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ICT
Unit 1
DataRaw facts and figures – on their own they have no meaninge.g. readings from sensors, survey facts
InformationData which has been processed by the computer. It has a context which makes it meaningful
KnowledgeIs derived from information by applying rules to it.Using information to make decisions
Data: 1,12, 1.4,2, 12, 1.2, 3,16, 1.1
Information: Swim times for 100m
Swimmer No Age group Times (mins)
1 12 1.4
2 12 1.2
3 16 1.1
Knowledge: Swimmer No 2 is the fastest in the age group.
Data processed into = Information when rules are applied you produce = Knowledge
Finding informationText Books/
magazines
Books may not be available at home / on loan
Internet/search engines
•Key word searches
•Interactive resources
•Editable information
•Copy and paste pictures / diagrams into reports
Email •Experts / teacher•Email could give faster response
Bulletin boards Post questions on them and reach wider audience
CD based software •Key word searches
•Lighter to carry home
•Copy and paste pictures / diagrams into reports
Chat •Ask questions to other students /tutors •Realtime -Ask further questions if not sure
Data typesData types
• Boolean– Can hold one of two values – true/false, YES/NO 1/0 e.g. are you disabled?
• Integer– Holds whole numbers only e.g. school years 7 8 9 10
• Real– Holds decimal numbers e.g. for storing currency
• Text/String– Holds any alphanumeric character, can include
numbers and symbols e.g. name , address, postcode, Tel no.
Coded DataCoded DataAdvantages• Save memory• Faster to type in• Less likely to have transcription errors• Greater consistency of dataDisadvantages• Value judgments fitting into a certain category or
group • Coarsen data by fitting it into groupsHow clever am I ?
•Thick•Average•Very•Genius
Cost of information3 categories
•Money•Time•Human resources
Data entry
Time
Collecting the data
Data collected directlyThe organisation or company has to produce a way of collecting information e.g. creating forms, questionnaires, sampling etc. In the case of forms and questionnaires, these will have to be printed, sent out and collected. Not all people respond to forms or questionnaires so many more will have to be sent out in order to get a fair sample back. Often, an incentive is given to encourage people to respond e.g. your name being entered into a free prize draw if the form is completed and returned. Data collected indirectlyThe organisation may have to buy the information or pay a third party to gain access to data.
Human Resource Keying inData keying takes time and staff will have to be paid to do it.Direct inputThere are automated methods of data entry - optical mark readers (OMR), optical character recognition (OCR), bar code readers, etc. Specialised hardware/software needs to be purchased and staff trained to use them.
MoneyData processing
Once the data has been inputted it needs to be processed into information. This requires hardware and software resources. The software may be ‘off the shelf’ or it may have been developed specifically for the organisation or company. Either way it will cost money.
Data maintenance
There are costs involved in making sure that data remains accurate and up-to-date. For example, an organisation maintains a database of its customers. The database will only remain accurate and up-to-date if changes to customers’ details are reported and then updated. This involves communication with customers and checking that their details are correct.
Learn examples
Good quality information is up-to-date, accurate, and complete, relevant and correctly targeted
Good quality information is up-to-date, accurate, and complete, relevant and correctly targeted
•Add value by aiding decision making Decision-making is based on information that is available at the time and if this is either out-of-date or incomplete then this can have a bad effect on the organisation or company.
•Monitor progress. Information obtained by market research (e.g. people in the street stopping certain passers-by, questionnaires sent to a sample of homes) and sales figures can help to achieve this.
•Can target reasoning and strategy making e.g. buy more of a certain commodity because sales are good. Advertising and marketing a product should be aimed at people likely to buy it otherwise it is a waste of time and money.
•Gain advantage over competitors. Information can tell an organisation how well it is doing compared to its competitors. For example information can identify gaps in a particular market which can then, on the basis of sound information be filled.
What if information was not kept up to date? Problem 1 Not updating shared files with amended data
It is essential to make sure that all copies of the data are updated so that everyone uses the same, amended data. If a customers orders extras on a new car but is either written down incorrectly or he changes his mind later then if order not amended the factory could make a car with all the extras and extra cost which the customer could refuse to pay for.
Problem 2 Out of date dataIt is no good having a mailing list when the addresses are no longer correct. When people move house, mail continues to be sent to the old address until the relevant mailing list is updated.Companies who sell their products through direct mail (junk-mail is the more commonly used name!) need up-to-date lists of names and addresses of people who are likely to be interested in their product. An out-of-date list is of no value whatsoever. Remember people move house, grow old, die, and change their interests or buying habits.Problem 3 Inaccurate dataAn automatic system using sensors to collect data might have faulty sensors and could inaccurate data could lead to a catastrophe e.g. chemical processes going wrong/ blowing up.
The task of keeping data up-to-date is expensive.
Methods used include:
• frequent updating (typing in the changes)
• frequent collecting of data through questionnaires, letters or checksheets
• interactive systems where a person can update his/her own detail
• deleting out-of-date data or data which is no longer needed
• making sure that all copies of the data are updated so that everyone uses the same, amended data.
Accurate data
What would happen if data was not accurate?
Example
A transposition error could occur typing
47465 instead of 44765
If a credit card number is typed in wrongly you may not be able to use it to buy goods
Errors on data entryVerification is the process of checking that data has been correctly copied from one media to another.
Visual checking for errors./ read it Double entry keying
Types of errors that can be found;•Transcription /typing errors Typing in the wrong character by accident egg 2 instead of a 7 •Transposition Errors i.e. keying in, in wrong order e.g. 56789 instead of 57689ExamplesDouble entry keying type password in twice when creating new accountVisual check/read it; In an online form read details of the form you have filled in before pressing Ok to confirm
ValidationValidation is checking that data issensible, fair and reasonable or is within stated ranges• Format checks• e.g. date is 2002/ 09.11 instead of 11/09/02
• Input masks e.g. entering data in a controlled way – Postcode if LLNN NLL– Input mask on a Text >L????????
Validation type Explanation Example in a school
Range checks Data is between statedranges
Admission No must be between 1 and 9999999999
Format checks Dates 12/04/03
Presence checks There must be a character present in a particular place e.g. the first 2 letters must be YR to represent yearMust be M or F
48123454 ( must start with 48 the branch code)
YR7
Bank Account no
Check digits Number added to a code Bar codes on library tickets
Date of birth Format checks 12/09/95
Range check between 1/9/86 – 31/8/94
Input masks 99/99/9999
Admission no Presence check e.g.
