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Electrified railway systems are the current focus of energy efficiency studies due to the increasing constraints of environmental sustainability policies. Railway System Operators (RSOs), also encouraged by market deregulation, are thus examining how to update infrastructures and vehicles and/or apply new operating strategies. Given the intrinsic relation between railway systems and their primary feeding grid, each measure applied to a railway system impacts directly on the power grid which supplies the system. Against this background, this paper aims to ascertain the impact of an energy efficiency strategy applied by the RSO system on its primary grid. The energy-efficient strategy is identified as to preserve timetable stability and service quality in a passenger-oriented perspective. Moreover, a method to model the interaction between the systems in terms of power flow exchanges is proposed. The model is used to verify how an eco-driving technique applied to a metro system affects the state variables of the distribution grid. In particular, the primary grid, the traction power substations and the railway system are modelled according to real data. The case study is the Metro Line 1 operating in the city of Naples (Italy). The numerical simulations are carried out with a two-step procedure: first, the power requirements of the rolling stock as a function of the imposed operating service are calculated by OpenTrack® software; the state variables of the distribution grid are then evaluated by means of the power flow approach. [ABSTRACT FROM AUTHOR]

Forecasting user flows on transportation networks is a fundamental task for Intelligent Transport Systems (ITSs). Indeed, most control and management strategies on transportation systems are based on the knowledge of user flows. For implementing ITS strategies, the forecast of user flows on some network links obtained as a function of user flows on other links (for instance, where data are available in real time with sensors) may provide a significant contribution. In this paper, we propose the use of Artificial Neural Networks (ANNs) for forecasting metro onboard passenger flows as a function of passenger counts at station turnstiles. We assume that metro station turnstiles record the number of passengers entering by means of an automatic counting system and that these data are available every few minutes (temporal aggregation); the objective is to estimate onboard passengers on each track section of the line (i.e., between two successive stations) as a function of turnstile data collected in the previous periods. The choice of the period length may depend on service schedules. Artificial Neural Networks are trained by using simulation data obtained with a dynamic loading procedure of the rail line. The proposed approach is tested on a real-scale case: Line 1 of the Naples metro system (Italy). Numerical results show that the proposed approach is able to forecast the flows on metro sections with satisfactory precision. [ABSTRACT FROM AUTHOR]

Since 1839, when the historical railway Naples - Portici was inaugurated, Naples has been characterized by a significant system of urban and suburban railways. The idea of a fully integrated urban rail network dates back to the 1950s, but construction only began in the 1990s. At present, the system includes 54 km of tracks and 69 stations in operation; ten lines with 93 km of track and a further 30 km of new light rail linking 114 stations with 21 interchanges are planned with the completion of the City Transport Plan. The present paper reports on some geotechnical aspects of the design and construction of Lines 1 and 6, which are presently underway, discussing how the experience gathered during construction of Line 1 influenced some of the design choices for Line 6. Seit 1839, als die historische Eisenbahnstrecke Neapel - Portici eröffnet wurde, wurde Neapel durch sein umfangreiches Schienennetz im städtischen und vorstädtischen Bereich bekannt. Die Idee eines vollständig integrierten Bahnnetzes geht in die 1950er Jahre zurück, der Bau wurde jedoch erst in den 1990er Jahren aufgenommen. Derzeit umfasst das Netz 54 km Schiene und 69 Stationen; mit Vollendung des städtischen Verkehrsplans sind zehn Linien mit 93 km Schiene sowie weitere 30 km einer neuen Stadtbahn, die 114 Stationen und 21 Knotenpunkte verbindet, geplant. Dieser Artikel beschreibt einige geotechnische Aspekte hinsichtlich Planung und Ausführung der sich derzeit im Bau befindlichen Linien 1 und 6, wobei erläutert wird, wie die beim Bau der Linie 1 gesammelten Erfahrungswerte einige Planungsentscheidungen der Linie 6 beeinflusst haben. [ABSTRACT FROM AUTHOR]