Springer Science and Business Media LLC

Media reports on train mishaps and havocs emanating from rooftop riding abound; however, there has been very limited effort on the empirical investigation of why daredevils embark on this utter suicide mission. Besides, studies that rigorously examined profiles of the perpetrators of the dastardly act are hard to come by in the literature of railway transport. Against this background, this study examined the menace of train rooftop riding in Lagos Metropolis, Nigeria, with a view to evolving a policy response that could curtail the life-threatening nuisance. Towards achieving this aim, specific objectives were formulated. These were to examine the socioeconomic characteristics of train rooftop riders in Lagos Metropolis, determine the motivations for train rooftop riding in the study area, assess the efforts made by the authorities to discourage train rooftop riding in the study area, and proffer policy recommendations towards engendering a safe rail transport milieu. Data were obtained through participant observation, interview and questionnaire administration. The respondents comprised 64 conveniently sampled rooftop riders, 183 law-abiding passengers of three Diesel Multiple Units and three Mass Transit Trains selected using multistage sampling, and the 113 staff members of the Nigerian Railway Corporation consisting of 20 engineers, 79 conductors and 14 ticket vendors. The study found that train rooftop riding had defied all the measures taken against it in the study area. It characterized most trips but was prevalent at the morning and evening peak periods (35.2% and 59.2%, respectively). All the rooftop riders were middle-aged men. None of them admitted to ever falling off before; however, 28 (43.8%) admitted to being scared of falling off, while 40 (62.5%) boasted they could not possibly fall off. Two categories of motivations for rooftop riding were found: ‘perceived’ and ‘real’. Smoking (47.0%), substance abuse (23.0%) and criminal tendencies (19.7%) were among the perceived motivations, while space inadequacy (37.5%), queue avoidance (50.0%) and adventure (34.4%) were among the real motivations. Given an overall improvement in the railway services, 28 (43.8%) would stop, 18 (28.1%) would not stop, and 18 (28.1%) were unsure they would stop rooftop riding. The study concluded that the menace of train rooftop riding was undesirable. Consequently, practical policy recommendations were proffered towards curbing the menace.

Urban rail transit connecting with a comprehensive transportation hub should meet passenger demands not only within the urban area, but also from outer areas through high-speed railways or planes, which leads to different characteristics of passenger demands. This paper discusses two strategies to deal with these complex passenger demands from two aspects: transit train formation and real-time holding control. First, we establish a model to optimize the multi-marshalling problem by minimizing the trains’ vacant capacities to cope with the fluctuation of demand in different periods. Then, we establish another model to control the multi-marshalling trains in real time to minimize the passengers’ total waiting time. A genetic algorithm (GA) is designed to solve the integrated two-step model of optimizing the number, timetable and real-time holding control of the multi-marshalling trains. The numerical results show that the combined two-step model of multi-marshalling operation and holding control at stations can better deal with the demand fluctuation of urban rail transit connecting with the comprehensive transportation hub. This method can efficiently reduce the number of passengers detained at the hub station as well as the waiting time without increasing the passengers’ on-train time even with highly fluctuating passenger flow.

It is important to strengthen the research on urban rail transit (URT) existing line renovation strategies. In this paper, we investigate the optimization of bottlenecks that are less attractive but have strong travel demand in existing URT networks. A URT local line optimization model is constructed. The maximum passenger flow and minimum project cost are chosen as the optimization objective for the benefit of both passengers and operators, and several actual constraints are considered in the proposed model, such as the station interval. In order to obtain higher computational efficiency and accuracy, a passenger flow allocation method is embedded in a genetic algorithm with elitist preservation. Taking the local network of the Beijing URT as a case study, the calculation results show that the designed algorithm can quickly and effectively obtain the optimal solution, and the generated local line scheme is able not only to meet the regional travel demand, but also to optimize the connection relationship of the existing URT network. This study can provide a reference method for increasing the attraction of URT and optimization of existing URT networks.