Vol 24, No 1 (2016)

Articles
Analysis and modeling of the existing protocols used in time synchronization of the regional power-grid information systems
Gubanov N.G., Raguzin A.S.
Abstract
The author continues to research the information-systems time-scale synchronization to solve the problem of maintaining a single time at the power facilities of the regional grid company. The analysis of the algorithms and principles of the existing time protocols (NTP, SNTP, PTP) widely used in packet-switching data-communication networks is done to determine their satisfying the requirements and operation principles of the examined complex time-synchronization system. The paper presents the comparative characteristics of these protocols; conclusions are drawn taking into account the requirements of internal guidelines concerning the development of ICS to be met by the tasks of information-systems time-synchronization in power grid companies
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):7-14
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System of automatic control of gas-oil separator control the density of the oily mixture
Zelenskiy V.A., Zhmurov D.B., Shchodro A.I.
Abstract
One of the priorities of the domestic economy is to increase resource efficiency in oil production and refining sector. Development of automated control system of gaz-oil separator is directed to solving this important national economic tasks, which leads to the relevance of the work performed. The candidate system is different from the existing analogue elements control the density of the oily mixture and was developed for the first time. The detailed proposed algorithm and the scheme of automation, the selected types and names of sensors, actuators and intelligent means of measuring information processing. Developed software in ladder logic Ladder Diagram, the structure of the user menu and view the main control screen. Introduction of system of automated management gaz-oil separator will significantly improve the quality of the phase separation in the oily mixture on the existing process equipment.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):15-23
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Application of the software system of Ansys finite-element analysis for computer modeling of residual stress of head s for vertical-grids devices
Ivanyakov S.V.
Abstract
The paper deals with the bearing capacity of heads with vertical contact grids (VGD). The main structural parameters affecting the strength properties of the head are found. A model of a VGD head is developed, its adequacy being checked. As the modeling result, the dependency of a contact-point ultimate load on the mass-exchanger design structural parameters is obtained. The maximum permissible distance between the gussets is determined which allows the head`s cost to be reduced while retaining its required strength.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):24-29
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Assessment of the efficiency of providing electronic services by municipal agencies
Orlov S.P., Ivanova N.Y., Savelyev D.S.
Abstract
The paper deals with the problem of assessing the efficiency of municipal agencies which provide e-services for the public. Information processing is characterized by a large and diverse nomenclature of electronic services. The scheme of information interaction of subjects and objects involved in this process is given. For an objective assessment of the operating-environment efficiency it is proposed to use the Data Envelopment Analysis methodology. The efficiency criterion and the model in the form of a linear programming problem are formulated. On the basis of standard statistical reports on public services, a set of input and output parameters of assessed objects is defined. To further increase the efficiency of the agencies it is proposed to build artificial objects and define the practical efficient frontier. The model of a linear-fractional programming is offered. The conditions for the existence of solutions in the presented model are determined.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):30-35
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The development of models and optimization criteria for an inventory management automatic system on the basis of the tools of the classical automatic- control theory
Sergeev .V., Novikov A.A.
Abstract
The paper treats of the possibility of applying the mathematical tools and methods of classical automatic-control theory for analysis and synthesis of a company's manufacturing and business processes management. The description of a mathematical model of a company’s safety stock management in the form of discrete-time functions is given taking into account such factors as delays in delivery or unexpected increase in demand. The criterion of solving the problem of a company’s optimum inventory management is defined. This criterion takes into account various additional expenses caused by the stock increasing or decreasing in comparison with the demand value.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):36-40
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Neural network realization in the spreadsheet
Hrisanov N.N.
Abstract
The paper deals with the realization of a neural network in OpenOffice.org package. The scheme of a neural network is given, the choice activation functions, the calculation scheme of criterion quality gradient in the course of training is justified. The software structure is discussed. The software includes the modules of experimental-data preliminary processing and normalization, interaction with the database, a neural network initialization and training, dialogue management, and a diagnostics module. The results of a neural-network application for the solution of a recognition task are given. The results enable the justification of the choice of activation functions, sample size for the neural network training, and the high level of recognition.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):41-47
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System estimation of innovative activity of regional economy
Tcapenko M.V.
Abstract
In this article the questions of synthesis of global assessments of innovative activity on an example of the Samara Region economy. As a method of systematic evaluation selected generic way of ranking based on the method of multi-criteria evaluation of efficiency Data Envelopment Analysis. The work implemented multi-criteria evaluation procedure and the ranking system of innovative activity in the region over the time interval. The information base for assessment procedures are the local state statistical indicators characterizing the scope of research and innovation at the regional level.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):48-55
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Parametric modeling and optimization of data cable core insulation extrusion control process
Chostkovskiy B.K., Stroilova M.A., Mitroshin Y.V.
