| Internet supported collaborative design requests the design subjects distributed, which have different specialties using different design tools to execute the long-distance collaborative design in internet. In this sharing environment, the design subjects discuss and modify the design project repeatedly and complete the product design with the quickest speed and the best quality. Internet supported collaborative design requests all the correlative members can understand the related design project in time, can realize the progress state of design process at any time, can obtain the information of the stage design result dynamically, can share the design resources expediently, and can implement the collaborative exchange of mankind intelligence effectively. The work described in this paper was funded by the National Natural Science Foundation, China (No. 50175113) and the National Doctor Disciplinary Research Foundation (No. 20040611006). The data exchange and management technologies of internet-based collaborative design were researched. The major work described in this paper was as follows.①An internet supported collaborative design system structure based on three layers B/S system structure was built up. The function modules of the system structure were analyzed in detail. The system structure mainly realized the cross-platform modeling, the product data management, the data format transform, the database collaborative management and the system management functions. The key techniques of the system structure were analyzed, and the system packaging technique structure based on Web, CORBA and Agent was presented to resolve the interactive operation problem of collaborative design in distributed heterogeneous environment.②The ECA-based dynamic data exchange technique was presented. The key technologies in this technique, such as dynamic data exchange format, Standard for the Exchange of Product Model Data (STEP) and event-condition-action (ECA) rules were analyzed; the system structure of ECA-based dynamic data exchange was constructed; the STEP dynamic data exchange format was presented, the data format only included the STEP data of updating entities; the ECA rule in dynamic data exchange of internet supported collaborative design was defined, the basic relation of events defined in dynamic data updating was expressed by the complex operation and triggered relation of events; the ECA rule was adopted to monitor and identify the updating data of the model entities, only the updated data that satisfies conditions are transmitted, accordingly the data transmitted in internet is reduced and the possibility of unnecessary data created in updated data is lowered. A locking concurrency control mechanism is implemented to resolve the interactive conflict in multi-users.③The role-based collaborative design system access control model was constructed. The factors of access control and various access control mechanisms were analyzed. The role-based access control (RBAC) models were summarized in detail and the characteristic and usability of RBAC were analyzed. From the protection of sensitive information, the role-based collaborative design system access control (RBCDSAC) model was presented in which the Mandatory Access Control (MAC) was integrated in RBAC framework. The relative conceptions of RBCDSAC model were defined. Access control matrix was constructed to control the users'accesses. In internet supported collaborative assembly design, the model can protect the sensitive information effectively and increase the security of internet supported collaborative design.④By analyzing the characteristic, the study and develop approach and the key techniques of collaborative database, the collaborative database management system, and a collaborative database model based on Multi Agent System (MAS) was constructed. The key technologies were studied and the excellence of collaborative database model was discussed. The data query disposition of collaborative database system was studied. The query disposition structure of collaborative database system was constructed. The global query decomposition and global query optimization were studied in detail. The global query decomposition algorithm was developed and the multi-regression cost model of query cost was presented. And partial least squares regression (PLS) was adopted to seek the query cost, and the optimized query project was obtained by comparing the query cost and threshold. The version management mode based on object was constructed to solve the data version management problem in collaborative database system.⑤The research example to verify the related theories in this paper was developed. The Web-based product collaborative design prototype system was constructed. The prototype system realized product collaborative design by the development of function modules, such as collaborative conference, product structure design, product structure strength analysis, etc.
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