Introduction To Information Processes And Data

information processes
-collecting the process by which data is entered into or captured by a computer system, including: deciding what data is required how it is sourced how it is encoded for entry into the system
-organising the process by which data is structured into a form appropriate for the use of other information processes such as the format in which data will be represented
-analysing the process by which data is interpreted, transforming it into information
-storing and retrieving the process by which data and information is saved and accessed later
-processing a procedure that manipulates data and information
-transmitting and receiving the process that sends and receives data and information within and beyond information systems
-displaying the process that controls the format of information presented to the participant or user

the nature of data and information
-data the input to an information system
-data representation the different types of media, namely: images audio video text numbers
-information the output which has been processed by an information system for human understanding
-the generation of information from data via the information processes
-how information from one information system can be data for another information system

reasons for digital data representation
-the need for quality data, including: accuracy timeliness accessibility
-current data digitising trends, for example: newspapers on the Internet telephone system video on DVD facsimile media retrieval management

Unit	In this unit you will learn
2.1- Systems and Data	- Why computer-based information technology uses digital data, and - What the five different types of data are
2.2- Systems and Processes	- What the seven information processes are, - how the movement of data through an information system can be described and - the social and ethical issues related to information systems

Digital data

Computers are referred to as ‘digital’ systems because they can only handle data in the form of whole numbers or integers, in particular only the values 0 and 1, to represent all possible values. This is defined as binary. Binary is when the electronic circuits in computers use these two digits like switches, e.g. 1 is ON and 0 is OFF

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Every single action that a computer system performs is based around numbers that use just 1+0. A bit, short for binary digit is the smallest unit of data e.g. 0 or 1. While a byte is the smallest useful unit of data. A byte consists of 8 individual bits fused together, and can store a number from 0 to 255. This can be used to represent a keyboard character, a single measurement, a small part of an image or a video, or simply a number from 0-255. Larger quantities of data are measured using kilobytes, megabytes, gigabytes and terabytes.

Table

Unit	Relative Size
Byte	context-size
Kilobyte (KB)	= 1024 bytes
Megabyte (MB)	= 1024KB = 1 048 576 bytes
Gigabyte (GB)	= 1024MB = 1 048 576KB = 1 073 741 824
Terabyte (TB)	= 1024GB = 1 048 576MB = 1 073 741 824KB = 1 099 511 627 776 bytes

Digital technology has both its advantages and its disadvantages. One advantage is that digital (computer) technology provides us with faster and more reliable info e.g. more reliable weather forecasts and communication is now far wider spread and simpler than ever. Yet a disadvantage is that Digital (computer) technology must convert all real world data to digital data, as data from the real world is not naturally digital.

The five types of data

Data can best be describes as raw facts e.g. numbers or symbols that have no meaning or purpose by themselves.
The five divisions of data are:
1) Text data- used to represent the characteristics of the written language
2) Numerical data- used to represent pure numbers
3) Image data- used to represent picture or drawing
4) Audio data- used to represent sounds
5) Video data- used to represent images that move or change ( can also be used for animations)

Text Data

Text data represents individual symbols used in many natural and/or artificial languages. English and German are natural languages, while the languages used to program computers are artificial languages. Text is represented by numerical values and is the simplest type of data. This is because it uses a very small range of different symbols.

Numerical Data

Numerical data are easily stored as binary numbers and represent pure numbers, such as measurements and calculation results. The table below shows the first binary numbers and their decimal values.

Binary	Decimal	Binary	Decimal
00000000	0	00001000	8
00000001	1	00001001	9
00000010	2	00001010	10
00000011	3	00001011	11
00000100	4	00001100	12
00000101	5	00001101	13
00000110	6	00001110	14
00000111	7	00001111	15

When several data bytes are joined together to store a numerical value, a data structure called a ’word’ is formed. A word can store much bigger binary numbers than in a single byte. e.g. as we know 225 is the largest number stored in a byte, while 65535 is the largest number when a word of 2 bytes is used. 4 294 967 295 is the largest number when a word of 4 bytes is used.

Image Data

Image data are the most commonly used type of data. Everything displayed on a computer monitor, even text data, must be converted to image data before being displayed. An image is an electronic copy of a picture, page, scanned document or other object for display on a screen or paper. Images shown on computer monitors are made up of many tiny pixels. Pixels are the smallest controllable display element. The majority of images are stored and processed in bit maps. A bit map is a sequence of numerical values representing a sequence of pixels. An alternative method of creating images is to use objects with pre-designed shapes. This method, called vector graphics, only stores and processes data that describe each object. Vector graphics uses a few numerical values to represent an entire object, such as a line or geometric shape.

Image Data Type	Advantages	Disadvantages
Bitmapped	Allows every pixel to be processed and analyzed, Photographic images are easily processed	Every single pixel must be stored, which results in large data files. Images cannot be resized without some distortions
Vector graphic	Data describing each object are stored instead of every pixel, so data files are much smaller. Objects can be moved, edited and resized without distortions.	Color fills involving gradients and patterns are not easily handled. Photographic image data cannot be edited using vector graphs.

Audio Data

Digital audio data are a sequence of sound measurements. When audio data is recorded many measurements are made every second. Each one of these creates a digital value from the volume and the pitch of the sound. The process of digitizing creates digital values from measurements or samples or real world data.

