中文摘要：

运用Petri网对实际系统进行建模时，事件的发生往往必须在一个时间区间序列内。针对此问题，提出一种离散时间区间Petri网模型。着重对模型的可达性进行了分析，给出模型的合法变迁序列判定算法，并在此基础上提出模型的状态可达性判定算法。通过实例分析，验证了所提的离散时间区间Petri网模型的可行性和有效性，该模型可用于工作流分析、业务过程建模等领域，能够进一步增强Petri网对离散事件系统的模拟与分析能力。

英文摘要：

In the modeling of real system by using Petri net, the implementation of event must be in a series time span sometimes. To deal with this problem, a Discrete Time Span Petri Net（DTSPN） based on time Petri net was proposed. Model＇s attainability was analyzed with great emphasis, and the algorithm of distinguishing model＇s valid transaction sequence was given. On this basis, a new algorithm about state attainability aimed at DTSPN was proposed. By the analysis of example, the proposed DTSPN model was feasible and valid. It could be applied in workflow analysis and business process modeling, and the simulated and analyzing capability of Petri net could also be improved.