A methodology for assessing the feasibility of fleet compositions with dynamic demand

In the last twenty years, European Union has promoted liberalisation and competition within the rail system under EC Directive 91/440 and the Railway Packages concerned, and all Member States now try to pursue the difficult task of considering both public (sustainability, accessibility, employment, etc.) and commercial interests (profit, return on investment, growth). In this context, it is necessary to carry out analyses about rail services so as to gain useful information for increasing efficiency, effectiveness and productivity. In many cases, great importance has been attached to Key Performance Indicators (KPIs) which do not usually consider customer needs. This paper aims to promote a Decision Support System (DSS) for assessing rail services taking both service quality and performance indexes into account. In particular, the procedure is based on a microscopic simulation model combined to an assignment tool for assigning dynamically passengers to services. Thus, demand peaks, temporary capacity variations, temporary over-saturation of supply elements, and formation and dispersion of queues can be considered providing a more precise analysis of rail services. An application on metro Line 1 in Naples (Italy) is presented in order to explain the workings of the model. Numerical results demonstrate that this approach is very useful for planning or managing rail systems in accordance with passenger satisfaction and operational efficiency.