Methodology: The inference engine in this study operates
by the method of forward chaining. In order to execute a
rule-base expert system using the method of forward
chaining, we merely need to fire (execute) actions whenever
they appear on the action list of a rule whose conditions are
true. This involves assigning values to attributes, evaluating
conditions and checking to see if all of the conditions in a
rule are satisfied. A general algorithm of this might be: