Tham khảo tài liệu 'manufacturing the future 2012 part 3', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Development of Holonic Manufacturing Execution Systems 91 Figure 7. Class Diagram of WIP Holon 92 Manufacturing the Future Concepts Technologies Visions When WIPManager gets the message CreateNewWIP from the Scheduling Holon a new WIP object is generated based on the data transferred from the Scheduling Holon. WIP object uses NewVariables operation in BOM to get the contents of BOM. WIP object uses the same approach to obtain ItemMaster information. Then WIP object gets order status and saves it. Up to this point initialization of WIP object is completed and it enters Wait for request state. At Wait for request state the WIP object can take commands such as track-in track-out and query. The query request will bring the WIP object to the Provide WIP status state and the WIP status is then sent to the requester. Track-out and track-in commands will update the WIP status and store it to database. During track-in operation the WIP object will check if this current process sequence is the last one or not. If it is not just jumps back to Wait for request state. If it is the last process this WIP object will be deleted and the memory will be released. It thus completes the life cycle of a WIP object. Note that the initial Generic Holon architecture shown in Fig. 4 only specifies the generic skeleton of the intelligence mechanism that consists of KnowledgeBase and LocalDatabase. After inheriting the Generic Holon to become a part of the WIP Holon its KnowledgeBase and LocalDatabase shall be trained to contain the specific knowledge information and rules for WIP holon s exception-diagnosis usage only. Now observing Fig. 8 a if an exception is occurred and detected during the WIP management process the system will enter the Diagnosing state that invokes SetExceptionTest of HolonKernel to diagnose the exception. If the cause is identified by the intelligence mechanism of the Generic Holon the system will enter the Recovery state that invokes the associated recovery operation
