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CMPF144FUNDAMENTALS OF COMPUTING THEORY
Module 2: Abilities of Computers
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 2
Objectives
Present an overview of the abilities of computers.Present an overview on the intelligence of computersPresent the concepts of Boolean approach and their impact on computer abilitiesPresent the concepts of yes /no tree
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 3
Basic Computer Abilities
Read and write
Arithmetic
Process
Communication
Store data
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 4
Examples on using computer
Document preparation Communication Industry
Banking and Finance
Retailing
Modelling /Simulation
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 5
Computer Intelligence
Definition of IntelligenceReferring to Oxford Dictionary, Intelligent is understanding or quickness of understanding.
o Another definition:- is the computational part of the ability to
achieve goals in the world. Computer Intelligence means computer that
can be programmed to perform intelligence tasks that do not necessarily required any independent thinking.
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 6
Computer Intelligence (cont.)
Intelligence varies among people, animals and machines (computers)
People reading/learning/natural
Animals training/natural
Computers ??
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 7
How to determine the intelligence
According to De Silva, an intelligent system possesses one or more of the following characteristics and capabilities.
Sensory perception
Pattern recognition
Learning and knowledge acquisition
Inference from incomplete information
Ability to deal with unfamiliar situations
Common sense
Inductive reasoning
Inventiveness
Display of emotions
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 8
Continue..
Computer program operate using algorithms step by step to generate solutionsThe Turing Test is used as a gauge to determine whether or not an artificially intelligent being is intelligent or not. If the machine could successfully pretend to be human to a knowledgeable observer then you certainly should consider it intelligent. The Turing test is a one-sided test. A machine that passes the test should certainly be considered intelligent
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 9
Example
Develop an algorithm for a robot/computer to cross the road at the zebra crossing with traffic light
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 10
Boolean Logic
Has two values, True and False (Binary: 1 and 0, Electronic/Electrical: 5V and 0V) Three basic logics/operators;
AND,OR,NOTVenn diagrams can be used to illustrate the concepts of Boolean
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 11
Examples
The diagram below shows the documents that the information is about Apple and Banana . Some documents, the ‘A’ region, having information about Apple only, some documents, the ‘B’ region having information about Banana only, while the C region is having both information on Apple and Banana.
BC Banana
A
Apple
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 12
AND
AND means "I want only documents that contain both information on Apple and Banana."
Document that has both words ‘Apple’ and ‘Banana’ can be found under ‘C’ region.Diagram below shows the result.
BC Banana
A
AppleApple+
Banana
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 13
OR OR means "I want documents that contain either information on Apple or Banana”, either one not both. In diagram 3 below, the information can be from ‘A‘ region or ‘B’ region.
A
Apple
B
Banana
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 14
NOT
NOT means, “ I want document that contains information on Apple only, not Banana”.
In the diagram 4 below, the documents only can be found on ‘A’ region.
A
Apple Banana
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 15
Mixed Boolean operation
Boolean operators can be combined.
When combined the operators, we need to evaluate it based on order of evaluation or precedence.We can use parentheses (), in order to specify proper combination.
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 16
Continue..
Operators Order of evaluation (precedence)
() Evaluated first. If the parentheses (), are nested the expression in the innermost pair is evaluated first.If there are several pairs of parentheses “on the same level” (not nested), they are evaluated left to right.
*, / , % Evaluated second.If there are several, they are evaluated left to right.
+, -Evaluated last.If there are several, they are evaluated left to right.
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 17
Continue…
•Cats AND (Dogs OR Rabbits)
The statement in parentheses - ' Dogs OR Rabbits’ - is processed first. Followed by the rest of the sentence.
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 18
Continue..
If parentheses were omitted,
Cats AND Dogs OR Rabbits
The AND operation should process first, since based on precedence rules, the operation will start from left to right, anyway it varies among system, some will process AND first before OR. Therefore it is very important to use parentheses when we want to specify which operation should do first.
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 19
Continue…
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 20
Continue…•(Dogs OR Rabbits) NOT Cats
The statement in parentheses - 'Dogs OR Rabbits ‘- is processed first. Followed by the rest of the sentence.
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 21
Complex Logic NAND,XOR, NOR and XNOR.
•The example below is using the Boolean algebra. Two variables will be used to store the data, which are A and B, while another one variable will keep the result of the operation, determined by Q.
