Measurement of time and frequency is one of the most widespread types of measurements, information on the exact value of time, on the national time scale is extremely in demand by a wide variety of consumers, ranging from commercial electricity metering systems, where the required synchronization accuracy is a few seconds, to space navigation systems that impose requirements on synchronization at the level of units of nanoseconds. At the same time, consumer requirements for the accuracy of time and frequency measurements, as well as for the efficiency of obtaining time-frequency information, are steadily growing, which entails the need to modernize the means of reproducing, storing and transmitting units of time, frequency and time scale. To meet modern consumer requirements for the accuracy of time and frequency measurements, technical means of reproduction, storage and transmission of units have been introduced into the State primary standard of units of time, frequency and national time scale GET 1-2022, allowing to significantly increase the contribution of GET 1-2022 to the formation of the coordinated universal timescale UTC. A brief overview of the composition of GET 1-2022 is given, a comparative analysis of the contribution of time standards to the formation of the UTC timescale is carried out, as well as an analysis of the shifts of the time scales of the standards relative to UTC and the instability of the frequency standards. It is shown that from September 2022 to March 2023, the contribution of GET 1-2022 to the formation of the UTC increased significantly and exceeded that of the US Naval Observatory standard, and currently the contributions of these standards are comparable. In terms of frequency instability and average contribution to the formation of UTC, the atomic standards of GET 1-2022 are significantly superior to similar standard instruments from other countries. It has been established that the national coordinated time scale UTC(SU) is one of the best national implementations of UTC, and the national atomic time scale TA(SU) occupies a leading position among the time scales of leading foreign time laboratories in terms of instability.

An alternative interpretation of the data is considered, on the basis of which in 1998–1999 a conclusion was made about the “acceleration of the expansion of the Universe”. The starting points of this interpretation were doubts about the legality of neglecting the effect of local emptiness, as well as a number of results obtained in solving measurement problems of cosmology. For this purpose, special programs “MMK-stat”, “MMK-stat M” and “MMI-verification” were used, designed to automate statistical data analysis in the tasks of verification and calibration of measuring instruments. The first two programs were used for the structural-parametric identification of the isotropic and anisotropic Friedman-Robertson-Walker models, respectively, in the form of a relationship between the photometric distance and the redshift of supernovae of type SN Ia in the class of power series. This dependence was analyzed as a mathematical model of the cosmological distance scale based on redshift. The gravitational dipole of inhomogeneity of the large-scale structure of the Universe is accepted as a physical mechanism for the mass accelerated motion of galaxy flows. A dipole of this kind consists of a pair of superclusters of galaxies and a giant void on opposite regions of the celestial sphere. The unbalance of the gravitational interaction in such a pair is perceived as an additional repulsive force of a comparable order with the influence of a supercluster. It is shown that there are at least five gravitational dipoles of this kind, which concentrate in the region of the galactic poles and form a giant Galactic polar gravitational dipole. It is shown that there are at least five gravitational dipoles of this kind, which concentrate in the region of the galactic poles and form a giant Galactic polar gravitational dipole, whose coincidence with the system of giant superclusters of galaxies in the Northern Galactic Hemisphere and the system of giant voids in the Southern galactic hemisphere is called “coincidence of coincidences”. This circumstance is considered as an alternative hypothesis to the hypothesis of “accelerating the expansion of the universe”. At the same time, it is not necessary to intro-duce exotic concepts of “dark matter” and “dark energy” to explain the observed facts.

The problem of testing the hypothesis about the independence of random variables in conditions of large volumes of statistical data is considered. The results of solving the problem are necessary when estimating probability densities of random variables and synthesizing information processing algorithms. A nonparametric technique is proposed for testing the hypothesis about the independence of random variables in a sample containing a large amount of statistical data. The technique is based on compression of the initial statistical information by decomposition of the range of values of random variables. The generated data array consists of the centers of sampling intervals and the corresponding frequencies of observations from the original sample. The information obtained is used in the construction of a nonparametric pattern recognition algorithm corresponding to the maximum likelihood criterion. The evaluation of the distribution laws in classes is carried out under the assumption of independence and dependence of the compared random variables. When restoring the laws of distribution of random variables in classes, regression estimates of probability densities are used. Under these conditions, estimates of the probabilities of pattern recognition errors in classes are calculated. According to their minimum value, a decision is made on the independence or dependence of random variables. The technique was applied in the analysis of remote sensing data of forest areas, linear and nonlinear dependencies between pairs of spectral characteristics of the objects of study were determined.

