When selecting technology options for additive manufacturing, it is important to be guided by a list of basic requirements for manufactured parts, powder material features, and the range of equipment specifications. To develop the most effective solution, pilot testing of the technology will be required to determine the preferred process modes that ensure the required quality, cost, and manufacturing time. Accordingly, for such industries, it is important to develop a model that describes the stages of additive manufacturing. In this regard, this paper is devoted to considering the issues of optimization, planning, and management of additive manufacturing technology based on multiple criteria for selecting the most effective technology that involves optimal loading of production facilities. The proposed model introduces indicators that characterize adaptation and allow arguing the practical benefits of using 3D printing technologies. Comparison of process routes by these indicators allows choosing a specific manufacturing route. Having selected the manufacturing option, it is possible to calculate the most efficient placement of products on platforms, as well as to develop a suitable sequence of execution of the main manufacturing operations in order to minimize costs and time expenditures. It was found that the use of the proposed model allows to reduce the manufacturing time of a batch of products by approximately 2.5%. Thus, the proposed model can be useful in additive manufacturing to reduce downtime of installations and speed up the release of products.

Keywords: production organization, productivity assessment, equipment reconfiguration, machine loading, automation, multi-product production

Tests to determine the seismic stability of elements of pipeline systems, in particular pipeline fittings, are included in the list of those necessary to confirm the operability of the element. In this study, a stand was developed for testing to determine the seismic stability of butterfly check valves, which are a type of pipeline fittings. A finite element analysis was carried out, data on maximum deformations, stresses and displacements of structural elements were obtained, and the response of the installation table to seismic impact was calculated. The resulting displacement values of the table structure do not exceed the limit values specified by the technical requirements and do not lead to distortion of the structure or destruction of joints, which makes it possible to move from design to manufacturing and commissioning of the stand.

Keywords: vibration tests, seismic resistance test bench, pipeline, pipeline valves, swing back gate, mathematical modeling, finite element method, strength calculation, simulation modeling, stress-strain state

The paper presents the results of numerical experiments on solving systems of linear algebraic equations (SLAE) with discharged matrices by the LU decomposition method, the Jacobi method, the Gauss-Seidel method, the modified Gauss-Seidel method and the modified Jacobi method with a relaxation parameter ω. In the course of numerical experiments on the solution of (SLAE) with test discharged matrices of various dimensions using the MATLAB package, it was found that the best results in the time of solving the problem were obtained by the modified Gauss-Seidel method with a relaxation parameter ω = 0.5 or a given accuracy of solutions ε= 10^-6. In the future, this method was used to calculate the integral characteristics of the functioning of distributed information processing systems for various practical applications.average system response time to user requests).

Keywords: distributed information processing system, a system of linear algebraic, equations, sparse matrix, LU decomposition, Jacobi method, Gauss-Seidel method, relaxation parameter

Due to the constant increase in production, new structural materials development and growing rates of non-renewable resources consumption, the issue of increasing the machinery resource is urgent. Thus, it is necessary to develop technologies for spraying coatings that improve the functional characteristics of products, in particular, impact strength, microhardness, resistance to wear, corrosion and other environmental factors by modifying the surface layer structural-phase state. These technologies application is necessary in strategically important industries, such as machine tool manufacturing, aerospace, automotive, shipbuilding, chemical, energy, etc. This article is devoted to the facility development for multicomponent nanocomposite coatings sputtering. The design and commissioning of such a facility requires a high time and material resources investment. In this regard, it is necessary to use modern computer software systems that allow simulating multiphysics processes that take place during the facility operation. The simulation of the cathode-anode unit was carried out. Based on the simulation results it was shown that it is necessary to take into account the physical processes in the interelectrode region when designing the plasma spraying unit, since the resource of the cathode-electrode unit and the productivity of the sputtering process directly depend on the parameters of the discharge and the resulting plasma jet. Thus, high temperature and current density, as well as the arc spot abrupt movement, lead to increased wear and failure of the copper nozzles. The maximum values of the temperature and velocity of the plasma jet during spraying were 32000 K and 1800 m/s, respectively.

