally substantiated. At the moment, in nuclear power plants of mobile objects, the control of the state of the coolant in real time is not implemented. Problems arising when controlling the flow rate of the coolant by various models of flow meters in the primary circuit of a nuclear reactor are considered. It was found that the use of nuclear magnetic flow meters allows them to be solved. A new design of a tagged-type nuclear magnetic flowmeter-relaxometer has been developed using modulation techniques and modulation of the magnetic field in the area of the nutation coil to register the nuclear magnetic resonance signal. Methods for measuring the times of longitudinal and transverse relaxation of the current coolant are proposed. The paper presents the results of studying the parameters (flow rate and relaxation times) of the model solution flowing in the pipeline, which contains the chemical elements that make up the coolant for nuclear reactors of mobile objects. It was found that the measurement error for these parameters does not exceed 1 %. The prospects of using the developed design of a nuclear-magnetic flowmeter-relaxometer in the first circuit of a nuclear reactor of a mobile object are shown.

The problem of reducing measurement errors of radar stations is investigated. The problem of increasing the accuracy of radar measurements of range and elevation by compensating for systematic errors with the construction of their mathematical models in the form of polynomial equations of the second and third degree for the case of rectilinear motion of the aircraft is solved. Based on the analysis of the solutions of these equations using mathematical modeling, algorithms for compensating for systematic errors in radar measurements of range and elevation are synthesized. Recommendations and restrictions on the use of the proposed algorithms, which will be useful in the calibration of radar stations, are presented.

The technical aspects of the construction of devices for measuring the moisture content of grain and products of the agroindustrial complex have been studied. The necessity of developing primary moisture measuring transducers has been substantiated. The dielcometric method for determining humidity, based on the dependence of the dielectric constant of the controlled material on its humidity, is considered. The dependencies linking the electrophysical parameters of materials with humidity and uninformative parameters of materials are studied. A structural diagram of a high-frequency moisture meter is presented, the principle of operation of which is based on the dielcometric method of measuring the moisture content of materials. A prototype of a grain moisture control device has been developed with an electrical model of the primary measuring transducer. The proposed high-frequency moisture meter can be used to measure the moisture content of grain and grain products in industrial and laboratory conditions.