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According to APICS dictionary, the definition of protective capacity is: "A given amount of extra capacity at non- constraints above the system constraints capacity, used to protect against statistical fluctuation ( breakdowns, late receipts of materials, quality problems, etc.)." That is, the protective capacity provides non-constraints with the ability to "protect" throughput and due date performance.This thesis applies float-time oriented scheduling method to set protective capacity. It can cope with disruptions from three different phases: (1)First phase: using float time to construct a robust schedule; (2)Second phase: deriving the priority order for control, according the float-time indexes; (3)Third phase: using protective capacity to catch up the planned pace, when disruptions occur. Thus, this method not only strengthens the robustness of a schedule, but also offer a way of capacity management that can be really functioned when the system is suffered disruptions.The thesis also proposes the principles of initiator's actions for using the protective capacity. The principles include: How to identify non-constraints that need to set protective capacity? When is needed? How to cooperate the related resources? How to decide the level of protective capacity? And when to exhaust the protective capacity?The simulation results show that better performance is achieved on both the cycle time and the work-in-process level when following the principles of initiator's actions. This is done because that the float-time oriented scheduling method ensures the production of parts at right time, right quantity and right place.
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