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Introduction. The problem of determining the train coordinates on the approach section to the crossing is associated with the impact of destabilizing factors on the information primary detector ? the rail line with distributed parameters. This leads to an error in calculating train coordinates. The aim of the study is to develop and scientifically substantiate the principle of building a system for calculating train coordinates with self-tuning of the decision function under the influence of significant destabilizing factors on the information primary sensor. Materials and Methods. To solve the problem of reliable determination of train coordinates, we propose a two-phase principle for forming the decision function. At the first stage, by means of a training sample of images and using the learning principle, the decision function (model) of the system for calculating train coordinates is determined. When the train enters a fixed-length approach section, the mismatch is determined by comparing the calculated coordinate with the fixed one. The second stage is the self-tuning of the coefficients of the decision function until the required accuracy is achieved. Results. The article shows the stages of forming the decision function by two-dimensional images; there was developed and tested an algorithm for self-turning of the decision function under the influence of various destabilizing factors. Through using 6 attributes of components of current and voltage vectors at the rail line input, 6 solving functions were obtained. Various combinations of two-dimensional images were used as polynomial arguments. Discussion and Conclusion. The study results confirm the feasibility of forming decision function and its self-tuning. The maximum error in calculating coordinates for various combinations ranges from 9.97% (199.34 m) to 4.57% (91.49 m). The error of determination of 5% for two decisive functions satisfies the safety requirements, since in a 45-second time interval to activate an automatic crossing signal, a distance of 100 m is covered in 3 seconds, i.e. the elapsed time is only 3 seconds in a 45 second interval.

This paper proposes a two-city model for investigating the effects of investing in intra-city and inter-city rail lines, in which population migration and commuting between cities may occur and the spatial structure of each city is explicitly treated. The rail lines concerned include subway line within a city and high-speed rail (HSR) line between cities. The cities in the two-city system are differentiated into high-income and low-income ones according to their average wage levels of employments. Five scenarios of rail line investments are considered: (i) constructing HSR line between cities, (ii) constructing subway line in high-income city, (iii) constructing subway line in high-income city and HSR line between cities, (iv) constructing subway line in each city, and (v) constructing subway line in each city and HSR line between cities. The rivalry between concentration and dispersion effects of subway and HSR line investments for the five scenarios are analytically explored in terms of residential location/workplace/travel mode choices, inter-city commuting, population migration, and urban spatial structure. The conditions for inducing inter-city commuting and cities' mergence due to rail line investments are identified. Numerical simulations are provided to illustrate the properties and applications of the proposed model, together with a case study of an urban agglomeration located in Central China. • Proposes a two-city model for investigating the effects of inter-city and intra-city rail line investments. • Investigate and compare five scenarios of rail line investments. • Reveal the rivalry between concentration and dispersion effects due to intra-city and inter-city rail line investments. • Identify the conditions for inducing inter-city commuting and cities' mergence due to rail line investments. • Conduct a case study of an urban agglomeration located in Central China. [ABSTRACT FROM AUTHOR]

