The Chair of Transportation Systems Engineering of TUM invites you to a seminar with Dr. Saeid Saidi, Associate Professor at the University of Calgary, where he will talk about his work on developing a hybrid optimization approach for extending an existing network of surface express transit networks.
When: Friday 14th November 2025, 13 - 14:00
Where: Technical University of Munich, TSE office. Address: Parkring 37, Garching by Munich, Lageplan, Direction. The seminar will be held in TSE’s office meeting room. The entrance to the office is on the right of the EDEKA store, and the office is on the left-hand side of the 1st floor.
This is a free admission event. Contact: Chair of Transportation Systems Engineering e-mail: apply.vvs(at)ed.tum.de.
More information
A Hybrid Optimization Approach for Surface Express Transit System Planning for Extending an Existing Network
Saeid Saidi, Reza Mahmoudi, S.C. Wirasinghe
Existing research has predominantly concentrated on designing a new transit network without considering the pre-existing network. However, the majority of problems involve redesigning or extending an already existing network. Considering the pre-existing multi-modal transit network in a city, we have integrated analytical methodologies and mathematical programming to formulate a two-stage approach for addressing the bi-modal express transit network design problem within the context of a surface express transit system. In the first stage, we use analytical approaches and continuum approximations to identify the optimal locations of new stations. In the second stage, mathematical programming is proposed to simultaneously determine the optimal layout of express transit routes, the technology of each transit route, and the service headway associated with all transit routes (i.e., existing and new routes). Then, a metaheuristic algorithm based on a Genetic Algorithm is introduced to solve the proposed mathematical programming for real-size transit networks. The proposed approach has then been applied to the express transit network of Calgary, Canada, a large-sized bi-modal express network. The bimodal express transit network design problem has been solved for Calgary under various scenarios, and the results have been discussed. Analyses show that, in the proposed hybrid approach, solving a part of the problem analytically reduces its complexity significantly and enables parametric analysis, while using mathematical programming helps to address the complexity of express transit network design problem for real transit networks. The proposed approach stands out from existing similar studies due to its departure from simplifying assumptions concerning network topology, the city’s structure, capturing any type of demand patterns, model flexibility to for existing transit network extension, and multi-modality of the express transit network.
Full publication available at Transportation Research Part E: Logistics and Transportation Review
About the speaker
Dr. Saeid Saidi is an Associate Professor in the Department of Civil Engineering at the University of Calgary. Prior to joining the University of Calgary, he was a Postdoctoral Associate at the Institute for Data, Systems and Society (IDSS) at Massachusetts Institute of Technology (MIT) and a member of the MIT Transit Lab. He earned his PhD and MSc in civil engineering with transportation engineering specialization from the University of Calgary. He received his bachelor’s degree in industrial and system engineering from the Sharif University of Technology. Dr. Saidi’s main research activities are on transportation network modeling, public transportation planning and operation, and big data analytics using mobility sensing data. He is working on different applications of data analytics in transportation systems to create actionable intelligence for cities and transportation authorities. He has more than 50 peer-reviewed journal and conference publications. He serves as the Vice Chair for CUTRIC’s Academic Committee for Transit Innovation. He also served as a member of for the Transportation Research Board (TRB) National of Academies – Rail Transit System Committee (AP065) for 9 years.