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The article presents the concept of a promising hardware and software complex based on an unmanned aerial vehicle equipped with an on-board system for automatic detection of ground objects and route correction. The key features of the hardware and software complex will be such features as: - performing data processing on board the unmanned aerial vehicle; - possibility of autonomous route adjustment. The study was carried out under the Agreement 615GRNTIS5/63369 dated 03.12.2020 Fund for the Promotion of Innovation

The article considers the creation of a dataset for further training a neural network to identify people from an unmanned aerial vehicle (UAV) in two ways. With the first marking method, only people are marked on the images. With the second marking method, all objects that are present on the frame are marked. Techniques for creating two datasets are given, the classes into which the objects in the images were divided are described. Using the two datasets obtained, the Yolov4 neural network was trained. The article presents the result of the work of two neural networks, shows a comparison of their accuracy and completeness. This project shows whether the accuracy of a neural network will increase if it is taught not only to find objects of interest, but also to distinguish them from other objects. The publication shows the errors that were recorded in the work of two neural networks and their justification.

It is ascertained that heating of volcanic material from the Etna volcano (Italy) by an apokampic discharge reduces the voltage at which a positive streamer (apokamp) starts from the discharge channel and increases its propagation speed. The luminescence spectra show these processes to be accompanied by the emission of easily ionizable K and Na, which is consistent with data on the elemental composition of Etna samples. A hypothesis is suggested about an increase in the appearance probability of blue jets and starters over sites of high volcanic activity at altitudes of 10–18 km (at the level of the troposphere).

It is shown that the channel of apokampic discharge is a source of streamers at low air pressure and low frequencies (7–16 Hz) of high-voltage positive-polarity pulses and voltage amplitudes from 26 to 35 kV. The maximal starting speed of laboratory streamers was 560 km/s. A hypothesis about blue jet origination in nature is suggested based on experimental data. For their start, high frequencies of voltage pulses are not required, breakdowns in the Hz range are sufficient, but the discharge channel should bend and the field intensity should be high at the bending point.

The experimental and theoretical investigations of a new form of burning of a repetitively-pulsed discharge – apokamp – are performed. It is shown that an apokampic discharge represents a narrow streamer channel, growing from the point of plasma channel bending, having a characteristic propagation velocity of tens and hundreds of meters per second, depending on the applied voltage and gas pressure and type. The conditions necessary for an apokamp to evolve are formed in a comparatively weak macroscopic electric field. The channel bend ensures a local field enhancement, which prescribes the starting orientation of the growing streamer channel. The pulse-frequency power supply regime of the discharge reproduces the streamer channel in every pulse, but the preceding framework of the ion-ion plasma ensures reproduction of the channel shape from pulse to pulse.

It is observed that the formation of an apokamp is preceded by the appearance of streamer coronas starting from the channel of a repetitively pulsed discharge. It is shown that the streamer coronas under experimental conditions alleviate the development of an apokamp, acting as a preionization source.

A corona discharge is experimentally studied in atmospheric air on a needle electrode with the curvature radius 40 μm. For both electrode voltage polarities, but different discharge burning modes, repetitive current pulses with the FWHM ~200 ns are registered. It is shown that in a wide range of negative-polarity voltages the area of the glow registered in the vicinity of the needle has a spherical shape, and in the case of a positive polarity of the needle tip, starting from a certain voltage value, cylindrical streamers are formed from the spherical glow area, whose length increases with the voltage. It is found out that the size of the glowing spherical formations near the needle tip, given the same voltage value, is larger in the case of negative polarity than in the positive one. It is validated that the radiation of the second positive system of nitrogen in the UVspectral region dominates in the corona discharge emission spectrum before its transition into a spark discharge.

Laboratory simulation of the conditions for the occurrence of blue jets in the Earth’s atmosphere has been carried out. For this purpose, the diffuse formation of jets and plasma buildup in corona and apokampic discharges in air has been studied. It is shown that the jets are formed due to streamer breakdown and their color depends on air pressure. At atmospheric air pressures of 30–120 Torr, streamers starting from different parts of a repetitively pulsed discharge are recorded in a nonuniform electric field. It has been ascertained that a spherical corona discharge is formed before a breakdown between pointed electrodes, near a metal high-voltage electrode of positive polarity, from which streamer coronas start as the voltage increases. Data on the streamer head size and streamer propagation speed in the corona and apokampic discharges are presented.

