R.R. Bakker

Issues in practical model-based diagnosis

The model-based diagnosis project at the University of Twente has been directed at improving the practical usefulness of model-based diagnosis. In cooperation with industrial partners, the research addressed the modeling problem and the efficiency problem in model-based reasoning. Main results of this research are that (1) re-use of electronically available descriptions of systems for diagnostic purposes is possible, and (2) efficient reasoning can be realized using PDE, hierarchic models, and a simple diagnostic strategy. We have built a prototype diagnostic system which shows the technical feasibility of model-based diagnosis in a computer system. The project was concluded in July 1993 by the development of the `Diagnostic Toolbox?. The Diagnostic Toolbox supports the modeling of technical systems for diagnostic purposes, and it contains several model-based reasoning methods.

Reusing design information for model-based diagnosis

Model-based diagnosis (MBD) is a technique to locate faults in a system with the aid of a model of that system. The model describes the correct behavior of the system, and possibly also the behavior in case of a fault. In the field of model-based diagnosis, most attention has been given to the problem of reasoning: how to derive diagnoses, given a model. When applying MBD in practice, modeling appears to be a problem of equal magnitude. In this paper, we analyze the modeling process, and show how design information can be used in this process. We investigated the use of information in two standard languages for information interchange: EDIF and VHDL. We expect that the results from this research carry over to other design formats.