-The below image shows a Digital waveform intimidating an Original soundwave, to such a degree that the quality would sound almost perfect to the human ears.

Video Data

Video and audio data have a great deal in common; both are a sequence of measurements. Video data are a sequence of still images recorded many times per second.
In digital video measurements are made of:
- The colour and brightness detected by individual light collection points in a digital video camera. or
-The video signal from a traditional video camera or VCR.
With Video data up to 30 frames of data mat be processed every second. Making video data the most complicated and certainly the largest of the five data types.

Displaying Data as Information

When data is shown in its raw form it can often be confusing and difficult to understand. When this data is processed into a graph, chart, map ect this helps improve the flow of into to the users.

The Seven Info Processes

The seven processes are:
1) Collecting- The collecting process gathers data from the real world environment of an information system.

2) Organizing- The organizing process prepares the data for use by the other information processes.

3) Analyzing- The analyzing process transforms data into useful information.

4) Storing and retrieving- The storing and retrieving process moves data to or from storage devices.

5) Processing- The processing process allows data to be updated, altered or edited.

6) Transmitting and receiving- The transmitting and receiving process exchanges data/information with other information systems.

7) Displaying- The displaying process presents users with the output of an information system.

Describing Processes and Data

When a new info system is being designed (or upgraded) it is important that the designers understand how data and information are used by the system. Models or diagrams of systems are used to help understand the role of the data and processes. A context diagram of an info system shows the situation or environment where it is used, the sources of its inputs and the destinations of its outputs.. Another way to describe data is in a flow diagram. A flow diagram shows how data move through an information system.
Below is an example of a Flow diagram regarding a phone call.

Social and Ethical Issues

The current computer revolution has been labeled the “ second information revolution” the first being the invention of writing. Information systems and technology have become a vital part of our lives. Although few would state that computer based info systems have not brought benefits, there are many social and ethical issues that have arisen due to computer based information systems:
Privacy and security- As communication can be shared easily among various different systems and users. This makes it very easy for private and confidential data to be misused and abused.

Access and Control- Because so much of today’s communication if achieved via computer communication systems such as the internet and telephone. Those who control these devices are in much power over the people of today. The people who control these systems can even control who uses there system and who is left out. This could divide our society into those who are “information rich” and those who are “information poor” . Major social scientists are already discussing the issue of “digital divide”— the growing gap between those who have access to computer technology and those who do not.

Employment and the changing nature of work- In our current age of information technology, those who lack the information skills will be left behind, and may be left unemployable.

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Questions/Answers

Questions	Answers
1) Why are computers referred to as ‘digital’ systems?	Computers are referred to as digital systems because they can only handle data in the form of the values 0 and 1 (whole numbers or integers),
2) How does the binary system work?	The binary system works when the electronic circuits in computers use the two digits (1 and 0) like switches, e.g. 1 is ON and 0 is OFF
3) What is the smallest useful unit of data? And how many bits dose it consist of?	A byte is the smallest useful unit of data and it is made up of 8 bits
4) List two things a Byte can represent?	A byte can represent either represent a keyboard character, a single measurement, a small part of an image or a video, or simply a number from 0-255. (any two of these are acceptable)
5) How many Gigabytes make up a Terabyte?	1024GB make up one terabyte
6) What are the 5 types of data?	The 5 types of data are,Text data,Numerical data,Image data, Audio data, and Video data
7) What is the simplest type of data?	Text data is the most simple type of data
8) How is numerical data stored? And what does it represent?	Numerical data are easily stored as binary numbers and represent pure numbers.
9) Image data on computers are made up of what? Explain?	Images shown on computer monitors are made up of many tiny pixels. Pixels are the smallest controllable display element.
10) What are the two types of image data and what are some advantages of both?	The two types of image data are Bitmapped and Vector graphic, advantages of Bitmapped is that it allows every pixel to be processed and analyzed, and photographic images are easily processed. Advantages of Vector graphic are that Data describing each object are stored instead of every pixel, so data files are much smaller. Objects can be moved, edited and resized without distortions.
11) How much frames per second can video data process?	With Video data up to 30 frames of data may be processed every second.
12) Name the seven information processes?	Collecting,Organizing,Analyzing,Storing and retrieving,Processing,Transmitting and receiving, and Displaying
13) What does the Storing and Retrieving process do?	The storing and retrieving process moves data to or from storage devices.
14) Which process presents users with the output of an information system?	The displaying process presents users with the output of an information system.
15) What can be used to show the situation or environment where the system is used, the sources of its inputs and the destinations of its outputs	A context diagram shows the situation or environment where it is used, the sources of its inputs and the destinations of its outputs
16) What does a flow diagram show?	A flow diagram shows how data move through an information system.
17) What are the 1st and the 2nd computer revolution?	1st invention of writing, 2nd current computer revolution
18) Name three social or ethical issues revolving around computer based information systems?	Privacy and security, Access and control and Employment and the changing nature of work
19) Describe how Employment and the changing nature of work is an issue revolving around computer based information systems?	In our current age of information technology, those who lack the information skills will be left behind, and may be left unemployable.
20) What is video data used to represent?	Video data is used to represent images that move or change (can also be used for animations)

page revision: 70, last edited: 04 Apr 2011 01:54

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