YGA 123454 ( must start with YGA)
Library code Check digit
Gender M or F
Field examples
Accurate Vs Valid
Data might pass all validation tests but might not be accurate!
e.g
You might type in your date of birth as
10/12/84 and this would pass the format check 99/99/99
But your date of birth might in fact be
12/10/84
Capabilities and limitations of ICT
Advantages over manual systems• Speed of processing including faster searches,
sorts etc.• Repetitive processing done to consistent
standard• Savings on storage space• Ease of updating data.• Accuracy and speed of data communications• Production of different output formats.
Factors affecting the efficiency of data processing
• Suitability of software for the task
• Ease of use of software and HCI
• Compatibility with other hardware and software systems
What could cause problems?• Changes in requirements during implementation• Insufficient testing. System may crash when unexpected input is
received e.g. an empty file.
• Initial poor communication with the user so the design does not match the requirements. System may fail to take into account data or processes required.
• Ability of the user to operate the new system. System could be technically good but beyond the skills of the users to operate.
• Cost of hardware and support (may need extra technical support/ new printers) Costs exceed possible benefits.
• Poor maintenance procedures (keeping files/ software/virus programs up to date). (See next slide)
• Poor post implementation procedures. ( See later slide)
Maintenance procedures
1. Perfective maintenance• Documentation kept up to date • Continual improvement of the system2. Adaptive maintenance• It may need to expand in some areas contract in
others or add new developments eg if the government introduces a new tax.
3. Corrective maintenance• Errors corrected eg wrong headings etc. which
might crop up.
How to avoid post implementation costs
• Make sure your initial systems analysis was thorough and you identified all the data flows and stores and fully understood what the user required.
• A detailed design is needed before implementation which should be agreed by the user.
• Consult with unions to avoid strikes and delays.• Make sure the system can cope with future
expansion
COMMUNICATIONS
Reasons for growth of networks• Falling cost of hardware and software so became more
widespread. • Growth of the paperless office managers used
wordprocessors , filing systems etc on their desk• Managers needed more rapid access to accurate and up
to date information.• Development of good and reliable telephone and satellite
communications• It is becoming more and more important to use new
methods of exchanging information rapidly and reliably
Definitions
What is a Network?• A computer network is a collection of computers
linked by network cabling. together so that they can communicate with each other sometimes a mainframe and sometimes a powerful microcomputer. Each workstation has a network decoder card into which the cabling is connected to the computer. The card is operated by a card driver software.
• A computer that is not connected to a network is called a stand-alone computer
The Bits That Make up a Network
Networking is not simply connecting up a few computers with cables. Here are some parts that can be found in a typical network.
SoftwareNetwork software may be part of the operating system (e.g. Windows98, Windows XP) or it can be special software for managing a network.
CablesConnecting cables are usually used to connect devices on a network, although some networks make us of radio or microwaves to provide the link.
ConnectorsConnectors are used to connect network cables to terminals or other devices..
Network Interface Cards (NICs)To use a PC as a terminal on a network it is necessary to include a device called a Network Interface Card inside the computer. A NIC looks like a small circuit board and slots into one of the connectors on the main circuit board (called the Mother Board) inside the computer. NICs have connectors on them for network cables.
Data Transmission
Communication Links
•For computers to communicate there needs to be a communication link.
•These links are not necessarily cables so you can not always see or touch them.
•Links can involve radio waves, microwaves or infra-red.
Metal cable
Metal cable consists of metal wires (usually copper) down which data is transmitted in the form of a varying current.
Fibre Optic cable
Fibre optic cable works by transmitting data as a series of pulses of light along a thin glass fibre. One bundle of fibres is used to send messages and a second bundle carries messages in the opposite direction.
Fibre optics are very good for transferring data because they are fast and do not suffer from interference like metal cables.
Cable Media
Wireless Media
Radiowaves
Here the data is transmitted as a series of radio waves.
Microwaves
Mobile phones use microwaves. Ideal for linking computers in two separate buildings fairly near to each other.
Satellite systems also make use of microwaves.
Infra-red
This works a bit like your television remote control. Infra-red signals can only travel short distances and this limits their use.
Often used to provide a link from a laptop computer to a printer so that data can be sent between the two without the need for a cable.
Computer NetworksThere are two different sorts of computer network:
•‘Local Area Network’ or ‘LAN’ - the computers are all in the same building or in different buildings on one site permanently connected to each other with special cables.
Server
Server
Server
Server
Server
•‘Wide Area Network’ or ‘WAN’ - the computers are spread over a large geographical area not permanently connected to each other communicate using telephone lines, radio transmitters or satellite links.
Advantages and Disadvantages of networksAdvantages
• Printers can be shared.
• Programs can be shared.
• Data can be shared.
• Users can communicate with each other.
• Users can email
• You don’t have to use the same computer.
Disadvantages
• Networks are expensive to purchase and maintain.
• If a network breaks down everybody is affected.
• Special security measures are needed to stop users from using programs and data that they shouldn’t have access to.
•Do not tell anyone your password
•Change password regularly
•Virus scan all discs
•Do not misuse the Internet e.g email, chat rooms
•No hacking
•Do not steal hardware / software
Network Topology
Network topology refers to the layout used to connect the computers together. There are three common topologies:
• Bus
• Ring
• Star
Any of these topologies can be used regardless of whether a network is local or wide area, server based or peer-to-peer.
BUS
LAN
RING
LAN
STAR
All communication takes place via a central computer.
WAN
LAN and WANsThese could form part of one wider network
e.gSupermarkets• LAN might control the POS terminal dealing with
proce look up prices, printing bills, recording sales
• WAN when stock is needed a message is sent to HQ who will deal with the reordering and dispatch from the warehouse
LANs and WANs
Advantages of using LANs To the customer
• * faster and more efficient checkout services. • * itemised till receipts. • * products more tailored to their needs. • * fresher goods due to low stock levels held by supermarkets. • * special offers. • * benefits to the supermarket passed on in the way of lower prices • * various methods of payment. • *Loyalty card/ pointsTo the supermarket and its management • * efficient stock control, less chance of goods being out of stock. • * more efficient checkouts, less chance of errors by staff. • * ability to use sales forecasts and 'profiles', leading to more efficient use of shelf space. • * little warehouse space required in each supermarket due to distribution system. • * ability to monitor the performance of checkout staff. • * shelf pricing more cost effective than labels on products. • * ability to use electronic funds transfer improves cash flow. • * effective management of chilled and frozen goods.
