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
Rail transport plays a key role in the transport of passengers and goods. The high demand for effective means of flaw detection of high-speed rails, which is an important component of railway safety, is justified by the constantly growing number of vehicles and their speed . Failure of elements of the railway infrastructure entails huge losses. In this regard, the analysis and forecasting of the state of elements of the railway infrastructure is an urgent task. This article analyzes modern methods for diagnosing the state of a rail track from a mobile bogie or a conventional locomotive. A method for diagnostics of a rail track is proposed, based on registration of vibrations near the rolling surface of rails and processing these signals using neural networks.
Keywords: rail flaw detection, wheel surface, algorithm, IMM, MEMS, control system, inertial sensor, rail defect, contactless measurement
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
The article discusses the problems that arise in pattern recognition related to clustering and data abstraction. Detailed typical data clustering options. The problem of data transformation by vector quantization with the least error is given. A competitive training system for an artificial neural network based on a growing neural gas is described. Using the method of growing neural gas, an improved algorithm of a self-learning artificial neural network of competitive training is proposed. The criteria for completing clustering using the adaptation criterion as a stop criterion are defined. Examples of data clustering by an artificial neural network using the method of growing neural gas are given.
Keywords: clustering, artificial neural network, computer modeling, pattern recognition, self-learning intelligent systems
The theoretical aspects of crystallization of multicomponent solid solutions are discussed. Antimonoid heterosystems in which bismuth is present are considered, a component that largely determines the photoelectric properties of the studied materials. The features of establishing the equilibrium of the liquid and solid phases in the process of crystallization of these systems are considered. The laws of the thermodynamic behavior of heterosystems in the conditions of gradient liquid-phase epitaxy are established. The results of experimental studies on the growth of solid solutions of multicomponent bismuthides on InSb substrates are presented.
Keywords: solid solutions, migrating liquid phase, indium antimonide arsenide, gallium bismuthide, binary pair, recrystallization, quasicrystalline structure
In this work, we simulated the graphene-MnO composite structure based on minimizing the electron density functional. The analysis of the processes of rearrangement of the interface surface SLG (monolayer of graphene) - MnО (111). In this case, the interface was subjected to hydrogenation. The distribution of the effective charge on graphene is investigated. A decrease in the work function of the charge carriers during hydrogenation of the interface is established.
Keywords: effective charge, graphene, passivated surface, density functional, interface, work function, energy gap, band structure
The search for technological solutions for the organization of lean production at precast concrete enterprises was carried out. Options for rational use of rock crushing screenings as a filler and filler for self-compacting fine-grained concrete are considered. The optimal dosage of limestone crushing screenings in the composition of fine aggregate for the preparation of self-compacting mixtures has been determined. It was found that the enrichment of very fine Sands with large fractions of Sandstone crushing screening in an optimal amount reduces the intergranular voidness and reduces the water demand of the fine-grained mixture.
Keywords: lean production, rock crushing screenings, optimization of grain composition of aggregate, self-compacting fine-grained concretes, superplasticizer based on polyaryl and polycarboxylate esters
The analysis is made of the use of expanded clay gravel in cement-sand mortar in order to reduce ice at the boundary between the pile and the mortar. The application of expanded clay concrete in block-modular buildings is considered. Lightweight design and reduced heatloss are proven.
Keywords: diversification of management, production diversification, financial and economic purposes of a diversification, technological purposes of ensuring flexibility of production
The results of the study of fluctuations of the center of mass of the car UAZ "Hunter" during its movement on the support surface with different height of road irregularities: asphalt-concrete surface and off-road are given. The study uses Simulink simulation.
Keywords: Center of mass fluctuations, vehicle, simulation, Simulink
Organizational conflicts are a natural and integral part of any process. In modern control theory, it is proposed to use various adaptive control structures to solve such problems, in particular, with reference or configurable models in the control loop. A cognitive model of adaptive management of organizational conflicts with a configurable model in the management loop is considered. Embedding the model in the control loop allows you to integrate information about the dynamics of process characteristics. Based on information processing, a variant of controls for de-escalation of the conflict is proposed. The model in the organizational conflict management loop is essentially an intelligent conflict situation analyzer. It presents options based on the accumulated and processed information within the framework of known precedents for their solution. The core of such analyzers is a simulation model based on the system dynamics paradigm. The built simulation model allows you to evaluate and predict the impact of factors, ways to stabilize and manage organizational conflicts, taking into account the main parameters. In accordance with the concept of adaptive management, the model can be configured for the current values of the conflict situation parameters and, in accordance with the already tested options, can offer management in a specific situation. The use of the system dynamics paradigm in the model for building an effective forecast is focused on the strategic level of management.
