Artificial Intelligence Lecture 44Page 4 Expert System  problem :  then number of rules may be large  control structure depend on the specific characteristic of the problrem 1) Brittleness : no general knowledge that can be used, the data is out of date 2) Lack of meta-knowledge : the limitation of the control operation for reasoning 3) Knowledge acquisition : difficult to transform the knowledge from human to machine 4) Validation : the correctness of the knowledge in the system, no formal proof that machine is better than human or human better than machine.
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