Disadvantages of LAN
But it's not all good. The organisation has to pay technical staff to maintain the network. User accounts need to be added and deleted as people join and leave an organisation. Because users' data is stored on the hard drives in the servers these need to be backed up regularly or there would be a public outcry if it were lost. Networks fail occasionally and then no one in the organisation can use the computers. As more users log onto the network, the servers have to share their time among them and the system may slow down. Users forget their passwords and can't log on, which causes additional work for the Network Manager. Or, because each user is allocated a specific amount of space on the hard drive, they exceed it and moan for more. And, users tend to get up to all kinds of naughty tricks like hacking into other users' areas, downloading or installing software that they shouldn't, stealing peripherals, clogging the system up with silly emails, forgetting to log off and so on. Security can become a major headache.
Advantages and Disadvantages of networksAdvantages
• Printers can be shared.
• Programs can be shared.
• Data can be shared.
• Users can communicate with each other.
• Users can email
• You don’t have to use the same computer.
Disadvantages
• Networks are expensive to purchase and maintain.
• If a network breaks down everybody is affected.
• Special security measures are needed to stop users from using programs and data that they shouldn’t have access to.
Network Security
There are three types of network security – PHYSICAL security, ACCESS security and DATA security.
Physical Security protects the Hardware. Some examples are:
• Serial numbers – Keep a record of all serial numbers.
• Alarms – Protect computer room with burglar alarms.
• Doors & windows – Locked when room not in use.
• Fire Protection – Use fire doors and smoke alarms
Access Security limits a persons use of the network
• All authorised users should be given user names and passwords. This will limit unauthorised access to the network.
• Passwords should be un-guessable and should never be told to anyone or written down.
• Users should change their passwords frequently.
• Unauthorised access can be reduced by assigning different users different access rights. For example, network managers can be given complete access to the network whilst other users may be limited to certain types of applications software such as word processors.
Data Security prevents accidental loss of DATA
• Regular back-ups should be made of the data on the system using suitable backup storage. The main method used to back-up network data is the Grandfather-Father-Son method.
• Back-up files should be kept secure – ideally in locked, fireproof rooms or safes in a different location to the network.
• Archiving means copying or moving files somewhere for long-term storage.
• Some software and files can be password protected.
• Restrict files to ‘read only’
Data Security prevents deliberate destruction of DATA
• Prevent access to data- Hierarchy of passwords:- ID / Authentification / Authorisation
Encryption: • Prevent access to rooms
Smart cards Retina scansThumbprint scans
• Prevent destruction by viruses Virus detection and eradication programs
Firewalls
The Internet
Connecting to the Internet•A computer with a modem and access to a telephone line is needed.
•Faster connection is possible with a special type of digital telephone line called an ISDN line which doesn’t need a modem.
•A separate Internet line can be leased.
•A leased line is a private telephone line which is permanently open 24 hours a day.
•Broadband; very high speed digital lines are available but these are expensive
•A router is a special piece of hardware which co-ordinates the switching of messages between the computers and the rest of the Internet.
•Wireless access
•Find an Internet Service Provider (ISP)
The World Wide Web (WWW)•World Wide Web is largest part of the Internet
•Pages of information begin at ‘home page’
•Pages are linked together using hypertext
•Hypertext generated using Hypertext Mark-up language or HTML
Browsers•To browse or ‘surf’ the Internet a browser program is required
•Microsoft Internet Explorer and Netscape Navigator use search engines to search for information by entering keywords
URLs•Uniform Resource Locator
•These give the location of individual sites on the World Wide Web
•Most start with http//:www.
•They often reveal the country of origin such as .uk for the United Kingdom. They also indicate whether the site is commercial with either .co or .com, a government organisation with .gov, or an academic organisation with .ac
http:// www. demon. Com /index
uses hypertext world wide web domain name top level specific pagemark up language (owner or type of domain site) org or country
Email Sending messages from one computer to another across a network
Videoconferencing Communicate visually with other Internet users.
E-commerce Buy goods online
Tele-banking Manage banking transactions, pay bills, transfer money between accounts etc
Web publishing Create and administer your own websites for specialist interests, etc...
Chat lines Send messages ‘Talk’ on-line
Broadcasting Music (MP3) and video
Downloading Software, drivers and other files
Services available on the Internet:
Online shopping•Allow Internet users to buy goods or services online any time day or night without needing to travel anywhere or get pushed around in crowded shops
•Some companies do all of their business over the Internet and reach a world wide market.
Advantages of online
shopping For the Company•Money doesn’t have to be spent on normal business overheads like renting shops and paying employees.
•Customers can be offered a much wider choice of goods because they can be ordered from suppliers as required rather than having to be kept available on the shelves all the time.
•Money is not tied up in unsold stock or wasted on products that aren’t popular.
•Data about customers and their buying habits can be collected directly and used to offer a much more personalised service tailored to suit the needs of an individual customer.
For the customer
• Shop 24 /7 365 days a year
• Saving on travel time and cost
• Disabled people able to shop
• Have wider variety of shops and goods to choose from
Disadvantages of online shopping
•Online transactions require users to enter a debit or credit card number before a purchase can be completed. There is a danger of these numbers being intercepted by hackers during transmission and used to make unauthorised purchases. The use of agreed words, secure payment sites, encryption and smart cards can help to protect against this.
•Criminals can set up fake web sites offering goods or services often using the name of a genuine company. This can lead to people spending money on goods and services that they will never receive as well as damaging the reputation of a genuine business.
•It is much easier for a business to gather information about its rivals by simply accessing their web sites — this can make it much harder to remain competitive.
•Hidden delivery charges
Online booking systems•Allow Internet users to check the availability of and book things like:
•Theatre, cinema and concert tickets
•Seats on coaches, trains and aeroplanes
•Hotel rooms
•An online booking system is essentially a web site that can be used to access a remote database
Advantages
•Overbooking should not occur
•Alternatives can be offered if 1st choice not available
•Access to wider database of information
Internet, Intranet and ExtranetThe Internet is a Wide Area Network - actually it is a huge collection of
networks connected together by what are called gateways - these make the system act as if it was one huge network.
