Expert system

1. Prepared by:- Fikirte Getachew
Hayat Yassin
Submitted to :- Dr. Million

2.  What is an Expert System?
 Overview of expert systems.
 Components of expert systems
 Knowledge Base
 Reasoning (inference engine)
 User interface
 Interpreter
 blackboard
 Building Expert System
 Designing of initial Knowledge base
 Types of Expert System (ES)
 When to use an expert system
 Advantage of ES
 Limitation of ES
 Expert control system
 Two main types of expert control system
 Tasks of expert control system
 Conclusion
 Recommendation

3.  Experts are people who are very familiar with
solving specific types of problems.
 An expert system is an intelligent system that
can perform special and difficult tasks in some
fields at the level of human experts.
 There are several major application areas of
expert system such as agriculture, education,
environment, law manufacturing, medicine
power systems etc.

4.  Can….
explain their reasoning or suggested decisions
Display intelligent behavior
Draw conclusions from complex relationships
Provide portable knowledge
 Expert system shell is collection of software
packages and tools used to develop export
systems.

5.  Every expert system consist of;
a) Knowledge base
b) Reasoning or inference
c) User Interface
d) Interpreter
e) blackboard

6.  It is expert systems contain both factual and
heuristic knowledge.
 Factual knowledge is that knowledge of task
domain that is widely shared, typically found in
textbooks or journals.
 Heuristic knowledge is less exhaustive, more
experiential, more judgmental knowledge of
performance.

7.  Two methods of reasoning when using
inference rules;
I. Backward Chaining: it starts with list of goals
and works backward if there is data which will
allow it to conclude these goals.
II. Forward chaining: it starts with data available
and then concludes a desired goal.

8.  To communicate between the user and the
expert system.
 The user interacts with the expert system in
problem-oriented language such us In
restricted English, graphics or a structure
editor. The interface mediates information
exchanges between the expert system and
human user.

9.  Through the user interface, interpreter explains
user questions, commands and other
information generated by the expert system,
including answers to questions, explanations
and justifications for its behavior, and requests
for data.

10.  To record intermediate hypothesis and
decisions that the expert system manipulates.

11.  The key for successfully building an expert
system is to begin it from a smaller one, and
extend and test it step by step, make it into a
larger scale and more perfect system.
 The general procedure for building Ess;
 Design of initial knowledge base
 Development & test for prototype system
 Improvement & induction for the knowledge.

12.  Problem identification
 Knowledge conceptualization
 Concept formulization
 Rule formulation
 Rule validation

13. CATEGORY PROBLEM ADDRESSED
 Interpretation
 Prediction
 Diagnosis
 Design
 Planning
 Monitoring
 Debugging
 Repair
 Instruction
 Control
 Inferring situation description from
sensor data
 Inferring likely consequences of give
situation
 Inferring system malfunction from
observation
 Configuring objects under constrains
 Designing actions
 Comparing observation to plan
vulnerabilities
 Providing incremental solutions for
complex problems
 Executing a plan to administer a
prescribed remedy
 Diagnosing, assessing and repairing
student behavior
 Interpreting, predicting, repairing
and monitoring system behavior

14.  Provide a high potential payoff or significantly
reduced downside risk
 Capture and preserve irreplaceable human
expertise
 Provide expertise needed at a number of
locations at the same time or in a hostile
environment that is dangerous to human health

15.  Provide expertise that is expensive or rare
 Develop a solution faster than human experts
can
 Provide expertise needed for training and
development to share the wisdom of human
experts with a large number of people.

16.  CONSISTENT: It provides consistent answer
for repetitive decisions, processes and tasks
 MAINTAINS: it holds and maintain levels of
information.
 CLARIFY: it clarify the logic of decision
making.
 NO HUMAN NEED: it cannot need human, it
works continuously.
 MULTIUSER: a multi user expert system can
serve more users at a time

17.  SENSE: it lacks common sense needed in
decision making.
 CREATIVENESS: it cannot respond creatively
like a human expert would in unusual
circumstances.
 ERRORS: in knowledge base errors may occur
and this leads wrong decisions
 ENVIRONMENTS: if knowledge base is
changed it cannot adapt changing
environments

18.  Important differences between expert systems
and expert control systems:
 Expert systems simply complete consultative
function for problems of special domains and
old users to work.
Expert control systems need to make decisions
to control action independently and
automatically.
 Expert systems usually works in off-line mode.
Expert control system need to acquire dynamic
information in on-line mode and make real-time
control for the system.

19.  Expert control system
with a more complex structure, higher cost,
better performance, and used to plants or
processes where higher technical requirements
are needed.
 Expert controller
with a simpler structure, lower cost and has a
performance that can meet the general
requirements for the industrial process control.

20.  The expert control system should execute the
following tasks;
 Supervise the operation of the plant (process) and
controller.
 Examine possible failure or fault of the system
components, replace these faulty components or
revise control algorithms to keep the necessary
performance of the system.
 In special cases, select suitable control algorithm to
adapt the variation of the system parameters and
environment.

21.  Important differences between expert systems
and expert control systems:
 Expert systems simply complete consultative
function for problems of special domains and
old users to work.
Expert control systems need to make decisions
to control action independently and
automatically.
 Expert systems usually works in off-line mode.
Expert control system need to acquire dynamic
information in on-line mode and make real-time
control for the system.

22.  In summary, Expert systems are intelligent
computer system that perform special or
difficult tasks at the level of human experts.
They are made up of a knowledge base
(information storage),reasoning base
(inference engine), user interface, interpreter
and black board.
 Expert systems are classified based on their
functions such as Interpretation, Prediction,
Diagnosis, Design, Planning, etc.

23.  For a developing country such as ours, utilizing
and implementing expert systems in different
fields would not only benefit the industries that
use them but also the country as a whole.
Advanced development in areas such as
agriculture, education, environment, medicine
etc. by the use of expert systems would
certainly improve the social and economic
conditions of its surroundings.