Keywords: plasma spraying, multicomponent nanocomposite coatings, multiphysics processes, mathematical modeling

The paper describes the main agents, with their components and process diagrams, of the developed simulation model of the functioning of the distributed information processing system, created in the AnyLogic software environment. A method for constructing models with self-similar traffic is described. The article also presents a method for obtaining real (reference) indicators of the average response time of the system to user requests. The results of numerical experiments on the created models of the functioning of distributed information processing systems with self-similar traffic are presented. The main conclusions about the performed experiments are presented.

Keywords: distributed information processing system, self-similar flow, average system response time, simulation, object-oriented concept, agent-based and discrete-event modeling

The paper presents a formalized statement of the problem for conducting a comparative analysis of the efficiency of distributed information processing systems. Reliability, technical-operational and technical-economic indicators of the distributed information processing systems functioning were selected as the main efficiency criteria. At the conceptual level, this problem was reduced to the problem of vector optimization, the solution of which is associated with significant difficulties. An alternative approach to solving this problem is proposed.

Keywords: distributed information processing system, vector optimization, availability factor, average system response time, fault tolerance coefficients, total downtime cost

In this article, in terms of the language queueing networks, the problem of finding the optimal values for average system response time for requests from all users for distributed information processing systems that are implemented based on the architecture "file-server", double-tier and three-tier architecture "client-server" at a fixed downtime cost, including the cost of idle users the value of the idle transmission channel, and the cost of downtime service nodes. An algorithm for solving this optimization problem is presented.

Keywords: Distributed information processing system, file-server architecture, two-level client-server architecture, three-level client-server architecture, state space, average system response time, loss cost, stationary probabilities

The problems of the operation of buildings on subsidence soils of the Rostov region are considered. A brief analysis of the methods used to consolidate the soil. Concrete examples of the use of cementation and silicatization of soil bases in the development of reconstruction projects for buildings in the cities of Shakhty and Taganrog, Rostov Region are given. An integrated approach to the choice of technology for fixing the soil base of reconstructed objects is proposed, which provides for the simultaneous consideration of the following factors: - basic physical and mechanical properties of soils; - mineralogical composition of soils; - change in the state of the soil base during the operation of the building (local decompression, erosion, chemical and mechanical suffusion, etc.); - chemical composition and groundwater level, forecast of their change; - terrain, the danger of activation of landslide processes; - the presence of retaining walls and other retaining structures in the zone of influence, assessment of the loads on them in the process of consolidation; - the technical condition of building structures of the building, including its underground part and the blind area; - the status of the reconstructed object. With special care and precaution, it is necessary to choose the technological and design parameters of soil consolidation for cultural heritage sites of federal or regional significance; - technical and economic indicators.

Keywords: subsidence of soils, strengthening of soils, fixing of soils, cementation, silicatization, Geology, construction, cultural heritage object

In this article, in terms the language of queuing networks, the problem is formulated finding the optimal value the average response time of the system to the requests all users for distributed information processing systems implemented on the basis of the file-server architecture, two-level and three-level client-server architecture with a fixed cost of downtime, including the cost downtime for users, the cost of downtime for a data transmission channel and the cost downtime for service nodes. An algorithm for solving this optimization problem is presented.

Keywords: distributed information processing system, file-server architecture, two-level client-server architecture, three-level client-server architecture state space, average system response time, loss cost, stationary probabilities

This article describes a software complex simulation, which allows you to evaluate the impact of the main integrated indicators of the distributed information processing system on its reactivity, taking into account the properties of self-similarity of traffic, TCP/IP data transfer Protocol, and various architectures. The software package consists of software-implemented mathematical models of distributed information processing systems based on file-server, two-level client-server and three-level client-server architecture, as well as the algorithm of distributed information processing system objects distribution. The platform AnyLogic PLE was used as a software tool.