• Many networks in industry, business, higher education and government institutions are all connected to the Internet although anybody can now get connected to the system with the appropriate hardware and software and access to an ISP (Internet Service Provider )...eg Freeserve, AOL, Demon and hundreds of others.
• A user can get information on just about everything. There are search tools which allow you to search the World Wide Web for any topic, and each page has links to another and so on....
• - it is also possible to download software and files (eg NASA graphics)• - bulletin boards (forums) or newsgroups are also set up where you can
leave messages, or communicate directly with other users.• Businesses set up websites on the Internet because...• ..they can advertise. It enables people to find out what they do and what
they sell. • ..people can email them with enquiries; orders; requests; • ..they can reach an international audience.
Intranets• An intranet is set up entirely within a LAN. Web pages can
be stored and accessed from anywhere on the network and email can be sent internally within the LAN.
• A company can set up an intranet and allow its workers to send messages to each other and use a browser to access company information saved as web pages. It can also be used for staff training.
Extranets• If a company allows some access from outside to its
intranet, then it becomes an extranet. Access would normally be through a firewall (software which only allows permitted users to access the data).
Advantages of the Internet•Easy communication with other people
•Valuable learning resource because Internet skills will be needed for jobs in the future
•Enables more people to work from home using computer networks (teleworking)
•A vast amount of information can be accessed
•Up-to-date information can be accessed on-line without the need to await publication
•Publishing documents on the Internet saves paper
•A valuable resource for companies to advertise and conduct business
What could happen• Hacking e.g. hacking into customer
accounts to misuse funds
• Spreading a virus e,g, to try to destroy confidential data or to crash servers
• Hack into private data and send abusive or blackmailing emails if customers in debt.
Dangers of the Internet
Dangers of the Internet •Hackers
•Firewall software
•Hierarchy of passwords
•Viruses
•Often spread via e-mail
•Virus detection and eradication programs
•Undesirable material and paedophiles in chat rooms
•Software to block sites
•Adult supervision
•Filtered service from ISP
Disadvantages of the Internet•Much of the information isn’t checked and may be incorrect or irrelevant
•A large amount of undesirable material, such as pornography, is readily available
•Messages sent across the Internet can be easily intercepted and are open to abuse by others
•Large telephone bills can easily be run up
•Too much time spent on the Internet could result in a lack of face-to-face interaction with others and a loss of social skills
•Going on-line runs the risk of hackers or viruses being able to damage your computer
The Computer Misuse Act 1990
•Hacking
•Blackmail using •computer
•Spreading a virus
•Illegal copying : -software piracy •Purchasing one legal copy and loading it into several computers memory•Downloading software over the Internet creating a copy.
The CopyrightAct
Illegal to copy software
People were worried that;
Data was wrong
Hacking into personal data
Being asked for data which was irrelevant to the purpose e.g. What is your religion ?
Length of time data was held on computer about them
Data given for on purpose e.g. medical data was being sold on to companies who produce mailing lists for junk mail.
The Data Protection Act
Demand to see data and have it correctedMust have good security passwords etc.
Justify and register why they need that data
Get rid of any unused data when finished with
Not allowed to sell data on.
1. Personal data shall be kept up to date and accurate .
2. Personal data obtained lawfully only for one purposes must not used for another
3. The data must be relevant to the purpose for which it is given
4. Personal data shall not be kept for longer than is necessary
5. It should be kept secure against unauthorised access and loss
6. Personal data shall not be transferred to a country outside the EEC
Exemptions on data1. Personal data required by the Inland revenue
2. Personal data used by national security or a solicitor in a legal case
3. Personal data kept by the user on himself or family e.g. files on birthdays, addresses etc.
ICT
Unit 1
Software and
Applications
Wordprocessing / DTPWordprocessing / DTP
EditingAlter text and graphics and save FormattingText styles, paragraph styles, bullets etcTemplatesMaster documents which are stored havepredefined layout e.g. letter headed notepaperStyle sheetsHave predefined indents, tab settings and
subheading styles
Mailmerging
• Automated document
• Data from an external database is imported / merged into a document
• In pre-defined places in the document
Graphs• It is a pictorial representation of data• Easy to read data in graph form than in lists or tables. Instant transfer
understanding• e.g. Graph of patient blood pressure readings
Templates• A permanent document which has predefined format and layout• Saves redoing layout for a firm spreadsheets each time.• Standardises image.• e.g. Prescription templates
Statistics • Library of equations and calculations • saves time• Use of commonly used standard functions such as SUM AVERAGE MIX
MIN etc • e.g. Average weight, Maximum blood pressure
SpreadsheetsSpreadsheets
Presentation Software
•TemplatesBackground styles and themes with each slide being the same as the master slide. Has same logo colour scheme layout etc•Animated transitions Movement and direction of text and picture. Graphical display when moving from one slide to another•Formatting Use of font styles and sizes bullet point scheme for headings and subheadings
Web AuthoringWeb Authoring
• Frames to work in and control layout• Hyperlinks to other web pages• Hotspots are hyperlinks on graphics/
pictures to other web pages or other parts of the web page
• Bookmarks are hyperlinks internally to other parts of the web page
• HTML language code for creating web pages
Database Software• IMPORT EXPORTTransferring of data between software packagesExample Mailmerge where data is exported from a database and imported into a document to send details of special offers
• QuerySearch for data with specific criteria.
Example looking for customers who all live in a certain postcode to arrange delivery of goods.
• ReportOutputting information in a printed format.
Example Printing customer bills with data from the customer accounts.
Flatfiles vs relational databases Database
–A large collection of related files of data items and links between them, structured in a way that allows it to be accessed by a number of different applications programs.
File –a collection of related records
Records–The basic unit of data stored in a data file.–It is a collection of items which may be different data types, all relating to the
individual or object the record describes.–It is treated as a unit for processing.
Fields–Is part of a record designed to hold a single data item of a specified type.–Holds data items of the same data type
Primary Key–It is a unique value which is used to identify a record.
Members Bookings Staff Flatfile
Members
Staff
BookingsMembers
StaffRelational database
Advantages Disadvantages
Minimise s data duplication More expensive to create
Ensures data consistency DBMS needs full time maintenance
Ensure data integrity
Controls data redundancy
HCI’sHCI’s
• GUI’s Windows Icons Menus pointer, online tutorials – good for inexperienced user .-children.
