HSC IPT Notes Part 1 PDF

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HSC IPT Notes Part 1...

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Inf Informatio ormation Processes & TTechnology echnology Informa Information tion Systems What is a System? A system is a collect of parts that work together to achieve a particular purpose or result.

What is Information? • • •

Information is the meaning humans assign to data Data is transformed into information using Information Processes and Technology Knowledge is acquired when information is received

What is an Information System? An information System accepts data as an input and produces information or processed data as an output

Information Systems in Context • • • • • • •

Environment Purpose Information Technology Participants Data / Information User Information Technology

Environment • •

Everything that influences and is influenced by the Information System The circumstances and conditions that surround an Information System

Purpose •

The aim and objective of the system and the reason the system exists

Information Processes • •

What needs to be done to transform the data into useful information These actions co-ordinate and direct the system’s resources to achieve the systems purpose

Participants • •

People who carry out or initiate Information Processes within an Information System Integral part of the system during information processing

Data / Information •

Data is the raw material used by Information Processes

Users •

A person who views or uses the information output of an Information System

Information Technology •

The hardware and software used by an information system to carry out its Information Processes

Information Systems in Context Diagram

Informa Information tion Processes Information Processes • • • • • • •

Collecting Organising Analysing Storing and Retrieving Processing Transmitting and Receiving Displaying

Collecting • •

The Information Process that gathers data from the environment It includes knowing o What data is required o From where it will come o How it will be gathered

Organising •

The process that determines the format in which data will be arranged and represented in preparation for other Information Processes

Analysing • •

The process by which data is interpreted, transforming it into information Looks for patterns or meaning in data e.g. sorting student exam results to determine their ranks

Storing and Retrieving • • •

The process by which data and information is saved and then reloaded at a later time Storing is the process of copying or saving data onto a storage device Retrieving is the process of reloading previously stored data

Processing • •

The process that manipulates data by updating and editing it Processing alters the actual data present in the system

Transmitting and Receiving •

The process that transfers data and information within and between Information Processes

Displaying •

The process that outputs information from an Information System

Example of an Informa nformation tion System RTA (RMS) holding information on vehicles and drivers

Environment • • • • •

All drivers, driving instructors and driving examiners Vehicle owners and Vehicle inspectors RTA services like registration and licensing Flow of information between RTA and Department of Transport The police and courts

Purpose •

Managing the registration of all drivers and motor vehicles

Data / Information • • • •

Driver details & payment details Driver license number, driving history, license type and classification Vehicle owner details, registration number and payment details Vehicle inspection records and insurance details

Participants • • • • •

Data entry operators Inspectors Counter staff Admission officers at RTA Offices, motor registries and vehicle inspection station Police department Traffic branch (driving records and vehicle history)

Processes •

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•

•

•

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Data Collecting from: o Registration application forms o License applications o Renewals o Vehicle inspection o Driving tests results Data organised and stored into databases with information on: o Drivers o Vehicle information o Finances Data processing when o Registering Vehicles o Renewing licenses Data analyzing produces statistics on: o Registered vehicles o Licensed drivers Transmitting data on vehicles and drivers to: o Police o Other required authorities Displaying information on: o Screens and as reports / printouts

Information Technology • • • • •

Computers EFTPOS machines for making payments Bar code scanners for registration notice payments Networking for computers Driver licensing and vehicle registration software

The Nature of Data and Informat Information ion • • •

Data – Raw material or input for an information system Seven information processes work on input data to transform it into information Information – the output from an Information System that is both meaningful and understandable

• • •

Information coming out of one Information System can be used as input to another Information System Data used by an Information System is of various types Types of data used by Information Systems: o Text o Numbers o Images o Audio o Video

Text • •

Text media is used to represent characters Can be printable characters (e.g. Alphabet) or non-printable (carriage return/tab)

Numbers •

Is used to represent integers, real numbers (decimals), currency and date/time

Images • • •

• •

Is used to represent data as visual information Is an electronic copy of a picture, page, scanned document or other objects for display on a screen or a piece of paper There are two ways to represent images o Bit maps o Vector graphics In a bit map the data describes the colour and brightness in every single pixel Vector graphics uses a few numerical values to represent an entire object such as a line or geometric shapes.

Audio • • •

Is used to represent sounds Audio data measures the volume and pitch of a sound Digitising creates digital value from measurements or samples of real world data

Video •

Video data are a sequence of still images recorded many times a second

Unprocessed Data John, HR7 Abrahamson, 17, 23 52, 15 Processing this data might be done by organising it into a sentence.

