The article is considered the wall stability of a steel cylindrical pre-stressed granary, compressed by the friction forces of grain and shell, taking into consideration the influence of the grain internal pressure, its elastic resistance from the inside and the elastic resistance of the pre-stressed shell outside. In this case, the initial and subcritical deflection of the shell is assumed to be axisymmetric, and the loss of the shell stability occurs with the formation of asymmetric deflection. The given solution of the problem allows to determine the magnitude of the critical efforts taking into consideration the influence of the grain internal pressure, its elastic repulsion, the magnitude of the initial deflections and the ratio of shell dimensions.

Keywords: stability calculation, wall stability, prestressing, internal lateral pressure, elastic rebound

metamaterials, microwave, antennas, diffraction, Maxwell equations, electromagnetic waves, the dielectric constant

Keywords: metamaterials, microwave, antennas, diffraction, Maxwell equations, electromagnetic waves, the dielectric constant

The authors propose to consider an interesting solution for finding real estate using GIS - technologies. This method can significantly reduce the time it takes to select a property. This article shows how the data processing capabilities of scientific computing tools for Python and the visualization and analysis capabilities of ArcGIS geospatial data can be used to build a model that generates a short list of houses that meet the needs and desires of potential buyers. And although the choice of a house is purely individual, there are a lot of common factors. Such as the total area, the number of floors and rooms, the presence of a garage and much more. Also, when buying a house, you are looking for proximity to services such as food, pharmacies, emergency rooms, child care facilities, parks, etc. You can use the ArcGIS API geocoding module for Python to search for such objects at a given distance around the house. This method suggests combining all the necessary conditions into one system, which will significantly reduce the list of real estate objects on the market and choose the most optimal options.

Keywords: GIS, ArcGIS, real estate, Python, maps, histograms, filter, DataFrame, spatial distribution, geocoding

The article is devoted to the possibility of applying the methods of successive approximations in the analysis of the instantaneous scheme of the traction network. The described approach allows to improve the accuracy of modeling dynamic modes of traction power supply sections, and also allows to significantly improve the process of modeling diagnostic systems and control of electric rolling stock at the design stage based on a more accurate model of dynamically changing input parameters of the traction network depending on their required level.

Keywords: traction network, instantaneous circuit, diagnostics, simulation, iteration

During the harvesting of crops, a significant amount of straw residues is formed, which can be used as raw material for subsequent processing. To assess the volume of straw suitable for processing for various needs of the agro-industrial complex, it is proposed to apply the Lotka-Volterra method. Using this method, it is possible to predict the formation of straw residues depending on the initial indicators during harvesting.

Keywords: straw residues, processing of straw raw materials, modeling, Lotka-Volterra method

This article is devoted to the study of the problem of power supply of low-power consumers distributed along the path of electric Railways AC, which can act as a system of sensors diagnostics of automated control systems of various objects located along the contact network. The main part of the article is devoted to the description of the primary model necessary for further consideration of such a method of electric power supply and experimental modeling.

Keywords: contactless power transmission, capacitive communication, power supply, contact network, electric Railways

Automation of agriculture is currently a promising and actively developing branch of robotics. At the moment, there are many foreign analogues offering ready-made solutions for automatic control of sowing crops. However, in Russia, most of the sowing is carried out on mechanized plants under the mandatory supervision of a highly qualified specialist in the maintenance of the plant.

Keywords: seeding control, microprocessor system, selection, seeding algorithm, system architecture, hardware, system structure, layout base, management methodology, import substitution

Cementation studies focus almost exclusively on the movement of carbon, described through the diffusion equations, often with constant coefficients and without regard to temperature. This approach does not allow, to take into account the further diffusion of carbon into the workpiece in a lower temperature range at the stage preceding quenching. The paper describes the modeling of the diffusion saturation of steel by carbon in the cementation process, taking into account the influence of temperature on the example of a numerical solution of the gear cementation problem using the COMSOL Multiphysics program. It was shown that the finite element mathematical calculation of the process of saturation of austenite with carbon during cementation gives good agreement with experimental data, and finite element analysis methods can be used for multivariate calculation of the carbon content in austenite after diffusion saturation

Keywords: carbon diffusion, carburization, COMSOL Multiphysics, numerical modeling, carbon distribution, carburization, Fick diffusion law, mass transfer, heat transfer, gear, finite element method

A method for the quasi-optimal synthesis of a multi-mode synchronization system based on the maximum condition of the generalized power function has been developed. The effectiveness of its operation in capture mode is demonstrated on the basis of mathematical modeling. The results showed high resistance to disturbances and a decrease in the synchronization error of the multimode system in the steady state.

