Assignment 1

Date set: 10th February 2023

Submission date due: 5:00PM on 10th March 2023

Feedback date due: 31st March 2023

This assignment carries 40% of the coursework marks for this module. The submitted file has to be named by the first half ofyour University email address and should be uploaded to the  Assignment- 1 folder in Blackboard by 5:00PM on the due date.

1. Use the depth-first search algorithm to traverse the following graph and record the details

of “open” and “close” at each step.

(20 marks)

2. The following rule base is used to classify fruits according to their characteristics.

Rule 1:  If Shape = long and

Colour=green or yellow

Then Fruit = banana

Rule 2:  If  Shape = round or oblong and Diameter > 4 inches

Then Fruitclass = vine

Rule 3:  If  Shape = round and

Diameter < 4 inches

Then Fruitclass = tree

Rule 4:  If  Seedcount = 1

Then Seedclass= stonefruit

Rule 5:  If  Seedcount > 1

Then Seedclass=multiple

Rule 6:  If Fruitclass = vine and

Colour = green

Then Fruit = watermelon

Rule 7:  If Fruitclass = vine and

Surface = smooth and

Colour = yellow

Then Fruit = honeydew

Rule 8:  If Fruitclass = vine and

Surface = rough and

Colour = tan

Then Fruit = canteloupe

Rule 9:  If Fruitclass = tree and

Colour= orange and

Seedclass= Stonefruit

Then Fruit = apricot

Rule 10: If Fruitclass = tree and

Colour = orange and

Seedclass = multiple

Then Fruit = orange

Rule 11: If Fruitclass = tree and

Colour = red and

Seedclass = stonefruit

ThenFruit = cherry

Rule 12: If Fruitclass = tree and

Colour = orange and

Seedclass = stonefruit

ThenFruit = peach

Rule 13: If Fruitclass = tree and               colour = red or yellow or green and Seedclass = multiple           ThenFruit = apple

Rule 14: If Fruitclass = tree and

Colour = purple and

Seedclass = stonefruit

ThenFruit = plum

a) Initially the Knowledge Base (KB) consists of the above rules and the following facts in the working memory

Diameter = 1 inch, Shape = round, Seedcount = 1, Colour = red

Show how, by using the forward chaining algorithm (Data Driven), a KBS would arrive at a decision. Detail a trace of the execution of the algorithm in the form of the table shown below:

where:

•  Execution Cycle counts the number of recognised action processes

•  Applicable Rules indicates the rules which could be considered for firing

•  Selected Rule shows the number of the rule chosen for firing (use the first available rule as the conflict resolution policy)

•  Working Memory shows the facts used by the KBS (10 marks)

b) Given a single goal Fruit, and some possible answers provided by a user when relevant    questions are asked: Diameter = 1 inch, Shape = round, Colour = red, and Seedcount = 1.   Show how, by using the backward chaining (Goal Driven) inference algorithm, a KBS would prove the initial goal Fruit.

Trace the execution of the KBS in the form:

where:

•  Goal is the goal/sub goal under investigation at a particular stage in the reasoning process

•  Applicable Rules indicates those rules which could fire at any particular time