节点文献
网络化工业组态软件实时数据库研究与实现
【作者】 祖一康；
【导师】 何鹏举；
【作者基本信息】 江西理工大学 ， 控制理论与控制工程， 2009， 硕士
【摘要】 实时数据库是网络化测控系统的核心软件之一,其在自动控制、通信、电力、证券交易等行业都有着广泛的应用市场,但国内的实时数据库目前没有商业化产品,实时数据库一般作为应用系统的一部分,国外的实时数据库价格昂贵,一般用户消费不起,而网络化测控技术是近几年刚刚兴起的一门新兴的测控技术,对实时数据库又提出了新的要求。为此,研究开发一种适合网络化测控的实时数据库就显得格外的重要和必要。论文围绕网络化工业组态软件实时数据库进行了研究和开发,主要的研究工作如下:1.论述了国内外实时数据库研究现状,在深入分析其原理与结构的基础上,结合网络化测控自身特点,设计了一种适合网络化工业组态软件的实时数据库体系结构;2.研究了实时数据库的物理数据组织以及索引技术,分析了顺序索引、Hash索引、B树索引、AVL树索引、T树索引,并进行了性能比较,通过比较选择T树作为索引结构;3.在研究实时事务调度和并发控制的基础之上,得出了同时考虑实时事务和数据截止期的调度机制;详细论述和讨论了两段锁和乐观并发控制机制,并对两种机制进行了比较,提出了一种新的并发控制算法:区分只读事务(单独处理只读事务)算法即SA算法,通过实验得出,SA算法在只读事务占主导地位的系统中,可以很好的改善系统的并发控制性能;4.基于μC /OS?ΙΙ实现了实时数据库系统,并实现了一种网络化测控系统。具体实现方法是在μC /OS?ΙΙ上移植uC/FS文件系统,采用μIP作为TCP/IP通信协议,构建了Web服务器实现与客户端的实时通信;同时,在客户端开发了相应的监控组态软件,以保证对实时数据的现场监控。本文设计开发的网络化组态软件实时数据库已在实验室的网络化测控系统中得到了应用。通过实验表明,本文设计的组态软件实时数据库系统是可行的,这为实时数据库系统的应用又提供了一种工程实现方案。
【Abstract】 Real-time database is one of the core software in networked measure and control system, it has widely used market in automatic control、communication、electric power、stock trading and so on, but the domestic real-time database has no commercial products at present, real-time database usually used as one part of application systems, the foreign real-time database is so much expensive that the general users can’t afford it, however, networked measure and control technology is a new measure and control technology which has come up for only few years, it poses a new require to the real-time database. So research and develop real-time database systems which is adapt to networked measure and control is very important and necessary. This thesis is mainly about the research and development of Real-Time database of supervisory control and data acquisition configuration software, main research works are as follow:First: Discussed the internal and external real-time database research situation, on the base of deep analyze, integrate with characteristic of the networked measure and control, and engage networked industrial supervisory control and data acquisition configuration software and real-time research and design;Second:Research the physical data organization and the index technology of the real-time database, analysis sequence index、Hash index、B-Tree index、T-Tree index, and with the comparance of the common indexes each other, choose the T-Tree as index structure;Third: On the based of research of the real-time transaction schedule and concurrency control, give out a schedule mechanism which consider the deadline of transaction and data simultaneously; detail elaborate and discussion 2PL and OCC concurrency control mechanism, and compared the two mechanisms, raised a new concurrency control algorithm: distinguish read only transactions (separate handle read only transactions) algorithm, that is, SA algorithm, by means of experiment concludes that SA algorithm in the systems which read only transactions predominant, can improve the concurrency control performance;Forth: Based on theμC /OS?ΙΙrealized the real-time system, and at the same time realized the networked measure and control system. The detailed realized methods are: transplant the uC/FS to theμC /OS?ΙΙ,usingμIP as the TCP/IP communication protocol , construct the Web server to reallize the real-time communication to the client; and develop supervisory control and data acquisition configurat ion software in the client to real-time supervisory control industrial spot.The networked supervisory control and data acquisition configurat ion software with real-time database has been applied in our networked measure and control laboratory. The experiment shows that the design of networked supervisory control and data acquisition configurat ion software with real-time database in this thesis is feasible, so this provides another engeneering realization method of the application of the real-time database.