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The problem of the dynamic measurement error estimation and compensation is considered. This type of error is determined by two components. The first one is due to dynamic properties (inertia) of a sensor. The second one is due to the presence of an additive noise at the sensor output. An approach to estimate and reduce the dynamic measurement error based on the signals adaptive linear prediction or adaptive line enhancement principle is proposed. The approach consists in generating a dynamic measurement error estimation signal based on comparing a delayed copy of the recovered signal with the recovered signal passed through an adaptive non-recursive filter with a linear phase characteristic. The structure of a measuring system with an adaptive linear estimator of the dynamic measurement error based on this approach has been developed. A computer simulation of the proposed measuring system for the second-order sensor is carried out. Optimal (in the sense of the mean squared deviation of the dynamic error) orders of the restoring adaptive filter are obtained in the presence of additive harmonic noise of variable frequency at the sensor output. The properties of the proposed measuring system with the dynamic measurement error estimator adaptive to the noise parameter are demonstrated. The application field of the results obtained is the measurement data processing of fast-changing processes (including real-time mode), when the component of the dynamic measurement error, caused by dynamic properties (inertia) of the sensor, as well as additive noises at its output, is dominant. The solution of such a problem is relevant, for example, when processing the results of ground tests of space technology.

A new environmentally friendly fourth-generation refrigerant trans-1,3,3,3-tetrafluoropropene R1234ze(E) is considered as an alternative to R134a refrigerant in chillers and heat pumps, as well as R22 refrigerant in air conditioning systems. A technique has been developed for constructing a unified fundamental equation of state of liquid and gas, implemented for trans-1,3,3,3-tetrafluoropropene. The proposed fundamental equation in the vicinity of the critical point satisfies the requirements of the scale theory for asymmetric systems, and in the region of rarefied gas it is reduced to the virial equation of state. Based on this fundamental equation, tables of standard reference data on pressure, density, enthalpy, isobaric and isochoric heat capacities, entropy, heat of vaporization, and speed of sound, trans-1,3,3,3-tetrafluoropropene in the region of state parameters in the temperature ranges 169–420 K and pressure 0.1–100 MPa were calculated. A number of statistical characteristics have been calculated – absolute mean deviation, systematic deviation, standard deviation, root mean square deviation, which characterize the accuracy of the proposed fundamental equation in describing the experimental values of equilibrium properties obtained in generally recognized international thermophysical centers. It has been established that the values of these statistical characteristics are significantly less than the values of the corresponding characteristics of international fundamental equations given in the literature when describing thermal and caloric experimental data of trans-1,3,3,3-tetrafluoropropene. The estimated expanded uncertainties of the tabulated data obtained based on the proposed fundamental equation were 0.26 % for density, 0.57 % for pressure, 1.7 and 1.2 % for isochoric and isobaric heat capacities, 0.38 % for speed of sound. The results obtained allow us to conclude that the proposed unified fundamental equation of state adequately conveys the thermodynamic characteristics of trans-1,3,3,3-tetrafluoropropene in the specified range of temperatures and pressures.

The article discusses the control of technological parameters for the process of isothermal forging of cross-ribbed panels. To ensure defect-free manufacturing of panels, strict adherence to the temperature and rate conditions is required. However, due to errors and external disturbances, the measuring equipment does not often provide reliable information. In addition, the temperature of the metal in the deformation zone can only be estimated indirectly. Therefore, by analogy with the Kalman filter, it is proposed to combine data from sensors and the results calculated using the finite element method. For this purpose, the accuracy and speed of calculation of the finite element model were studied in four popular specialized software products: DeForm, QForm, Forge NxT, Simufact Forming. Comparison of the results of the analysis made it possible to confirm the high degree of reliability of modeling and the potential possibility of controlling technological parameters for the production of defect-free panels by the suggested way. It is shown that the finite element method in the two-dimensional formulation of the problem provides an acceptable calculation speed for monitoring the progress of operations in real time. The obtained results are relevant for metallurgical enterprises for which there are increased requirements for compliance with the range of permissible changes in technological parameters during production processes.

Rod downhole pumping units widely used in oil production are described. It is shown that oil production depends on the mode of operation of these units, which is selected based on the results of the analysis of closed dynamometer charts. Dynamograms describe the load on the suspension depending on the course of the polished rod of the installation, the quality of the construction of the dynamograms is decisive for diagnosing the technical condition of the installation. The trends in the development of existing dynamometer systems and methods for diagnosing the state of a sucker rod pumping unit are analyzed. One of the ways to create an intelligent intertraverse mesdoza dynamograph based on the mesdoza of a pocket dynamograph using modern pressure, acceleration, temperature sensors, STM32 controllers, a graphic liquid crystal display with an I2C interface, radio communication protocols and digital technologies for processing periodic sensor signals is presented. Based on the analysis of existing dynamometer systems and force and stroke sensors installed in various places of the installation design, and taking into account modern advances in technology and technologies for analyzing the noise of the measured signals, the possibility of developing an intelligent stationary dynamograph is shown. This dynamograph must provide early diagnostics of the technical condition of the installation and meet the following criteria: low cost; ease of installation; high sensitivity, reliability, flexibility and accuracy. A block diagram of an intelligent intertraverse dynamograph of the mesdoza of a sucker-rod deep pumping unit, based on the mesdoza of a pocket dynamograph, is presented. The proposed intelligent intertraverse dynamograph will be useful for early diagnostics of the technical condition of downhole pumps and tubing pipes connecting them with ground equipment, which will ultimately help to improve the reliability of oil production equipment. The proposed intelligent intertraverse dynamograph can also be used in other areas of technology where there is a need to measure force.

