The description of the National primary standard for the unit of average laser radiation power GET 28-2016 with a power range from 10^–9 to 5·10^–3 W is described. The principle of operation of a standard based on a photoelectric trap detector in the range from 10–9 to 5·10^–3 W is described. As a result of metrological studies at National primary standard, it was determined that the value of the total standard uncertainty of reproduction and transmission of an average power unit for the range from 10^–9 to 5·10^–3 W is no more than 0.36 %. The model and theoretical characteristics of the measuring beam splitter, allowing to expand the range of the National primary standard to the range of kilowatt power levels, are presented. National primary standard allows solving the problems of metrological support of promising low-level laser ranging systems both in the ground and in the aerospace fi eld, ensuring the uniformity of measurements of radiometric parameters of low-intensity laser radiation fluxes.

The current problem in the field of electrical measurements is considered in connection with the new defi nitions of SIunits of physical quantities adopted by the 26th General Conference on Weights and Measures in November 2018 (France, Versailles), namely, the reproduction of anohm based on the quantum Hall effect. The reasons for the introduction in 1988 of the Klitzing constant independent of the international system of units and its cancellation in 2018 are explained. The physical foundations of the quantum Hall effect are outlined. The main indirect and direct experiments that led to the creation of an ohm standard based on the quantum Hall effect, including those carried out at VNIIMS in 1982–1986, are analyzed. Using the example of these experiments, the identity of the values of the quantized resistance for samples prepared on the basis of inversion layers in silicon, gallium arsenide and in samples of a fundamentally new substance graphene is shown. Results on the use of graphene to create standards based on the quantum Hall   effect for various industries and science based on the latest advances in its production are presented.

A method for estimating the nonlinear functional of the probability density of a two-dimensional random variable is proposed. It is relevant when implementing procedures for fast bandwidths selection in the problem of optimization of kernel probability density estimates. The solution of this problem allows to signifi cantly improve the computational efficiency of nonparametric decision rules. The basis of the proposed approach is the analysis of the formula for the optimal bandwidth of the kernel probability density estimation. In this case, the bandwidth of kernel functions is represented as the product of an indeterminate parameter and the average square deviations of random variables. The main component of an undefined parameter is a nonlinear functional of the probability density. The considered functional is determined by the type of probability density and does not depend on the density parameters. For a family of two-dimensional lognormal laws of distribution of independent random variables, the approximation errors of the considered nonlinear functional from the probability density are determined. The possibility of applying the proposed methodology when evaluating nonlinear functionals of probability densities that differ from the lognormal distribution laws is investigated. An analysis is made of the effect of the resulting approximation errors on the root-mean-square criteria for restoring a non-parametric estimate of the probability density of a two-dimensional random variable.

The article is devoted to the automatic measurement of objects longitudinal dimensions on images obtained by probe microscopy. The solution of this problem can be relevant for quality control of microelectronics, nanotechnics products and materials. Existing tools for objects length measuring are compared by means of test image containing geometric figures with known dimensions. The advantages of software surface curvature detectors, intended for objects lengths measuring directly on a halftone image by forming the skeleton of an object with a surface curvature detector, are shown. A two-dimensional “Circle” detector, based on the curvature analysis of raster images line and column profilograms, was used for the measuring. The curvature was estimated based on the area of the figure bounded by the profilogram at a predefi ned interval. Features of measuring the length of objects using curvature maxima are considered. It is shown that the curvature detector allows to more accurately determine the lengths of objects with overlapping contours and a signifi cant brightness range. Algorithms of the detector operation, formation of the object skeleton and determination of its length are described. The results of investigation confi rming the performance of the presented algorithms are presented. Comparative analysis with existing length measurement tools, performed on magnetic disk domains and nanopolymer  fi bers images, showed a more correct detector operation in sceletonization of object and measuring its length.

The problem of developing control algorithms in quantum frequency standards based on the effect of coherent population trapping is considered. The development of such algorithms will make it possible to create frequency standards with metrological characteristics that are not inferior to the characteristics of rubidium frequency standards, with reduced power consumption and overall dimensions. A method for studying the dependence of the actual value and frequency instability of quantum frequency standards based on the effect of coherent population trapping on the operating modes of individual parts of the standards is presented. As a criterion for optimizing the laser injection current, the output power of the microwave generator, and the cell temperature, we chose to minimize the effect on the shift of the actual frequency of the standard. A comparative analysis of methods for changing the radiation intensity of a surface-emitting laser with a vertical resonator has been carried out and control algorithms have been developed that take into account the features of these methods. Based on these algorithms, software and tuning methods have been developed in quantum frequency standards based on the effect of coherent population trapping. For the prototype standard, the results of measuring the frequency instability are shown. It is shown that control algorithms and tuning methods can qualitatively change the metrological characteristics of quantum frequency standards based on the effect of coherent population trapping.

