Again classroom presentation March 2012.

1. Expert System
Presented by:
Mukul, Pankaj & Divya

2. Expert System: Meaning
 An expert system is a computer system
that competes with the decision-making
ability of a human expert.
 Designed to solve complex problems by
reasoning about knowledge, like an
expert, and not by following the
procedure of a developer as is the case
in conventional programming.

3. Meaning Continued
 It is a computer program that represents and
reasons with knowledge of some specialist
subject with a view to solving problems or
giving advice
 It is divided into two parts.
 Fixed, independent of the expert system: the
inference engine.
 Variable: the knowledge base.
 Conversational: A dialog interface to
communicate with users.

4. Software architecture
 The rule base or knowledge base
 In expert system technology, the
knowledge base is expressed with natural
language rules IF ... THEN ...
 For examples :"IF it is living THEN it is mortal"
 "IF his age = known THEN his year of birth =
date of today - his age in years.

5. The inference engine
 The inference engine is a computer
program designed to produce a
reasoning on rules.
 In order to produce a reasoning, it is
based on logic.
 With logic, the engine is able to generate
new information from the knowledge
contained in the rule base and data to
be processed.

6. Advantages
 Evolving an expert system is to add, modify or
delete rules. Since the rules are written in plain
language, it is easy to identify those to be
removed or modified.
 Quick availability and opportunity to program
itself.
 The reliability of an expert system is the same
as the reliability of a database, i.e.
good, higher than that of a classical program.

7. Disadvantages
 Knowledge collection and interpretation into
rules, the knowledge engineering.
 Expert knowledge is not well understood:
there is a lack of rules, rules are
contradictory, and some are poorly written
and unusable.
 Expert systems most often use an engine
incapable of reasoning. Therefore, oftentimes
the expert system works poorly and the
project is abandoned

8. On a lighter side

9. Application field
 Highly interactive or conversational
applications, IVR, voice server.
 Fault diagnosis, medical diagnosis
 Decision support in complex
systems, process control, interactive user
guide.
 Educational and tutorial software.
 Logic simulation of machines or systems
 Knowledge management.
 Constantly changing software.

10. Thank You
 IF= Nerds are bad, THEN = Politicians
are… error !