EXPERT SYSTEM
RAKESH KUMAR BACHCHAN
CDCSIT, T.U.
EXPERT SYSTEM
•
Expert system is a computer program that contains some
of the subject-specific knowledge of one or more human
experts.
•
It simulates the decision-making process of a human expert
in a specific domain.
•
An expert systems are meant to solve real problems which
normally would require a specialized human expert (such
as a doctor or a minerologist)
EXPERT SYSTEM Contd..
•
Block Diagram
Expert System Shell
Explanation
sub system
user
interface
User
Inference
Engine
Case
specific
Data
Knowledge
base
Knowledge
base editor
Block Diagram of Expert System
EXPERT SYSTEM
•
User interface
•
•
The user interacts with the system through a
which may use menus, natural language or any other style of
interaction).
Inference engine
•
Used to reason with both the
from expert) and data specific to the particular problem
being solved.
•
The expert knowledge will typically be in the form of a set of
IF-THEN rules.
EXPERT SYSTEM
•
Case specific data
•
•
Explanation subsystem
•
•
Includes both data provided by the user and partial
conclusions (along with certainty measures) based on this
data.
Allows the program to explain its reasoning to the user.
Knowledge base editor
•
Help the expert or
check the knowledge bas
EXPERT SYSTEM
•
Knowledge base
•
component of an expert system that contains the
system’s knowledge is called its knowledge bas
•
contains declarative and procedural knowledge
•
Declarative knowledge:
situation.
•
Procedural Knowledge:
action
EXPERT SYSTEM
Identification
Conceptualization
Formalization
Testing
Implementation
•
Development of Expert system
•
Identification
Fig: Stages of expert system development
•
It refers to the identification of the problem precisely
•
Exact nature of the problem should be identified
•
goals should also be stated
EXPERT SYSTEM
•
Development of Expert system
•
Conceptualization
•
•
During this the knowledge engineer frequently creates
diagram of the problem to depict graphically the relationship
between the object and processes in the problem domain.
•
Problem may also be divided into the subproblem if
necessary
During Identification and Conceptualization the focus is
completely on understanding the problem.
EXPERT SYSTEM
•
Development of Expert system
•
Formalization
•
•
During this the problem is connected to its proposed
solution, an expert system, by analysing the
relationship depicted in the above stage.
Implementation
•
F
computer that has been chosen for system development
EXPERT SYSTEM
•
Development of Expert system
•
Testing
•
Testing is done to ensure that the system is as per the
requirement. If it does not provides effective result
then the system should be restructured.
FEATURES
•
What are the features of Expert System?
•
The program should be
developed to meet a specific need, one for which it is
recognized that assistance is neede
•
The program should be
designed so that even a novice computer user finds it easy to
use
•
The program should be
expert system may be used by non-experts, who should be able
to increase their own expertise by using the system
FEATURES
•
The program should be able to
able to explain the reasoning process that led it to its conclusions, to allow us
to decide whether to accept the system’s recommendations
•
The program should be able to
with different levels of knowledge may use the system, an expert system
should be able to answer questions about points that may not be clear to all
users
•
The program should be able to
expert system be able to respond to our questions, it also should be able to ask
questions to gain additional information
•
The program’s knowledge should be
should be able to revise the knowledge base of an expert system easily to
correct errors or add new information
Homework
•
Describe the role of Expert, Knowledge Engineer and
programmer in the development of expert system?
Thanks