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Passengers experience significant inconvenience from track closures required for planned maintenance and infrastructure updates of rail networks. Generally, operators restore connectivity with shuttle busses replacing the closed link in... more
Passengers experience significant inconvenience from track closures required for planned maintenance and infrastructure updates of rail networks. Generally, operators restore connectivity with shuttle busses replacing the closed link in the network. This however introduces additional transfers, while the speed of travel on busses for the replaced links is generally lower than the speed of the previous rail service. Therefore, a passenger-demand based design of shuttle services that takes into account the true origin and destination of passengers, the change in speed on the bussedlinks, and possible alternative routes for busses, may improve passenger service without increasing operating cost. This presentation will cover two topics. On the one hand, it will give a short overview of some of the work done by the authors on deducing passenger behavior from smart card data in the Netherlands. This includes the deduction of route choices and travel patterns of passengers. Furthermore, th...
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Railway operations are disrupted frequently. The disrupted situation requires to adapt the timetable and the resource schedules quickly. This research focuses on the rescheduling of rolling stock. Disruptions have a large influence on the... more
Railway operations are disrupted frequently. The disrupted situation requires to adapt the timetable and the resource schedules quickly. This research focuses on the rescheduling of rolling stock. Disruptions have a large influence on the passenger flows. The rolling stock schedule must be adapted such that there is on every train enough capacity for the modified passenger flows. To handle the modified flows it may be beneficial to adapt the stopping patterns of intercity trains to allow stops at regional stations. In this research we study a real time rolling stock rescheduling approach which determines if additional stops at regional stations are worthwhile.
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We give short elementary proofs of two results by N. E. Aguilera, M. S. Escalante, and G. L. Nasini on the disjunctive index of the clique relaxation of the stable set polytope.
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ABSTRACT This paper deals with real-time disruption management of rolling stock in passenger railway transportation. We describe a generic framework for dealing with disruptions of railway rolling stock schedules. The framework is... more
ABSTRACT This paper deals with real-time disruption management of rolling stock in passenger railway transportation. We describe a generic framework for dealing with disruptions of railway rolling stock schedules. The framework is presented as an online combinatorial decision problem, where the uncertainty of a disruption is modeled by a sequence of information updates. To decompose the problem and to reduce the computation time, we propose a rolling horizon approach: rolling stock decisions are only considered if they are within a certain time horizon from the time of rescheduling. The schedules are then revised as time progresses and new information becomes available. We extend an existing model for rolling stock scheduling to the specific requirements of the real-time situation, and we apply it in the rolling horizon framework. We perform computational tests on instances constructed from real-life cases of Netherlands Railways (NS), the main operator of passenger trains in the Netherlands. We explore the consequences of different settings of the approach for the trade-off between solution quality and computation time.
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ABSTRACT This paper studies the disruption management problem of rapid transit rail networks. We consider an integrated model for the recovery of the timetable and the rolling stock schedules. We propose a new approach to deal with... more
ABSTRACT This paper studies the disruption management problem of rapid transit rail networks. We consider an integrated model for the recovery of the timetable and the rolling stock schedules. We propose a new approach to deal with large-scale disruptions: we limit the number of simultaneous schedule changes as much as possible, and we control the length of the recovery period, in addition to the traditional objective criteria such as service quality and operational costs. Our new criteria express two goals: the recovery schedules can easily be implemented in practice, and the operations quickly return to the originally planned schedules after the recovery period. We report our computational tests on realistic problem instances of the Spanish rail operator RENFE and demonstrate the potential of this approach by solving different variants of the proposed model.
