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Urban rail planning is extremely complex, mainly because it is a decision problem under different uncertainties. In practice, travel demand is generally uncertain, and therefore, the timetabling decisions must be based on accurate estimation. This research addresses the optimization of train timetable at public transit terminals of an urban rail in a stochastic setting. To cope with stochastic fluctuation of arrival rates, a two-stage stochastic programming model is developed. The objective is to construct a daily train schedule that minimizes the expected waiting time of passengers. Due to the high computational cost of evaluating the expected value objective, the sample average approximation method is applied. The method provided statistical estimations of the optimality gap as well as lower and upper bounds and the associated confidence intervals. Numerical experiments are performed to evaluate the performance of the proposed model and the solution method. [ABSTRACT FROM AUTHOR]

The decision on how best to allocate land around transit stations is a debated topic, with transit officials often opting for park-and-ride lots over active uses such as multifamily housing, office, and retail organized into transit-oriented developments (TODs). In this study, we identify the ten best self-contained TODs in ten regions across United States based on seven criteria: dense, mixed-use, pedestrian-friendly, adjacent to transit, built after transit, fully developed, and with self-contained parking. We measure trip and parking generation at one of these TODs, the Redmond TOD in the Seattle region, as a pilot study, using an onsite count and intercept survey. The results show that the Redmond TOD has 1.7 times more trips made by walking and 3 times more trips made by transit than Seattle's regional average. The actual vehicle trips we observed are only 37 % of the Institute of Transportation Engineers' (ITE) expected value. The actual residential peak period parking demand is only 65 % of the ITE's peak demand, and the actual commercial peak period parking demand is only 27 % of the ITE's peak demand. Additionally, the peak period of transit parking was daytime, while the peak periods of commercial and residential were evening and nighttime. There is a real opportunity for sharing parking spaces among these different uses, something which is not realized at present. [ABSTRACT FROM AUTHOR]

In nearly saturated station areas the limited capacity is one of the main reasons of delay propagation. Spreading the trains well in time and space in these areas has a big impact on the passenger robustness, i.e. the total travel time in practice of all passengers in the railway network in case of frequently occurring small delays. We focus on improving the performance in the bottleneck of the network in order to improve the performance of the whole railway network. This paper proposes a method that builds from scratch a routing plan and a cyclic timetable that optimizes the infrastructure occupation and the passenger robustness. An integer linear routing model assigns, without considering a timetable, every train to a route such that the maximal node usage is minimized and that the number of times that each node is used, is quadratically penalized. Thereafter, a mixed integer linear timetabling model assigns to each train the blocking times at which the nodes on its route, assigned by the routing model, are reserved and released. Different from other approaches is that we focus on the occupation of the railway infrastructure before constructing the timetable. The approach is validated on the complex railway station area of Brussels (Belgium). Our routing plan and timetable from scratch improve the passenger robustness up to 11% compared to a reference timetable and routing plan composed by the Belgian railway infrastructure manager Infrabel and by up to 2% compared to a reference timetable and routing plan from literature. [ABSTRACT FROM AUTHOR]

An extensive air quality campaign was performed at differently designed station platforms in the Barcelona metro system, aiming to investigate the factors governing airborne particle number (N) concentrations and their size distributions. The study of the daily trends of N concentrations by different size ranges shows that concentrations of N 0.3–10 are closely related with the schedule of the metro service. Conversely, the hourly variation of N 0.007–10 (mainly composed of ultrafine particles) could be partly governed by the entrance of particles from outdoor emissions through mechanical ventilation. Measurements under different ventilation settings at three metro platforms reveal that the effect on air quality linked to changes in the tunnel ventilation depends on the station design. Night-time maintenance works in tunnels are frequent activities in the metro system; and after intense prolonged works, these can result in higher N concentrations at platforms during the following metro operating hours (by up to 30%), this being especially evident for N 1–10 . Due to the complex mixture of factors controlling N, together with the differences in trends recorded for particles within different size ranges, developing an air quality strategy at metro systems is a great challenge. When compared to street-level urban particles concentrations, the priority in metro air quality should be dealing with particles coarser than 0.3 μm. In fact, the results suggest that at narrow platforms served by single-track tunnels the current forced tunnel ventilation during operating hours is less efficient in reducing coarse particles compared to fine. [ABSTRACT FROM AUTHOR]

