On-demand rail-bound system

On-demand public transport is expected to become an increasingly important component of public transport systems, facilitated by vehicle automation. The potential of rail-bound on-demand services has been largely overlooked. Together with Jesper Haverkmap, who did his master thesis in the Dutch Railways, we determine the capacity requirements of an envisaged automated on-demand rail-bound transit system which offers a direct non-stop service.

The full paper published on Transportation Research Part B: Methodological is available here.

How many vehicles would such a system require? What are the costs associated with such a system? What are the track and station capacity required? What level of service will it deliver? What are the network saturation patterns given that vehicles can now perform route choice and choose the shortest path to passengers’ destination? What are the consequences for equity in service provision?

An optimization model is formulated for determining the optimal track and station platform capacities for an on-demand rail transit system so that passenger, infrastructure and operational costs are minimized. The macroscopic model allows for studying the underlying relations between technological, operational and demand parameters, optimal capacity settings and the obtained cost components.A series of sensitivity analyses are performed to test the consequences of a range of network structures, technological capabilities, operational settings, cost functions and demand scenarios for future automated on-demand rail-bound systems.

The model is applied to a series of numerical experiments followed by its application to part of the Dutch railway network. The performance is benchmarked against the existing service, suggesting that in-vehicle times can be reduced by 10% in the case study network while the optimal link and station capacity allocation is comparable to those currently available in the case study network. While network geometry and demand distribution are always the underlying determinants of both service frequencies and in-vehicle times, line configuration is only a determinant in the conventional system, whereas the automated on-demand rail service better caters for the prevailing demand relations, resulting in greater variations in service provision.

Here is a clip made by the Dutch Railways (NS) on the concept of on-demand services, denominated as Swarming transport. 



Awarded with an ERC Starting Grant

I am honored and delighted to be awarded with an ERC (European Research Council) Starting Grant. My project CriticalMaaS will develop and test concepts, theories and models for planning, operating and evaluating the dynamics of Mobility as a Service.

The project will run for 5 years and will be performed by a team of PhD students, post-doc researchers and in collaboration with colleagues within the Department of Transport and Planning at TU Delft and beyond.

See the announcement on the ERC website
and on the Faculty news.

PhD defense and TRAIL seminar

Congratulations Dr. Nadjla Ghaemi for successfully defending your PhD dissertation on “Short-turning Trains during Full Blockage in Railway Disruption Management” today!

Nadjla’s PhD work has been published in the following journal publications:

Ghaemi N., Cats O. and Goverde R.M.P. (2018). Macroscopic multiple-station short-turning model in case of complete railway blockagesTransportation Research Part C, 89, 113-132.

Ghaemi N., Cats O. and Goverde R.M.P. (2017). A Microscopic Model for Optimal Train Short-Turnings during Complete BlockagesTransportation Research Part B, 105, 423-437.

Ghaemi N., Zilko A., Yan F., Cats O., Kurowicka D. and Goverde R.M.P. (2018). Impact of Railway Disruption Predictions and Rescheduling on Passenger Delays. Journal of Rail Transport Planning & Management. Accepted.

Ghaemi N., Cats O. and Goverde R.M.P. (2017). Railway Disruption Management Challenges and Possible Solution DirectionsPublic Transport, 9 (1-2), 343-364.

The defense was followed by a TRAIL seminar where I gave a talk on “Robust passenger transport systems: Network, operations and user adaptations”

ITS Berkeley seminar

Monday, April 16, 2018 – , 1:00pm to 2:00pm, 212 O’Brien Hall

ITS Berkeley seminar announcement

Seminar abstract: The metropolitan passenger transport landscape is shifting due to a combination of technological and social developments which enable both service providers and service users to become increasingly adaptive. Service providers can manage their resources to better cater for prevailing demand patterns, while service users can adjust their behaviour in response to real-time information. In this seminar, I will present our work on modelling system dynamics and the interaction between supply and demand under uncertainty in relation to tactical planning (e.g. fleet size and composition, frequency setting) and real-time management (e.g. trip dispatcher, disruption management) of fixed line-based as well as flexible on-demand services.

Method for the reliable determination of service frequencies

Service reliability is often considered only at the operational management phase, while services are assumed to be perfectly reliable at the strategic and tactical planning phases. However, service (un)reliability has consequences on the effective frequency and thus on deficiencies in capacity allocation and passenger waiting times and on-board comfort.

Determining the dispatching headways of bus services in a city network is a multi-criteria problem that typically involves balancing between passenger demand coverage and operational costs.

Together with Costas Gkiotsalitis from NEC Labratories Europe, we develop and apply a reliability-based optimization framework for setting the dispatching headways of bus lines that considers historical operational data and is aware of the passenger waiting time variability at each stop and how it is affected when changing the planned dispatching headways.

Check out the full paper published on Transportation Research Part C – Emerging Technologies following this link

We hope that this work will contribute to a new generation of tactical planning methods that account for service uncertainty.