Module
3.5
Task 9 - Expert Systems |
A.M.D.G.
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An expert system is a special computer program which
can apply hundreds of rules that it has learnt from a human expert in
a particular field of knowledge. An expert system has access to a huge
database of knowledge and can draw conclusions, make decisions and offer
expert advice based on the knowledge it has.
An expert system is made up of three parts:
1. The facts
and rules, known as the knowledge base. This is like
a giant database but it is more flexible in that it contains rules
as well as facts. It is the job of a Knowledge Engineer to
extract these facts and rules from the human experts and put them
into a form that the computer is able to understand.
2. The coding
or the program, known as the inference engine. The
program uses special languages like Prolog or LISP to search information
in its knowledge base until it reaches a conclusion. It determines
how all of the facts and rules are applied (inferencing).
The 2 types of inference are backward chaining
and forward chaining.
3. The screen
or HCI,
known as the explanatory interface. This is used
to display the answers asked by the user and to display how the system
makes its conclusions.
Expert systems are part of the larger field of Artificial Intelligence
or AI. This field of study tries to program computers with characteristics
of human intelligence, i.e. the ability to learn and make decisions
based on experience. IBM has a history of programming computers to play
and defeat the best chess players in the world.
Answer the following questions in your jotter.
1. How could
an expert system be used in the field of medicine?
2. How could
an expert system help in car mechanics?
3. Describe one
other situation where an expert system would be of assistance.
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