Various interferometers used for high-precision spectroscopic measurements are considered, and the choice of a holographic interferometer based on the spatial-spectral method of holographic interferometry is justified, with the help of which the movements of the phase center of a coherent light flux in a wide dynamic range are measured in real time and measurement information is recorded digitally. On the basis of mathematical relations proposed by the authors in previous publications and based on the results of experimental studies, the sensitivity of a holographic interferometer to spatial displacements of phase centers (focus points) of light streams – point light sources forming a holographic interferogram is numerically estimated. The dependence of the level of the normalized intensity of the luminous flux in the central region of the holographic interferogram on the movement of the actual point light source along the normal to the plane of the Fourier hologram is established. Based on the results of mathematical modeling, it is shown that the sensitivity of the holographic interferometer to the movements of a real point light source along the normal to the plane of the Fourier hologram depends on the parameters of the optical scheme of the holographic interferometer when exposing the hologram and during measurements. At the same time, the sensitivity of the holographic interferometer to the indicated displacements of a real point light source can only be evaluated experimentally. It is proposed to increase the sensitivity of the holographic interferometer by using a thin collecting lens in its optical scheme. For the first time, a mathematical relation was obtained and investigated for the gain coefficient of the light flux phase with a spherical wavefront, which makes it possible to numerically estimate the increase in sensitivity of a holographic interferometer implementing the spatial-spectral method of holographic interferometry with known parameters of a thin collecting lens in an optical scheme. It is shown that the sensitivity of a holographic interferometer to the movements of an imaginary point light source along the normal to the plane of the Fourier hologram is 2.86 times greater than its sensitivity to the same movements of a real point light source. It is established that the sensitivity of a holographic interferometer with a volumetric Fourier hologram and a thin collecting lens in its design can be increased by at least an order of magnitude compared to the sensitivity of known optical interferometers. The results of assessing the sensitivity of a holographic interferometer implementing the spatial-spectral method of holographic interferometry to the movements of point sources of real and imaginary light fluxes, as well as the obtained ratio for the gain of the light flux phase gain by a thin collecting lens will be useful for high-precision measurements of linear and angular displacements of objects, as well as for the construction of photonic device designs. Based on the results of the study, an experimental sample of an acousto-electric converter was developed and manufactured on the basis of a holographic interferometer, which has high sensitivity in wide dynamic and frequency ranges and is intended for use in acoustic location of unmanned aerial vehicles.

This research relates to the field of speech technologies, where the key problem is the optimization of speech signal processing under conditions of a priori uncertainty of its fine structure. The task of automatic (objective) analysis of voice timbre using a speech signal of finite duration is considered. It is proposed to use a universal information-theoretic approach to solve it. Based on the Kullback-Leibler divergence, an expression is obtained for the asymptotically optimal decision statistic for distinguishing speech signals by voice timbre. Pointed to an acute problem in its practical implementation, namely: synchronization of the sequence of observations with the main tone of speech signals. To overcome the described problem, an objective measure of timbre differences in speech signals is proposed in terms of the acoustic theory of speech production and its model of the speaker’s vocal tract of the “acoustic trumpet” type. The possibilities of practical implementation of a new measure based on an adaptive recursive are considered. A full-scale experiment was set up and carried out. According to its results, two main properties of the proposed measure were confirmed: high sensitivity to differences in speech signals in terms of voice timbre and, at the same time, invariance with respect to the pitch frequency. The results obtained can be used in the design and research of digital speech processing systems tuned to the speaker’s voice, for example, digital speech transmission systems, biometric, biomedical systems, etc.

The most informative, direct and non-invasive method for studying the basic protective mechanisms of the respiratory organs, the processes of deposition of inhaled substances and the clearance of them from the lungs is radioaerosol. It involves the inhalation of a diagnostic drug labeled with a radioisotope or a radioactive drug, based on the dynamics of distribution and excretion of which the indicated processes are judged. These processes and the accuracy of their assessment depend on the aerodynamic properties of the inhalant. In order to optimize the measurement of the parameters of the aerodynamic properties of a diagnostic aerosol and the function of the main protective mechanisms of the respiratory organs, a comparative analysis of different measurement methods and dispersion systems of albumin, chosen by us as the most physiological material, was performed. It has been established that the most informative and economically feasible method for assessing the aerodynamic properties of an inhalant is scanning electron microscopy. A comparative assessment of albumin macroaggregates produced by foreign representatives and albumin microspheres produced using the technology of domestic researchers, carried out using scanning electron microscopy, indicates that domestic albumin microspheres have optimal aerodynamic parameters for studying lung deposition and clearance. However, to make a final judgment about the possibilities of using these albumin microspheres, a direct assessment of their deposition in the lungs is necessary.