The train operational plan (TOP) plays a crucial role in the efficient and effective operation of an urban rail system. We optimize the train operational plan in a special network layout, an urban rail corridor with one terminal yard, by decomposing it into two sub-problems, i.e., the train departure profile optimization and the rolling stock circulation optimization. The first sub-problem synthetically optimizes frequency setting, timetabling and the rolling stock circulation at the terminal without a yard. The maximum headway function is generated to ensure the service of the train operational plan without considering travel demand, then we present a model to minimize the number of train trips, and design a heuristic algorithm to maximize the train headway. On the basis of a given timetable, the rolling stock circulation optimization only involves the terminal with a yard. We propose a model to minimize the number of trains and yard–station runs, and an algorithm to find the optimal assignment of train-trip pair connections is designed. The computational complexities of the two algorithms are both linear. Finally, a real case study shows that the train operational plan developed by our approach enables a better match of train headway and travel demand, and reduces the operational cost while satisfying the requirement of the level of service. [ABSTRACT FROM AUTHOR]

The article presents the research results of economic feasibility of trains' breaking-up order control at marshalling yards. The article objective was to determine the area of rational use of trains' breaking-up order model, formalized in the form of stochastic programming problem. As a effectiveness criterion of trains' breaking-up order operating costs of marshalling yard were used, including the costs associated with cars' and locomotives' dwell time on the station and its approaches, as well as costs associated with additional shunting work. With the help of simulation modeling the dependence was obtained, describing the impact of trains' arrival forecasting error and processed car volumes on reducing operating costs of the marshalling yards through the trains' breaking-up order control. The studies enable us to establish the requirements for the accuracy of information support of operational planning tasks, which is necessary to achieve the desired economic effect of the trains' breaking-up order control. [ABSTRACT FROM AUTHOR]

The article discusses about railway alignment at Majuba hill, South Africa, and also highlights construction of railroads.

The simulation software represents progressive contemporary experimental technique, which can support complex processes of infrastructure planning and all of activities on it. It means that simulation experiments, reflecting various planned infrastructure variants, investigate and verify their eligibilities in relation with corresponding expected operation. The paper presents special simulation software made for Department of Railway Transport by Simcon Company for simulation infrastructural layout and technological activities of complex transport centre – marshalling yard, intermodal terminal, warehouse and relations between them. [ABSTRACT FROM AUTHOR]

The application of Lean principles to terminus operations of high-speed railways has the potential of enhancing the efficiency of resource usage during both the construction and operation periods, through faster turnarounds and, hence, a reduced space requirement thanks to fewer platform tracks being needed. However, this greater efficiency must not be allowed to result in less robust services. The robust design of products and processes has been studied extensively in the manufacturing industry. By contrast, the robustness of high level railway operational concepts and system design has been investigated rarely. In this study, Taguchi methods that originated in the manufacturing industry are applied to a robustness assessment of system designs in the context of railway operations. The approach is used to assess terminus designs with different numbers of platform tracks, layouts with particular conflict patterns, minimum required turnaround times and signalling facility capability. The authors use a Monte-Carlo simulation with statistical delay distributions. The simulation results show that the signalling system's capability is the most important factor in achieving high capacity and that the robustness of railway terminus operations is not affected by adopting faster turnaround and having fewer platform tracks at termini. Finally, some suggestions for future planning are presented. [ABSTRACT FROM AUTHOR]

In this paper the train load planning problem arising in a seaport container terminal is considered. This problem consists in determining the optimal assignment of containers to wagon slots in order to maximize the train utilization and, at the same time, to minimize unproductive operations in the terminal. Different solution approaches based on a mathematical programming model are compared. The best solution procedure, satisfactory both in terms of quality of the obtained solutions and for the computational times, is identified through extensive experimental tests. This procedure could be included in a planning tool to be used in real seaport terminals. [ABSTRACT FROM AUTHOR]

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People always say that the customer is god, but do they really understand this "god"? In practice, the nature of service, such as its intangibility and heterogeneity, makes the effective management of service operations difficult. To better incorporate human behaviors and other complex factors to facilitate service management decisions, the authors propose a new approach called parallel service management. PSM, which follows the ACP framework, is an emerging methodology in complex systems modeling and analysis. In PSM, customer agents, service employee agents, service organization agents, and the service environment construct an artificial service system, which can run in parallel with the real service system. The authors developed an agent-based artificial service system for the Chengdu East Railway Station, which let them make better layout planning decisions. The modification plan was then implemented in the station and achieved significant increase in store entering rate. Statistical comparison proves PSM's potential to enhance the performance of the real service systems. [ABSTRACT FROM PUBLISHER]

The current paper focuses its study on the Southeast Europe (SEE) and tries to identify real passenger needs (demand) which can reveal rail dynamic and competitiveness in specific connections. Based on a dedicated examination of 11 SEE city hubs (Bologna, Venice, Trieste, Ljubljana, Vienna, Bratislava, Budapest, Thessaloniki, Sofia, Zagreb and Bucharest) examined within "Rail4SEE -- Rail Hub Cities for South East Europe" project, the paper aims to conclude in a quantitative analysis of demand data at regional and transnational level and on a comparative analysis based both on demand and supply data that will open the ground for the development of an accurate SEE modal split model. [ABSTRACT FROM AUTHOR]