Anders Peterson

Quantifying railway timetable robustness in critical points

Several European railway traffic networks experience high capacity consumption during large parts of the day resulting in delay-sensitive traffic system with insufficient robustness. One fundamenta ...

Allocation of Link Flow Detectors for Origin‐Destination Matrix Estimation—A Comparative Study

Origin-destination (OD) matrices are essential for various analyses in the field of traffic planning, and they are often estimated from link flow observations. We compare methods for allocating lin ...

Improving paratransit scheduling using ruin and recreate methods

Abstract In this paper we study the effects of using ruin and recreate methods in a replanning phase of a dynamic dial-a-ride problem. Several such methods are proposed, and a modeling system is used to evaluate how they improve the quality of the solutions. We show that simple changes to existing planning methods can increase the efficiency of the service. Two cases, with different forms of costs inflicted on the vehicles, are evaluated and significant improvements are found in both cases. The best results of our study are found with ruin methods based on removal of sequences of requests.

Towards a robust traffic timetable for the Swedish Southern Mainline

We identify the on-time performance as a key to evaluate a railway timetable’s robustness to disturbances and evaluate the on-time performance for two single services on the Swedish Southern Mainline for the autumn period 2011. We analyse the punctuality by studying how the performance develops en route. Typically the time spent in the stations is underestimated, which partly is compensated for by time margins along the line, giving rise to a sawtooth formed delay muster with an increasing trend. The standard deviation in the delay reports seems to be a good indicator for the precision in the traffic. In this material it is almost linearly increasing with a good minute per hour scheduled running time. Two attempts are made to change the timetable for a better performance. By using socio-economic values a customer-oriented description of the current timetable is calculated as a trade-off between high punctuality and short travel time. This timetable does not affect any other traffic. Minor effects to other traffic would be the result if the existing margins are re-distributed to better match the demand en route in some sense. As long as no more time supplement is added, we will, however, not improve on the punctuality to the final destination. For future research is left, how the decrease in precision can be accounted for already in the timetable construction.

Local performance measures of pedestrian traffic

Efficient interchange stations, where travelers are changing lines and/or travel modes, are essential for the functionality of the whole public transport system. By studying pedestrian movements, the level of service and effectiveness imposed by the design of the interchange station can be evaluated. We address the problem by microsimulation, where a social force model is used for the phenomenological description of pedestrian interactions. The contribution of this paper is the proposal of measures describing the density, delay, acceleration and discomfort for pedestrian flows. Simulation experiments are performed for the movements in two canonical pedestrian areas, a corridor and a corridor intersection. Clearly, each of the four measures gives a description for how pedestrians impede each other, and hence for the efficiency at the facility. There is, however, different information provided by each measure, and we conclude that they all are well-motivated for quantifying the level of service in a pedestrian flow. We also illustrate the outcome for a railway platform, with two trains arriving in parallel.

A microscopic evaluation of railway timetable robustness and critical points

One method to increase the quality of railway traffic flow is to construct a more robust timetable in which trains are able both to recover from delays and the delays are prevented from propagating ...