The paper considers the characteristics of cloud convection obtained in the course of computational experiments on the basis of a three-dimensional physical and mathematical model of convective clouds, which takes into account in detail the microphysical processes of nucleation, condensation or sublimation of water vapor, coagulation and accretion of precipitation particles, accumulation of volume electric charges, and an increase in the electric field strength. clouds due to charge separation processes occurring during the rapid freezing of large supercooled drops, accretionary growth of cereals and hailstones. Based on the data of numerical modeling using the noted model, the location in the volume of the microstructural parameters of thunderstorm clouds (water content and ice content), space charges, electric field strength, radar reflectivity in the centimeter range, and other parameters at fixed times of cloud evolution was investigated.

Keywords: convective cloud, cloud microstructure, cloud electricity, numerical three-dimensional model, radar reflectance, electrical coagulation

The article discusses the causes of accidents in water supply and sanitation systems. methods for improving the quality of drinking water in the construction and reconstruction of water pipes, the use of new materials to reduce breakdowns on networks are considered. the analysis of the durability of pipelines made of various materials is carried out, according to which it is concluded which material is the best in use for installation work. frequent destruction of pipes occurs from an aggressive environment, so a comparative analysis of various materials from which they are made: polyvinyl chloride, polypropylene, reinforced concrete, cast iron and fiberglass. due to poor-quality cleaning, there are environmental problems that occur when using old structures, lack of funding. It is concluded that fiberglass pipes can serve as a high-quality material.

Keywords: quality water, replacement of pipelines, water supply and sanitation, corrosion and destruction of pipes, new polymer material, pipe materials, comparison of pipes made of different materials, service life, wastewater treatment, ecology

The article presents scientific and technological aspects of improving grain cargo transportation in the southern region with the participation of railway transport. Based on the analysis of volume indicators of transportation, existing delivery technologies, scientific provisions in the studied area, the directions of development of grain cargo transportation logistics are identified. The prospects of increasing the supply of grain cargo to the ports of the Azov-black sea basin are considered. The review of logistics technologies of grain cargo delivery to the ports of the Azov-black sea basin by rail is performed. New information tools have been developed to support decision - making when optimizing cargo flows and developing grain delivery plans under multi-Agency conditions. A system of temporary criteria for evaluating cargo flow distribution plans at the port road polygon has been formed .The article presents statistics on purchasing innovative rolling stock for the specified volumes of grain cargo transportation.

Keywords: railway transport, export, logistics, management, technology, transportation organization, outsourcing, utilitarianism, egalitarianism, distribution of cargo flows, optimization, information technology, mathematical modeling

One of the effective ways to increase the information secrecy of a constellation of low-orbit spacecraft (LVS) is the use of a satellite authentication system (SAS). In order to reduce the time spent on determining the status of the satellite, as well as to increase the fault tolerance of the identification system, in a number of works it is proposed to use the codes of the polynomial system of residue classes (PSCS). This paper presents a methodology for constructing a fault-tolerant authentication system for a spacecraft, which is based on exchange operations implemented in PSKV codes. Using exchange operations, that is, changing the number of informational and redundant bases, it is possible to ensure the possibility of maintaining the operational state of the identification system in the event of a sequence of failures, as a result of which the level of information secrecy of the NSA will not be reduced.

Keywords: satellite authentication system, polynomial system of residue classes, exchange operations, method of building a fault-tolerant identification system

The results of optimizing the composition of concrete based on aggregates from crushed concrete are presented. With the help of mathematical and natural modeling matched the composition of the expanding agents sulfoaluminate type, the optimal percentage of components of the modified cement required for producing a material with improved performance characteristics, the mathematical model construction and technical properties of the concrete and the kinetics of their changes to take into account the time factor and strength and weathering.

