Using the methods of Rutherford backscattering, X-ray phase analysis, transmission electron microscopy and diffraction, the features of structural and phase transformations in layers of Ni–Pt–V alloy with a thickness of 30 nm on the surface of monocrystalline n-Si(111) under rapid heat treatment with incoherent constant-power light flux from quartz halogen lamps directed to the reverse side of the substrate for a duration of 7 s until a temperature of 350 to 500 °С is reached have been established. It is shown that under these conditions of heat treatment, the formation of Ni_xSi_y layers occurs, characterized by varying degrees of ordering (epitaxy). It was found that rapid heat treatment at a temperature of 350 °С is accompanied by a redistribution of nickel and silicon atoms to the composition ∼Ni₃Si at the film-substrate interface with a decrease in the proportion of Si towards the surface with the formation of domains of the hexagonal (P321) phase of the β-Ni₃₁Si₁₂ silicide epitaxial to the substrate. Rapid heat treatment at temperature from 400 to 500 °С leads to a further diffusion redistribution of the reacting components to a composite composition of ∼Ni₅₀Si₅₀ and the formation of an orthorhombic (Pnma) phase of NiSi silicide having a transrotational degree of epitaxy. In this case, the ordered growth of NiSi silicide occurs on the epitaxial domains of β-Ni₃₁Si₁₂, which persist at the interface between the silicide and the substrate up to a temperature of 500 °С.

By combining sol-gel and hydrothermal deposition methods on glass substrates, thin-film coatings of zinc oxide doped with nickel and aluminum were obtained. Studies of the structure and composition of the films using scanning electron microscopy, energy-dispersive X-ray and Raman spectroscopy have shown that they consist of close-packed zinc oxide crystallites doped with impurity atoms of nickel and aluminum. Resistive type photodetectors were manufactured based on the films obtained. It has been shown that when irradiated with ultraviolet light with a wavelength less than 400 nm, the resistivity of the structure decreases from 190–210 to 7.5–8.0 Ohm⋅cm. The achieved response time for the rise of the light pulse is 48 s, while the decay time is ≈700 s.

A model has been developed and patterns of mutual influence of the electrophysical parameters of a transistor structure with a two-dimensional channel, due to the self-organization of charge and capacitive properties under conditions of charge instability, have been obtained. Transition metal dichalcogenides are considered as a material for a two-dimensional channel. The influence on the electrical parameters of a transistor structure with a two-dimensional semiconductor channel of the band gap of the channel material, the thickness of the gate dielectric, and the capacitance of interface states is considered. It is shown that under conditions of instability caused by an increase in the capacitance of interface states, the dependence of the electrochemical potential, electron concentration and quantum capacitance on the potential of the field electrode has an abrupt form. The results obtained are explained by the fact that, under conditions of instability, an increase in the capacitance of interface states leads to a mismatch between the electrical neutrality condition and the Fermi-Dirac statistics at certain val ues of the gate potential due to the limited nature of the density of states of the two-dimensional channel, which leads to the manifestation of a charge imbalance. The resulting effect is similar to the metal-semiconductor transition and can be attributed to bistable critical phenomena. The developed model and the results obtained can be used in computer-aided design systems for the element base of micro- and nanoelectronics.

The article provides a theoretical analysis of the interaction of dual-frequency and modulated electromagnetic waves with anisotropic media above hydrocarbon deposits and computer modeling. The frequency range of changes in the electrodynamic parameters of the environment above the deposit with the manifestation of anomalies in the electric field strength has been established. Recommendations are given for the use of modulated signals to improve the accuracy of determining the boundaries of hydrocarbons based on measuring the phase characteristics of the surface impedance of the medium above the hydrocarbons. A hardware and software complex has been developed for recording the electric field strength in the modes of receiving probing signals and the natu ral radiation of hydrocarbon deposits. Experimental studies were carried out in gas fields of Syria. Methods are shown to increase the information content of the developed method and equipment when carrying out prospecting work at hydrocarbon sites. The research results can be used in devices for identifying oil and gas deposits in geophysics.

When radar stations operate, radio pulses of varying intensity are received at the receiver input depending on the type of target, range to the target and other factors. Adjusting the receiver gain is necessary to adjust its sensitivity in such a way as to provide the best reception of signals with amplitudes that vary widely. The article discusses a logarithmic automatic gain control system, analyzes its advantages and disadvantages compared to classical automatic gain control system, and performs its simulation in the graphical programming environment Matlab/Simulink.

Current transformers (reflectors) based on unipolar (field-effect) transistors are being studied for their effective use in integrated circuit technology. However, their widespread use is limited due to a number of features that these studies are aimed at overcoming. These features are associated not only with geometric and electrical factors, but also with temperature. Attention is drawn to composite unipolar structures, which turned out to be effective for the formation of thermostable currents. Recommendations of a circuit nature are given and the supply voltage is optimized to minimize it for the practical implementation of this mode. For the transformation of thermostable currents, original circuit solutions suitable for integral execution, based on composite bipolar-unipolar structures, were proposed and analyzed, which made it possible to change these currents both up and down without noticeable deterioration of their basic parameters.

