摘要
带有对象的Petri网是一种将面向对象的方法和谓词 /变迁网相结合的高级Petri网。网中的托肯能携带各种信息 ,用这种网所表述的系统具有规模小、灵活、直观、模块性好、可操作性良好、属性描述方便、有利于不确定问题的处理等优点。针对列车群运行控制的核心问题 (列车群行为建模 ) ,用精确标识的PNO建立了一个具有普适性的模型 (TOPNO) ,该模型是一个典型的离散事件动态系统。通过在对象中定义多种模糊属性和相应的模糊属性的调整方法 ,该模型就成为研究模糊离散事件动态的平台 ,使得面向对象的程序设计技术、Petri网的理论和应用、模糊集理论以及DEDS的理论及分析方法有机的结合起来。在网络的变迁规则中直接引用这些属性 ,使系统的决策机制更有效 ,简化了系统状态的演化 ,并使DEDS的理论在处理不确定性问题时得到延伸 ,从而为建立具有自动行车指挥的智能交通系统奠定了良好的基础 ,也为铁路系统的可靠性分析、可利用性分析、效率分析等问题的处理提供了新的途径。
The Petri net with objects (PNO) is a kind of high-level Petri net which integrates the object-oriented approach and the predicate/transition nets. Its token can carry various kinds of information. The system described by this Petri net features small scale, flexibly, directly perceivable, fit for modularization, good controllability, easy to describe nature and easy to process uncertain issues. In order to solve the key problem of train operation control (modeling train operation), the paper uses PNO with precise marking to model train operation (TOPNO), which has better accommodation. It is a typical discrete event dynamic system (DEDS). By means of defining fuzzy attribute in the objects and their operating methods, this model becomes the platform to study fuzzy DEDS and to make it possible to integrate objects-oriented approach, the theory and application of Petri nets, fuzzy set theory and the analysis methods of DEDS. The direct citation of these fuzzy attributes in the transition rules makes the system decision more efficient and the system state evolution simplified. TOPNO with fuzzy attributes extends the theory of DEDS in processing uncertain issues. As a result, it constructs a better base for intelligent traffic system with automatic train operation and supplies a new method to analyze the reliability, availability and efficiency of the railway network.
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2001年第3期15-20,共6页
China Railway Science
基金
国家自然科学基金项目资助 (6 96 0 40 0 2 )
