关键词: 实时系统, 延迟时间Petri网（DTPN）, 验证分析

Abstract: Delay Time Petri Nets（DTPN） are an important kind of time-extended Petri nets. They overcome the difficulties of other time-extended Petri nets （such as Time Petri Nets） in the preservation of timing constraints. Schedulability verification is to testify the rationality of timing constraints of workflow model and to do simulation to verify the time accessibility for process instances. A novel verification analysis approach is presented for timing constraint workflows based on DTPN. Firstly, the definition of DTPN is given, and the time conditions of transition firable are described in combination with workflow structure. Then, the concept of DTPN firing point and the verification analysis algorithm based on this are proposed. Finally, the characteristics of DTPN are briefly analyzed. The research of DTPN enriches and improves the existing time-related Petri nets, which is of positive significance.

Key words: real-time systems, Delay Time Petri Nets（DTPN）, verification analysis