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This paper deals with real-time disruption management of rolling stock in passenger railway transportation. We present a generic framework for modeling disruptions in railway rolling stock schedules. The framework is presented as an... more
This paper deals with real-time disruption management of rolling stock in passenger railway transportation. We present a generic framework for modeling disruptions in railway rolling stock schedules. The framework is presented as an online combinatorial decision problem where the uncertainty of a disruption is modeled by a sequence of information updates. To decompose the problem we propose a rolling horizon approach where only rolling stock decisions within a certain time horizon from the time of rescheduling are taken into account. The schedules are then revised as the situation progresses and more accurate information becomes available. We extend an existing model for rolling stock scheduling to the specific requirements of the real-time case and apply it in the rolling horizon framework. We perform computational tests on instances constructed from real life cases and explore the consequences of different settings of the approach for the trade-off between solution quality and com...
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ABSTRACT In this paper we describe a two-stage optimization model for determining robust rolling stock circulations for passenger trains. Here robustness means that the rolling stock circulations can better deal with large disruptions of... more
ABSTRACT In this paper we describe a two-stage optimization model for determining robust rolling stock circulations for passenger trains. Here robustness means that the rolling stock circulations can better deal with large disruptions of the railway system. The two-stage optimization model is formulated as a large mixed-integer linear programming (MILP) model. We first use Benders decomposition to determine optimal solutions for the LP-relaxation of this model. Then we use the cuts that were generated by the Benders decomposition for computing heuristic robust solutions for the two-stage optimization model. We call our method Benders heuristic. We evaluate our approach on the real-life rolling stock-planning problem of Netherlands Railways, the main operator of passenger trains in the Netherlands. The computational results show that, thanks to Benders decomposition, the LP-relaxation of the two-stage optimization problem can be solved in a short time for a representative number of disruption scenarios. In addition, they demonstrate that the robust rolling stock circulation computed heuristically has total costs that are close to the LP lower bounds. Finally, we discuss the practical effectiveness of the robust rolling stock circulation: When a large number of disruption scenarios were applied to these robust circulations and to the nonrobust optimal circulations, the former appeared to be much more easily recoverable than the latter.
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ABSTRACT We provide a simple description in terms of linear inequalities of the convex hull of the nonnegative integer vectors xx that satisfy a given linear knapsack covering constraint ∑aixi≥b∑aixi≥b and have sum of the components that... more
ABSTRACT We provide a simple description in terms of linear inequalities of the convex hull of the nonnegative integer vectors xx that satisfy a given linear knapsack covering constraint ∑aixi≥b∑aixi≥b and have sum of the components that does not exceed 2. This description allows the replacement of “weak” knapsack-type constraints by stronger ones in several ILP formulations for practical problems, including railway rolling stock scheduling. In addition, we provide a simple description of the packing counterpart of the considered polytope, i.e. for the case in which the knapsack inequality is ∑aixi≤b∑aixi≤b (and again the sum of the components of the nonnegative integer vectors that does not exceed 2).
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ABSTRACT This paper deals with real-time disruption management of rolling stock in passenger railway transportation. We describe a generic framework for dealing with disruptions of railway rolling stock schedules. The framework is... more
ABSTRACT This paper deals with real-time disruption management of rolling stock in passenger railway transportation. We describe a generic framework for dealing with disruptions of railway rolling stock schedules. The framework is presented as an online combinatorial decision problem, where the uncertainty of a disruption is modeled by a sequence of information updates. To decompose the problem and to reduce the computation time, we propose a rolling horizon approach: rolling stock decisions are only considered if they are within a certain time horizon from the time of rescheduling. The schedules are then revised as time progresses and new information becomes available. We extend an existing model for rolling stock scheduling to the specific requirements of the real-time situation, and we apply it in the rolling horizon framework. We perform computational tests on instances constructed from real-life cases of Netherlands Railways (NS), the main operator of passenger trains in the Netherlands. We explore the consequences of different settings of the approach for the trade-off between solution quality and computation time.
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In the past decades extensive research has been conducted on optimizing the utilization of railway resources such as the infrastructure, the rolling stock and the crew (see Caprara et al. [1]). The developed methods have led to resource... more
In the past decades extensive research has been conducted on optimizing the utilization of railway resources such as the infrastructure, the rolling stock and the crew (see Caprara et al. [1]). The developed methods have led to resource schedules which are highly effective when ...