Computer Studies
Applications of Computers and their social and economic implications
Be aware of the following for each type of application of computers:
The purpose of the application.
The required outcome.
The overall system design, including both the computerised and the non-computerised parts of the application.
The necessary inputs to the system and the means by which any data is captured.
The overall organisation and processing of the data within the system.
The use and organisation of the major software and hardware components of the system.
The need for recovery in the event of a system failure.
The interface between the system and its users.
The effectiveness of the system in practice.
The effects of the application on individuals and organisations.
Communication And Information Systems
Data is exchanged between computers. The data can be in the form of text, images, sound or video.
Electronic mail (e-mail) simple message exchange. Can attach other files
Electronic conferencing can either be a text, voice or video conference
On-Line Services & Remote Databases
Computers are often placed in locations where the public can use them to lookup information.
Information retrieval: online databases, encyclopaedias, dictionaries, bus timetables, etc.
Library systems: documents are stored digitally where they can be searched
Multimedia systems: stored information contains text, sound, video, etc.
Commercial And General Data Processing
These are often batch-processing systems involving data being collected over a period of time, and then processed later. The collected data is stored in a transaction file, and this is used to update the master file to give a new master file.
Banking systems: bank accounts are updated based on daily transactions
Personnel records: employee's pay is calculated based on hours worked
Stock control: when items are sent / received, the stock is updated
Order processing: received orders are dealt with
Industrial, Technical And Scientific Uses
Data is entered into the computer and the computer can then manipulate the data. In the case of CAD systems, products can be designed and tested completely within the computer's memory. In forecasting systems, predictions are made about the future based on previous data, and a model of how the system works.
Weather Forecasting: try to predict weather, taking data from sensors, using computer models of weather systems
Computer-aided design (CAD): designs for objects can be designed, altered and tested within the computer, prior to manufacture
Monitoring And Control Systems
A computer is used to monitor a system through the use of sensors (such as light, heat, etc.) The computer can then operate devices to control the system (such as pumps, valves, etc.)
Monitoring hospital patients: checks heart rate and sets of alarm if low
Nuclear power station control: monitors temperature and adjusts coolant
Traffic survey and control: checks number of cars, alter traffic light timing
Automation And Robotics
The use of computers to control other mechanical devices. Usually requires some sort of interface which allows the computer to receive data from input sensors, and to control output devices such as motors.
Domestic automation: washing machines, microwaves
Automatic navigation: aircraft, ships, cars (GSM satellite navigation)
Industrial robots: used to work on manufacturing lines. Can work non-stop, 24 hours a day, 365 days a year. Can work in hazardous areas
Expert Systems And Artificial Intelligence
Artificial Intelligence (AI) is the attempt to simulate the human brain, and its thought processes, using computer hardware and software. Expert systems use AI techniques to replace a human expert. All of the human's knowledge on a subject is entered into the computer as a series of rules.
Medical diagnosis: data is fed into the system, and questions are answered. The expert system rules then come up with the best diagnosis (usually with a % confidence level)
Speech recognition: checks voice patterns to determine what was spoken
Other areas
Computer-aided learning (CAL): CD-ROMs, etc. where you can learn at your own pace
Computer animation: for special effects in films and TV
The Social & Economic Implications Of The Use Of Computers
Social And Economic Effects
Effects on people, organisations and on society in general.
Redundancies: jobs lost when staff replaced by computer-based systems
De-skilling: replacement of skilled staff by computers. Staff are then left to do less skilled jobs
Electronic 'scabbing': if staff are on strike, work can easily switched to non-striking staff via a network, even in a different country
Tactical striking: unions maximise impact of strikes by selecting computing staff first. Whole company is then affected
'New tech,' agreements: benefits to workers (cleaner, safer workplace) and management (more cost-effective) of using computer- based systems
Economic Reasons For The Use Of Computers
There are many financial reasons for using computers, and computer controlled systems, even though they are expensive to set-up initially.
More efficient: tasks completed quicker, and with lest wastage
Work longer than people: automated systems need no rest, can work for 24 hours a day
Save on wages: computers can often do the work of several people, so people are made redundant
Changes To Existing Methods, Products And Services
Businesses change the way they work, and provide different, and better services to clients.
On-line banking: more convenient for customer, cheaper for banks, less real staff required to deal with cash
E-commerce: selling goods online means less overheads, so better prices for customers, and more profit for company
EPOS: (Electronic Point of Sale) tills in shops where the good purchased are automatically taken from the database of stock. Can automatically generate orders for new stock
EFT: (Electronic Funds Transfer) allows people to pay for goods using a card which is 'swiped' in the store, authorising the transfer of money from the customer's bank account
Development Of New Products And Services
Computers have lead to the development of new markets and businesses.
Internet service providers
Web-design services
Internet cafes
Changes In The Working Environment
Using computers within businesses has altered the environment that we work in
Cleaner and safer: dangerous / messy jobs done by computer systems
Work injuries can go up: due to prolonged computer use – RSI, back ache, etc.
Changes In Employment
The use of computers in the workplace has an impact on the way people work
Retraining of staff software packages upgraded, staff need to be trained. This is often a regular thing. However...
Individual training training can be personalised to staff's needs through the use of CAL systems, CD-ROMs, etc.
Privacy And Integrity Of Data
So much personal data is stored within computer systems that companies and governments have to have guidelines and laws to protect the privacy of people and their information.
Data Protection Legislation
The Data Protection Act gives the following requirements to anyone who stores data about someone else:
Person must give permission for data to be stored
Data must not be used for purposes other than those it was given for
Must not store more data than is necessary for the purpose
Data must be kept up-to-date
Data should not be kept for longer than is necessary
Data must be protected against unlawful access, or accidental loss
Data must not be transferred outside of EU unless the country also has data laws
Security And Reliability
Data must be protected. This involves a number of procedures.
Back-ups of critical data: should be performed on a regular basis. A full copy of all files is taken (can use CD-R, magnetic tape, etc.). Usual technique is to keep 3 generations of back-ups (today's, yesterday's and the day before's). This is the grandfather, father, son system.
Batch-Processing: Backup of both transaction files and master files required. If today's master file is lost, we can re-build it from yesterday's backed-up master file and transaction file.
Archiving of old data: to reduce the amount of system resources required (disk space, etc.) and keep the system running smoothly, old data that is no longer used (but may be required for future reference) is moved into an archive file.
Consequences Of System Failure
The requirements for security and reliability vary considerably depending on the nature of the application. For example, a failure during a batch update of a sequential master file is irritating and will cause delay, whereas a failure in an air traffic control system could well have catastrophic results.
Safety-critical systems (such as air-traffic control, or medical systems) have much more emphasis (and money) placed on reliability.
Hacking And Other Computer Crime
Computer crime includes activities such as the cracking of ineffective security systems to gain unauthorised access to commercially sensitive or confidential personal files, and fraud through the improper transfer of funds from one account to another. Computer criminals may work within the organisation or may be outsiders. Precautions can be taken.
Physical security: only allow authorised users near the computers
Complex security codes: use of good passwords (not just 'Fred' or 'Password')
Firewall soft/hardware: prevents access from outside the network
Encryption of data: can only be read by someone with the password
Monitoring of all access: trace users who are accessing and misusing system
Computer viruses
Sensible precautions should be taken
Up-to-date virus protection
Limited use of disks, etc from outside your network
Firewall software / hardware – prevents viruses using your Internet connection