Keywords: cognitive model, simulation model, conflict, escalation, contour, management, de-escalation, organization
The article is devoted to research of thermofluctuation processes of insulating materials of power cable lines (SCR) of electric power systems. It was established that an artificial neural network (ANN) can be used to compile a forecast of the temperature regime of a current-carrying core with an accuracy of 2.5% of the actual value of the core temperature. The comparison of the predicted values with the actual ones allows us to talk about the adequacy of the selected network model and its applicability in practice for reliable operation of the cable system of power supply to consumers. The development of an intelligent system for predicting the temperature of the core SCR contributes to the planning of the operating modes of the power grid in order to increase the reliability and energy efficiency of their interaction with the integrated power system.
Keywords: Neural networks, thermofluctuation processes, insulation materials, neural network architecture
The article describes the specifics of OOP concepts implementation in the open source projects that contain address book model in comparison to OASIS UBL Party Reference model. The open source software analysis is performed using the formal criteria for evaluating the matching between open source project models and reference model based on quantitative characteristics, conceptual graph transformation and cluster analysis. First, the scope coverage, elaboration factor and structural connectedness were calculated based on model parameters. Second, the domain models were represented as conceptual graphs and they were compared based on semantic equivalence. And third, the model was clustered into four subdomains, and quantitative characteistics were evaluated separately for each cluster. Based on the experimental results of model analysis the authors propose methods to reduce the conceptual mismatch between reference model and project models.
Keywords: OOP, semantic analysis, reference model, OASIS UBL, conceptual graph, cluster analysis
This article discusses the problem of network authentication of a client when a functional web-system consists of various services, each of which is represented by a separate site. Particular attention is paid to Single Sign On technology - a single entry point as a way to achieve centralized authentication. A comparison of tools that provide a single input is given, and a conclusion is made about the best of them. Based on the research, the author proposes the Gluu single entry point server as a server that satisfies all the requirements of the functional service system presented in the example, and also able to work within the framework of popular authentication protocols.
Keywords: functional service system, authentication, authentication protocol, single entry point, single entry point server, comparative analysis
The article deals with the issue of modeling by the finite element method of the penetration of the communication tunnel under the operating multi-lane highway demand microtonneling, horizontal directed drilling and construction under the protection of the screen from pipes
Keywords: Tunnel, collector, finite element method, microtonneling, horizontal directional drilling, motorway, case, reinforced concrete, metal pipes, settling mule
The article discusses the results of the calculation of reinforcement in monolithic reinforced concrete floors. The subject of the study is the reinforcement of the slab section located next to the column. The study was carried out by setting up a computational experiment. Modeling was performed in software systems: Revit, Sapphire and Lira-CAD. Finite element models were calculated in Lira-CAD software. A total of 7 series of samples were calculated. The samples are a fragment of a monolithic reinforced concrete floor of a civil building. Investigated factors: triangulation parameters; the presence or absence of absolutely rigid bodies in the node. The authors performed a comparative analysis of the results of a computational experiment. It was found that for the most correct and economical selection of reinforcement in models without the use of AFL, it is desirable to take the triangulation step in the slab equal to the side of the column section or more than this value by no more than 15%, since an increase in the size of the finite elements leads to an underestimation of the reference moment and the resulting area calculation longitudinal working reinforcement. With this approach, the value of the maximum moment, and, therefore, the area obtained by the calculation of the reinforcement will be 6% higher, which makes it more preferable, although it increases the complexity of creating a finite element circuit.
Keywords: BIM technology, reinforced concrete, girder-free overlap, reinforcement, triangulation, finite element, reinforcement selection, computational experiment, Rewit, Sapphire, Lira-CAD