In this paper, we consider the applicability of the high-voltage surface flashover on ferroelectric ceramics in pulsed plasma thrusters. We made a thruster prototype based of high-voltage submicrosecond discharge. The power of the thruster is ~50 W, operation frequency is a few hundreds Hz, discharge voltage is ~20 kV, and weight about 400 g. The material of the discharge unit is barium titanate contained ceramics. The obtained values of thrust lie in the range 2-28 μN⋅s. The obtained velocities of the ion component of the plasma flow are up to ~100 km/s.

For four structural materials – copper UNS C10300, aluminum 1050 UNS A91050, steel 1006 UNS G10060 and glass Corning 7900 (Vycor) – the dependence of the elastic wave velocity determination error on the sample and exciter size ratio of the composite vibrator was studied by modeling a compound vibrator in the COMSOL Multiphysics environment. The modeled materials were taken from those available in the COMSOL MULTIPHYSICS library. The obtained results were compared with the results for similar domestic materials: aluminum D16, steel 45, copper M3 and borosilicate laboratory glass TS. The minimum size ratios were established, at which the elastic wave velocity determination errors do not exceed the values required under the experimental conditions. An experimental verification of the modeling results by the compound vibrator method was carried out on samples made of copper M3.

This article presents a study of the error components of the output signal in the gyroscopic channel of a small-sized inertial orientation and navigation system. The study of noise components was carried out on four copies of angular velocity sensors. The gyroscopic channel of this orientation and navigation system is implemented using the TG-100 MEMS angular velocity sensor from the Laboratory of Micro-Devices. The spectral composition of the random error components of the angular velocity sensor is estimated using the Allan variation method at room temperature. The intensity coefficients of various types of noise in the output signal of the angular velocity sensor are obtained and compared with its   standard characteristics. The accumulation of errors in determining the latitude, longitude and path of the gyroscopic channel of the inertial orientation and navigation system is estimated.

The article considers a beamforming device based on an aplanatic lens, which is formed on the basis of a polystyrene filling, enclosed in a waveguide system. The developed system has the ability to implement amplitude-phase distribution in a wide range of operating frequencies by feeding the input group of twenty-five ports, which ensure the implementation of beamforming on the output of thirteen ports. To improve the efficiency of the developed device, twelve ballast ports were integrated into the design of the beamforming device, which provide suppression of spurious emissions, as well as trajectories of electromagnetic wave propagation. The results presented in the work show that the proposed beamforming system allows for control of the characteristics of the amplitude-phase distribution in a wide frequency range, while ensuring minimal losses and high efficiency of electromagnetic wave transmission. To confirm the operability of the developed beamforming device, modeling was performed both as a separate system and as a beamforming system for the radar antenna system. The obtained results showed that the use of the beamforming system allows for scanning of the antenna beam in a wide range of operating frequencies, which is especially in demand in radar systems, as well as in the implementation of simultaneous frequency and amplitude-phase scanning by the antenna system.

Solar activity affects the operation of satellite systems, including GPS. At the same time, the most significant aspect for the operation of satellite systems is the ionosphere, characterized by electron concentration, ionic composition, and temperature. The purpose of the research is to consider the dependence between the solar activity, ionospheric disturbances and the quality of satellite communication; characteristics of the ionosphere, the critical frequency of the F2 layer during solar activity. To obtain the results of the study, we have used the following methods: analysis of methods for detecting solar flares, ionograms of reflections of high-frequency pulse signals generated by ionosondes, data processing by programming methods. Data for the analysis of solar activity were obtained on the website of the Laboratory of Solar Astronomy and Heliophysical Instrumentation of the SRI RAS and the ISTP the RAS Siberian branch. Ionograms presented on the website of the E. K. Fedorov Institute of Applied Geophysics were used to determine the critical frequency of the ionosphere layers. Through Python programming, using matplotlib, pandas and numpy libraries, graphs of critical frequency changes during the day were constructed. Original programs for data processing are presented in the paper. We have obtained graphs of changes in the critical frequency of the F2 layer, analyzed the states of atmospheric ionization, depending on solar activity. The analysis of the change in the critical frequency of the F2 layer over the period coinciding with the greatest solar activity is likewise presented in the paper. Ionograms have confirmed the formation of a sporadic layer in the same period. The results of the analysis show that the quality of GPS operation in conditions of magnetic storms decreases, an increase in navigation signal failures can be observed in the main phase of a magnetic storm with maximum disturbance of the geomagnetic field.

The article discusses the construction of hyperspectral systems based on the Fabry-Perot interferometer using matrix sensor that allow scanning to register images obtained from a given mode. The issues of expanding the scanning range in single-mode mode by combining light filters with wide detection zones and narrow-spectral detection zones formed by the Fabry-Perot interferometer are considered. The scanning parameters for several variants of single-mode operation using different interference orders are considered in detail, the results of their computer simulation are discussed, and recommendations for their application are given. The article also discusses in detail the issues of placing spectral images in RAM during the scanning process using a three-channel matrix sensor of the visible range of the spectrum. The corresponding tables showing the sequence of spectral images are given.