Abstract
Extrusion technological process optimization method, which is implemented by correlation and spectral analysis of cable characteristics with parameterization of its results, is developed. Parameterization of infinite-dimensional evaluations of correlation and spectral analysis for analytical optimization realization and imitation modeling of extrusion technological processes control systems is performed. Two methods of approximation are used: approximation of evaluations by typical expressions and spectral density splitting with obtaining of shaping filters transfer functions.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):56-68
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Using spatial-time division of instantaneous values for determining harmonic-signals parameters
Melent’ev V.S., Ivanov Y.M., Sinitsyn A.E., Peskova A.S.
Abstract
We discuss a new method of measuring the parameters (RMS of voltage and current, active and reactive power) by the instantaneous values of harmonic signals which provides their spatial-time division. In contrast to the known methods based on the formation of additional voltage and current signals and identifying the moments of signal zero crossing, the implementation of the method involves the auxiliary signals formation only in the voltage channel. A block diagram of the measuring system realizing the method is proposed. The analysis results of the method error caused by the deviation of the real signals from the harmonic model. The results obtained enable the selection of the appropriate hardware depending on the measurement-accuracy requirements.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):69-76
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Modelling the correlation measuring instrument of an independent-device velocity vector
Sviridov V.P., Lazarev Y.N.
Abstract
The questions of constructing the correlation system for measuring the velocity vector of an underlying-surface image motion independent device when the speed of the device rotational motion is not great. Computer modeling of current- images detection efficiency under different levels of noise pollution and light for the two models of comparison metrics is done: the classical one, based on the correlation functions computation, and the logic one, used to compare the binary images of logic functions. We examine and discuss a model of the difference-correlation measurement method, and show its advantages. The advantages of using the recursive-pyramid approach and logic metrics for finding quickly the correlation extremum and for the system’s adaptation to the required accuracy are singled out.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):77-86
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The induction heating system in the production of technical silicon
Bazarov A.A., Navasardyan A.A.
Abstract
A set of issues on modeling of electromagnetic and thermal processes in the induction heater for the formation of a magnetic field, compressing the melt and preventing the contact of silicon in the liquid phase with the walls of thermal insulation. In determining the inductor’s power and voltage frequency, the temperature-dependent nonlinear properties are taken into account. The design parameters which enable cooling to the solid state under induction heating conditions are searched for. To solve the problems of electromagnetic and thermal processes modeling used a finite-element formulation taking into account the nonlinearities and the fusion latent heat. Different realization variants of the inductor which enables covering the melt’s entire volume or its part in case of continuous movement after the silicon solidification are examined.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):87-95
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Simulation of a combined rectifier-loaded generator
Zubkov Y.V.
Abstract
The problem of studying the dynamic modes of a combined rectifier-loaded generator (CRLG) is stated. The mathematical description of a generator to be used as an independent low-power source is given. The CRLG differential equation based on the equations of a generalized electric machine in the dq axes, which are associated with an inductor, are obtained, and then the coordinate transformations for the exciter and generator are done. A simulation model taking into account the saturation of the CRLG magnetic circuit with opposite-poles magnetic fields, the generator’s work for the rectifier load together with the battery is developed. The saturation calculation is done by input into the model the parameters of the generator’s idling and the exciter’s short-circuit. A relay voltage regulator and a smoothing filter are included into the model to control the input voltage and to improve it. The CRLG transient modes, in particular load surge and shedding, and switching on the excitation in an open system, are examined. The analysis of the current and voltage waveforms has shown that using a filter reduces the ripple to an acceptable level, and the generator is quick to respond to the impact through the control (excitation) and disturbance (load) channels.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):96-102
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Determining the resistances of induction motor by catalogue data
Kotenev A.V., Kotenev V.I., Kochetkov V.V.
Abstract
The method of calculating parameters for equivalent circuit of the induction motor with squirrel-cage rotor is developed. These parameters are necessary for the analysis and evaluation of the engine in various modes because background information of the manufacturer does not contain of these parameters. Nominal values of active and inductive stator and rotor resistances are derived from the three solutions of algebraic equations, which are based on the equations of nominal electromagnetic power, maximum electromagnetic power and the nominal reactive power dissipation. Resistance of circuit magnetization is determined from a consideration of the balance equation full power of this branch. Method of calculation of these parameters is represented as the block diagram.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):103-109
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Reinforcement of distribution networks to improve stability of voltage and to decrease power loss
Kubarkov Y.P., Kulaev I.S.
Abstract
In modern systems, electricity deregulation and restructuring have created an increased interest in the planning of distributed resources, as they play an important role in improving operational efficiency. Distribution systems are constantly faced with ever-increasing demands of consumers and, as a rule, work on the verge of overload. When the distribution system in critical conditions, the integration of distributed resources increases the reliability of power supply by increasing the voltage stability and reduce power loss. Thus, in order to improve the quality and reliability of power supply networks, must be provided with an optimum size and location of the allocated resources.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):110-115
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The minimum time control of electromechanical positional system
Kurgan V.P., Pankin A.A.
Abstract
The optimal laws of current change and speed of electromechanical positional system which provide minimum movement time for a demand movement and demand heat losses are defined in this article. The result is the formula for the time minimum during which the positional system performs the demand movement. The obtained armature current and speed extremals of positional electro drive in short-time duty can be implemented by using of high-torque direct current motors which are regulated by controlled converter with adjustable current-limit.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):116-121
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Mathematical model of heat- and mass-transfer during fractional condensation of hydrocarbon vapor in presence of inert gas in a vessel with vertical contact grids
Lesukhin M.S., Kriuchkov D.A.
