Component Technology And Research On Integration Methods In PDM System

With the development of network technology, the network has connected computers separated. The computing mode has changed from traditional host-centered to network-centered. This transform resulted in a new challenge to the exploitation software. Under this mode, program must resolve the distribution, heterogeneous under environments of network and the interoperability between applications. So traditional methods about software exploitation can't meet the needs of it.In 1990s, the exploitation methods based on component became the important symbol of exploitation technology of software. It decreases the complexity of program and improves the ratio of application reuse; furthermore it avails to upgrade and maintain of software. At present, distributed object running environments CORBA of OMG and DCOM of Microsoft are popular. Both sustain the running environments platform-independent of component. They provide efficient way to resolve the problems of distribution computing and interoperability under environment of network.PDM integrate and manage all information of product lifecycle from design to production and production to user. It is also an integration tool connecting different departments, different areas and guarantees the cooperation between corporations. It is necessary to combine PDM with WEB; this kind of system becomes a web database application system in essence. In this paper, I do two aspects mainly. The first aspect, I import CORBA technology into PDM system structure and put forward a systemstructure based on CORBA/WEB mode. This kind of structure expands the hierarchy of applications and becomes a multi hierarchy system structure. It resolved the abuse of single hierarchy and double C/S hierarchy, build up the tolerance mechanism and load balance. At last, I give an example using this kind of structure about document management of PDM system. The second aspect. I mainly discuss the application of CORBA technology in system integrity of PDM. Because the data managed by PDM come from various softwares and machines, and sometimes information exchange and share are necessary between PDM system and other systems applied in practice. Therefore, system integration is the important question for discussion in PDM system. The idea of ORB soft bus and its properties of platform-independent, migration and interoperability provide support in technology for system integration between PDM system and other applications(CAX, MRP II etc). But integration with CORBA depends on opening of both sides and supporting to CORBA. What 1 do mainly in this section follows: Firstly, I discuss some integration methods between PDM and CAX, MRP II,PDM and subsystem ,PDM and old system , describe the method and frame model for system integration with CORBA. Secondly, I design the antitype that PDM integrated MRP II with CORBA, discuss the process of development of system integration with CORBA. Finally, I-provide a method that can integrate PDM and CAD system. It is a method using ActiveX Automation technology on PDM platform.Chapter one is generality. I denote the abuse of traditional method in software development by the analysis of direction to software development and advance to develop application system with component, bring forward the definition of component, and point out the differences and relations between component and technology object-oriented. At last, I figure out the emphasis in this paper.I put forward a system construction based on CORBA/WEB in chaptertwo, and state its advantage and necessity after discussing the old-fashion system construction: single-layer, C/S and three-layer. Finally, I do an example of document query and express its application in practice.Chapter three is about distribution component. First, I analyze the component of CORBA, DCOM, and EJB in integration, usability and expansibility and conclude CORBA is predominant in platform-independence. So it is selected as an integration platform of PDM. Next, I state the construction and interoperability of CORBA...