DEVELOPMENT OF A REAL-TIME DATABASE-MANAGEMENT SYSTEM FOR PRODUCTION PROCESS-CONTROL APPLICATIONS

초록

Computers are becoming more widely used in a large number of the complicated scientific applications such as aerospace and defense systems, nuclear reactor control, and computer integrated manufacturing(CIM) with their ever-increasing performance-price ratio. These applications require not only complex scientific processing/analysis but also real-time processing for their data to control external devices correctly. To support real-time applications, a real-time database system which satisfies the requirements of timing constraints in collecting, updating and retrieving data is needed. This paper describes WatchMan, a real-time database system which supports engineering data required in CIM applications in monitoring and controlling machines in the factory. In order to provide real-time processing features, the real-time database system manages all data as a main memory database. A new storage structure and an access method appropriate for main memory databases have been developed for this purpose. Also, concurrency control and recovery techniques suitable for the real-time processing in the CIM environment have been proposed. In addition, this paper presents solutions to the problems which result from developing the main memory databases under Unix system.