Keywords: mathematical modeling, expanding additive, factor experiment, influencing factors, level of variation, experiment planning matrix

The article is devoted to the study of the interaction violations of electric locomotives current collectors with a contact wire, accompanied by the appearance of an electric arc. In order to further develop the system of technical diagnostics of current collection disruptions, accompanied by arcing, it is necessary to study the nature and parameters of the processes that occur with these disruptions. The main part of the article is devoted to the determination of the geometric parameters of the heating zone of the contact wire material by a movable electric arc, followed by an analysis of the applicability of the obtained dependences and their normalization. The description of the research area, the essence of the problem and the main statements of the technical diagnosis of current collection disruptions is given. The nature of the distribution of heat in the cross-section of the contact wire is shown. Based on the nature of the process and plane geometry, the parameters of the heating zone of the contact wire material are obtained: the area of the heating zone and the depth of the heating zone. Limitations in the application of the obtained dependencies are given.

Keywords: electric transport, overhead contact system, contact wire, current collection disruption, electric arc, current collection with arcing, thermal wear, softening, diagnostics

The consideration and study of the process of functioning of the offices of the company were the following objectives. Determine the quantitative dependencies of the input flow of patients and unserved requests (refusals). To conduct the sensitivity analysis. Build a basic model of a dental company as a simulation model (input model) that provides targeted variation of input parameters, and a linear programming model (output model) that processes simulation results and provides data on the degree of sensitivity of the model to changes in its parameters. Compare two simulation models of a dental company with different numbers of doctors. Determine the most effective model. Determine a combination of management variables in the optimization model that takes into account the amount of estimated lost profits due to rejection of applications, and based on this, make a conclusion about the need to hire additional employees, thereby increasing the profitability of the dental company. To achieve these goals, the following tasks were solved. A simulation model of a dental company as a Queuing system in the GPSS language was developed and studied. It is determined under which parameters the model is most effective. An analysis of the sensitivity of the model to changes in its parameters is performed. Numerical Monte Carlo methods were used to investigate this issue. We have developed a custom application in the VBA object-oriented programming language that allows you to determine for a certain period of time, starting with how many failures, you should hire an additional doctor, so that the company's profit is maximized. The practical value of the proposed model lies in its flexibility, complex nature, and consistency in the organization and technological regulation of the company's main systems and business processes. The model of a dental company has a sufficient degree of universality, as it can be used in any branch of the service sector. more complicated when you add players. The term "truel" we understand the rivalry three players. They are assigned some values of accuracy the probabilities of eliminating the opponent in one shot. At each stage of the game is chosen by the active player (the selection rule active player either randomly or by prior agreement between the players about their participation). The active player chooses an opponent to eliminate or passes the course. Developed mathematical models for different formulations of the conditions of the game (random or fixed choice of the active player). For each model are analyzed based on the probability of winning in the "truly" of accuracy, based on randomly generated program values. Comparing analytical solution and simulation, we see that they have the same answers. For large dimensions similar games analytical method requires complex calculations, so an acceptable alternative is the simulation method. Data research nahegelegenen in political and judicial practices, as well as analytical tools for the study of the theory of evolution.

Keywords: simulation model, Queuing systems, GPSS World, linear programming model, Monte Carlo numerical methods, VBA

The use of spacecraft identification systems can increase the informational secrecy of low-orbit spacecraft constellations. However, existing methods of recognizing "friend or foe" do not provide high cryptographic strength, and authentication protocols with zero disclosure are time-consuming. This drawback can be eliminated through the use of Polynomial Residue Number Systems (PRNS) that allows parallel computing in the protocol. Therefore, the development of a high-speed authentication protocol with zero disclosure is an urgent task. The purpose of the work is to reduce the time required to calculate the status of the satellite through the use of PRNS

Keywords: authentication method, spacecraft authentication protocol, Polynomial Residue Number Systems