“John Abrahamson is 17. He is in HR7 and gained assessment marks of 23 and 52 on his last two tasks. He is ranked 15th in his group.” This processed data is called information. It has been interpreted and made meaningful by the user. Information from one information system can be the data for another system. Example: The Australian Census System •

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Information is collect every five years e.g. age, jobs, children, income, cultural and religious interests and residence location Information used by the Government for future planning

Digital Repr epresentation esentation of Data Advantages of Digital Data •

Easy to store E.g. CD vs Hard Copy of Encyclopedia

• • • • •

Easy to manipulate e.g. sort and search Easy to transmit Cheap to handle Easy to keep up to data Fast to process

Disadvantages of Digital Data • • • • •

Must be backed up to avoid loss Copyright and Privacy Access to technology for all Ongoing cost of hardware and software updates Training of personnel involved in working with data

ASCII • •

Stands for American Standard Code for Information Interchange Is a character encoding scheme to represent text in computers

Decimal to Binary Conversion • • •

‘A’ has an ASCII value of 65 Convert 65 to binary to represent ‘A’

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6510 = 010000012

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Convert the following numbers into binary

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9610 = 011000002

Binary to Decimal •

Convert 110102 to Decimal

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110102 = 1*16 + 1*8 + 1*2 = 2610

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Convert the following binary number into decimal 100112 = 1*16 +1*2 +1*1 = 19

Digitising Trends Social and Ethical Issues • • • • • • •

Privacy of the Individuals Security of Data and Information Accuracy of Data and Information Changing Nature of Work Appropriate Information Use Health and Safety Copyright Laws

Privacy of the Individual • •

Privacy includes the right of people not to give others their personal data Information technology puts pressure on us to destroy this right e.g. cookies

Data Security Issues • • • • • •

Virus attacks Hacking – Deliberate unauthorised accessing of data from a secured data source Theft Unauthorised Access Hardware faults Software faults

Commonly Used Strategies • • • • • •

Passwords Backup copies Physical barriers Anti-virus Software Firewalls Data encryption

•

Audit Trails

Accuracy of Data and Information • •

Data stored in information systems need to be accurate, consistent and up to date. This is known as Data Integrity Sometimes inaccurate data is deliberate, but most times it is an accident

Data Validation • • •

Programs can validate data entry to some extent If only numeric data is required then the program can notify users when the wrong type of data is entered However, this doesn’t guarantee the accuracy of the numeric data

The Changing Nature of Work • • • •

Information technology has changed the nature of work Nowadays while working, we are less likely to be involved in repetitive, boring and dangerous activities than we were in the past Most jobs now involve computers in some way and some jobs have actually now been replaced by computer procedures Other jobs have changed significantly

Health and Safety • •

Ergonomics is “fitting work to people”, that is, the design or arrangement of workplaces, products and systems so that they fit the people who use them. The science of ergonomics looks at ways of adapting tools, implements and working environments to reduce stress on the worker and to increase efficiency

Appropriate Information Use • •

Laws are only able to protect information systems to a limited extent Much of the use of information system comes down to our value system, both as individuals and as members of our society

Copy Right Laws • •

Copyright is the legal protection given to the original expression of ideas, including information systems Copyright generally starts from the time the Information System is completed

Tools for Informati nformation on Processes Information Processes • • • • • •

Collecting Organising Analysing Storing and Retrieving Processing Transmitting and Receiving

•

Displaying

Collect Collecting ing The process by which data is captured or entered into a computer system, including • • •

Deciding what data is required How it is sourced How it is encoded for entry into the system

Comput Computer er and No Non n-comput computer er tools Data can be collected using both computer and non-computer tools Computer Tools – Hardware and Software tools can be used for collecting data •

Hardware used for collection o Scanners and/or digital cameras to collect images o Microphones and/or recording from peripheral devices to collect audio o Video cameras and/or peripheral devices with appropriate interfaces to capture video o Keyboards and/or optical character readers to collect numbers and text o Data capture devices such as counters for counting cars on a road

Scanners Scanners are optical devices that with the relevant software, captures text and images and convert them into digital data. e.g. Hand held, flathead, overhead scanners and barcode readers

Digital Cameras • •

Used to collect still or moving images The amount of detail that the camera can collect is called the resolution and is measured in pixels

Microphones • • •

Sound travels through the air in waves; It is analog data. Digital audio is sound that has been digitised Microphones allow sound to be stored in the computer where it can be manipulated and replayed

Equity for Users Together with soundcards and speakers it has allowed people with disabilities to have an opportunity to us the computer

Keyboards • •

The most common input device There are different types of keyboards

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The most common keyboards are the QWERTY keyboard

OCR – Optical Character Recognition • •

Used to collect text and numbers Matches characters with characters stored in application programs

