A multi-stage bulk materials acquisition system is examined from the viewpoint of dock operations. The whole process can be divided into four stages and treated as four subsystems: ships scheduling planning, material yard planning, dock arrangement, and material discharging. Since the structure and the complexity of each subsystem is diVerent, the solution approaches applied are also diVerent with respect to each. To increase operations eYciency and data consistency, an integration of the subsystems by coordinating the operations sequence and data communications for the four subsystems is discussed. The four subsystems are illustrated by using the material docks of China Steel Corporation, and the models developed in this research are also validated. The results indicate that the models developed are capable of deriving solutions better than the existing ones. Although the discussions are conWned to China Steel Corporation, the models can be applied to other companies with similar operations.The processes involved in the acquisition of raw materials include purchasing, transportation, and storage (see, for example, Evans, 1993). The purchasing process is related to strategy concerns such as relationships with vendors and consideration of a stable or sustainable materials supply, and the transportation and storage processes are related to the issues of operations and cost. The weight and volume of bulk materials are usually larger than those of processed material. Transportation by ships is the general means of obtaining bulk materials from overseas, and factories usually do not possess ships themselves. Rental costs are very high; if the ships' arrival times at the docks are not managed appropriately, demurrage for having to wait for berthing incurs a greater operating cost. Scheduling will depend on the kind of material carried and the dock situation related to the previous ships berthed. The tools and timing for transporting bulk material have to be arranged beforehand,
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