Abstract
Creating of a mathematical model of fractional condensation in a vessel with vertical contact grids (FCCG) is described in the paper. A flow diagram of vapor, inert gas, condensate and coolant contact in a segment (dh) of FCCG vessel is proposed. The equations of heat and mass balance in a segment (dh) of FCCG vessel are analyzed. Differential equations set describing temperature distribution, as well as heat and mass flows in a FCCG vessel is given for the cases of condensation of a vapor-gas mixture, multicomponent vapor-gas mixture and condensation with additional pumparound.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):122-129
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Reinforcement of the weld seam of the rail joint
Aleksentseva S.E.
Abstract
Creation of a new method of a reinforcement of a weld seam by an explosive doping at the expense of a high-speed penetration of particles. Definition of suitability of a method for a reinforcement of welded joints of rails. Creation of a method for raise of operation factors of rail welded joints. Use of an expedient of a reinforcement of a weld seam by means of effect of superdeep penetration the particles, implemented at the expense of a high-speed throwing of the discrete particles, accelerated by energy of explosion of an explosive charge. In the offered expedient for a throwing of particles the explosive charge is used superimposed. On an explosive charge bottom face the stratum of particles is superimposed. The explosive charge is disposed on an outside surface of a welded joint. On a rail joint surface the stratum of an easy material for fracture preventing is had. Experiments of a throwing of particles of wolfram on a steel (0.8 % С) are made. Concentration of the implanted particles of wolfram, hardness and microhardness of a steel is spotted. Usage of an superimposed explosive charge implements a throwing of particles by means of a shock wave at an angle. It provides more uniform concentration of the implanted particles. The offered method implements a high speed throw and the superdeep penetration of particles from solid materials and chemical combinations in metals. Raise of hardness and microhardness of steel (0.8%С) is attained. The offered method can be used for a mass reinforcement of welded joints of rails of railway tracks.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):130-137
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The polarization characteristics of metal materials
Katz N.G., Vasilyev S.V., Kalinkina D.S., Konovalenko D.V.
Abstract
The problems of the electrochemical study of metal surfaces of steel and magnesium alloys, used as protectors. For research used potentiostats P5827M brand and IPC-prO. It presents the polarization characteristics of the steel surfaces and magnesium sacrificial alloys used to protect oil tanks from corrosion damage. It is shown that a steel plate, which is made from the bottom of the tank and the magnesium alloy serving for protection from corrosion damage bottoms have similar corrosion characteristics at high salt content in the produced waters.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):138-142
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Repairing drill-pipe tool joints by facing
Miheev D.A.
Abstract
The paper concerns the optimization of the technology for repairing drill pipes by facing. The methods of tool joints repairing are surveyed. Various protective media while performing facing are analyzed. The selection of a preheating mode as well as the optimum thickness of facing layer is made. The physical and mechanical properties of repaired drill-pipe tool joints are assessed, analyzed the microstructure of the base metal is analyzed. The measures devised using the results of this research will guarantee the high quality of repaired products
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):143-149
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Assessment of accuracy of the approximate regression models for solidification of the continuous ingots
Yakubovich E.A.
Abstract
The paper deals with a statistical evaluation of the accuracy of the previously synthesized approximate models of regression type, obtained from tabular data on a continuous casting modes of deformable aluminum alloys in an electromagnetic mold. As determined by the characteristics of the process used liquid metal depth wells liquidus and solidus, the size of a two-phase-band in the center of the ingot. The calculations set of indicators, including Spearman rank correlation coefficient, multiple correlation coefficient and operability coefficient for regression equations confirm the performance models for the practical use. These calculated dependences allow a quantitative forecast of the joint effect of casting speed and cooling intensity to the expected value of the depth of the wells and the size of the two-phase zone of the ingot with access to the adjustment of real technological parameters.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):150-155
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Electrodynamic processes in induction heating
Yeghiazaryan A.S., Zimin L.S.
Abstract
The paper discusses the features of induction heating of bodies with sharply changing curvature of the surface, one should take into account the volume density of the electromagnetic field which manifests itself in the form of an electrodynamic interaction between the inductor and the slab. It results in strong vibration and noise exceeding health standards. These investigations enable making recommendations which take into account electrodynamic and vibroacoustic processes when designing rectangular inductors. The electrodynamic calculations were done using a numerical mathematical model constructed by means of the method of coupled circuits and the principle of possible displacements.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):156-159
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Telecommunication cable efficiency performance simulation by means of the system approach
Soliakova E.O.
Abstract
The paper deals with the simulation models of performance efficiency of the telecommunication cable as a telecommunication line formed in different manufacturing processes. The performance dependence on manufacturing conditions is presented.
Vestnik of Samara State Technical University. Technical Sciences Series. 2016;24(1):160-163
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