Other data capture devices • •

Pointing devices such as a mouse, trackball, graphics tablet, joystick and light pen Sensors such as pressure, temperature, weight, speed and atmospheric humidity

Historical and Emerging Trends • • •

One of the earliest methods of collect was punch cards Touch screens are a more current development and used in a variety of areas Smart cards are an input device of the future

Image

Soft Softwar ware used for collec ollection tion Software Instructions that control the hardware and direct its operation Software used for collection • • •

Device drivers that allow hardware to interface with the operating system Software that allows participants to enter or import data Software that allows participants to transfer data between computers e.g. Internet

Device Driver •

A program that provides the interface between the operating system and a peripheral device

Data Entry into Application Software •

Application Software

• • • • • •

• • • • •

A software that performs a specific set of tasks to solve specific types of problems e.g. Microsoft Word & Microsoft Office Software applications collect data using the keyboard, mouse and data entry forms Data entry screens aim to collect accurate data Data Integrity Occurs when data is correct and accurately reflects its source Ongoing process where new and existing data is check for accuracy Integrity of collected data is accomplished using data validation and data validation checks Data validation A check at that time of data collection to ensure that data is reasonable and meets certain criteria Data Verification A check to ensure that the data collected matches sources of the data More difficult than data validation Valid data does not mean accurate data When collecting data, user interfaces displays information to users to guide them through the collecting process User interfaces should be user friendly and easy to use

The Internet as a collection source • • • •

Internet is a medium used to transfer data/information between computers Uses protocols like HTTP/TCP/IP Web browsers used to locate and access web pages Data entry web pages collect data from users visiting the website

Non-computer procedures in collecting •

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Literature searches Involves location information from all published works in both electronic and hard copy forms Surveys and interviews Conduct to collect data from people using structure or unstructured questions Form design for data collection General instructions should be clear for all the questions since paper based forms don’t react to user responses Manual Recording of Events e.g. courier delivering parcels recording delivery and receivers signature Existing Non-Computer Data Records from before the advent of computer technology

Social and Ethical Issues in Collecting • • •

Bias with the collection process Accuracy of collected data Failure to acknowledge the source of data

• •

Privacy concerns of individuals Ergonomics for data entry participants

Bias within the collection process • • • •

Bias is an inclination or preference towards an outcome Bias during data collection leads to inaccurate data leading to inaccurate outputs Incomplete data can be misleading e.g. Income Bias can be deliberate or accidental(due to misunderstanding of the question)

Inaccuracy of Collected Data • •

The value of an information system depends on the accuracy of the data it collects Data collection tools should be tested before being put into use e.g. data entry devices, forms and surveys

Failure to acknowledge the data source Important reasons for acknowledging the data source • • •

Justification of the output Results from surveys are accepted only if the source of data is accurate Providing mechanisms for tracking and auditing data If source of data is unknown it is difficult to determine the accuracy Requirements of the source organisation When providing previously collected data sources may ask to be acknowledged

Privacy • • • • •

Data collection often involves accessing personal and private data Data collection can happen without their knowledge People have no control over how the data will be used ‘Codes of Practice’ have been introduced to protect data privacy of individuals Mostly these codes are voluntary and organisations are not required to follow them

Some privacy principles • • •

People you collect the personal data from must be told how the data will be used Personal data must not be used for any purpose other than those stated when they were collecting People have the right to inspect and correct any data collected from them

The ergonomics of collecting data • • •

Ergonomics is the study of human factors involved in the design of the workplace A well-designed work environment is safer and more productive e.g. data entry operators Creating an ergonomic environment is expensive but less expensive than the cost of time lost due to illness and work injuries, and claims for workers compensation

Factors to be considered in ergonomics • • • •

Design of Furniture e.g. chairs, desks, keyboards and the mice Placement of Equipment e.g. Keyboard, mouse and monitor Techniques used at the keyboard e.g. wrist rests, placement of hands and typing techniques Operator work routine

Factors to be considered in Ergonomics • •

Total work environment e.g. lighting, noise and temperature Design of software e.g. Ease of use, screen readability and help facilities

Organisin Organisingg Organising is the process of arranging, representing and formatting data for use by other information processes.

Data is organized using both: • •

Hardware Software

Hardware is used to digitise and organise the data. Data can be represented digitally •

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Text o Characters, numbers, letters and symbols use a standard method of conversion such as ASCII or EBCDIC Images o Images are divided into dots called pixels o A number of bits are assigned to each pixel

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o The relationship between the images and the bits in memory is called bitmapping Audio o Is achieved through a process called sampling o The quality of the sound is dependent on the sampling size as well as the sampling rate

Decimal to Hexadecimal Conversions • •

The hexadecimal number system use...