针对时效性指标量化难的问题，主要对时间Petri网理论模型进行了研究，结合Petri网模型时间等效变换关系，对基于**信息服务体系（MISS）的防空作战进行Petri网建模，并推导了整个作战过程的等效时延。在此基础上，利用Matlab软件，对系统的时效性能指标进行了仿真分析，验证了该方法的有效性。

It is difficult to make quantitative analysis to time efficiency of a system.This paper mainly focuses on the theoretic model of time Petri net.Based on the time equivalent transformation of Petri net model, models for the air defense combat based on the Military Information Service System (MISS) are established with the Petri net.Also, the equivalent delay of the whole operational process is derived.On this basis, analysis is made to the system time efficiency through simulation with Matlab, and the effectiveness of the method is verified.