Integrated Monitoring Tasks for the Safety of Critical Systems

Systems, such as nuclear power plants, chemical processes and means of transportation, are typically seen as critical, as their failure may endanger lives and assets. The safety of such systems is, therefore, rigorously considered and established during the design and operational stages. In the design stage, an off-line safety analysis investigates, retrofits and affixes whenever necessary fault-tolerant means and reliable components. In the operational stage, the functionality of systems is monitored through three safety tasks: fault detection and diagnosis, alarm annunciation and fault controlling. However, systems still showing malfunctions and hazardous failures continue to be recorded. To address this issue, this paper develops a distributed on-line safety monitor. The monitor aims to achieve an effective integration among the delivery of the three safety tasks through the exploitation of a thorough and cost-effective off-line safety analysis model and the distributed reasoning of a multi-agent system.