A web-based fault diagnostic maintenance system for steam turbines based on domain ontology and expert system

This paper describes the design of a fault diagnostic maintenance system for steam turbines based on a domain ontology of the turbine and coupled to an expert system. The main data and information constituting the system come from disparate data bases with different usage. In this case a database for equipment characteristics and another containing maintenance acts defining symptoms, defects and remedies for maintenance cases. An expert system (ES) integrated with the domain ontology of the steam turbine is used as a reasoner in order to generate new knowledge. The philosophy of such an approach consists on one hand, in the capitalisation of all the knowledge gathered from both databases and integrated into a single ontology creating relationships between classes. On the other hand, the ES represent a powerful tool in order to exploit the ontological representation for aided diagnostic and maintenance. The final system must be independent from any ontology editor such as Protege, as well as a specific expert system shell that may limit its online use.