利用时间约束Petri网进行项目绩效分析  

Analyzing Project Performance with Timing Constraint Petri Net

作　　者：于瑞强[1] 黄志球[1] 

机构地区：[1]南京航空航天大学信息科学与技术学院,江苏南京210016

出　　处：《小型微型计算机系统》2010年第2期276-280,共5页Journal of Chinese Computer Systems

摘　　要：时间Petri网(Time PetriNet)以及时延Petri网(Timed PetriNet)通过将时间约束引入到变迁中,广泛运用于任务调度以及性能分析,但是对于项目绩效分析所要求的关键路径、最短工期、成本分析等问题却无法有效解决.提出一种新的时间约束Petri网:将时间约束引入到库所中,在全局时钟的基础上,同时赋予Petri网的库所以延迟时间域和持续时间域两种时间约束,并且为T→P流关系的权函数赋予有色资源属性.给出时间约束Petri网的形式化定义,定义了变迁的发生规则,并引入状态类来计算状态的成本空间,给出状态类的计算方法.最后结合一个实例说明了利用时间约束Petri网进行项目的绩效分析的可行性,并用双色甘特图对时间约束Petri网的可达标识进行表述.Time Petri net and timed Petri net,in which transitions are constrained with time info,are widely used in task scheduling and performance analysis.Whereas the former only has time delaying property and the latter only has time persisting property,they can not effectively solve project performance problems,such as critical path,the shortest period and minimum-cost.A new timing constraint Petri net （TcPN for short） is proposed in which places are endued with time delaying domain and time persisting domain simultaneously.Furthermore these time constraints are based on global clock.Colored resource property is attached to backward flow relation（T→P）for cost evaluation.The formal definition for TcPN and the firing rules for transitions are furnished.An algorithm is offered to calculate the time constraint.State class method is used for the cost space analysis.For proving it is feasible to analyze project performance with TcPN,an example is provided and variant performance problems are discussed,and bi-color Gantt chart is used to depict the state space.

关 键 词：时间约束 PETRI网 成本分析 项目绩效 关键路径 状态类 

分 类 号：TP311.5[自动化与计算机技术—计算机软件与理论]