الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Dial-a-Ride Problem (DARP) is a door-to-door transport service. This system is based on a fleet of vehicles, travelling through flexible routes to pick up and DROP off users at their own time and place. On the other hand, the integrated dial-a-ride problem (IDARP) integrates the regular DARP with a fixed-route transport system. The DARP usually serves the first and last miles of in multimodal journeys while the fixed-route service carries out the longest part of the journey. The primary focus of the integrated system is usually to obtain the optimal routes of a set of DARP vehicles. However, the basic IDARP has particular issues. It only integrates a single fixed line. It does not serve any request from the non-integrated service (regular DARP). Furthermore, the transfer node system grows quickly with each new request. Therefore, it requires more strengthening strategies for the problem to be computationally tractable. The proposed model is the integrated dial-a-ride problem fixed-route selection (IDARP-FRS); it overcomes the aforementioned IDARP issues. The IDARP-FRS is an innovative transport system for a better quality of life and more predictable journey durations. The IDARP-FRS introduces a number of contributions. It models several fixed lines in two different ways. An additional set of constraints is devised to possibly serve some users from regular DARP (with no integration). The IDARP-FRS also introduces a set of newly constructed direction-based constraints inspired by a fundamental aspect of the fixed-route service. These constraints are useful in controlling the service quality and preventing users from traveling in the opposite direction of their destination. These direction-based constraints also have the potential to suppress the number of transfer node arcs, thus reducing the size of the underlying problem. The IDARP-FRS additionally includes the symmetry-breaking constraints. They are brought from the literature to the context of the IDARP-FRS to strengthen the model further. The computational tests were implemented on Gurobi Solver academic version using Python interface on Windows 10, i7, and 8GB memory. The results obtained demonstrate the capability of the proposed model in choosing among different fixed lines. The IDARP-FRS has the potential to reduce the total travelled distance, which benefits all stakeholders, including users, operators, and the environment. It also serves requests from the non-integrated service (DARP), and therefore it can serve different segments of users. The outcomes of computational tests prove and show the significant role of the proposed constraints in reducing the problem complexity