Keywords: a distributed information processing system architecture "file-server", two-tier architecture "client-server", three-tier architecture "client-server", simulation, self-similar traffic, agent-based modeling, discrete event simulation, system dynamics

This article formulates the main stages of the process of constructing analytic-numerical models of functioning of distributed information systems with non-exponential (self-similar) input traffic of requests. Each separate stage of modeling, at the conceptual level, is reduced to solving a certain class of mathematical problems. The basis of the mathematical apparatus for obtaining the basic integral characteristics of the quality of distributed information systems functioning lies in the method of analyzing the average values ​​of networks of queues. The basic relationships for calculating the reactivity of distributed information systems operation are given.

Keywords: distributed information system, discrete self-similar process, Hurst parameter, Pareto distribution, queuing network, Kendall classification, Polacek-Khinchin formula, average system response time

In this article, using the decomposition approximation based on Norton's theorem, the authors present a mathematical model of the distributed information processing system based on the local computer network on file-server architecture with arbitrary functions of the distribution of service time of requests in the network nodes. A conceptual model of an equivalent two-node Queuing network is constructed, in which the first center of the network coincides with the i-th center of the original network with an arbitrary law of distribution of the duration of requests maintenance, and the second (composite), which is the equivalent of the rest of the network, has exponentially distributed service time, which depends on the number of messages in it. The basic mathematical expressions for calculating the intensity of service in the composition center, as well as expressions for calculating the average response time of the system to user requests are also presented.

Keywords: distributed information processing system, file-server architecture, decomposition approximation, queueing network, compositional center, intensity of service, the average response time of the system to user requests, conceptual model, normalizing constan

This article describes a software package to solve the problem of optimal placement of information resources-fragments of a distributed database on the nodes of a distributed economic information system by the criterion of the minimum average response time of the system to user requests. The software complex consists of software-implemented mathematical models of distributed systems of processing economic information on the basis of file-server, two-level client-server and three-level client-server architecture, as well as optimization algorithm. The developed software product also allows to make experiments for obtaining and subsequent analysis of the dependence of the reactivity of distributed systems on such integral characteristics as the dimension of the problem, the intensity of the formation of requests by users, the speed of message transmission through communication channels, the speed of reading, the speed of writing and processing in the nodes, which allows to implement a more rational organization of the computational process in the system. The software was implemented in C#, the NetFramework 4.6.1 platform, using the Microsoft Visual Studio 2017 Community development environment.

Keywords: economic information system, distributed information processing system, architecture "file-server", two-level architecture "client-server" three-level architecture "client-server", the global balance equation, a closed exponential queueing network

This article describes the stages of implementing the program to solve the task of calculating the average response time of a distributed information processing system to user requests and an algorithm for the optimal distribution of information relations over the nodes of a distributed information processing system implemented on the basis of a file server architecture and a two-tier client server architecture, with and without locks. The procedure for constructing the initial data for modeling is described: the elements of the matrix of the initial distribution of information resources (relations) over the nodes of the distributed information processing system, the elements of the matrix of information interrelation between the requests of users of the distributed information processing system and the information resources themselves, the elements of the matrix of probabilities for generating queries by users. A procedure has been developed and programmed to significantly simplify the calculation of the normalizing constant, and accordingly the average response time of the system to user requests. The results of numerical experiments are presented

Keywords: Distributed information processing system, file-server architecture, two-level client-server architecture, nonlinear combinatorial optimization, generator of equiprobable choice, Jordan-Gauss method, normalized constant, average reaction time of the syste

In this article to solve the problem of optimal distribution of information resources over the nodes of distributed inorganic system according to the criterion of minimum of the medium time, the response of the system to the requests of the users an original heuristic algorithm is proposed that uses the notion of databases as points of a mulltidimensional space, but about nodes in which these bases are placed as clasters. The resuts of numerical experiments are presennted depending on the architecture of the distributed system used and on the method of ensuring data integrity. Numerical experiments showed rather high efficiency of the proposed algorithm.

Keywords: Distributed information system, distributed data base, local computing system, mass service network, non-lineare combinatorial optimization, query generation, a matrix of probabilities for generating queries by users, a matrix for distributing relations a