Heat capacities of aqueous solutions of anionic surfactant sodium decyl sulfate in the 0.28–0.42 mol kg−1 range of molar concentrations and the 278–363 K range of temperatures are studied via precision adiabatic differential scanning microcalorimetry. Specific and apparent heat capacities of solutions at intervals of 0.01 mol kg−1, partial molar heat capacities of the solute and the solvent, and excess partial molar heat capacities are plotted as functions of concentration and temperature. The Kraft boundary is determined. Analysis of the characteristic changes in the above properties reveals structural changes in sodium decyl sulfate micelles that correspond to their shape transforming from cylindrical to plate-like in the region of the third critical micelle concentration.

BACKGROUND The liver’s function is impaired above all others in the mechanical jaundice, which leads to the progression of endogenous intoxication and the damage of different organs and systems, including the brain. The development of hepatic encephalopathy undoubtedly aggravates the course of the disease, which requires its timely management.AIM OF STuDy: to evaluate the effcacy of the low-intensity laser therapy when managing the cerebral dysfunction in mechanical jaundice of non-tumor origin.MATERIAL AND METHODS A comprehensive study of 60 patients with obstructive jaundice of non-tumor origin was performed. The patients were divided into 2 groups: I (comparison) — the standard therapy (n=30); II (studied) group — inclusion of low-intensity laser irradiation of blood (n=30). On check dates (day 1 and 7), the severity of cerebral dysfunction was assessed in all patients using the psychometric tests (“Point in Circle, “Labyrinth”). The microcirculation was assessed with LACC 02 device (Russia). The coagulation/lysis system of blood was studied with TEG 5000 thrombelastograph (USA).RESULTS In patients with obstructive jaundice, disorders of the functional state of the liver were noted, which resulted in the growth of total bilirubin, alanine and aspartic aminotransferases, and toxic products. All this was accompanied by cerebral dysfunction, which was shown by results of the psychometric study and extended performance of tests, in particular (“Point in Circle”, “Labyrinth”). Signifcant changes and disorders of the hemostatic system were revealed in patients. The complex treatment of obstructive jaundice, which included laser therapy, allowed a relatively rapid recovery of the functional state of the brain to be observed, as evidenced by the shortening of the test time for the tests being studied. The positive effect of this kind of therapy was accompanied by a decrease in the severity of the syndrome of endogenous intoxication, improved microcirculation and hemostasis.CONCLUSION The presence of pancreatic obstructive jaundice lead to the development of florid syndrome of endogenous intoxication, which was reflected in the growth of ALT, AST, amylase, and total bilirubin. During the entire period of the study, a decrease in studied blood parameters was observed in patients who had underwent low-intensity laser therapy sessions. Conducting a psychometric study in the initial periods revealed some violations, such as extended performance of tests (“Point in Circle”, “Labyrinth”).

A system of two-phase signals with spread in space and summation into a radio channel according to the SIMO 2x1 scheme was designed. With correlated reception of the mixed (combined) signal, the system provides modulation efficiency of 17 bits/sample. The main problem (challenge) at receiving is resolving of ambiguity of the optimal value of the initial phase in the mixed (combined) signal, that defines the maximum modulus of the cross-correlation function of the signal. It is necessary to clarify the signs of the trigonometric functions of angles, which makes it possible to determine the true values of initial phases of the signals transmitted.

A system of two-phase signals with spread in space and summation into a radio channel according to the SIMO 2×1 scheme was designed. With correlated reception of the mixed (combined) signal, the system provides modulation efficiency of 17 bits/sample. The main problem (challenge) at receiving is resolving of ambiguity in determining the optimal value of the initial phase in the mixed (combined) signal, that defines the maximum modulus of the cross-correlation function of the signal. It is necessary to clarify the signs of the trigonometric functions of angles, which makes it possible to determine the true values of initial phases of the signals transmitted.