Keywords: phase locked loop, combined maximum principle, multi-mode control

As a result of the analysis of normative documentation and soil fixing works, a brief historical review of the physicochemical methods of soil fixing was presented. Examples of the application of these methods in Russia and the world are considered.

Keywords: subsidence soils, cementation, soaking, heaps, mudding, subsidence, deformation, pit, soil consolidation

The article discusses the methodology and concept of situation rooms. The methodology and concept of situation rooms has a long history. As a first step, one can recall the methodology of a classic board in Cretaceous technology. Smart boards have now emerged, where hardware and software are present alongside the light pencil, to display various kinds of information. The second level in cognitive modeling systems is the collective panel display of various information products. Finally, the third level of situation rooms implies a significant development of the software and hardware of the decision-maker support complex. The high level of complexity of the third stage in the creation of the situation room is the creation of developed mathematical support in brainstorming tasks, as well as in the provision of analysis of weakly structured systems. However, while our work deals with the creation of a theoretical model of semantic identification of various scenes, situations of the person making the decision.

Keywords: Information collection and display system, decision maker, electronic counteraction

During the year, depending on the latitude and climatic zone, the number of thunderstorms and their intensity vary greatly, these parameters decrease to the Northern latitudes due to a decrease in humidity and temperature and, accordingly, a decrease in the probability of forming conditions for the formation of convective and thunderstorm clouds. The article deals with the mechanisms of dangerous effects of lightning discharges. The electric parameters of the discharges for thunderstorm processes in the atmosphere were studied using data from the geophysical monitoring center of the FGIBU "VGI", which includes a network of sensors of the automatic thunder-gauge finder - the range finder LS8000. The results of the analysis of the recording of ground-discharge currents and the time of their growth obtained during the period of its operation are presented. The authors determined the statistical distributions of the lightning current amplitude. It is established that the discharge parameters in different regions differ and can change with time. This means that for the effective operation of lightning protection systems and the implementation of measures to ensure life safety during thunderstorms, it is necessary to monitor the lightning situation in each individual region.

Keywords: atmospheric electricity, lightning discharges, lightning guides, lightning protection measures, life safety

The technologies for producing ultrafine copper powders are examined. The influence of various parameters on the processes of electrocrystallization of particles is studied. Various mechanisms for producing particles in the presence of water-soluble polymers are presented. The ultrafine copper powders obtained using different electrolysis modes. A review of advanced electrochemical methods for producing ultrafine copper powders with the addition of various stabilizers particle growth, further ways of developing the technology of these technologies are highlighted.

Keywords: ultrafine copper powders, electrocrystallization, production methods, particle stabilization, water-soluble polymers, double electric layer, vibrocathode

This article may be of interest to researchers who are designing new machine systems for felling-area works with autonomous energy supply. A methodology based on the decomposition method for creating an simulation functional model of a system consisting of a mobile wood chipper for felling-area works and a mobile energy module is proposed. The machine system of interest is an original technical solution. It consists of an autonomous energy supply module with powered by wood fuel external combustion engine and a logging machine for the production of wood chips. The functioning equipment units of the system is simulated using the MATLAB Simulink dynamic simulation environment. For the convenience of experiments, the use of LabVIEW virtual instruments is proposed for setting input and control parameters, as well as displaying output parameters. The input, control, disturbing and output parameters of each functional block of the system are described: gas generator, external combustion engine, electric generator, uninterruptible power supply, electric motor, propulsion device, wood chipper unit, hydraulic manipulator. It is supposed to use this simulation model to justify the main parameters of the autonomous system for the production of wood chips, as well as the further development of an automated control system.

Keywords: fuel chips, wood fuel, unmerchantable tree, simulation model, LabVIEW, Simulink, mobile chipper, autonomous power supply, logging

In publication overflows and leaks of oil products are considered on petrol filling stations. The materials used to collect overflows and leaks of oil products on petrol filling stations are indicated. Disadvantages of sand and properties of silica clay are considered. The petroleum was used for carrying experiments to collecting of oil products by sand and silica clay. The experiments were carried out and the data on changes in the mass of petroleum remaining on the samples (particles of silica clay, particles of sand) from initial mass of the samples (before contact with petroleum) were received. The assumption was made about the possibility of using silica clay instead of sand to collect overflows and leaks of oil products in urban environment.

Keywords: overflows, leaks, oil products, petrol filling station, sand, silica clay, urban environment