A formalized scheme of a railway line simulation model was demonstrated on the basis of continuous signal discrete approximation; the former being the key component of the intelligent database of the hybrid expert system for audio frequency track circuit performance analysis. A discrete model of continuous input signal was presented, as well as the analytic expression of its transformation by the selected items of the railway track given in the form of array-based pointwise values of an approximated signal. It was suggested to divide the railway line into segments, presented in the simulation model by equivalent circuits. The latter provided adequacy of shunt and control operation modes of the track circuit. The influence of adjacent and neighboring railway circuits of continuous welded rail track was taken into consideration in the formalized scheme on reflective and algorithmic levels. The mathematical scheme made it possible to use the method of process modeling for synthesis of a continuous signal processing simulation model in the railway line. Analytic expressions were introduced for accounting purposes of interfering factors in order to provide adequacy of the process simulation model, in the formalized scheme of the railway line. A multitude of operators and logical conditions of alphabet of logical algorithm schemes were introduced on the basis of analytic expressions introduced in the article. A formalized description of the railway line operation in different modes (normal, shunt, control, automatic train control and short-circuit) was developed using the introduced alphabet based on the language of logical algorithm schemes. It provides relative simplicity of transition to software implementation of the railway line process simulation model for continuous welded rails.
Process modeling, audio frequency track circuit, railway line, equivalent circuit, formalized description, hybrid expert system