A new approach to optimization of linear reinforced concrete elements of variable height without prestressing reinforcement is proposed. It is based on the design situation, which is determined by the strength requirements of normal and inclined sections. At the same time, the design and design requirements for sections of various heights are fully met without the need to set the design compressed reinforcement. The study was carried out on the basis of taking into account the regularities of the resistance of reinforced concrete and the main provisions of the regulatory documents governing design and construction activities in the Russian Federation. Also used are the actual works of domestic and foreign scientists, corresponding to the research in this area. During the study, the results of strength calculations of normal and inclined sections were used, as well as the cost indicators of materials used for the manufacture of structures. The method of structural and analytical analysis was used using the correlation dependences of the factors under study. Analytical dependencies and graphic materials are presented that establish the optimal parameters of an element with a minimum cost of materials in order to use them in design practice. The proposed method for determining the efficiency of a structure, taking into account the cost indicators of materials, can be applied in design practice. Recommendations for design are given to ensure the construction of the minimum cost and meet the requirements of strength and durability.

Emission spectra of apokamp discharge plasma jets in CO2, Ar, Kr, N2, and their mixtures have been studied. It has been shown that the emission spectra of the Kr–N2 mixture contain N2 and $$\rm{N_2^+}$$ bands, as well as Kr lines. The spectrum of the Ar–CO2 mixture is presented by bands of the Fox–Duffendack–Barker system and lines of the exited argon atom. In all gas media under study, the reduction of the molecular gas quantity leads to the transition from an apokampic discharge in the form of a diffusion jet developing from the current channel to a volume discharge with a strong transverse glowing. The experimental apparatus described in this work is proposed for use in laboratory investigations of spectral characteristics of transient luminous events observed in atmospheres of planets of the Solar System.

The evolution of the microstructure of nonstoichiometric niobium carbides NbCy (y = 0.77, 0.84, 0.96) and vanadium carbide V8C7 subjected to high-energy milling has been studied by the time-of-flight neutron diffraction method. It has been found that milled nanocrystalline powders have microinhomogeneous structure: two fractions with different sizes of particles have been identified in them. The content of the nanofraction is more than 90 wt %; the size of particles of this fraction varies from 90 to 250 A, depending on the composition of the initial carbide and the duration of milling. The size of particles of the second fraction is more than 2000 A. Anisotropic deformation distortions have been revealed. The mean size of coherent scattering regions and microstrains in nanocrystallites have been estimated.

Improving the food industry has led to a significant increase in the role of packaging in food production. At present, so-called "active packings" have appeared that have a positive effect on the product in contact with it, including through the use of antimicrobial additives. Work has been carried out on the use of a water-soluble form of chitosan in the technological process for the production of creamy butter "Krestyanskoe". The sample of chitosan was dissolved in drinking water with ascorbic acid (mass fraction 1%). The resulting chitosan solution was applied to the packaging material-aluminum laminated foil. Packaging is considered suitable for use after complete evaporation of moisture at room temperature from the surface of the material. The process of obtaining butter cream was carried out according to a conventional technological scheme by converting high-fat cream. It is determined that butter "Peasant" with chitosan is microbiologically more resistant than the control sample. The effect of the mass fraction of chitosan in the inner layer of the packaging material on the contacting product was experimentally established. It is established that the developed modified package allows to reduce the number of pathogens on the oil surface. In the course of storage, the control samples before the experimental ones showed the first signs of spoilage: an acidic unpleasant smell appeared and an aftertaste that sharply increased by the end of the storage period. The results of determining the organoleptic properties of the products correlated with physicochemical and microbiological indices. On the surface of the oil of the control samples, a more active development of yeast and mold fungi was observed. It is determined that the use of chitosan solution inhibits the development of mold fungi and yeast. The possibility of increasing the shelf life of butter "Peasant" in modified packaging by an average of 30% is proved.

The structural properties of nonionic spherical micelles with relatively large extensions of the interfacial layer are investigated, and the size dependences of their adsorption, interfacial tension, and chemical potential are obtained. Such familiar thermodynamic relationships as the Gibbs and Laplace equations, the differential equation for the chemical potential, and the concept of hydrophilic–lipophilic balance are used. The method is applied to micelles formed in surfactant solutions of a homologous series of tetraethylene glycol alkyl ethers. The region of the existence of micellar solutions and the structural characteristics of the interfacial layer of micelles are determined. The interfacial tension minimum corresponding to ideal hydrophilic–lipophilic balance in the micelle interfacial layer is detected. The chemical potential is negative over the range of the homologous series, and its derivative with respect to the tension radius is also negative.

