Form 5 : Information System (IS) - 5 May 2009

Five Types of IS (5 types):
1. MANAGEMENT INFORMATION SYSTEM (MIS)
Is a set of business system designed to provide information for decision making.
2. TRANSACTION PROCESSING SYSTEM (TPS)
Is an information system that capture and processes data from day-to-day business activities.
3. DECISION SUPPORT SYSTEM (DSS)
Is a computer system that support manager in non-routine decision making task.
Involves a model, a mathematical representation of a real life situation.
4. EXECUTIVE INFORMATION SYSTEM (EIS)
Is a decision support system especially made for senior-level executive.
5. EXPERT SYSTEM (ES)/ARTIFICIAL INTELLIGENCE (AI)
ES is an information system that captures and stores the knowledge of human expert and then imitates human reasoning and decision making.
Consist two main components :
a knowledge base – is a combined subject knowledge and experiences of the human expert.
inference rules – a set of logical judgment that are applied to the knowledge base each time a user describes a situation to the expert system.
AI is the application of human intelligence to computers.
AI technology senses a person’s actions and based on logical assumptions and prior experience, take the appropriate action to complete the task.

The Usage Of Each IS :
1. MANAGEMENT INFORMATION SYSTEM (MIS)
Generate accurate timely, and organized information that can help manager make a decisions, solve problems, supervise activities and track progress.
2. TRANSACTION PROCESSING SYSTEM (TPS)
Recording a transaction such as a students registration and customer’s order.
Confirming an action or causing a response, such as printing student’s schedule.
Maintaining data, which involves adding new data, changing data or removing unwanted data.
3. DECISION SUPPORT SYSTEM (DSS)
Helps users analyze data and make decision.
Some DSS allow manager to create a model of the factor affecting a decision.
4. EXECUTIVE INFORMATION SYSTEM (EIS)
Support the strategic information needs of executive management.
Presents information such as charts and tables that show trends, ratios, and statistics.
5. EXPERT SYSTEM (ES)/ARTIFICIAL INTELLIGENCE (AI)
ES help all levels of users make decisions.
Enterprise employ expert system in a variety of roles, such as answering customer questions, training new employees, and analyzing data.

DEFINITION OF BIT, BYTE, FIELD, RECORD AND FILE :
1. BIT
A bit is a the smallest unit of data that computer can process.
Bit is a short for binary digit.
A bit is represent by the numbers 1 and 0. These numbers represent the binary system. They correspond to the states of on and off, true and false, or yes and no.

2. BYTE
Byte is a unit of information built by bits. One byte equal to 8 bits.
8 bits that are grouped together as a unit. A byte provider enough difference combinations of 0s and 1s to represent 256 individual character.
One byte represent a single character such as the number 3, letter b or a $ symbols.

3. FIELD
Combination of one or more characters.
Smallest unit of data user accesses
Field size defines the maximum number of characters a field can contain.
Field name uniquely identifies each field.
Data type specifies kind of data field contains.

4. RECORD
Group of related field
Key field or primary key uniquely identifies each record.

5. FILE
Collection of related record stored in disk.

Define Database & Database management System (DBMS):

1. Database
Is an organized collection of related data

2. Database Management System (DBMS)
Is a software that helps you organize data in way that allows fast and easy access to the data.
With a database program you can enter, modify, store, and retrieve data in a variety of ways.

List the benefit of using database :
1. Reduced Redundancy
2. Data carried in separate files, as opposed to a database, tends to repeat some of the same data over and over.
Integrated Data
3. Rather than being in separate and independent files, data in database is considered integrated because any item of data can be used to satisfy an inquiry or a report.
4. Integrity
Integrity concerns increase as the sophistication of the data increase.
5. Shared data
6. Easier access
7. Reduced development time.

Define the primary key and foreign key :

1. Primary Key
-is a field that uniquely identifies each record in a file.
-very important
Example : student ID

2. Foreign Key
-Is a second key in the table which has a primary key.
-not important

State the importance of primary key :
In normalization, primary key is used to decrease the amount of duplication.

Form 5 : Latest Programming Language

THE LATEST TYPE OF PROGRAMMING LANGUAGES

1. FIFTH GENERATION LANGUAGES

Fifth generation programming language (5GL) is an advance programming language which concentrates on solving problems using constraints given to the program.

In fifth generation language, the programmer just need to define the problem to be solve and the program will automatically code the program based on the problem definition.

Fifth generation languages are designed to make the computer solve the problem for you.
Fifth generation languages are mostly used in artificial intelligence research.
Examples of fifth generation languages include Prolog and Mercury.

2. NATURAL LANGUAGE

Natural Language programming aims to use natural language such as
English to write a program.

Instead of using a specific programming language syntax, natural language
programming will use normal English as the input to program software.

Such a technique would mean less technical programming knowledge
is required to write a program.
The programmer needs to define the program using normal language.

3. OPENGL (GRAPHIC LIBRARY)

OpenGL (Graphics Library) is a standard specification to describe the standard Application Programming Interface (API) for 3D/2D computer graphic applications.

