Derivation of the safety function through safety analysis procedure in the train operation system

초록

The safety of the railway system is important because the railway system is a mass transit system and the result of the accident is inconceivable. The railway system is operated by train operation system such as train control system. So the train control system is a safety critical system. Recently, urban railway system is operated by driverless and automatic train control system. More safety is required than before in the railway system. In order to accomplish the safety of a system, functions for safety have to be derived. The functions are deduced by safety analysis. In order to perform the safety analysis, the system hazards have to be identified and then risk analysis for each hazard should be performed. The risk is related to the frequency and the severity of each hazard. And then countermeasures for each risk have to be prepared. The summary of the countermeasures is about a kind of safety functions in a system. In this paper, the safety functions for a train operation system are presented according to the above procedure.