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Tham khảo tài liệu 'the design of manufacturing systems part 5', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | contemporary FMS necessitate the development of automated solutions to the deadlock problem. It has become clear by now that establishing nonblocking behavior for the automated FMS is a prerequisite to any performance optimizing policy. Because the primary cause for the deadlocking effects in contemporary FMS is the ineffective allocation of its buffering capacity in the subsequent analysis we shall focus on this capacity of the FMS workstations and MHS ignoring the detailed operational content of the different processing stages. Hence all different classes of FMS equipment able to stage a part will be collectively characterized as the FMS resources. However an additional aspect of the FMS operation to be taken into consideration during the FMS structural analysis is the management of the system auxiliary equipment that is the available pallets fixtures and cutting tools. Specifically if there are sufficient units of this kind of equipment and or every job is allocated the required auxiliary resources when loaded into the system and it keeps it until exiting the management of this set of items is not a cause of deadlock. On the other hand if auxiliary equipment is scarce and it is allocated to the requesting jobs only prior to executing the corresponding processing step s in an exclusive nonpreemptive manner then it should be obvious that careless management of these resources can give rise to circular-wait situations and therefore to deadlocks. A third feature that is relevant to the characterization of the FMS structural behavior is whether the routing of a certain part processed through the system is determined online dynamic routing or during the loading of the part into the system static routing . The issue here is that the machine flexibility 27 implemented in modern manufacturing processors as well as the operation flexibility 27 supported by the design of the various products run through the system allows for the production of a certain part through a .