The possibility of circumventing the problem of decomposition of the range of values of random variables when testing various hypotheses is considered. A brief review of the literature on this problem is given. A method for forming sets of independent components of a multidimensional random variable is proposed, based on hypotheses testing about the independence of paired combinations of components of a multidimensional random variable. The method uses a two-dimensional non-parametric algorithm for pattern recognition of the kernel type, corresponding to the criterion of maximum likelihood. In contrast to the traditional method based on the application of the Pearson criterion, the proposed approach avoids the problem of decomposing the range of values of random variables into multidimensional intervals. The results of computational experiments performed according to the method of forming sets of independent random variables are presented. Using the information obtained, an information graph is constructed, the vertices of which correspond to the components of a multidimensional random variable, and the edges determine their independence. Then the vertices of the complete subgraphs correspond to groups of independent components of a random variable. The obtained results form the basis for the synthesis of a multi-level nonparametric large volume data processing system, each level of which corresponds to a specific set of independent random variables.

Assessment of the state of the system of ensuring the uniformity of measurements is an urgent task, the solution of which is necessary for monitoring and forecasting its state. The paper proposes an approach to the development of a methodology for monitoring the state of the system to ensure the uniformity of measurements and forecasting its state, which takes into account the mutual influence of subsystems on each other. The approach is based on the hierarchy analysis method. The decomposition of the system of ensuring the uniformity of measurements for further processing of the sequence of judgments of the person (group of persons) making the decision is considered. The judgments are based on paired comparisons of the decomposition elements. The method of processing the judgments of a group of experts in order to obtain a generalized judgment on paired comparisons is described. The obtained results can be used as part of monitoring the state of the system for ensuring the uniformity of measurements and forecasting the measurement needs of the economy and society.

Different consumers of global navigation satellite systems signals are able to receive different combinations of them. For this reason, it is important to monitor the signal parameters separately. The existing partial signals characteristics measuring methods are based on correlation processing, which leads to the loss of measurement information and signal averaging. A method for measuring the partial powers of navigation signals with frequency and code division was developed. The initial data are the total spectral power density measurements results, as well as information on the shape of the partial spectral power densities. A mathematical model of the sum of signals with overlapping spectra was investigated. It was shown that the signal powers were related as coefficients at partial spectral power densities. A system of equations for the coefficients is compiled, its solution is presented by the Tikhonov method. A practical study of the metrological characteristics of the method has been carried out. The research results will be used during monitoring the navigation spacecraft technical condition.

The problem of size droplet determining by the Interferometric Particle Imaging (IPI) in a spray of an optically transparent liquid is considered. The measurements were carried out using the example of a fuel injector flame. A new method for analyzing the IPI image of a droplet using a continuous wavelet transform is proposed. The spatial distribution of wavelet coefficients is used to introduce an integral measure similar to the spectral density of the signal. As a reliable estimate of the droplet size, we considered the results by the Glare Point Technique (GPT), which were applied simultaneously. A comparative analysis of the sizes obtained using GPT and IPI showed that the application of the wavelet transform to IPI images, in comparison with the Fourier method, significantly reduces the frequency of occurrence of a systematic error in determining the size, which is most specific for large droplets. It was found that the false maxima in the Fourier spectrum causing these errors are due to the appearance of distortions at the boundary of the interferometric image of the droplet. The wavelet transform allows one to separate these distortions from the main maximum in the vicinity of the droplet center.

The problem of increasing the accuracy of recording the pulse shape of a rapidly changing current of a powerful plasma emitter under conditions of powerful electromagnetic interference is considered. To register high-current pulsed discharges, it is proposed to use a polarimetric fiber-optic current sensor based on a Spun-type fiber. Using the indicated current sensor, a technique for recording high-current pulsed discharges of a plasma emitter in the mode of time profiling of the current pulse of two high-voltage capacitive storage devices with a total energy of up to 1800 kJ is realized. The discharge chamber, power supply circuits, and the formation of a plasma discharge are described. The design and principle of operation of a prototype of a two-pass polarimetric fi beroptic sensor with a Spun-type fiber and a Faraday compensator of mutual optical anisotropy are presented. The general scheme of current measurements, the sensor calibration scheme is presented, and the experience of using a prototype sensor for measuring high-power pulse currents is described. The features of the preliminary calibration of the sensor are discussed. The results of measuring the current by optical and traditional recording methods based on the Rogowski coil and Hall sensors are compared with each other, and a noticeable increase in the accuracy of reproducing the current pulse shape by the optical recording method is noted. Possible options for upgrading a fiber-optic sensor to expand the range of current recording are considered.

