University of Kashan Soft Computing Journal 2322-3707 13 1 2024 08 22 Designing a stable model for the Tehran subway train scheduling problem with a robust optimization approach Designing a stable model for the Tehran subway train scheduling problem with a robust optimization approach 76 95 114253 10.22052/scj.2024.248714.1120 FA Davood Jafari Faculty of Industrial Engineering, Islamic Azad University, Parand Branch, Tehran, Iran. Mehran Khalaj Faculty of Industrial Engineering, Islamic Azad University, Parand Branch, Tehran, Iran. Pejman Salehi Faculty of Industrial Engineering, Islamic Azad University, Parand Branch, Tehran, Iran. Journal Article 2022 12 19 This study aims to present a robust optimization model for scheduling intra-city rail transport trains (metro) in Tehran. We present a new approach based on robust principles and concepts to tackle the challenge of timetable planning for Tehran's subway trains under uncertainty and disturbances. To this end, a simulation method is employed, considering buffer times and minimum train movement intervals. Therefore, this paper follows a linear programming framework to determine the optimal headway distances for Tehran's subway lines, with the goal of minimizing average waiting times at station platforms and enhancing train flow according to passenger demand. Using a general linear programming model, after defining the objective function and constraints—such as train stopping times at stations (nodes), route lengths (edges), station capacities, and safety margins in line with the overall rail network conditions—optimal points are identified through buffer times and simulation approaches, exemplified at Shahed station, and incorporated into the final timetable design. Additionally, this work assumes that parameters related to capacity and timing of train units are non-deterministic. At the end, the validity of the proposed model is evaluated using data from the southern part of line one of Tehran's subway, and the results are presented. This study aims to present a robust optimization model for scheduling intra-city rail transport trains (metro) in Tehran. We present a new approach based on robust principles and concepts to tackle the challenge of timetable planning for Tehran's subway trains under uncertainty and disturbances. To this end, a simulation method is employed, considering buffer times and minimum train movement intervals. Therefore, this paper follows a linear programming framework to determine the optimal headway distances for Tehran's subway lines, with the goal of minimizing average waiting times at station platforms and enhancing train flow according to passenger demand. Using a general linear programming model, after defining the objective function and constraints—such as train stopping times at stations (nodes), route lengths (edges), station capacities, and safety margins in line with the overall rail network conditions—optimal points are identified through buffer times and simulation approaches, exemplified at Shahed station, and incorporated into the final timetable design. Additionally, this work assumes that parameters related to capacity and timing of train units are non-deterministic. At the end, the validity of the proposed model is evaluated using data from the southern part of line one of Tehran's subway, and the results are presented. https://scj.kashanu.ac.ir/article_114253_5f7fdf27e7394a046ca198b1a6861120.pdf