• Dos text based has short cut keys- expert user such as computer programmers
• Menu driven when want to limit choices• Voice –disabled people / dyslexic• Braille keyboard, concept keyboards,
touch sensitive devices Special needs
Features of a GUI
• WIMP (windows, Icons, menus, pointer)
• Online tutorials
• Help / office assistants
• Customised environments e.g. font sizes/ backgrounds favourite
• Intuitive - easy to learn
Computer Assisted Learning (CAL)
Tutorials
Special needs pupils;
Spelling programs which have an interactive component testing student with games, quizzes and tests. A scoring system allows students to assess their progress. Often after 3 tries the answer or clues will be given to them.
Picture and sound are used to enhance the experience.
GCSE revision programs
ICT in Education
Computer based training
DISTANCE LEARNING Students not always be in the same place as the teacher.Distance learning course where the tutor is in North Wales. Students are provide with course booklets and practical work and videoconferencing is used to discuss problems that ariseAssignments are marked electronically.
Online courses e.g Open UniversityThese can be intranet based in universities or Internet based.Some university modules are completely computer based with knowledge sections and task sections. The software records how much of the course you have covered and if you do not complete the full module you will fail the module.
E – learning sites are now available. Subscribers can even do A levels online approved by exam board such as OCR. Schools in England are given E-learning credits which they can use to purchase online courses.
Chat rooms to discuss courses and problems with tutors.
DISTANCE LEARNINGStudents not always be in the same place as the teacher.
Distance learning course where the tutor is in North Wales. Students are provide with course booklets and practical work and videoconferencing is used to discuss problems that ariseAssignments are marked electronically.Online courses e.g Open UniversityThese can be intranet based in universities or Internet based.Some university modules are completely computer based with knowledge sections and task sections. The software records how much of the course you have covered and if you do not complete the full module you will fail the module.. E – learning sites are now available. Subscribers can even do A levels online approved by exam board such as OCR. Schools in England are given E-learning credits which they can use to purchase online courses. Chat rooms to discuss courses and problems with tutors.
School registration systems
1. OMR sheets Optical mark sensing.
Teachers are given an OMR form with class lists each week and they put a
black mark whether present or absent. The form is read by computer and an
absent list produced. The teacher marks the reason for the absence in the
correct space on the OMR form.
2. Radio signals
In some school the teachers have a computer with a wireless link to the
admin server. Teachers fill in an attendance form at the beginning of every
lesson and this is wirelessed up to
the office
3. Smart cards
Each pupil has their own smart/swipe card which they swipe through a
computer at the beginning of registration and every lesson. This data is sent
to the office either by wireless or by file transfer.
Advantages• Know which pupils are in and are late• Know where pupils are all times if year tutor wants to see
them• Printout report summary to check pupils % attendance.
Disadvantages• Wireless coverage for all rooms may not be available. • Initial cost of purchasing electronic equipment• Cost of maintenance and repair – need technical support• Pupils might swipe their friends cards into a lesson.- teacher has not
checked relied upon the machine to do it.
Advantages of using ICT FOR TEACHING AND LEARNING
• Greater interactivity holds a pupils attention.• Quicker feedback in online tests• Offers a variety of different ways to learn and a variety of information sources.• Allows user to learn at own pace and can learn at times suitable for themselves.• Allows user to ‘go over’ earlier work again in case they did not understand i.e repeat sections they
found difficult earlier.• Computer based training significantly reduces costs for the employers and can be safer if it is a
danger
Advantages of using ICT FOR ADMINISTRATION• Improved speed of access to data - faster searches/ e.g looking for all the pupils in a particular form
and faster sorts e.g. listing pupils by alphabetical order of Surname.• A variety of output formats available e.g. printed reports, mailmerged documents. Etc.
– Faster and simpler to transfer data e.g. exam entries• Saves time when reproducing standard letters e.g. lettes to parents informing them about parents
evenings, school sports day programs. Such documents will only have minor changes each year.
• Increased security• Saves on storage/office space
Problems with using ICT in Education
ICT is expensive and requires a great deal of capital investment which is constantly updated and has to be maintained. Maintenance contracts can run into thousands of pounds which takes money away from traditional teaching materials such as books.
Unfair distribution of ICT resources and hence learning opportunities.Richer schools will have greater resources.
Cuts down on social interaction skills Some educationalists argue that younger pupils do not have as great an opportunity for group learning. Text messaging has been blamed for a reduction in spelling skills because of the use of abbreviations.Lack of personal support.Distance learning does not provide the personal support needed by most students as and when they need it, particularly crucial when a student lacks confidence or cannot interpret the written instructOver reliance e.g. if there is a power cut you cannot use it.
C.A.M. Computer Aided Manufacturing
• Design with CAD
• Produce with CAM
CAD / CAM Computer Aided Design and Computer Aided manufacturing
Design in CAD software Make in CAM
e.g. design a model car and cut it out using computer controlled lathes and CAM
Feature of CAD Definition Advantage
Hatching or rendering Different finishes or materials can be displayed
Can do many ‘what if ‘ type investigations to explore the best finishes
Zoom Enhance parts of a drawing to make it bigger
To produce work of more detail or add detailed design
Rotate Rotate in 3D across X Y and Z axis See design from all angles on the outside
Walkthrough Visit rooms etc in 2D Allows spatial awareness of what the design looks like in relation to other features
Costings Produce estimate of cost of building materials
Automatic estimates are given and designer can investigate different options or work within a budget.
Stress and strain Working out the weights materials can take
Avoids disasters later on when building as the designer should build well within the safety requirements
Wire drawings See design without any finishes or solid form
Helps with perspective and working out stresses and strain areas
Disadvantages of CAD CAM
• Software very expensive
• Hardware / Memory / processor / screen requirements needed
Computer control in hospitals
Sensors
• Temperature
• Heart rate/pulse
• Blood pressure
• Breath gasses
• Brain wave patterns
• ECG
Advantages• 24 hour monitoring• Alarms or immediate response if problem arises• Trend analysis for research work
Disadvantages
• Over reliance
• Expensive to buy
• Specialist staff to maintain equipment.
Computer control in hospitals
Scanners
• MRI Magnetic resonance image
• Takes slices of images through the body
• CAT Computerised axial tomographyAdvantages
•Allow doctors to see inside the body weithout surgery
•Less chance of post operation infections
•More accurate diagnosis
Disadvantages
•Very expensive
•Over reliance may loose traditional diagnostic skills
Life supportLife support
Intensive care units need
• Power supply backup
• Computer backup
Expert Systems
• An expert system is a computer system which emulates the decision-making ability of a human expert.