The actual problem of the possibility of using the equations of state for the gas phase of natural gas at temperatures below 250 K is considered. To solve it, the compressibility coefficients of natural gas obtained experimentally with high accuracy are required. The technique was developed and experimental study was carried out of compressibility factor aiming expanding temperature range of the state equations GERG-2004 and AGA8-DC92. The proposed technique is based on the fact that to assess the applicability of the equation of state, it is sufficient to obtain the relative value of the compressibility coefficient and not to determine its absolute value. The technique does not require complex equipment and provides high accuracy. The technique was tested on nitrogen, argon, air and methane. Uncertainty of determination of the compressibility factor is not greater than 0.1 %. For two different compositions of natural gas, obtained experimental data were demonstrated that the equations of state GERG-2004 and AGA8-92DC provide uncertainty of the calculation of the compressibility coefficient within 0.1 % in the temperature range from 220 K to 250 K and pressure below 5 Mpa.

The electrical characteristics of superconducting coils with non-insulated windings are studied. The procedures for measuring the parameters of uninsulated superconducting windings are described. In particular, the inductance is measured by voltage with a linear current input at a given rate. Attention is focused on the impossibility of correctly determining the inductance in a winding with an uninsulated superconductor in a normal state. It is noted that in a superconducting state at currents below the critical value, the inductance of the winding is comparable to the inductance with an insulated wire. The results of measurements of inductance, radial resistance, static current-voltage and magnetic characteristics of two tape coils with non-insulated superconducting windings, one of which had a soldered connection, are presented. Conditions for measuring the parameters of non-insulated superconducting windings are formulated when they are compared with insulated windings.

The necessity of improving the State primary special standard for a unit of pulsed electric voltage GET 182-2010 is substantiated on the basis of an electro-optical sampling system. Approaches to ensure the uniformity of pulse measurements are proposed, aimed at developing a new system of measurements traceability of pulsed signals parameters to the units of the International System of Units, as well as ensuring independent reproduction of reference ultra-wideband electrical pulses. The considered approaches can be used to work on GET 182-2010 improvement. The main tasks of further research in the direction of creating a domestic electro-optical sampling system are formulated.

The issues of experimental determination of electrodynamic parameters of existing and new synthesized materials and coatings used in the microwave range are highlighted. Problems arising from measurements of the electrophysical and geometric parameters of dielectric and magnetodielectric coatings, taking into account their placement on a metal substrate, by radio wave methods are considered. We present the new radio wave method of joint measurements of the frequency dependence of the complex permittivity, the frequency dependence of the complex magnetic permeability, and the thickness of plane-layered samples of dielectric and magnetodielectric coatings on a metal substrate. Determination of electrophysical and geometric parameters of the coating in the proposed method is reduced to minimizing the objective function constructed based on the discrepancy between the experimental and design theoretical values of the attenuation coefficients of surface electromagnetic wave fields on a grid of discrete frequencies. The simulation model of measurements is shown, implemented on the basis of the electrodynamic modeling system CST Microwave studio (Simulia corporation, USA) and the Matlab system. The results of simulation are presented to determine the frequency dependences of the electrophysical parameters and the thickness of a sample of a radio-absorbing coating on a metal substrate. Errors in the estimates of permittivity and permeability in the measurement frequency band 9–13.5 GHz, which are no more than 10 % with a confidence level of 0.95 with a mean square deviation of the noise level of 0.006, have been obtained. The proposed method can be in demand in various science-intensive areas – microelectronic, aerospace, mechanical engineering, etc.

The problem of skin melanoma diagnostics from digital images of the tumor is considered. Clinical algorithms for detecting skin melanoma are briefly described. An overview of the works devoted to the automated assessment of the asymmetry of the distribution of shape, color, area of globules – important signs of melanoma – is given. A model for estimating the heterogeneity of the distribution of the characteristics of globules on digital images in the skin neoplasms diagnosis is developed and models of signs of heterogeneity of this distribution are proposed. The comparative evaluation of the proposed models was carried out experimentally using a software system developed in C++. The most informative features are identified. The greatest accuracy 93 % in estimating the heterogeneity of the distribution of the characteristics of globules was shown by the sign “the reduced inverse of the greatest frequency of occurrence of the measured areas of globules”. The results obtained can be applied in the development of systems to support medical decision-making in the diagnosis of melanoma.

The results of additional comparisons of the national standards of the unit of the harmonic coefficient of Russia (VNIIFTRI) and the Republic of Belarus (BelGIM) are presented. A mass-produced harmonic coefficient meter was used as a reference carrier. The differences between the harmonic coefficient unit reproduced by national standards the reference values do not exceed the extended uncertainty for all measured values of the harmonic coefficient and at all frequencies. Thus, the measurement and calibration capabilities of the laboratories participating in the comparisons are confirmed.