[en] CAMS (computerized accident management support) is a system that will provide assistance in case of accident in a nuclear power plant. In order to support the user in evaluating the plant state, it contains a state identification module. The state identification module provides high-level, qualitative information about the status of critical safety functions, about the availability of safety systems and about the occurrence of initiating events. This information is sent to the man-machine interface and to other CAMS modules. The state identification module is developed using a specific tool: GPS (Goal Processing System) which is based on the Goal Tree - Success Tree formalism. GPS is a tool designed to manage ''process related'' knowledge and aimed at process supervision via real-time acquisition of process variables. Fuzzy logic has been introduced in GPS in order to have smoother transitions between different states of critical safety functions and systems changes and to have a truth value associated to each piece of information provided to the user. The whole system has been tested, integrated with the rest of CAMS, on several accident scenarios. The test results are satisfactory. A brief comparison is made between the present work and previous related work at the HRP. (author)

[en] CAMS (Computerized Accident Management Support) is a system that will provide assistance to the staff in the control room, in the technical support centre, and in a national safety centre. These three groups of users do not need the same type of support. Support is offered in identification of the plant state, in assessment of the future development of the accident, and in planning of accident mitigation strategies. Last year the predictive part of the system was tested at a safety exercise arranged by the Swedish Nuclear Inspectorate, and found to be a useful tool, with potential for further development. Now, new methods are added in signal validation, state identification, tracking simulation, predictive simulation, risk monitoring, and man-machine interface design. A prototype will be demonstrated at Loen in May 1996. This prototype is still under development. The purpose of this prototype is to test those methods in a simulated environment to verify that the developed functions, using different techniques, can work together producing the desired result in an efficient way. The plan is to test these techniques at power plants. During the CAMS design, a considerable effort has been given to maintain the generality of the CAMS concept; although the referenced process has been so far a BWR nuclear plant, the use of this structure and design can be applied to other processes, including non-nuclear processes. The research programme is carried out in close cooperation with member organizations (author)