• A knowledge-based system which attempts to replace a human 'expert' in a particular field.
• It diagnoses problems and gives advice on that the cause of those problems are. They can also give advice on solutions.
3 parts of an expert system
• Knowledge database
• If then Rules / inference engine
• HCI to ask the questions
Medical diagnosis The computer does not take the place of the doctor but can be used to help the doctor make decisions.An expert system would have information about diseases and their symptoms, the drugs used in treatments etc.
A patient is asked by a doctor about symptoms and the replies are input to the expert system. The computer searches its database, uses its rules and makes suggestions about the disease and its treatments. Sometimes probabilities are assigned to diagnoses.One of the most famous example is;
MYCIN, an Expert System for diagnosing and recommending treatment of bacterial infections of the blood
CaDet is a computer-based clinical decision
support system for Early Cancer Detection.
Cancer risk evaluation and early detection are subject to serious limitations mainly related to human factors and to characteristics of the data involved. To help overcome these problems, a computer-based system was designed to provide the physician with a clearer clinical picture and aid in directing patients to appropriate measures
Apache III (Acute Physiology and Chronic Health Evaluation)
• The APACHE III system was designed to predict an individual's risk of dying in the hospital.
It compares each individual's medical profile against nearly 18,000 cases in its memory before reaching a prognosis that is, on average, 95 percent accurate. A physician can give the computer system 27 easily obtained facts, and the program would predict that patient's risk of dying in the hospital. The system is also useful in answering the question: Is treatment making a difference? Studies have shown, that about half the deaths in American Intensive Care Units now occur after a deliberate decision has been made to stop "heroic" measures
ACORN (Admit to the Ccu OR Not)
ACORN is an expert system for advising on management of chest pain patients in the emergency room.
Medical audits determined that 38% of patients attending with acute heart disease were sent home in error and the Average time until admission for the remainder was 115 minutes. ACORN was built for use by doctors and senior nurses to assist in the management of these patients. The system was in routine use at Accident & Emergency Department Westminster Hospital, London
Advantages.• The computer can store far more information than a human. It can draw on a wide variety of sources such
as stored knowledge from books case studies to help in diagnosis and advice.• The computer does not 'forget' or make mistakes. • Data can be kept up-to-date. • The expert system is always available 24 hours a day and will never 'retire'. • The system can be used at a distance over a network. So rural areas or even poorer third world countries
have access to experts.• Provides accurate predictions with probabilities of all possible problems with more accurate advice.• Some people prefer the privacy of talking to a computer.
Limitations /Disadvantages of expert systems • Over reliance upon computers• Some ‘ experts’ could loose their jobs or not be given training if computers are available to do the job. • Lacks the 'human touch'! – lack of personal contact• Dependent upon the correct information being given. If data or rules wrong the wrong advice could be
given.• Expert systems have no "common sense". They have no understanding of what they are for, nor of what the
limits of their applicability are, nor of how their recommendations fit into a larger context. If MYCIN were told that a patient who has received a gunshot wound is bleeding to death, the program would attempt to diagnose a bacterial cause for the patient's symptoms.
• Expert systems can make absurd errors, such as prescribing an obviously incorrect dosage of a drug for a patient whose weight and age are accidentally swapped by the clerk.
ICT in Hospital Admin
Advantages
• Faster searches
• Reminder letters for appointments
• Keep files up to date
Database of patient records
New developments
• Bar coding of blood and tracking systems
• Barcodes on patient ID tags
• Electronic patient record keeping
• Distributed medical databases
• Use of internet, email and videoconferencing for medical diagnosis
• Online access to medical journals
Computers for home entertainment
• Interactive television
• Computer games
• Digital photography
• Music downloading and sound file creation
A gaming PC
Using a PC• You can buy a game on disc.• There are many gaming sites some of which some are free but
others you have to pay a subscription. • The speed of the processor is very important.Many PC users buy • Fast processors• graphics cards• sound cards and speakers• Joysticks gaming keypads steering wheels etc
Using Interactive digital TV• Sky has gaming channels
Problems
• Anti social behavior (not mixing with others).
• Lack of fitness through sitting down for long hours at a
• Cost Sky gaming cost 75p per minute of telephone charges.
Interactive TV
• Pay to view movies / sports channels
• Shopping
• Betting
• Dating
• Cinema and holiday booking
Online Booking SystemsBook cinema or theatre tickets, holidays etc.• Theatre and, concert tickets, holidays, flights etc, can be
booked using both interactive television and the Internet. The home user can now access remote online databases for their computer enquiry and booking system.
• People can search for holidays etc. to suit their requirements and make provisional or firm bookings
Advantages to the online booker• Services are available 24 hours a day• Bookings can be made at home• Alternatives can be proposed if first choice not available• Access to data on a wide range of holidays including
special offers.• Bookings are instantaneous so little possibility of
overbooking because once a seat or holiday is provisionally booked this will appear on the database
Tele-shopping / E-Commerce This means selling goods and services over the Internet or
through your interactive TV.On the Internet• Businesses set up websites on the Internet because...• ..they can advertise. It enables people to find out what
they do and what they sell. • ..people can email them with enquiries; orders; requests; • ..they can reach an international audience. Through the Interactive TV• There are special shopping channelsAdvantages • Can buy 24 hours a day, 365 days a year • No need to handle cash since all transactions are made
using cards • Less staff needed
Mobile phonesTo many people mobile phones are not only a form of communication but of entertainment•Advantages of mobile phone •Use anywhere there is a signal•Text messages•Voice mail•Alarm clock/time•Reminders/ to do list•Change ring tone•Record greeting message•Display photos/ pictures on screen•Radio
•Disadvantages of using mobile phones•No service•No battery/ run out of credits•Fined if used when driving•Run up large phone bills•Get mugged•• Some can receive the Internet
EFTPOS• Banks can move money between one bank
account and another electronically over computer networks. This is called Electronic Funds Transfer or EFT for short.
Online or Homebanking • Customers can access their bank account
details from home across the Internet
Online banking
Advantages of home online banking
• Can buy 24 hours a day, 365 days a year • Customers don’t have to leave home to pay bills
etc so savings on postal or travel costs• No need to handle cash since all transactions are
made using cards –less chance of getting mugged• the transactions are automatic, saving staff costs • the customer can print off an on screen receipt • the delivery process can often be tracked online • goods are often discounted because of lower retail
costs
Problems• Hacking of credit card / debit card details - people who
might misuse the data.• Have to pay telephone charges whilst online.
