Information Technology Reference
In-Depth Information
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Fig. 8.
The simulation results with respect to the velocity of three pieces of equipment
by the hierarchical controller architecture
5 Conclusions and Future Research
In this paper, the dynamics of transporting containers in a container terminal
are considered as the combination of including continuous-time and discrete-
event dynamics. A hierarchical control architecture is proposed, consisting of
two levels. The higher level takes care of task scheduling; the lower level consists
of controller per piece of equipment for an optimal control problem. At the
higher level, the minimal makespan is obtained; at the lower level, the energy
consumption reduction is achieved if possible, while satisfying time constraints
on carrying out a task given by the higher level. A simulation illustrates how
the minimal makespan can be achieve in an energy-ecient way by the proposed
hierarchical control structure. Future work will extend the application toward
the transport of multiple containers by more than three pieces of equipment,
taking the potential collision of AGVs into account, and detailing the models
used to represent the continuous-time dynamics.
Acknowledgements.
This research is supported by the China Scholarship
Council under Grant 2010628012 and the VENI project “Intelligent multi-agent
control for flexible coordination of transport hubs” (project 11210) of the Dutch
Technology Foundation STW, a subdivision of the Netherlands Organization of
Scientific Research (NWO).
References
1. Alessandri, A., Cervellera, C., Cuneo, M., Gaggero, M., Soncin, G.: Modeling and
feedback control for resource allocation and performance analysis in container ter-
minals. IEEE Transactions on Intelligent Transportation Systems 9(4), 601-614
(2008)
2. Bielli, M., Boulmakoul, A., Rida, M.: Object oriented model for container terminal
distributed simulation. European Journal of Operational Research 175(3), 1731-
1751 (2006)