The evolution of the microstructure of nonstoichiometric niobium carbide NbC0.77 powders subjected to high-energy ball milling has been investigated using time-of-flight neutron diffraction. It has been found that the nanocrystalline powders prepared by milling have a microinhomogeneous structure and contain two clearly identified fractions that differ from each other by the sizes of their particles. One fraction has a particle size of less than 60 nm, whereas the particle size of the second fraction exceeds 250 nm. The average size of coherent scattering regions and the value of microstrains in nanocrystallites, which accounts for the anisotropy of strain-induced distortions, have been estimated.

The purpose of this work is to study the factors that affect the positioning accuracy and find a way to determine the positioning accuracy of a mechatronic system. The paper investigates a model of a hexapod manipulator with six degrees of freedom. A mathematical model of the manipulator has been built. The study of the dependence of the positioning accuracy on the influence of external forces was carried out. It is concluded that manipulators of a parallel structure are applicable for light loads.

The features of the resistance of the support nodes of flexible reinforced concrete crossbars are considered taking into account the temperature effects. As the main area of work, a theoretical study of the influence of temperature effects on the strength and configuration of embedded metal parts and welds of the support nodes of prefabricated crossbars of various types is presented, which is an expression of the result achieved. The documents of the regulatory framework governing the design and construction activities in the Russian Federation, the existing constructive solutions of the support nodes, as well as the works of domestic and foreign scientists corresponding to the studies in this area are used. Research methods are structural and analytical analysis. Regulatory and scientific-methodological materials were studied, which made it possible to establish the parameters and factors affecting the constructive solution of the support nodes of flexible concrete elements. On this basis, proposals for improving the calculation and design solutions of support nodes are substantiated. Proposals have been developed for the calculation and design of support nodes taking into account temperature effects. It was revealed that the influence of temperature deformations significantly affects the operation of the support unit. The boundary ranges of temperatures and element sizes are determined at which the consideration of temperature effects is necessary. The features of the stress-strain state of the support node are clarified. Design recommendations are provided that provide strength and durability of the structure.

The structural characteristics of micelles from our previous work (Part I) are used to calculate the electrostatic energy of ions in the electric double layer on the surface of spherical ionic micelles in solutions of sodium n-alkyl sulfate homologues with the following number of carbon atoms in the molecule: n C = 8, 10, 12, and 14. This energy is found to depend on the thickness of the electric double layer and its average radius on the surface of a micelle, the aggregation number, the degree of binding of counterions, and the dielectric constant. The developed semi-empirical method is used to calculate interfacial tensions in spherical micelles for the said homologues in solutions at their critical micellar concentrations and T = 303 K. These values are split into the contributions from the hydrophobic and electrostatic components. The electrostatic component of the interfacial tension in spherical micelles is compared with the expression for the ion–ion repulsion energy to obtain the values of static permittivity (dielectric constant) in the surface layer of micelles.

Using the aggregation numbers of micelles and the effective sizes of hydrated surfactant ions and counterions of the first coordination sphere, we calculated the average geometric characteristics of the surface layer of ionic spherical micelles in solutions of the sodium n-alkyl sulfate homologues with n C = 8, 10, 12, and 14 carbon atoms in the molecule; in particular, we established 1) the size of the micelle core; 2) the thickness of the electrical double layer on the surface; 3) the mutual arrangement parameters of hydrophilic and hydrophobic ions; 4) the number of “free” water molecules and showed their dependence on the homologue number and the degree of binding of counterions.

We analyzed the atmospheric pressure plasma jet excited in air and nitrogen by a barrier discharge. The source forming stable plasma jets of length up to 4 cm in air and nitrogen is constructed, and its energy and spectral characteristics are measured.

