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Is executed the analysis of the permissible range of the fluctuation of the phase of signal on the entrance of digital measuring device with a study of phase relationships in the tractive networks of the power supply of rail transport, characterized by high noise level.

The article describes a software module of the initial image processing which allows to perform the contour image analysis in order to find, recognize and evaluate graphic images of various types of inhomogeneities. Application of software module will improve the accuracy of the evaluation of the internal surface of closed vessels in the absence of access control.

The quality of a track circuit monitoring system is defined to the great extent by its ability to automatically analyse the acquired data, i. e. identify the state of a track circuit. Machine learning techniques can be applied to implement this functionality. Designing a machine learning algorithm requires a learning data set from the subject domain. In this article we discuss a basic principle of track circuit mathematical model design that could be used to generate such data set. We also apply this principle and a combination of some existing methods to design and demonstrate a mathematical model of the 25 Hz AC track circuit.

The article describes three variants of the mathematical model of the sensitivity function of the magnetoinduction sensor for assessing the influence of various sensor parameters in the electromechanical system «wheel - rail - magnetoinduction sensor» for diagnosing the technical condition of the rolling surface of the rolling wheels of rolling stock in the process of its movement over the sensor. An example of an algorithm for identifying defects located on the surface of the wheel rolling circle is described. The proposed multi-vector mathematical model allows simulating various defects on the rolling surface of the wheel, developing and testing new algorithms for processing the output signal of the sensor on the basis of modern hardware and software. The implemented defect identification algorithm is based on the property of the centrally symmetric form of the sensitivity function of the magnetoinduction sensor and the allocation of a useful signal corresponding to a certain type of defect, based on the application of a mutual correlation function and the assessment of its maximum and minimum values in comparison with the specified thresholds and confidence intervals. The main requirement for the implementation of the model is the uniform movement of the train above the sensor along a straight section of the rail track. This article discusses only one of the possible digital signal processing algorithms, but the proposed model allows us to compare the efficiency of other possible algorithms identification of defects in the rolling surface of wheelsets. The developed model confirms the prospects of using magnetic induction sensors for identification of not only visible, but also hidden defects on the rolling surface of the wheel in the process of movement of the train.

In the work completed a study of shape vertices a unimodel probability density function (kurtosis) on the output of the nonlinear converter «phase shift - code, which is the most important parameter for evaluating conditions of finding mode to this function. To increase the accuracy of assessment shifts phases when there is high level of random noise is defined not only quality, but also quantitative dependence of the kurtosis probability density function on the output of the nonlinear converter «phase shift - code» of Standard deviation phase fluctuations of the signal at its input. The mathematical model of the distribution function on the output of the converter «phase shift - code» for research and implementation of algorithms improve noise immunity measure phase shifts between harmonic components of voltage and current in traction power supply rail transport networks.

In work done modeling and analysis of noise immunity of the proposed measurement method of phase shifts between harmonic components of voltage and current in traction power supply rail transport networks and estimation of maximum permissible noise level, where workability digital devices used to study phase shifts in these conditions. The simulation results have shown that the probability density function on the output of the nonlinear converter «phase shift - code» remains a unimode at any ratio range converter and standard deviation of the phase of the input signal. Implementation of researched ways of microprocessor-based digital device guarantees the stability and accuracy of measurement results in traction phase shifting networks of power supply of railway transport in the presence of high levels of industrial noise, nonlinear fast variable nature of the traction load, sparking the pantographs for electric locomotives in contact network and use recovery systems based on pulse converters.

The analysis of electric energy quality with a required by modern standards accuracy demands applying of digital signals processing. At measurement, one of the main operations is finding signals correlation. Operations performance over digital representations of the signals containing a large points number requires many of computing resources that results in importance of a fast correlation calculation problem. The well-known methods of correlation calculation is applying a range of algorithms: transformation correlation to cyclic convolution, calculation cyclic convolution through FFT and others. These algorithms are well-studied, however their combination make possible additional optimization of algorithms. In paper we offer the method of computing procedure optimization for signals correlation calculation based on operations reduction when performing a sequence two Fourier transformations. Using another way of placing the calculations results we can reduce a data rearranging operations number. Depending on computing architecture, the offered method allows to accelerate calculations to 20 - 25%.

