【作者】 白大伟；

【导师】 史维峰；

【作者基本信息】 西北大学 ， 计算机应用技术， 2008， 硕士

【摘要】 随着全球竞争的不断加剧,制造业在产品的设计、制造与市场方面正面临着前所未有的挑战,传统的串行设计方法已经不能满足不断快速变化的市场需求。随着信息化进程的不断深入,计算机支持的协同工作(CSCW)正在受到日益广泛的重视并发挥重大作用,成为一个研究热点。本论文分析如何采用计算机及相关技术支持群组的协同工作,在此基础上改进一个基于CSCW的协同博士CAD原型系统,并对并发控制机制和访问控制机制进行了深入的研究。论文首先引出了协同系统的设计目标。通过对协同设计特点和协作方式的分析,对常用协同系统的体系结构进行了比较,分析了协同博士CAD系统的体系结构。接着通过对现有CSCW系统中采用的并发控制方法进行分析和讨论,研究了协同博士CAD系统中并发控制原则以及并发控制机制。论文在继续分析最初版本博士CAD系统的基于角色的访问控制RBAC以及第二版本博士CAD系统的基于角色的增强访问控制SRBAC的基础之上,提出了一种新的改进的访问控制模型BSRBAC,该模型能够比较好地解决以往博士CAD系统采用的访问机制所存在的问题。最后在协同博士CAD系统中应用了本文中提出的并发控制方法和访问控制机制。结果证明,本文提出的并发控制机制和访问机制是有效的,可行的,成功的。该系统具有开放式的结构,有效结合了本文提及的相关技术,对协同用户的操作具有高响应性、并发性和动态可适应性,并能及时有效地进行冲突处理。更多还原

【Abstract】 In this modern society, as global competition goes fiercer and fiercer, design, manufacturing and market of product are facing extreme challenge. Traditional serial design method can not face the need of continuously fast-changing market. Enterprises should make good use of information technology based on networks to promote their competitive strength with new designing and manufacturing mode. In this way, they can assemble scattered design resources quickly and, as a result, form a teamwork-collaborative design mode based on networks within the enterprise or between several enterprises. As the information process proceeds, computer supported collaborative work gets more and more attention and becomes a hot research area.This dissertation discusses on how to make use of computer and its related technologies to support teamwork and to implement a CSCW-based collaborative Dr. CAD system. Most important of all, concurrency control mechanism and access control mechanism are deeply discussed in detail.The whole design target of the system is proposed firstly. Collaborative design feature and collaborative method are analyzed and architectures of collaborative system are compared and the architecture of collaborative Dr. CAD system is described.The dissertation makes analysis and discussion of concurrency control method of currently available CSCW system and proposes the concurrent control principle and consistent model of collaborative Dr. CAD system.Furthermore, the paper proposes a new access control mechanism of Dr. CAD system called BSRBAC based on both RBAC in the initial version of Dr. CAD and SRBAC in the second version of Dr. CAD system. Theoretically, the new access control model can solve the problems occurred in previous versions of Dr. CAD system.Finally, the concurrency control and access control proposed in this dissertation are implemented in the Dr. CAD system.The experiment has proved that the Dr. CAD system has the open style structure and has effectively verified the related technology proposed in this paper. Dr. CAD has high responsiveness, concurrency and dynamic compatibility, and can carry on conflict processing effectively.更多还原