The complex of hydraulic engineering installations includes five earthen dams. All facilities are of Class I. The diagnostic parameters of dam operation and technical condition monitored via in-situ observation for seepage mode, seepage strength, settlement, static stability, etc. generally meet design assumptions and safety criteria. Despite individual defects and signs of “aging” identified over the period of earthen dam operation, these are currently in a satisfactory and operable state. The long, 60-year operating period of the dams with no serious overhauls or emergencies has demonstrated the high reliability of the facilities, the correctness of the design and technological solutions adopted and implemented in the construction, and the high professional level of their operation in close cooperation with science.

The article is devoted to the problem of choosing the optimal parameters of reinforced concrete rectangular beams with single reinforcement. The analysis of the dependence of the cost of a single-span hinged-supported reinforced concrete beam on the selected parameters of its cross section under the action of a uniformly distributed load. The optimal range of cross-sectional parameters of reinforced concrete articulated beams (height, width, class of concrete and reinforcement, area and reinforcement pitch) was determined depending on the value of the uniformly distributed external load. Strength calculation of reinforced concrete beams is based on the traditional method given in the SR.63.13330.2018 “Concrete and reinforced concrete structures.” The cost of reinforced concrete beams was calculated under the influence of various uniformly distributed loads. The first option, where the width of the beams was constant and the section heights varied between 250 and 1000 mm. The second option, when the heights of the beams were taken equal, and the widths of the beams were in the range from 100 to 500 mm. The recommended height and width of the beam section for the specified value span in the investigated range of loads was set.

The ignition of a corona discharge on a tip electrode with a small radius of curvature in air at atmospheric pressure is studied. It is established that the initiation of the corona discharge in a highly nonuniform electric field at any voltage polarity is due to the formation of ball streamers at high (≥10 kV/µs) and low (≤0.2 kV/ms) rates of the tension increase in the tip—plane gap. It is shown that the current amplitude through the gap of the first streamers at a positive tip electrode polarity is approximately half of that at a negative polarity, and the frequency of their appearance differs by two or more orders of magnitude. It is established that the high pulse repetition frequencies at the same voltage across the gap lead to higher average currents through the gap and a larger observed glowing area in the case of the negative polarity tip electrode in the formation region of ball streamers.

Biphasic system of 2PSK-PAM signals and also definition methodology of reference voltage for separation of two arbitrary signal phases of the single carrier frequency are developed. This signal system owns by high-energy efficiency and ensures sample efficiency up to 13 bits per sample whereas spectral efficiency is equal to 26 bit/s/Hz referenced to in the radio channel band.

A laboratory setup has been created for modeling certain aspects of the initiation process of blue jets in the Earth’s atmosphere. With its help, the influence of an electric field on the apokamp discharge in air at pressures of 180-260 Torr was established. It is shown that the formation of a negatively charged zone located above the channel of a pulse-periodic discharge with a positive potential leads to both initiation and lengthening of the apokamps starting from the channel, and also reduces the voltage amplitude necessary for their formation.

The recent hypothesis about the initiation of red sprites in the Earth atmosphere in presence of metal atoms was verified. We have tested this hypothesis using Al, Cu, Fe, and W electrodes in laboratory apokamp discharges in air at a pressure of 45 and 760 Torr. Our experiments show that the electrode material does influence the apokamp dynamics. However, for Fe and W, compared to Al and Cu, the start voltage of an apokamp in pulse-repetition mode is higher and its length is shorter. The emission spectrum of apokamp discharges reveals lines of their metal electrodes. Thus, the experiments confirm the hypothesis on the contribution of metal vapors from burnt meteors to the initiation of red sprites in the Earth atmosphere.

In a single-barrier discharge with voltage sharpening and low gas consumption (up to 1 L/min), plane atmospheric pressure plasma jets with a width of up to 3 cm and length of up to 4 cm in air are formed in the slit geometry of the discharge zone. The energy, temperature, and spectral characteristics of the obtained jets have been measured. The radiation spectrum contains intense maxima corresponding to vibrational transitions of the second positive system of molecular nitrogen N2 (C3Π u → B3Π g ) and comparatively weak transition lines of the first positive system of the N 2 + ion (B2Σ + → X2Σ g ). By an example of inactivation of the Staphylococcus aureus culture (strain ATCC 209), it is shown that plasma is a source of chemically active particles providing the inactivation of microorganisms.