The problem of ensuring stability of Earth observation space-borne instruments undertaking long-term temperature measurements within thermal IR spectral range is described. For in-flight reliable control of the space-borne IR instruments characteristics the stability of onboard reference sources should be improved. The function of these high-stable sources will be executed by novel onboard blackbodies, incorporating the melt↔freeze phase transition phenomenon, currently being developed. As a part of these works the task of realizing an on-orbit calibration scale within the dynamic temperature range of Earth observation systems 210−350 K based on fixed-point phase transition temperatures of a number of potentially suitable substances is advanced. The corresponding series of the onboard reference blackbodies will be set up on the basis of the on-orbit calibration scale fixed points. It is shown that the achievement of the target lies in carrying out a number of in-flight experiments with the selected fixed points and the prospective onboard fixed-point blackbodies prototypes. The new In-Bi eutectic alloy melt temperature fixed point (~345 K) is proposed as the signifi cant fixed points of the future on-orbit calibration scale. The results of the new fixed point preliminary laboratory studies have been analyzed. The results allowed to start preparation of the in-flight experiments investigating the In-Bi alloy for the purpose of its application in the novel onboard reference sources.

The spatial characteristics of the erosion laser plasma are investigated. The application of small-sized spectrometers of the visible and ultraviolet ranges for recording the spectrum of plasma radiation is considered. Erosive laser plasma is formed on the surface of a silicon target under the action of pulsed laser radiation with a wavelength of 1064 nm under normal atmospheric conditions. The laser plasma torch was scanned using a movable slit diaphragm oriented parallel to the target surface. The emission of erosion laser plasma was recorded using small-size spectrometers. Based on the obtained plasma emission spectra, the dependences of the intensity of the spectral lines of silicon on the geometric position of the slit diaphragm are revealed. A comparison is made of the intensities of the spectral lines of silicon on the polished and grinded sides of the target.

The provision of technological processes with modern techniques for measuring temperature is a challenging issue. For solving this problem there need to be formulated specifi c requirements for the optical part of the pyrometer, intended for measuring the temperature in the measurement cavity of the installation used for calibrating tungsten-rhenium thermocouples up to a temperature of 2,200 °С. In accordance with these requirements, in mass produced “Termokont” pyrometer, its optical part has been modifi ed and experimentally investigated.

The article proposes a direct algorithm for reconstruction the electromagnetic field at the antenna aperture, which can be used to solve problems of diagnostics and spatial filtering. The algorithm is based on the solution of Maxwell's equations in the form of advanced potentials of the electromagnetic field. It is shown that following from it advanced electromagnetic waves are equivalent to retarded electromagnetic waves when the parameters of the medium are stationary and linear. The direct algorithm is formulated as the multiplication of the transformation operator matrix by the known vector of the electromagnetic field on a closed surface. In this case, the transformation outward (far field) or inward (aperture) of the surface is described by the same operator and differs only in the signs of the input quantities. Unlike the known ones, the direct algorithm does not require scanning the electromagnetic field on canonical surfaces or solving a large system of integral equations. This makes it optimal for use in new near-fi eld measurement systems based on industrial robots, unmanned aerial vehicles, etc. Verification of the developed algorithm using experimental data has shown the possibility of reconstruction the normalized distribution of the electric field strength at the antenna aperture with an error less than 2 dB.

Considered the issues of X-ray dose control during diagnostic and therapeutic procedures using imaging tools. The dose of X-ray radiation from the visualization devices absorbed by the biological tissue of a person was determined when monitoring the position of the patient on the therapeutic table of the electron accelerator before the radiation therapy session. The processes of transmission of photons and electrons through the medium were simulated, and the X-ray spectra were measured. The emission spectrum of the Varian G-242 Rotating Anode X-ray Tube was obtained using an XR-100-CdTe spectrometer. The absorbed dose is calculated by the Monte Carlo method. The absorbed dose in the water phantom at tube voltage up to 80 kV was 0,9–1,5 mGy.

The paper presents the results of studies on the development of metrological support for DNA sequencing. The sequencing of a standard sample of the human mitochondrial DNA was carried out according to the Sanger method on domestic capillary electrophoresis genetic analyzers Nanophore 05. The results of the work were used to validate standard reference material for human mitochondrial DNA sequence and to confi rm the DNA sequencer as a measurement instrument.

hydrogen index one of the most important methods for monitoring aqueous media. In 2013, work was carried out to enter into the State Register of Measuring Instruments of the Russian Federation a buffer solution and a standard titer with a pH value of 7.00 – a working pH standard of the 2nd category, which is one of the most demanded of non-standard solutions for verification and calibration pH measuring instruments. To confirm the metrological characteristics, pilot comparisons were organized within COOMET. This article presents the results of a pilot comparison to determine the pH of a phosphate buffer solution – a working standard of 8 metrological institutes and 10 metrological organizations took part in the comparisons. The results obtained showed that the overwhelming majority of the participants in the comparisons presented the results of pH measurements, which have an uncertainty not exceeding ±0.03 of the average value, which is an acceptable criterion for measuring the pH.