The method of an estimation of reliability of functioning and probability of conditional non-failure operation of a network element telecommunication in view of factor of availability is considered

The article presents a nonlinear mathematical model of heating a two-layer body with allowance of the finite velocity of heat propagation and the temperature dependence of the properties of materials. A numerical solution of the nonlinear hyperbolic heat conduction problem is obtained for the case when the absorption of the radiation energy is modeled by a volumetric heat source. The implementation of the grid method using a three-layer implicit difference scheme in solving a nonlinear heat conduction problem in a two-layer body with allowance for the relaxation of the heat flux and the conjugation conditions in the case of ideal contact at the interface junction is considered. The described algorithm for calculating the temperature field for high-intensity heating of a coated body, taking into account the dependence of the thermophysical characteristics of materials from temperature, is based on the implementation of the sweep method with iterative correction of the coefficients. Programs are developed and the results of calculating the temperature fields are presented using nonlinear hyperbolic heat conduction equations and the corresponding linear ones taking into account the average integrated thermal and optical characteristics of the materials. Based on a comparison of the results obtained the necessity of taking into account the temperature dependence of the properties of materials during the study of processes of high-intensity heating of bodies.The developed mathematical model on the basis of a system of nonlinear hyperbolic equations can be used to create technological processes using methods for processing the surface of multilayer bodies by laser radiation.

We consider the ways of increasing the effectiveness of the information-measuring complex of an automated system for monitoring and metering electricity. The possibility of reducing the volume of telemetry traffic in information transmission channels and increasing the energy efficiency of information-measuring equipment is investigated.

The paper deals with the problem of the presence of thermal inertia in thermoelectric converters of general industrial design, used to measure temperature in most technological installations with an ambient temperature above 200 ° C. The aim of the study is to develop an algorithm for predicting the temperature of the environment with known thermal characteristics of the temperature sensor and to implement the algorithm directly in a general industrial programmable logic controller (PLC). As the main method, the work uses the method of mathematical modeling and description of the object in transfer functions and in the form of differential equations. The work uses a previously developed engineering technique for determining the thermal inertia time of industrial sensors, based on a single disturbance and an assessment of the dynamic characteristics of an object. On the basis of the research and mathematical modeling, algorithms for predicting the temperature of the medium by the parameters of the thermal inertia of the temperature sensor and the rate of change of the thermocouple signal have been developed and implemented. The implementation of the algorithms in the TIA Portal environment based on the Siemens Simatic S7-300 PLC using the PID Control library is proposed.

In this article, a scientific approach to optimizing the electromechanical route for servicing the centralization and blocking devices at the station is considered. For this purpose, the authors propose to use the algorithm for solving the known traveling salesman problem. This algorithm is the basis for constructing technological maps of the movement of electromechanics around the station, as a component of technological maintenance cards for automation and telemechanics devices.

The problem of optimizing train driving modes continues to be relevant for a long time, despite a large number of scientific research and development in this subject area. This is due both to the general complexity of the implementation of the technological process of running the train, and to parametric uncertainty and significant variations in the parameters of the control object itself and the external environment. Well-known methods for calculating energy-optimal train driving modes (calculus of variations, the maximum principle, dynamic programming) and auto-driving systems based on them assume some simplifications of the original problem, and, as a result, implement quasi-optimal control in practice. In this regard, the development of methods for searching for the global extremum of a functional defined on the set of permissible trajectories of a train as a dynamic system is both theoretically and practically a significant task. The aim of the work is to create a computationally efficient metaheuristic algorithm for searching for energy-optimal control as a global extremum of the objective function, the values of which are calculated using a reference model of the control object. The authors have developed a problem-oriented evolutionary algorithm for calculating the optimal control of train movement based on the theory of random search. Its features are the proposed specialized operators of local random search, taking into account the specifics of the control object as a multi-mode system; combined procedures of local and global optimization based on the concept of a multi-island population algorithm with superpopulation, as well as a method of selection (selection) of promising options based on the clustering algorithm. Computational experiments have shown good convergence of the algorithm and repeatability of the calculation results. Based on the solutions obtained, a train running time controller can be implemented that implements asymptotically optimal control.

