Q: why is SSCFI expert system model-based? Why is the model central to this expert system?
* according to published data, the largest body of this expert-system’s “knowledge” is about line records, even though the expert-system’s main job is something else ie diagnosis! This is common among real world expert-systems.
* I guess among expert systems, model-based designs form one well-known type. A one-liner introduction is “An expert system based on fundamental knowledge of the design and function of an object. Such systems are used to diagnose equipment problems, for example.”
* Circuit models help the system survive and continue to function despite 2 difficulties
1) many line records are unreliable — non-standard
2) many test equipments (used to test circuits) are unreliable — often misconfigured
Most if not all of the arguments below are my hypotheses with limited evidence.
* I feel an intelligent expert system can “reason” and use judgement, just like humans do with an internal model. The more comprehensive the model, the more it can reason and make sense of confusing data.
* I feel Fault-isolation may require the system to keep track of test resutls, to be interpreted in context. Circuit model is part of the context.
* I feel test data are perhaps correlated. The relations can be hard to identify. A model helps. A human tester, too, relies on a circuit model to correclate data.
* I feel Test results have patterns, as experienced human testers know. Perhaps patterns about brands and models, about seasons, about circuit types and designs … These could presumably be incorporated into the circuit model