Optimal rerouting of short-turning trains during track obstructions

Railway trafic controllers have only limited decision support to deal with disruptions. The aim of this research is to provide an algorithm to compute conflict-free routes for trains that cannot continue their planned operation due to a track obstruction. In case of complete blockage, trains need to short-turn at the closest possible station to...

Cost optimal river dike design using probabilistic methods

This research focuses on the optimization of river dikes using probabilistic methods. Its aim is to develop a generic method that automatically estimates the failure probabilities of many river dike cross-sections and gives the one with the least cost, taking into account the boundary conditions and the requirements that are set by the user....

Validation and Optimization of a Design Formula for Stable Geometrically Open Filter Structures

Granular filters are used for protection against scour and erosion of base material. For a proper functioning it is necessary that at the interfaces between the filter structure, the subsoil and the water flowing above the filter structure no material will be transported. Different types of granular filters can be distinguished, this paper...

Rolling horizon predictions of bus trajectories

Bus travel times are subject to inherent and recurrent uncertainties. A real-time prediction scheme regarding how the transit system evolves will potentially facilitate more adaptive operations as well as more adaptive passengers’ decisions. This scheme should be tractable, sufficiently fast and reliable to be used in real time applications. For...

Risk approach to land reclamation: Feasibility of a polder terminal

New ports are mostly constructed on low lying coastal areas or shallow coastal waters. The quay wall and terminal yard are raised to a level well above mean sea level to assure flood safety. The resulting ‘convention-al terminal’ requires large volumes of fill material often dredged from the sea, which is costly. The terminal yard of a ‘polder...

Risk based design of land reclamation and the feasibility of the polder terminal

New ports are mostly constructed on low lying coastal areas or in shallow coastal waters. The quay wall and terminal yard are raised to a level well above mean sea level to assure flood safety. The resulting ‘conventional terminal’ requires large volumes of good quality fill material often dredged from the sea, which is costly. The alternative...

An Optimization Model for Simultaneous Periodic Timetable Generation and Stability Analysis

We present an optimization model which is able to generate feasible periodic timetables for networks given the line structure and the requested line frequencies, taking into account infrastructure constraints and train overtake locations. As the model uses the minimum cycle time as the objective function, the stability of the timetable is also...

Estimates of extremes in the best of all possible worlds

In applied hydrology the question of the probability of exceeding a certain value occurs regularly. Often it is in a context where extrapolation from a relatively short time series is needed. It is well known that in its simplest form extreme value theory applies to independent identically distributed random variables. It is also well known that...

A generic method to optimize instructions for the control of evacuations

A method is described to develop a set of optimal instructions to evacuate by car the population of a region threatened by a hazard. By giving these instructions to the evacuees, traffic conditions and therefore the evacuation efficiency can be optimized. The instructions, containing a departure time, a destination, and a route, are created...

Efficient particle-based estimation of marginal costs in a first-order macroscopic traffic flow model

Marginal costs in traffic networks are the extra costs incurred to the system as the result of extra traffic. Marginal costs are required frequently e.g. when considering system optimal traffic assignment or tolling problems. When explicitly considering spillback in a traffic flow model, one can use a numerical derivative or resort to heuristics...