The article is devoted to numerical methods for solving nonlinear heat conduction problems with considering for the relaxation of heat flow. A mathematical model is developed on the basis of a non-linear heat equation of the hyperbolic type for calculating the temperature field in an infinitely extended (unlimited) plate. The implementation of the grid method using a three-layer implicit difference scheme for solving the nonlinear hyperbolic heat conduction problem is presented for the case when the absorption of radiation energy is modeled by a volumetric heat source. A numerical solution of the nonlinear heat conduction problem in an unbounded plate is obtained taking into account the relaxation of the heat flow on the basis of the finite difference technique using the sweep method and iterative refinement of the coefficients. A calculation algorithm with a graphical representation of the results of calculating the temperature field in an unbounded plate under the influence of concentrated energy flows is described. A comparison of the results of calculations of temperature fields in mathematical modeling on the basis of the nonlinear hyperbolic heat equation and the corresponding linear model using the mean integral values of thermophysical and optical characteristics is presented. The significant differences obtained between the temperature fields corresponding to the nonlinear and linear problems justify the need to take into account the temperature dependence of the thermophysical characteristics and the absorptivity in the study of high-intensity processes of heating the bodies. The developed nonlinear mathematical model of body heating with allowance for the finite speed of heat distribution and the temperature dependence of the material properties, can be used to select the modes for processing mode bodies with high-intensity energy flows.

We propose the concept of the new system for monitoring and electricity metering on the feeders of the D.C. contact network. The system is based on previously designed prototype that has been put into operation, and differs from it in new solutions that allow to achieve greater mobility and simple scalability. We describe the basic technical solutions, the system functions as well as its potential.

To improve the accuracy of the diagnosis of the technical condition of rolling stock, it is necessary to develop new algorithms for the digital processing of signals coming from sensors at the time of the passage of the axes of wheeled pairs of wagon carts during the uniform movement of the train on the straight section of the railway track. The use of modern mathematical application software packages to model digital-based data processing algorithms reduces the cost and time of developing automated systems to diagnose the technical condition of the rolling stock of railways. To assess the accuracy of the fixation by the magneto-induction sensor of the moment of passage of wheel pairs axly, an asthigmatic model is proposed, allowing to investigate not only the energy properties of the sensor, but also the shape of the output signal, taking into account the real dimensions of its magnetic core. The developed model allows you to classify the pore. The developed model allows to classify the order of astigmatism model magnetoinduction sensor based on a set of discrete virtual sensors

Railway telecommunications are inherent facilities participating in the organization of efficient and safe transport process. Generally, reliable operation of telecommunication devices is provided by the implementation of preventive maintenance that quality analysis is performed on the incidents during the latest reporting period. The possibility of experimental estimation using computer techniques surely has advantages. In the paper, we have defined an objective of the development of a simulation model of the operation process of railway telecommunications so as to assess the inherent availability and maintenance quality indicator. The model allows carrying out a computer experiment and estimation of the abovementioned measures in an automated way taking into account the following input parameters: failure rates, periodicity and length of maintenance, time of repair, the probability of erroneous actions of service staff and the probability of spare and replacement parts lack.

The article discusses the operation of systems for interval regulation of train traffic based on a digital radio channel in the absence of radio communication. The aim of the study is to determine the maximum allowable time for the absence of radio communication between the radio blocking center and a moving train in the interval control system. Criteria are proposed that allow assessing traffic safety, as well as reducing the throughput of train traffic in interval control of train traffic systems. The results of calculating the maximum permissible time of radio communication absence in interval control of train traffic systems for freight trains are obtained. Taking into account the maximum allowable time for the absence of radio communication will completely eliminate the likelihood of a dangerous convergence of trains and ensure compliance with the allowable speed mode with a minimum interval of freight trains.

We consider the concept and architectural aspects of the development of the corporate information sys-tem for monitoring and resources accounting. The relevance of improving automated systems is due to the intensification of the use of modern information technologies in industry. The aim of the work is to select the architecture of the distributed information system for monitoring and resources accounting (hereinafter - the system), which ensures prompt decision-making in the management of technological objects. We consider the current trends in the development of information systems and concepts that provide the requirements established for systems of this class and purpose. The system is based on previously designed prototype that has been put into operation, and differs from it in new solutions that allow to increase mobility and fault tolerance. We describe the basic implemented architectures and the system functionality.

