This paper investigates the problem of the existing information system security situation assessment models that are less concerned about fuzzy factors and lack of reasoning. First, Pythagorean fuzzy sets are adopted to deal with the ambiguity and uncertainty of the civil aviation airport security inspection information system security situation indicators, and a Pythagorean fuzzy Petri nets (PFPNs) model is established according to the indicator system. Then, based on the characteristics of PFPN, the propositions credibility reasoning algorithm and the security situation fuzzy reasoning algorithm are designed. Finally, the feasibility of the model is verified through the assessment experiment on the security inspection information system of a civil aviation airport. The experimental results show that the PFPN model has better stability and lower algorithm time complexity compared with other models.

中文翻译：

---

基于毕达哥拉斯模糊Petri网的民航机场安全检查信息系统安全评估模型

本文研究了现有的信息系统安全状况评估模型存在的问题，该模型较少关注模糊因素且缺乏推理。首先，采用毕达哥拉斯模糊集处理民航机场安全检查信息系统安全状况指标的歧义和不确定性，并根据该指标体系建立毕达哥拉斯模糊Petri网模型。然后，根据PFPN的特点，设计了命题可信度推理算法和安全态势模糊推理算法。最后，通过对民航机场安检信息系统的评估实验，验证了该模型的可行性。