OpenGL specification describes a set of functions and the exact behaviours that the 3D/2D application must perform.
OpenGL was developed by Silicon Graphics.

OpenGL is widely used in virtual reality, scientific visualisation, flight simulation and video game development.

Form 5 : Five Program Development Phases

In program development, there are five main phases. These phases are a series of steps that programmers undertake to build computer programs. The program development phases guide computer programmers through the development of a program.

The five main phases of program development are as follows:

PROBLEM ANALYSIS PHASE
During the problem analysis phase, the programmer will interview the client to find out what the client’s needs are.

For example, the client might be a school that wishes to set up a school registration program. So the school administrator might tell the programmer that they need to record students’ data such as name, date of birth, gender, class, parents’ names, address and contact numbers.

PROGRAM DESIGN PHASE
Based on that, the programmer will design a flow chart that represents the needs of the client, which in this case is the school registration program.

CODING PHASE
Once the flow chart is confirmed, the programmer will perform coding.

TESTING AND DEBUGGING PHASE
The school registration program will be tested by the users at the client’s site. In this case, it will be the school office administrators. If there are any errors, the programmer will do a debugging of the program.

They either show up as you type the program code, or if you have turned off the automatic syntax error check, the syntax errors show up when you try to run or compile the program.


DOCUMENTATION PHASE
After this, the programmer will complete the documentation for the program; this includes the user manual, a clear layout of the input and output records and a program listing.

Form 5 : Logical Operators, Flow Chart, Control Structure

FUNCTIONS OF LOGICAL OPERATORS

Logical operators are notations that tell the computer to perform logical operations.
Examples of Logical operation are: AND, OR, and NOT.
Logical operator compares 2 conditions and returns a TRUE or FALSE value.


AND operator
Notice that truth value of X AND Y is True ( 1 ) if only both X and Y are True ( 1 ).
Else it is false ( 0 )


OR operator
Notice that truth value of X OR Y is only True ( 1 ) if either X or Y are True ( 1 ) or both X and Y are true ( 1 )
Else it is false ( 0 )


NOT operator

The diagram shows the truth table of NOT operator NOT X is the negation of X, it is essentially the 1's complement operation.
Notice that truth value of NOT X is True
( 1 ) when X is False and vice versa.


FLOW CHART
Let’s identify some of the main elements in the flow chart. We have five main elements in a flow chart.

Flowline and arrowhead use to connect symbols and indicate the sequences of operation.
Input or output shows either an input operation (e.g. an INPUT from the
user) or an output operation (e.g. PRINT some messages).

Process shows a process to be carried out (e.g. calculation).
Decision shows a decision (or choice) to be made. The program should continue along one of two routes (e.g. if...else).

A flow chart is a diagram using symbols to show the step-by-step sequence of procedures in a program. A flow chart describes the logic and program flow of a computer program graphically.


CONTROL STRUCTURES

Control structure is a structure of statements in programming that allows
the programmer to control the flow of a program.
Control structure can be divided into sequence, selection and repetition control structures.


SEQUENCE CONTROL

Sequence control refers to the linear execution of codes within a program. In sequence control, the statements are executed one by one in consecutive order.
In sequence control, the statements are executed one by one in consecutive order.

This program will request the user’s date of birth and then request today’s date, calculate the age and finally will print the user’s age.
It will execute statement 1 followed by statement 2 and any following statements.


SELECTION CONTROL

There are times when you want your program to make a decision based on the situation given.
For example, a program that stores student’s marks may respond differently to different marks.
Or maybe a simple mathematical program will display its result as odd or even, based on the result.
Selection control enables the programmer to assign different events for different situations.

An example of selection control is “If...Then...Else” statement. The basic pseudo code for “If...Then...Else” statement is as follows.
A student requests her service hours in a library from the program, the
program will then check whether her service hours are more than/equal to 30 or not.

If the service hours are over or equal to 30, the program will print a message, “Thank you for your service”.

If the service hours are lower than 30 then the program will print a message, “Please continue to serve in the library”.

Form5 : 5.1.1 – Define Program & Programming Language

PROGRAM

A computer program is a series of organised instructions that directs a computer to perform tasks. Without programs, computers are useless.

A program is like a recipe. It contains a list of variables (called ingredients) and a list of statements (called directions) that tell the computer what to do with the variables.

Like a recipe, a program can be written in different programming languages which may express the steps differently according to the programming language syntax, but deliver the same end result.

PROGRAMMING

Programming is a creation of a set of commands or instructions which directs a computer in carrying out a task.

Later these commands or instructions will be compiled and/or interpreted and then transformed to executable instructions that a computer or electronic device can execute or run.

PROGRAMMING LANGUAGE

A programming language is a set of words, symbols and codes that enables humans to communicate with computers.

It is a language used for writing computer programs, that direct a computer to perform computation and to organise the flow of control between mechanical devices.

EXAMPLES OF PROGRAMMING LANGUAGE

Hundreds of programming languages exist today. Each language has its own standard or rules for writing the commands and/or instructions.

Examples of programming languages are:

BASIC (Beginner’s All Purpose Symbolic Instruction Code)

Pascal

C

Smalltalk.