The article presents the results of research of a point magneto-induction sensor based on a mathematical model, which allows you to increase the reliability of automated systems for diagnosing technical condition rolling stock in the course of train movement by improvement the accuracy of the initial information, that is, the moments of fixation passing of wheelset axles over magneto-induction sensors. At the first stage of developing a stigmatic mathematical model the analytical dependence of the value of the magnetic flux in the magnetic core and the output EMF value on resistance of the air gap between the sensor and the wheel crest. At the second stage of development of the mathematical model found time dependence of the magnetic resistance of the air gap between the core of the magneto-induction sensor and the comb wheels of a railway car moving along a straight track at a constant speed. On the basis of application the developed stigmatic model allows evaluating the energy parameters of magneto-induction sensors depending on the properties of modern magnetic materials. The simulation results showed that the MMF value is constant the magnet determines the main parameters of magneto-induction sensors, so the use of modern magnets based on rare earth they allow to eliminate the traditional disadvantage of outdated types of magneto-induction sensors, that is, to reduce their size and weight. The application of the proposed stigmatic model expands the scope of possible solutions to extreme problems for selection and justification parameters of magneto-induction sensors, helps to improve the accuracy of systems for diagnosing the technical condition of the car fleet and traffic safety on railway transport.

Developed Methodology let make the calculation of coaxial cable parameters with account of the frequency of the transmitted signal. The comparative analysis of parameters of RC 50-7-28 and RG142 cables has been made with the values have been got by the measuring with the circuit analyzer according to the reference book with the results of the calculations. Check the accuracy of the calculation has pointed out the necessity for account of complementary factors for the purpose of much more correct account cable attenuation in the frequency spectrum.

The authors consider the question of the limits of applicability of the capacitor method for measuring the real part of the dielectric constant of printed circuit boards and telecommunications cabled rail transport using the example of FR-4 fiberglass laminate and the cable PK-75-4-12 in the frequency range from 10 Hz to 100 MHz. The measurements were carried out at a constant temperature and humidity of a known material. Comparison of the obtained values with the passport data on the material is carried out; a measurement procedure is developed with overlapping frequency ranges by changing the values of the measuring resistors from larger to smaller with increasing frequency of the input signal. It is shown that in the high-frequency region, the measurement accuracy is directly affected by the parasitic inductance of the capacitor sample under study, as well as the active resistance of the leads and plates and its increase due to the skin effect. The article also discusses the ways of accounting and calculating the parasitic elements of a capacitor. One of these ways is to study the characteristics of the elements of the sample at the first proper serial resonance of the capacitor under study.

The paper considers the use of simulation modeling in the reengineering of technological processes for repairing rolling stock units on the example of repairing a bogie model 18-578 of an open-top car. The most time-consuming sub-process of repairing the bolster of this bogie was considered as the object of reengineering. Three options for reengineering of this subprocess were considered, implying a complete replacement of the technological equipment currently in use at repair operations (positions) with more efficient positions of the subprocess. To substantiate the choice of the most preferable reengineering option, the values of such indicators of the functioning of the subprocess under consideration as its productivity per shift (throughput), the load factor of the resources used at the repair positions, the volume of work in progress at the end of the shift, the number of workers employed in production and the costs associated with the possible purchase of new technological equipment. Simulation modeling of the functioning of the considered sub-process of bogie bolster repair was carried out on the basis of the methods of the queuing theory. The construction of simulation models and their assessment of the above indicators were carried out in the Arena RockWell Software environment. When developing simulation models for each of the possible options for reengineering a subprocess, the discipline of its organization and maintenance was taken into account. In the article, for each of the reengineering options, the calculated quantitative estimates of the listed indicators are presented, obtained using the corresponding developed simulation models. The use of these assessments reduces the risks in the development and subsequent implementation of organizational and technical solutions associated with the modernization of the considered technological sub-process of repair of the bolster of a gondola car bogie.

Microminiaturization elements of communication systems contributed to development Internet of Things, which led the expansion of various railway transport services. One of the Internet of Things component`s is the wireless sensor network (WSN). Feature of WSN is a dynamically changing spatial and information network environment. It complicates the adoption of promptly reliable management decisions based on assessments of the states of network elements. One of the directions of making a reliable decision in a complex network environment on the WSN is using cognitive maps in the WSN control nodes. In this article discusses various models of cognitive maps for assessing the states of network elements and network processes, which can also be used for railway transport services.

The article is devoted to the features of the implementation of the user interface of an automated information system for processing and analyzing data about the energy consumption of locomotives, ensuring its effective functioning in order to improve the control of fuel and energy resources consumption for train traction.