Remote assessment of the dielectric characteristics of the earth’s surface is in demand for solving various industrial tasks. The article discusses the theoretical and practical aspects of measuring the dielectric const ant of the Earth’s surface when it is irradiated with a radio signal in a two-position system from unmanned aerial vehicles. The required depth of penetration of the probing radio signal under the surface is achieved using the UHF band and oblique irradiation under conditions of complete (pseudo-complete) refraction of the electromagnetic wave at the air-surface boundary. The novelty of the proposed approach lies in the oblique irradiation of the Earth’s surface with a horizontally and vertically polarized radar signal, followed by registration of amplitudes and phase shifts of interference wave oscillations.and finding the Brewster angle by the parameters of the interference wave. The practical application of this approach is to measure the moisture content of agricultural soils and determine the strength characteristics of sea ice.

5G systems have many interesting advantages, that’s why their popularity around the world is grow ing rapidly. However, it is necessary to evaluate the potential negative impact of electromagnetic radiation from devices of these systems on human tissue in order to ensure the safety of the health of the human body. The present study was aimed at assessing the degree of exposure of the human head to electromagnetic radiation from a microstrip antenna at millimeter wave frequencies and improving the performance of this antenna to ensure human health safety. During the study, using the CST Studio Suite 2021 software package, the following was done: a microstrip antenna emitting at the frequency of 38 GHz was simulated; the efficiency and performance of the simulated antenna for 5G system devices was assessed; the layers of the human head were designed and simulated to analyze the impact of the simulated antenna radiation on it; the absorption specific rate of radiation energy from the simulated antenna by each layer of the human head was estimated. Based on the results of the study, approaches to reducing the SAR value of the human head were proposed and theoretically justified. These approaches consist of adding various materials to the microstrip antenna as protective barriers.

Simulation of the operation of a hardware-software complex for studying the impedance-metric charact eristics of a biological fluid is presented. The impedance-metric parameter was calculated on a previously simulated measuring cell with the objects under study in the COMSOL Multiphysics program. The microcuvette is designed according to the standard of the Litoplast-Med Type A 2.5 ml cuvette, which is subsequently used to test the mo deling results. The results of the study can be used to further prevent threats to the normal course of pregnancy and birth outcomes. The obtained modeling parameters were used for comparison with the results of experimental testing.

The task of constructing test sequences difference characteristics was studied. Its relevance for generating controlled random tests and complexity in finding difference measures for the case of symbolic tests were substantiated. The limitations of using traditional distance characteristics to obtain a measure of the difference between test sets are shown. For the binary case, a new measure of the difference MH(T_i, T_k) of two character test sets T_i and T_k is defined based on the classical Hamming distance. This measure represents n components, each of which is determined by the Hamming distance between the binary set T_i and the pattern T_k cyclically shifted by v bits. The main properties of the proposed dissimilarity measure are reviewed and its effectiveness for classifying test candidates when generating controlled random tests is shown. Experimental results are presented that confirm the effectiveness of the proposed difference measure.

A combined method for constructing and operating a two-level mobile self-organizing network is proposed, based on the distribution of nodes across the transport and access levels, transferring them to peer-topeer and infrastructure operating modes, respectively. The method is distinguished by dividing the load sources of each transport node into two frequency collision domains, which increases the probability of successful random access to the transmission medium. This leads to a doubling of the used frequency band, but reduces the likelihood of frame loss and increases network throughput while maintaining the ability to self-organize and scale. The proposed method makes it possible to organize a two-level mobile self-organizing network with higher throughput compared to a single-level one operating in peer-to-peer mode, with the same frequency band and coverage area. Moreover, the effectiveness of the proposed method increases with the increase in the number of access nodes, since it leads to a decrease in the number of transport nodes in the transmission channel and the probability of data frame loss.

As part of solving the problem of a comprehensive assessment of the state of the biosphere, the urgent question is to develop a geographic information system that will not only store large amounts of data of various types, but also provide the ability to use methods for processing and analyzing this data, numerical modeling me thods and intelligent decision-making methods. The basis for the functioning of a geographic information system is a database and a database management system. Therefore, the main task of the research was to select the database structure and database management system technology for developing software for a geographic information system for a comprehensive assessment of the state of the biosphere. An analysis of the types of data used in the geographic information system was carried out, which showed that a system for a comprehensive assessment of the state of the biosphere should provide the ability to work with all types of spatial data that may be required to solve problems of various nature in the field of environmental monitoring. According to experimental data, the MariaDB database management system was selected, which showed the best performance when working with a geographic information system for online monitoring of the state of environmental components in the city of Orsha and the Orsha region.

The article shows the possibility of extracting energy from vacuum using an electric oscillator model based on Casimir’s effect with split mirrors rotating relative to each other. Since, according to existing physical concepts, unilateral extraction of energy from vacuum is impossible, the task goes into experimentally detecting tangential forces in Casimir’s effect during the relative rotation of the mirrors that slows down this rotation. 

The article presents the structure and model of an Internet of Things network that can be used for remote rapid detection of Alzheimer’s disease. A local server model of the Internet of Things network has been created for personalized medical care on the client side. The model corresponds to the characteristics of the Internet of Things network: interconnection between devices, real-time communication, data processing and analysis, the use of various protocols for data transfer and exchange. When building the model, the Flask framework was used to create an application instance with a trigger condition for sending data from a smartphone to a local server via an HTTP request. The local server receives the HTTP request sent by the smartphone and processes the data. The result of the procedure is transmitted through the MQTT protocol to the MQTT client that has been subscribed to certain topics, i.e., the smartphone. Taking into account the selected structure and configuration of the Internet of Things network device, a complete model of this network was built, which can be applied to various applications. The functions and performance of the model are verified through experiments.