Introduction. The time interval systems for controlling train movement operated under the influence of significant industrial disturbances, interference from the electric current of traction rolling stocks, and significant climate changes that result in fluctuations of parameters of circuit elements. These factors lead to the appearance of internal disturbances. The fluctuations in a wide range of the conductivity of rail lines insulation are the main external disturbances leading to considerable changes of the informative parameter, the voltage at the output end of the rail line. At present, there are many methods for suppressing disturbances, which allow correcting fluctuations in the informative signal without deteriorating the quality of classification. The article deals with the problem of providing insensitivity of the output informative signal to the influence of disturbance by principles of coordinate compensation with a correcting link. Materials and Methods. To solve the problem, various methodologies of compensation for disturbances are considered in the paper; the method of coordinate compensation for disturbances at the input of a quadripole of rail lines is adopted as the main one. The equation of the transfer function of the correcting link is determined, assuming an indirect measurement of the input resistance of the rail line, which is a function of the conductivity of the insulation. Results. The article presents the results of the research of the invariant capabilities of the disturbance compensation principle. It is shown that disturbances compensation with a corrective link included at the input of a quadripole allows one to significantly reduce the dynamic range of the output informative signal change in each of the classes, i.e. classes have become more compact, and the quality of classification has become 5 times higher than in the absence of compensation of disturbances. Discussion and Conclusion. The results confirm the effectiveness of the proposed method for the coordinate compensation of disturbances in rail lines with an open circuit in the absence of the possibility for organizing feedback, a variable circuit in each of the classes of states, and the impossibility of creating a physical additional channel for the transmission of the disturbance. Using the proposed method in the construction of modern classifiers will significantly improve the stability of the functioning of train control systems; eliminate errors of the first kind, leading to unproductive idle train, and errors of the second kind, leading to accidents and crashes.

This paper considers the carrier frequency selection method for continuous cab signaling using a set of criteria for minimum inductive-rail line attenuation and maximum noise immunity. The mathematical expressions used for evaluation of signal attenuation in rail, inductive, and inductive-rail lines are given, and the corresponding conditions and assumptions are indicated. To determine the locomotive receiver noise immunity, the method of simulating its operation was used when receiving an additive mixture of an amplitude-shift keyed signal and impulse noise. It is shown that, under the indicated conditions and criteria, the optimal frequency values are 325 and 375 Hz. [ABSTRACT FROM AUTHOR]

This paper offers a simulation model for analysing the utilization levels of a section of a railway line between Edinburgh Waverley and Glasgow Queen Street. Specifically, a segment of this line situated in the urban area of Edinburgh has been simulated using SIMUL8 to study the impacts of further inclusion of freight trains on the scheduled passenger trains. The utilisation levels of this segment have been observed in three scenarios: utilisation existing state where all scheduled passenger trains and a few freight trains are observed; utilisation in future state where more freight trains are input in available time gaps running at their actual speed; and utilisation future state where freight trains are input in available time gaps running at speed equivalent to a passenger train. A decomposition approach is implemented. The results suggest that extra freight trains can be input into the current timetables without impeding the current scenario, allowing a reasonable increase in utilisation of the rail line.

Purpose. The article deals with the insulation resistance of the track circuit as one of the parameters that affect the operating performance of the railway transport. To reduce the influence of the insulation resistance on the operation modes of the track circuits and the performance indicators of railway transport it is assumed to study the influence of crushed stone treatment on the value of dielectric permeability of the ballast bed. Methodology. The influence of material type for the surface treatment of crushed stone on the value of the dielectric permeability was assessed on the basis of the physical nature determination of the relative dielectric permeability. Determination of the relative dielectric permeability of granular media can only be indirect, as a consequence of incomplete adjoining of crushed stone grains and uncertainty of the pore volume. Thus, the calculations were performed by comparing the measured capacity for a medium with the known with measured medium capacity, for which it is necessary to define. That is, the more the measured capacity is changed, the more changes the dielectric permeability of the medium. Findings. Sleepers and ballast significantly change their electrical conductivity depending on the presence of moisture, ambient temperature changes, the presence of pollutants and other factors. The article analyzes the existing models to describe the dielectric properties of such systems. It has been established that coating the crushed stone ballast with organic substances influences the value of its relative dielectric permeability. The greatest effect of reducing this value is observed for the coatings based on rosin mixture and silicone. Originality. Authors proposed original method of dielectric properties increase of the permanent way by grains’ coating with nonwettable substances, on the surface of which is not formed a water film. Practical value. The article shows the possibility of minimizing the negative influence of reducing the isolation with maximum its elimination. It is proposed the solution of actual problem by eliminating the influence of insulation resistance on the modes of track circuits operation, which will eliminate the part of causes of the failure of signaling devices and reduce the number of cases of «false business».