• Example on OR and AND operator using the Boolean algebra.
OR
If both A and B is 0, therefore the result in Q will be 0.
If either A or B is 1, therefore the result stored in Q will be 1
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 22
AND
AND
• In AND, if both A and B is having a value of 0, therefore the value stored in Q will be 0.
• If either one is having a value of 1 or 0, therefore the value in Q is still 0. The value in Q will only be 1 if both A and B having 1 as their value.
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 23
Example: OR and AND
A B Q
0
0 1 1
1 0 1
1 1 1
0 0
OR AND
0
A B Q
0 0
0 1 0
1 0 0
1 1 1
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 24
NOR
NOR - is a combination between NOT and OR. It’s simply an inversions of OR logic.If in OR, A=0,B=0 therefore Q = 0. But as inversion of OR, the result in Q will become 1.If the result in OR is 0, in NOR it will be 1, vice versa.
A B Q
0
0 1 1
1 0 1
1 1 1
00
OR
A B Q
0 0 1
0 1 0
1 0 0
1 1 0
NOR
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 25
NAND
NAND is a combination between NOT and AND logics. It is simply an inversion of AND logic. Example 1: If A = 0, B=0 , using the AND operator, Q=0. However, as NAND is an inversion of AND, the answer in Q = 1.
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 26
Example on NAND
0
A B Q
0 0
0 1 0
1 0 0
1 1 1
AND
A B Q
0 0 1
0 1 1
1 0 1
1 1 0
NAND
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 27
XOR and XNOR
• XOR - "exclusive or “- If either A OR B is 1, but NOT both, Q is 1.
• XNOR- "exclusive nor" - If A=0,B=0 or A=1,B=1, therefore Q =1.If either one of the operand is 0 or 1, NOT both, therefore Q will be 0.XNOR is an inversion of XOR.
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 28
A B Q
0 0
0 1 1
1 0 1
1 1 0
Example on XOR and XNOR
0
XOR
A B Q
0 0 1
0 1 0
1 0 0
1 1 1
XNOR
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 29
Boolean Expression.
A Boolean expression is used to construct queries that represent concepts. Boolean expressions (also known as conditions or predicates) are expressions that have two possible values - TRUE and FALSE
Example:
2 < 5 (2 is less than 5)
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 30
Continue…
Boolean expressions are also called comparison expressions, conditional expressions, and relational expressions
We can combine regular numeric, string and other expressions into Boolean conditions by comparing them to each other.
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 31
Continue…
expression < expression Less than
expression > expression Greater than
expression = expression Eventually
expression != expressionexpression <> expression
Not equals
expression <= expression Less than or equals
expression >= expression Greater than or equals
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 32
Yes/No Trees
Boolean approaches can be applied to develop a yes/no trees. The value of 1 can be represented by yes and 0 for no.
The basic idea regarding yes/no trees is to find the solutions on certain questions based on these two data, yes/no answer. The reasons is to make the students think in order to cache the right answer by provide their solution pertaining to the mention scenario.
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 33
Example:To guess the name of animal.Question: Does it have hair?Answer: yesQuestion: can it fly?Answer: noQuestion: Does it eat meat?Answer: YesQuestion: Does it have a claw?Answer: YesQuestion: Does it have a dark spots?Answer: NoQuestion: Does it have black strips and tawny color?Answer: YesQuestion: Is it tiger?Answer: Yes.
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 34
Example: Yes/No tree
Exp 1
Exp 2
Exp 2.1
Exp 2.2
Exp 3
n
y
y
n
Module 2 CMPF144 Fundamentals of Computing Theory
Slide 35
Suggested Reading
Sprankle,Maureen.(2001).Problem Solving and programming Concepts.5th ed. Prentice-HallCashman Waggoner, Shelly.(2000)Discovering Computers 2000. International Thompson Publishinghttp://www.webopedia.com/TERM/B/Boolean_expression.htmlhttp://www.shx.us/_notes/source/lang.boolean.htmlhttp://ww.ee.surrey.ac.uk/Projects/Labview/boolalgebra/http://www.lib.csubak.edu/infocomp/search/boolean/venn.htm.htmhttp://www.meadjohnson.com/products/hcp-adult-med/decision8.html