The Design And Implement Of N-tier CAPP System Based On Distributed Database For DHI

A typical CAPP system structure in distributed and Heterogeneous data environment is constructed by the research of developing trend of the modern CAPP and performance analyzing to the process system of Dalian Heavy Industry Company, furthermore layered design idea based on flowing status of data is brought forward, moreover, a N-tier CAPP system is implemented in software level adopting the component program idea. Then, corresponding client program is developed using these components, which is applied in the CAPP platform of Dalian Heavy Industry Company.Firstly, the function and system structure which a modern CAPP system should have are summarized by analyzing the current situation and development of CAPP system and summing up the character for several large-scale CAPP systems, which confirmed the developing object for function and system of CAPP system. Also the function flow and system structure are designed with N-tier and distribute character in the guidance of this object.Secondly, According to the life cycle of process file, the function component layer is designed as emphasis, the main models for CAPP such as the model of the convert and management for process BOM, the model of card design, the model of version control, the model of right control, the model of process data consuming, the model of process flow control, are analyzed and designed in detail and coded, Which provided the interface and implement of function component layer.Thirdly, the distribute database structure is designed. The factor of speed and performance is considered in General Design. And the tables and fields are designed in the constraint of the 3NF. The database access layer is abstracted to implement the compatibility for Heterogeneous data and distributed design and the shield for detail to up layer. The two version of data access component: sqlServer and Oracle are developed.Finally, the web client program, the structure part client program, and the main client program are developed in the requirement of DaLian Heavy Industry Company, which validated the quickly respondence due to the component and layered design and the adaptive capability to distribute and heterogeneous data environment.