The article proposes a thermodynamic approach that allows us to more accurately represent the flow modes of quasi-stationary gas through a long step gas pipeline . It takes into account the peculiarities of the operation of side gas venting devices of small-caliber automatic guns on the principle of automatic operation. We use a combination of the main characteristics that represent the operation of such systems under difficult loading conditions and high temperatures. These are mainly gas consumption, heat transfer losses, gas flow rate, improvement of the approach to the solution of ensuring the appropriate parameters to ensure the reliable operation of the relevant technical systems with the possibility of recommendations after appropriate tests of such products.

Keywords: step gas pipeline, side gas outlet device, gas flow, thermodynamic parameters, heat loss, filling period, gas consumption, automatic weapons systems

A device for compacting the snow mass using the vibro-vacuum compaction method has been designed. Calculations were made in the SolidWorks 2018 software product. The calculation of the estimated economic efficiency of compaction of the snow mass using vibro-vacuum compaction was carried out.

Keywords: cleaning of the adjacent territory, vibration-vacuum compaction, installation, calculation of economic efficiency

Physical wear and tear can be determined either by studying with the help of instruments, or relying on regulatory and expert methods. The first helps to obtain reliable indicators of physical wear, but to obtain it requires less materials. Normative and expert methods - the second make it possible to identify the degree of wear with less accuracy, but it requires a small investment of materials and time. Two similar methods include the "Methodology for determining the physical deterioration of civilian buildings", which was created by MINKOMHOZ of the RSFSR, as well as Departmental building codes 53-86 (r) "Rules for assessing the physical deterioration of residential buildings." The problem of lack of information in the absence of the possibility of personal inspection of the evaluated structure, and, in addition, the obsolescence of the methods makes it difficult to use them. In this case, it is logical to use calculation methods.

Keywords: corrosive wear; reliability; durability; classification

The article considers the introduction of serveying as a new complex analysis of real estate objects, its concept, directions and main structures.

Keywords: serveying, expertise, integrated approach, real estate, construction, efficiency, quality, analysis

This article provides a theoretical description of the vibration turbulization process. It is shown that with constant physicochemical properties of the system, the volumetric mass transfer coefficient in the liquid phase during vibration turbulization depends on the mixing power and gas content.

Keywords: vibration impact, mass transfer, gas content

The paper studies the liquid-phase epitaxy processes of a new material of infrared optoelectronics - indium arsenide doped with bismuth using a stepwise thermal field. An analysis of the phase equilibrium during the growth of a solid solution is carried out. The possibility of the formation of a mesostructure (modulation of the composition along the growth coordinate) is shown. The problems of defect formation in composite layers grown from a melt are considered. Ways of decreasing the dislocations density in gradient layers are discussed. A relatively simple method for controlling the thermal field of temperature in the crystallization zone and a new technological procedure for the sequential crystallization of solid solutions with a mesostructure have been developed.

Keywords: solid solutions, liquid-phase epitaxy, indium arsenide, mesostructure, stepwise thermal field, dislocation generation

Increased concrete strength due to early loading is one of the priorities of concrete technology. Many articles contain data on changes in compressive strength after early loading. The first person to test early concrete loading was Satalkin. He tested bridge supports for static and dynamic loads. The results of his work became the basis for further research in the field of early loading of concrete. The objective of this work is to study the tensile strength in bending after early loading and to check the influence of the orientation of the samples under load. Also we considered the effect of active mineral additives on this parameter. The object of study is samples of cement-sand dough prepared on a Portland cement binder of various manufacturers. We noted a difference in the strength characteristics in bending by changing the orientation of the samples when testing them after early loading. The maximum increment of strength is noted in a plane perpendicular to the direction of compressive force. The use of a mineral additive with the replacement of a fraction of cement gave the attenuation of the observed effect.

Keywords: anisotropy of strength properties, early loading of concrete, cement composite, flexural strength, mineral additive

The types of Autonomous stationary energy-cooling systems designed for complete isolation of special objects operating without connection with the atmosphere are Considered. A technical solution is proposed that allows increasing the efficiency of the energy-cooling system, reducing the consumption of process water due to its partial recirculation for cooling the engine of an Autonomous power plant, as well as increasing the period of complete isolation of the object.

Keywords: energy-cooling system, underground facility, military infrastructure, complete isolation mode

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 deals with current methods of evaluating the organization and management in construction under conditions of uncertainty. The typology of the failure process is given, which determines the scenario of the crisis development at the enterprise. A model of forecasting and management in a crisis is proposed, and the conceptual aspects of building this model are considered. It is proposed to improve the enterprise management system based on the analysis of the economic component as a temporary function. Recommendations are given for improving the existing organizational forms of enterprise management.

Keywords: construction organization, organizational and technological solutions, reliability assessment, construction quality assessment

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 article is devoted to the development of a mathematical model of a vulcanization boiler, namely, the temperature control loop inside the boiler. The mathematical model of the boiler was obtained by the Rotach method in the form of a transfer function. Simulation modeling was performed in the VisSim software tool. The adequacy and stability of the model is proved and the numerical values ​​of the quality criteria of the transient process are obtained. The resulting model is intended to determine the optimal settings of the regulator of the vulcanization process control system.

Keywords: transfer function, vulcanization boiler, transient, software, system order, vulcanization process, control, calculated transfer function, delay time, sleeve

The problem of creating advanced technologies and equipment to increase the efficiency of forest regeneration by seedlings and seedlings of forest crops has not been finally solved and is an urgent task today. Of particular concern is the lack of patented equipment for the renewal of forests by seedlings and seedlings of forest crops that are competitive in the domestic and foreign markets. The purpose of the research is to prove that the basis of the search for solutions to the synthesis of patentable solutions that increase the efficiency of forest regeneration by seedlings and seedlings of forest crops can be laid the formation of a knowledge base on the basis of patent information search, and the use of a functional structural and technological analysis. In the course of the work, a classification of the main areas of patenting in the mentioned area was carried out and it was shown that the use of the proposed approach allowed the authors to develop and patent a number of new technical solutions for the equipment of forest regeneration by seedlings and seedlings of forest crops.

Keywords: forest regeneration, seedling, seedling, patent, synthesis of patentable solutions, functional-structural-technological analysis

The article deals with the dynamics of an ion beam in a tandem laser mass-reflectron. The software package that implements the mathematical model of the ion beam motion is based on the "large - particle" method.it takes into account the influence of the spatial charge field and the interaction of ions with the field of the electrodynamic system. The potential distribution in the device nodes is obtained by numerical solution of the Laplace equation using the mathematical package Freefem++, which implements the solution of partial differential equations by the finite element method. The absence of inhomogeneity of the electric field inside the reflectors is shown. A series of numerical experiments has been carried out, which has shown the convenience of using the finite element method for numerical solution of problems of electrostatics and ion optics, as well as the effectiveness of using numerical modeling to develop and optimize the parameters of mass spectrometers.

Keywords: large particle method, laser mass spectrometer, particle-particle method, electrodynamic system, Runge-Kutta method, laser plasma, ion beam, focusing system, triangulation, gas-forming impurities, time-of-flight mass spectrometer