Question Four
a. Briefly explain propositional
and predicate logic; highlight the main advantages
of predicate logic over propositionallogic.
b. Aided with an appropriate example, illustrate the use of functions in predicate
logic.
c. Given that Peter likes Mary and that John likes Mary, due to obvious jealousy,
Peter may dislike John. Write predicate logic statements
that describe these
scenarios.
d. Express the following facts in predicate calculus:
i.
Everybody likes Mary
ii.
Someone likes Mary
iii.
Football players are strong
iv.
Girls who like strong men like football players
Question Five
a. Explain the following, giving illustrative
examples and suitable mathematical
expressions where possible:
1. Deductive reasoning
2. Inductive reasoning
3. Abductive reasoning.
b. Explain the term "modus ponens", Given the following implications:
1. £1 ~ £2
: IF Patient's temperature
> 102 THEN Patient has high
temperature
2. £2 ~ £3 : IF Patient has high temperature THEN Advise two aspirin
Use modus ponens to generate a series of logical assertions
and state
transitions that will end up with £3 : "Advise two aspirin".
c. A simple expert system has three rules given below in its
forward chaining inference strategy to generate a trace that
that a patient whose temperature
is 102, has sore throat and
months has "Strep Throat". Give a step-by-step
reasoning
conclusion.
RULE
IF
AND
THEN
1
The patient has a sore throat
We suspect a bacterial infection
We believe the patient has strep throat
RULE 2
IF
The patient's temperature
THEN The patient has a fever
RULE
IF
AND
THEN
is > 100
3
The patient has been sick for over a month
The patient has fever
We suspect a bacterial infection
rule base. Use the
concludes the fact
has been sick for 2
that leads to your
Question Six
a. Differentiate between forward chaining and backward chaining inference
techniques. Give the advantages and disadvantages of each.
b. Draw the architecture of a rule-based expert system and briefly explain each
component.
c. How does a rule-based expert system relate to a production system?
d. The following rules represent the rules in a rule-based expert system. The goal
is to prove that the patient has strep throat. Using a backward chaining
inference technique, give a full trace of the steps that will help you to prove this
hypothesis; make any assumptions that help you to resolve any primitive
premises.
Rule 1
IF
There are signs of throat infection
AND There is evidence that the organism is streptococcus
THEN Patient has strep throat
Rule 2
IF
The patient's throat is red
THEN There are signs of throat infection
Rule 3
IF
The stain ofthe organism is grampus
AND The morphology of the organism is coccus
AND The good of the organism is chains
THEN There is evidence that the organism is streptococcus
km 46/48
REDEEMER'S UNIVERSITY
Lagos-Ibadan Expressway, Redemption City, Ogun State
COLLEGE OF NATURAL SCIENCES
DEPARTMENT OF MATHEMATICAL SCIENCES
SECOND SEMESTER EXAMINATIONS
2012/2013 SESSION
COURSE CODE: CMP 474
COURSE TITLE: Introduction
Systems INSTRUCTIONS: Answer any FOUR questions
TIME ALLOWED: 3 Hours
to
Expert
Question One
a. "Knowledge
is power". Justify this statement as it relates to expert system.
b. Describe "knowledge" and "domain-specific knowledge".
Why is the focus of
expert system on domain-specific knowledge?
c. Enumerate the various types of knowledge we have, briefly explain them and
give example(s) of each.
d. Explain the Object-Attribute-Value
triplets and give examples of how it can be
used to represent single attribute, multiple attribute and multiple valued facts.
Question Two
a. What is a rule? Describe the structure
of a rule in knowledge representation
and
give two illustrative examples of rules.
b. List and describe four types of rules and give an example of each.
c. Describe variable rules and illustrate how it can be used in an expert system
program.
d. Define a set of rules that are related to automobile diagnostics. At least three
rules should be written in a form that allows for inferencing.
Question Three
a. Briefly describe semantic network and write short notes on:
i.
Inheritance in semantic network
ii.
Exception handling in semantic network
b. A bird is an Animal; Canary is a bird; Tweety is a Canary; Birds have Wings;
Birds travel by Flying; Penguin is a bird; Penguin travel by Walking; Animals
breathe in Air. Using a semantic network, illustrate how these facts can be
represented.
c. Based on two (b) above, illustrate using appropriate diagram the answer that a
user gets from Tweety to the following questions: "How do you travel?".
Similarly, illustrate the answer a user gets when it queries Penguin: "How do
you travel?".
d. Create a frame structure about an automobile. The upper level class should be
AUTOS with subclasses of CARS and SUVS. Individual instances would be
specific vehicles of RUN staff. Define slots in each frame as appropriate, showing
knowledge refinement. Discuss the inheritance capability of your structure and
discuss the slot values of the instances.