"The article is devoted to solving the problem in the field of development of methods and means of automation of evaluation of training efficiency on computer simulators, which are used for the training of operators of production processes. Approaches to assessing the effectiveness of training are given in many scientific studies on the creation and application of computer simulators. However, the problem of automation of the process of this assessment on the basis of the simulators themselves is not sufficiently considered. The evaluation methodology (based on mathematical statistics methods) and the prototype subsystem of the computer simulator complex were proposed to solve the indicated problem. They reduce the effort of the expert responsible for performance evaluation. Output results can be used for training operators in educational organizations. The reported study was funded by RFBR according to the research project № 18-38-00835. "

Keywords: computer simulator, mathematical statistics methods, efficiency of training process, automation of training process

A survey of the frame-panel building was carried out, in which ecowool was used as the heat-insulating material. A study was made of the moisture state of wooden frame walls and attic floors. Ecowool samples were taken from various sections of the wall. No mold was detected on material samples. In this case, the sorption humidity was not more than 16%. The results of laboratory tests of ecowool showed high persistence of density and coefficient of thermal conductivity during long-term operation. Tests were conducted to determine the effect of moisture on the change in the physical and technical properties of ecowool. The research results were processed by statistical methods. As a result of the study, it was found that moisture does not accumulate in the ecowool layer of the examined frame walls and attic flooring, but goes out through the insulation and elements of the building envelope. The conducted studies allow us to predict the preservation of the heat-shielding properties of ecowool during operation for a long time

Keywords: ecowool, durability, sorption humidity, density, coefficient of thermal conductivity

The huge part of Russia territory is located in the permafrost zone. Mastering of this area is important step for Russia, because the mining is developing at a rapid pace, and mostly oil and gas. There is its own specificity in the construction of buildings and structures on permafrost. Peculiar properties of foundation in the permafrost zone are considered in this article.

Keywords: foundation, permafrost, thermosyphon, oil storage, oil and gas industry, drilling, ammonia

The work is devoted to the study of the main aspects of the use of expert systems in the metallurgy industry. An overview of current production problems is given, as well as prospects for the development of automatic decision-making systems based on formalized expert knowledge using modern data processing tools

Keywords: production processes, metallurgy, control actions, expert systems, technological personnel, production indicators, software implementation, modeling, interference, training complexes

The article presents a program of comprehensive construction and technical expertise of the structures of an industrial building. The features of the construction and technical expertise of the structures of the agricultural warehouse of mineral fertilizers are described. An algorithm of the sequence of actions for the technical expertise of the structures of the object is developed. Measures have been developed to repair and restore the working condition of damaged structures

Keywords: construction and technical expertise, defects, bearing capacity, structural repair, property management

The publication is devoted to the task of developing a demo-genetic model of the adaptation of pests to transgenic and hybrid agricultural crops, taking into account the type of taxis. An assumption is introduced that the dynamics of hybrid agricultural crops can be investigated using demo-genetic models. A description of the problem is given in accordance with the characteristics of the growth of biomass of agricultural crops and the dynamics of pests, as well as taxis species. The modeling of the processes of fast and slow taxis depending on the behavior of pests at a particular point in time is described in detail, taking into account the type of their genotypes that affect the acquisition of mutations. The paper describes the features of the physiological structure and life cycle of insect pests, affecting the prediction of their spatial concentration and, accordingly, the prediction of productivity; the possibilities of their application in mathematical modeling.

Keywords: demo-genetic model, taxis, transgenic agriculture, hybrid, pest, biomass, diffusion

This work outlines software packages that are capable of dealing with nonlinearity of the analyzing structure. Brief introduction of the software and its beginning in the history. Also explained the difference of linear and nonlinear analysis performed on the structure. Defined which software packages are for media and analyzing problem (structure). Similarly, descriptive study was done to understand advantages and disadvantages of main analyzing tools ANSYS, ABAQUS, SOLIDWORKS. In addition, the work looked into which one of the mentioned tools have its own distinguish functions. Finally, the results data of all three software were compared with each other.

Keywords: nonlinear analysis, numerical analysis, ANSYS, ABAQUS, SOLIDWORKS