Security• Unauthorised access prevent by PASSWORDS or PIN
No• An authorisation and authorisation code are generated if
there is enough money in the shopper's account to pay for the goods. A record is created to settle up between the shopper and retailer's banks 2 or 3 days later. Alternatively, the authorisation may be rejected because of insufficient funds in the account leading to problems of not paying bills on time.
• Open to computer fraud e.g. ghost sites
Card crimes and prevention• Stealing cards at ATMs/ Stealing debit and credit cards• Do not write down PIN numbers• Do not let anyone see you typing in your Pin number • Photos on cards• Lower the amount that can be spent using cards before
seeking authorisation• Details of stolen cards put on POS terminals• Chip and PINCredit card fraud on the Internet and their misuse• Use agreed words on some sites• Use a secure service/ESCROWCard copying• Programmable smart cards to make data difficult to copy• Use of holograms to make cards difficult to copy.• Put extra 3 digit security code on back of cards
Digital photography
• Digital cameras• Flash memory• Dedicated photo printersAdvantages• Instant processing• Special effects• Print only what you want /electronic albumDisadvantages• Cost of photo paper and ink
Music and soundDownload music from the Internet. There are many sites where you
can listen to music both old and the latest releases as a try before you buy.
Problems• Copyright laws forbid the illegal copying of music including
downloading from illegal sites.Create own music using instruments such as electronic keyboards
with Midi interfaces• Digital sound technology allows you to create edit and hear your own
music. PC must be fitted with a quality sound card • Inputs can come from microphones, electronic keyboards, drums
etc. with midi interfaces
• MIDI (Musical Instrument Digital Interface) is an industry standard format applied to instruments. It is a very compact format e.g. 1 minute of midi synthesized music takes up 30kb of disk space. Compared with 600kb of low quality recorded sound.
Music Software.There are three types of music software
A sequencer This is a multi track recording studio builds up complex files by layering them with simpler ones. ‘Magix Music Maker’ has over a 1000 sample music files and sounds which can be used by the non musician.
NotatorsThis is music composition software.Musicians write music scores in the traditional way on the computer and the computer plays it. Again it can be edited, change the tempo add lyrics extract individual instrument parts etc.
Sound Wave EditorsA third type of software allows you to edit sound waves. I.e. it allows the digitized sound wave pattern to be edited. It is often used to strip away ‘noise’. But it can also be used to change the words people have recorded. Software such as this has led to recorder evidence being discredited in some law cases.
In a supermarketInput devices POS HAND HELDBar code scanners SEC shelf edge computersCard scanners, Scales KeyboardsOutput devicesPrinters LCDSpeakersStorage devicesBranch and HQ file stores
ICT and Shopping
Lans and Wans
• The supermarket uses several computers which are located in a room known as the system office and form the supermarkets own LAN (Local Area Network). These computers are used to control the stock and are connected to the checkouts. These are the 'branch computers'. The computers are multi-functional, and each can access the data, which gives the management a number of access points.
• These branch computers are linked to a WAN (Wide Area Network) when linked to the Headquarters main computer system which in turn is linked to the distribution centre computers
Input devices
SEC (Shelf Edge Computers). These are used for price changes, creating stock pictures (information on stock totals) and for forecasting deliveries.
Located at each checkout is an ELECTRONIC POINT OF SALE ( EPOS ) till. This EPOS till comprises a ,keyboard, barcode scannerset of scales, credit / debit card reader printer, digital display,
Barcodes
a) The first 2 digits represent the country from which the company producing the product comes. 50 - U.K. b) The next five digits represent the company which produced the product. 00208 - Lyons Tetley Ltd. c) The following five digits represent the product. 02100 - 80 Tea bags. d) The last number is a check digit. This is used to make sure the bar code has been read correctly. So 5000208021000 is the EAN for a box of 80 Tetley tea bags.
European Article Number or EAN. This is a thirteen digit number which can be used to uniquely identify a product. Each product to be sold must have an identifying code number which is different from that of every other product. Different sizes of the same product even need different code numbers.
Card readers
• Not every customer pays by cash or cheque though. Many now opt to pay by a debit card such as Switch or Delta. In these cases the customer’s card is swiped through the card reader which reads the information ( such as the account number and date of expiry ) held on the magnetic strip on the back of the card. The latest in store development has been the arrival of smart card readers at the EPOS. A debit card with a smart chip is placed in the reader and the customer then enters their PIN to authorise the money being taken out of their account. This is much more secure than signing a docket as it cannot be forged.
Finding the price
The branch computer then searches its stock file for the product matching the EAN number. When this record is located the price and description of the product is extracted and sent back to the EPOS till at the checkout which then shows this item and price on the digital display, prints them on a receipt and adds the price to the total. At the same time, the branch computer records that one of this item has been sold
The scales at the EPOS till are also linked up to the branch computer. As well as giving the description and price. The weight of the product is also deducted from the stock file.
Output devices
Printer• As well as printing an itemised receipt, the
printer attached to the EPOS till can also print the name of the supermarket, the date and the amount owing on cheques and debit / credit card vouchers. This lessens the chance of mistakes as well as minimising the amount of time a customer has to spend at the checkout
LCD Display• Customer can see prices and total amount
owed.
Special offers and loyalty cards
• Special offers such as Multibuy - "Buy two and get one free" or LinkSave - "Buy one product and save 50% on another" could not be offered before the introduction of Information Technology. As bar codes are scanned, the branch computer looks for items which are on special offer and discounts the prices where necessary.
Storage
• There are, in fact, six branch computers linked to the EPOS terminals at the checkouts. They all record information about items sold and provide backup for each other. If only one computer was used and it broke down, the supermarket could not function. These branch computers are linked via the satellite links to a large main computer housed at the supermarket's head office elsewhere in the country. All branches of this supermarket are also linked in this way to the main computer and this is an example o an extranet.
Stock Control
• The branch computer sends the details of every individual sale to the main computer at the H Q updates its record of the number in stock of every item in the store.
• SEC allows managers to get a real time stock picture and allows a manager to escalate stock deliveries from nothing to 72 hours to 48 hours
• Using a forecast of sales along with other factors ( such as the weather and the time of the year etc. ) the system automatically orders the correct amount of stock required by the store for the next available delivery 48 or 72 hours ahead.
