The role of the goal tree—success tree model in the real-time supervision of hazardous plants

Abstract

This paper describes the basic issues involved in the development of a real-time model-based system for the supervision of complex, hazardous plant with the aim of total loss control, as carried out in the FORMENTOR project. In particular the definition of—and the constraints imposed by—the real-time requirements are presented, along with a discussion of risk prevention and its integration within a process-oriented context. Methodological guidelines to assist the development process of such a system in an industrial environment are outlined, with emphasis on quality management over the overall life cycle of the product. The essential functionalities of the system are described in turn and it is shown how a particular knowledge representation scheme, the goal tree-success tree (GTST) model, provides a basic kernel for supporting many of these functionalities. This model is presented as part of a ‘global’ approach to modelling the plant, based initially on a functionally oriented description scheme, capable of representing the dynamic aspects of complex systems which can evolve over time towards degraded and hazardous configurations. Finally, the GTST model and some of the functionalities it supports are briefly illustrated on two different FORMENTOR case studies, in the nuclear and petrochemical domains.