Process Monitoring for Safeguards Via Event Generation, Integration, and Interpretation

There is a recognized safeguards benefit from using process monitoring (PM) on nuclear facilities to complement nuclear materials accountancy. We introduce a model-based approach for PM in which the assessment regarding the state of the monitored system is conducted at a system-centric level. The proposed architecture integrates both time-driven and event-driven data integration and analysis for decision-making. While the time-driven layers of the proposed architecture encompass more traditional PM methods based on time series data and analysis, the event-driven layers encompass operation monitoring methods based on discrete event data integration and analysis. By integrating processand operation-related information and methodologies within an unified modeling and monitoring framework that includes not only current but also past plant behaviors, the task of anomaly detection is greatly improved because this decision-making approach can benefit from not only known time-series relationships among measured signals but also from known event sequence relationships among generated events. Building from the proposed system-centric PM architecture, we briefly introduce methods that can be used to implement its different components. The application of the proposed approach is then demonstrated via simulation experiements.