12 Property-based Shell, Structured-based Diagnosis
Solutions
12.1 Property-based Shell
The domain knowledge is represented by structuring the domain in objects with properties:
G
-- question : Q
-- answers : A
-- reasons : R
-- explanation : E .
The meaning is:
- G:
- Name of the object.
- Q:
- Question to the user (or a test).
- A = [ 1: A1, 2: A2... ]:
- Ai = a possible answer of the user (or the resultat of a test).
- R = [ i: Gi, j: Gj, ...]:
- Gi = a possible justification for G, if Ai applies. If i was the answer and Gi = true, then G is proven.
- R = [ G1, G2, ...]:
- G1, G2, ... are possible reasons for G, if there is no 'question' attribute Q.
- E:
- Explanation (text), if G is proven
The attributes 'question' und 'answers' are optional; the attribute 'reasons' is mandatory; the attribute 'explanation' is mandatory for proven goals.
Implement the predicate
solve( G, X) /* X is the reason for the Goal G */
according to the lecture notes. The user should be asked at most once to any question.
Solution 12.1
12.2 Structured-based Diagnosis
The predicate 'solve' from the example 12.1 can be used for struktured-based diagnosis. The inferenz proceeds from symptoms to diagnoses. The interpretation of the objects in the diagnosis realm is:
- object :
- symptom or diagnosis
- question:
- question or test (text)
- reasons:
- reasons for a symptom (simpler symptoms) or diagnoses
- explanation:
- explanation of a diagnosis (text)
Test the shell on the example of the diagnosis of a broken bike:
| Symptom | Simpler symptom or diagnosis |
|---|---|
| bike | ride (driving properties), elektric (lamp) |
| ride | wheels (difficult or clumsy riding), drive (noise), brakes |
| wheels | tires (flat), operation (unbalanced = diagnosis) |
| tires | valve (loose, missing = diagnosis), puncture = diagnose |
| operation | chain (rusty = diagnosis), gears = diagnosis |
| brakes | cable = diagnosis, brake pads = diagnosis |
| electric | lamp = diagnosis, cable = diagnosis, dynamo contact = diagnosis |
Example:
bike
-- question : 'What is the problem with your bike ?'
-- answers : [ 1 : 'driving properties', 2 : 'lamp' ]
-- reasons : [ 1: ride, 2 : electric ].
ride
-- question : ... .
flat_tire
-- reasons : [ air, valve, puncture ].
puncture
-- question: 'Is there a puncture in the tire?'
-- answers: [ 1: yes, 2: no]
-- reasons: [ 1: true]
-- explanation: 'There was puncture in the tire. Fix it.'.