Functional analysis of the sub-system of energy and infrastructure of conventional rail

The paper deals with the functional analysis used to classify and to determine the functions and safety requirements of a complex system. In the functional analysis, the solution for the targeted problem is modelled and decomposed into finer granularity in order to identify all functions, interfaces and requirements. The proposed approach is based on the functional decomposition and the safety analysis and proof to allow systems requirements capture, analysis and validation. The consistency of system requirements and their relation are validated by a formal proof technique. The functional analyses based on functional decomposition and requirements proof have been conducted to analyse the European Conventional Railways System specification. The approach is illustrated by a sub-system of conventional rail to analyze the constituents and the essential requirements needed to achieve interoperability within the trans-European rail system.