The purpose of this paper is to analyze operating system usage data and identify major trends in the usage of operating system architectures for the year 2024. The data used for the analysis is operating system usage data for the period October 2023 – November 2024. The result is to identify the major trends in the usage of architectures in the mentioned period. The results can be useful for predicting the future development of architectures and trends of operating system usage in science. The identified trends can be useful for predicting the future development of architectures and trends in the use of operating systems in scientific research, especially in the context of the development of artificial intelligence, where both highperformance hybrid architectures and flexible systems with a monolithic kernel and modular principles are in demand.

The paper contains a generalization of the nonrelativistic classical Hamiltonian dynamics of a system of interacting particles to the case of a relativistic theory. The interaction between atoms is taken into account within the concept of a covariant auxiliary field, which is equivalent to instantaneous interatomic potentials only in the nonrelativistic limit. It is established that the auxiliary field is a superposition of elementary fields, each of which satisfies the Klein-Gordon-Fock type equations. The real and complex forms of the relativistic Hamiltonian of a system of interacting particles are presented, taking into account the field degrees of freedom. The Hamiltonian contains three contributions corresponding to free particles, free fields of the Klein-GordonFock type, and interactions between particles and fields. Based on the variational formulation of problems of relativistic molecular dynamics, an exact closed relativistic system of equations is obtained, describing the evolution of a system of atoms and an auxiliary field within the framework of the Hamiltonian picture. An analysis of the qualitative properties of solutions of the equations of the system's dynamics is performed.

The main directions and areas of application of metal nanopowders in bonding technologies are considered. It is shown that when layers are deposited in the presence of tungsten nanopowder, the morphology of the deposited metal changes. Heterogeneous crystallization occurs in the presence of tungsten nanoparticles. The set concentration of tungsten nanopowder in the charge of the surfacing wire makes it possible to predict the grain size and hardness of the surfacing.

On the basis of the Lagrangian description of the system of particles and the field, the law of energy change of a system of point particles interacting with each other by means of a composite Klein-Fock-Gordon scalar field is obtained. The motion of particles was considered as nonrelativistic, while the field dynamics is always essentially relativistic in nature. It is shown that within the model of independent scalar fields the total energy of particles for the evolutionary time of the system decreases. Also the law of change of the total mechanical energy of the system of particles peculiar to classical mechanics is obtained. As an example, the double Yukawa potentials, typical for the model of simple liquids and gases, which are stable according to the Dobrushin-Ruel-Fisher criterion, are considered. It is shown that for such physically realistic potentials the rate of change of mechanical energy of particles is negative. Fundamental issues related to the research carried out, such as the phenomenon of irreversibility and the justification of Gibbs distributions, are discussed.

The paper is devoted to the study of the characteristics of magnetoelectric elements for a magnetoelectric synchronous generator. Two types of ME elements with different geometric dimensions of 70×12×0,54 mm and 30×10×0,54 mm were considered in the framework of the study. The influence of the dimensions of the generator magnetoelectric elements on the conversion efficiency is considered. The measurement results show the possibility of using magnetoelectric elements to create a generator. The article presents the characteristics of the elements in the resonant mode and non-resonant mode. Measurements have shown that at the resonant frequency, the output power can increase significantly. Thus, the output power at the resonant frequency of about 51 kHz was 0,9 mW. The results obtained demonstrate significant potential for using ME elements in energy generators, and the use of several such elements in the resonant mode will allow generating tens of watts of power, which makes such devices promising for powering non-volatile devices.

This article discusses the results of a study of thermal stability of samples of single-phase alloys Kh30N60M9 and Kh23N65M13 for heating conditions of samples at a rate of 5.0 °C/min in argon. The structural states of the alloy samples were obtained by water quenching, the alloy quenching temperatures were 1107 °C and 1135 °C, respectively. Based on the dilatometric analysis of the studied alloys, an estimate was made of the rate of change of the differential coefficient of thermal expansion – 𝛼(𝑇) = 𝑓´(𝑇) = 1/L0(dL/dT), where L0 is the initial length of the sample, T is the temperature, in the temperature range of 490–620 °C. The selection criterion was the smaller value of the change f´(T), which correlates with a lower rate of evolution of the specific enthalpy (stored energy) of the sample, confirming the smaller impact of the applied temperature, determining a more energetically favorable FCC structure of the solid solution of the alloy sample in the temperature range under study. Based on the results of this work, it was established that the structure of the Kh30N60M9 alloy is more stable to temperatures in the range of 490–620 °C, the thermal reaction of solid-phase transformation is less feasible, compared with the structure of the solid solution of the Kh23N65M13 alloy.

The review of the works of P. L. Kapitsa, V. A. Fock and L. A. Weinstein on the theory of integral equations of dipole antennas published in the period from 1959 to 1967 is given. The most significant results are noted, which are still relevant at the present time. The connections between the individual results are emphasized, and the outline of the theory of the kernel of the integral equation is outlined. This theory includes the decomposition of the kernel into a series by products of the Hankel and Bessel functions of the half-integer index, as well as the representation of the kernel through a hypergeometric function. The analysis of the computational experiment of V. A. Fock and L. A. Weinstein for a transmitting dipole was carried out, and a phenomenal coincidence with the results of other methods for solving integral equations with an exact singular kernel was obtained. A theoretical justification of this phenomenon is given.