离散事件系统是一类离散状态、事件驱动的动态系统，其广泛应用在信息物理系统（CPS）逻辑层的建模中。随着信息与通讯技术的不断发展，信息安全的分析与保护问题在这一类系统中的意义愈发重要。目前针对此类系统的安全防护监控器的设计方法依然存在着很多理论局限，其核心难题在于如何在多重约束条件下精确的刻画系统的信息流。本项目以离散事件系统为模型，以监督控制理论与不透明性分析为技术手段，通过采用信息状态的概念，构建新型的信息结构，从而对系统的信息不对称性、随机性以及可用性进行建模，提出新的安全防护监控器的设计方法，使得系统满足不透明性，从而保障整体系统的信息安全。一方面，改进了现有技术的诸多理论局限，为安全防护监控器的设计提供新思路和理论依据；另一方面，也为进一步拓宽了监控理论在保护实际CPS信息安全中的应用空间。

Discrete-event system (DES) is a class of dynamic systems with discrete state-spaces and event-driven dynamics. It is widely used in the modeling of high-level logic of cyber-physical systems (CPS). As the development of information and communication technologies, the importance of cyber-security has been significantly increasing. However, there are still many fundamental limitations in the design of security-enforcing supervisor for this class of system; the main challenge is how to effectively characterize the information flow of the system under multiple constraints. In this proposal, we propose to tackle this problem based on the DES model. We propose to use the supervisory control theory and the opacity analysis as the main techniques and to use the concept of information state in order to build a new type of information structure that captures the asymmetric information, the stochastic dynamic and the issue of utility; and finally, to propose a new design methodology for the synthesis of security-enforcing supervisors that enforce opacity. The results, on the one hand, will improve the current design methodologies and will provide new ideas and theoretical foundations for the design of security-enforcing supervisors; on the other hand, it will extend the application area of this theory in real world CPS.