Method of determining time for preventive diagnosis in city bus operation systems

The article presents a mathematical model of the process of diagnosing and repairing preventive public transport buses. The mathematical model was developed using the theory of semi-Markov processes. The presented model considers two types of corrective repairs - carried out by the Technical Emergency Service and at Service Stations, and preventive repair. The presented model of the exploitation process system has been described to a small extent in the literature so far. The considered system is analyzed on the basis of two criteria: the availability of public transport buses and the profit per unit time. For the adopted assumptions, the conditions for the existence of an extremum of the criterion function were formulated. In the article, the presented model is illustrated based on sample results.