Scheduling mechanisms for rail mounted gantries with respect to crane interdependencies

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Rail mounted gantries are a relatively new device for handling containers in stacks in a port container terminal. Consequently, scheduling approaches for rail mounted gantries are scarce. Most of existing approaches do not consider that in settings with multiple gantries per container block these gantries cannot move or operate independent from each other. This issue is resolved often by assigning disctinct areas to gantries. Mostly gantries then are restricted to operate in the assigned area only. Obviously, this reduces flexibility significantly. Therefore, it is necessary to develop mechanisms which allow to schedule gantries without restriction to areas and integrate dependencies which may or may not occur depending on the schedule in the decision process. This does happen in existing literature only very rarely. In particular no polynomial algorithms have been developed for subproblems nor have they been proven to be non-existent.The goal of this project is to close this research gap. We will follow a bottom-up approach. First, we consider subproblems and develop efficient solution methods for them. Step by step we consider more integrated scheduling problems using the approaches developed for subproblems so far as building blocks. The final outcome is a method for integrated scheduling of rail mounted gantries considering crane inter-dependencies. In particular we aim at considering that transport devices handing over containers to rail mounted gantries or receiving containers from them are in competition with each other (each truck driver desires to be served first). In our scheduling approach mechanisms shall be integrated which allow to resolve this issue in a fair manner.The methodology used encompasses techniques from the fields of linear, integer, and mixed-integer programming, applied computer science (graph theory, e.g.), scheduling theorie, game theorie and computational complexity theory.