A Decision Support System for Railway Transport

In thesis work, a cloud-based Decision Support System (DSS) is proposed to provide guidance on the level of safety and technical performance of the railway transportation systems. The DSS architecture is composed of the following modules: i) a DATABASE module containing static about the railways infrastructure and dynamic data coming in real-time from the operators; ii) the Safety and Maintenance Evaluator (SME) module containing the logical-mathematical models for the calculation of the Safety Performance Index and Technical Performance Index of the railway infrastructure, calculated using the Analytic Hierarchy Process (AHP) methodology; iii) a module named Planning Data Manager devoted to the management of the data and feed information to the SME; iv) a user interface that allows the administrator to view the data available from the data base and the indices provided by the SME. The defined performance indices are designed and computed by considering all the aspects related to the operational safety and the characteristics of the railway infrastructure defined in the specific directives, standards, regulations where the role of the human and technological components that influence the railway system are singled out. In particular, the Safety Performance Index provides to the decision maker the information on the global safety level of the railway system. The proposed index is aimed at monitoring the level of safety before the incidental event occurs. The introduced innovation is related to the use of data relating to accident precursors. The safety performance index allows defining the level of security with respect to the railway infrastructure and train fleet. The value of the index allows the decision maker to define the corrective actions to be taken to bring the level of risk back to an acceptable level. Moreover, the Technical Performance Index of the railway infrastructure provides guidance on the availability of the railway infrastructure. This index is a measure of the failure incidences in the components of a railway system. The methodology results give information on the availability of the railway service and can positively influence the decision of the railway manager infrastructure in terms of financial investments ad reorganization of maintenance. The two indices are determined by applying the AHP methodology in order to derive tabulated weights and evaluate the safety performance level of the train transportation system by considering the contribution of every single failure in the human safety impact. The main advantages introduced by the DSS presented in the thesis are the following: i) the possibility of increasing the safety level of the railway transport system by allowing the decision makers to monitor in real-time the system and to promptly implement actions to mitigate and reduce the risk level; ii) the possibility of improving the quality and regularity of the services by minimizing the unavailability of the railway infrastructure for causes related to breakdowns and malfunctions of the equipment; iii) allowing the workers to optimize maintenance activities by properly planning and defining extraordinary maintenance interventions allocating human and economic resources appropriately.