• The main computer also transmits these orders to computers in the distribution centres across the satellite link.
• Distribution centres then deliver the required stock to the stores immediately.
• Price changes and prices of new products, special offers etc. are sent back to branch computer in the supermarket.
• New shelf labels are printed and the night staff of the supermarket place these on the shelves
Shopping patterns
• on the main computer at the Head Office to build up a 'profile' or description of the way in which its customers shop
• From this sort of information, the amount of shelf space to be given to a product can be calculated.
JUST IN TIME v STANDARD METHOD OF STOCK CONTROLThe ‘just-in-time’ system takes advantage of a stock information system. As products pass through the electronic points of sales (EPOS), the relevant data is sent to a database containing information about stock levels. When stock falls below a set level more is ordered. Thus only a bare minimum of necessary stock is ordered and there is no need to maintain a large, fully stocked warehouse. In some cases the system is fully automated, working out how what stock is needed and electronically processing and communicating the order.
Advantages• Money is saved because less warehouse space needs to be
purchased and maintained.• Economies can be made in regard to labour costs, i.e. fewer staff
are needed.• The business is more aware of and more responsive to changes in
supply and demand
Disadvantages
• If there is disruption to the transport system, shops and businesses will quickly run out of stock.
• Shops can still be caught out by sudden changes in buying patterns. In such cases they often find themselves without the stock the customers are asking for.
• An ICT system can be costly to set up and maintain, and expertise - which may also be costly – will be needed to run it.
E Commerce
• As a means of communicating information about the products and services they offer;
• As a ‘virtual shop’, allowing customers to purchase goods and services online;
• As a free service which makes money by advertisers to use the site;
• As a subscription service, e.g. allowing subscribers access to valuable information such as might be contained in research papers;
• As an interactive site that encourages customers to give them feedback on their products.
Steps in interactive shopping• The customer views the company’s products via a
website and selects the object(s) for purchase.• The customer enters his order, together with credit
card details, via an on-screen form.• An encryption system or secure link is used to protect
the transaction and to ensure credit card details are not accessible.
• The order is received and sent to a database.• The information in the database is communicated to a
distribution centre where orders are made up.• The order is delivered to the customer.
Advantages to the customer
• Customers do not have to travel long distances to the shops and struggle through crowds to make their purchases.
• It can be beneficial to those customers who are disabled or who, for some other reason find it difficult to travel to shops.
• New, smaller, more specialised businesses present themselves on the web, thus widening the range of goods and services available.
• Money doesn’t have to be spent on normal business overheads like renting shops and paying employees.
• Customers can be offered a much wider choice of goods because they can be ordered from suppliers as required rather than having to be kept available on the shelves all the time.
• Money is not tied up in unsold stock or wasted on products that aren’t popular.• Data about customers and their buying habits can be collected directly and used to
offer a much more personalised service tailored to suit the needs of an individual customer.
Advantages to the business
• Overheads can be cut. A web-based business does not necessarily need a high street shop and staff to run it. Small specialised concerns have therefore been able to establish themselves on the web with very little capital outlay.
• Many new businesses have been created via the Internet; some have been successful some not. The overall effect, however, has been to invigorate the business environment by introducing healthy competition.
Some difficulties
• Despite assurances by business that their sites are secure, many people are anxious about giving out their credit card details online. There have been sufficient examples of Internet-based credit cards fraud to justify this fear.
• Anybody can set up an online business and some websites are not run in an honest and reliable manner. Customers have ordered and paid for goods that hve never arrived.
• Shopping is not just a functional act. It is also a social activity. People go shopping to be with their friends and enjoy the atmosphere of towns and cities.
Control in a supermarket• Computers are also used to control the freezers and chillers
throughout the store.. • A temperature sensor in each freezer or chiller constantly
MONITORS the temperature, sending data back to this computer which sends signals back, when needed, switching the individual freezer / chiller motors on or off, thus maintaining the correct temperatures. A display on each freezer / chiller shows the temperature to customers.
• This is called a 'closed loop control system'. • As can be seen from the diagram, the freezer can be either on or off
( the PROCESS ) which leads to the freezer being a certain temperature ( the RESULT ). The temperature of the freezer is then either too high, too low or alright and this FEEDBACK is used to change the process if necessary (turns the freezer from off to on, or on to off.)
• Every three or four hours, each freezer • has to be defrosted and the computer • controls this process as well.
Summary of advantages To the customer • faster and more efficient checkout services. • itemised till receipts. • products more tailored to their needs. • fresher goods due to low stock levels held by
supermarkets. • special offers. • benefits to the supermarket passed on in the way of
lower prices or increased • customer services and loyalty cards• various methods of payment. • chilled or frozen food kept at the correct temperature.
To the supermarket and its management
• efficient stock control, less chance of goods being out of stock.
• more efficient checkouts, less chance of errors by staff. * ability to use sales forecasts and 'profiles', leading to more efficient use of shelf space.
• little warehouse space required in each supermarket due to distribution system.
• ability to monitor the performance of checkout staff. • shelf pricing more cost effective than labels on products. • ability to use electronic funds transfer improves cash
flow. • effective management of chilled and frozen goods.
Disadvantages of using computer based shopping systems.
Automatic stock control• If there is disruption to the transport system,
shops and businesses will quickly run out of stock.
• Shops can still be caught out by sudden changes in buying patterns. In such cases they often find themselves without the stock the customers are asking for.
• An ICT system can be costly to set up and maintain, and expertise - which may also be costly – will be needed to run it
Disadvantages of E commerce
• Anybody can set up an online business and some websites are not run in an honest and reliable manner. Customers have ordered and paid for goods that have never arrived.
• Shopping is not just a functional act. It is also a social activity. People go shopping to be with their friends and enjoy the atmosphere of towns and cities.
• Online transactions require users to enter a debit or credit card number before a purchase can be completed. There is a danger of these numbers being intercepted by hackers during transmission and used to make unauthorised purchases. The use of agreed words, secure payment sites, encryption and smart cards can help to protect against this.
• Criminals can set up fake web sites offering goods or services often using the name of a genuine company. This can lead to people spending money on goods and services that they will never receive as well as damaging the reputation of a genuine business.
• It is much easier for a business to gather information about its rivals by simply accessing their web sites — this can make it much harder to remain competitive.
General disadvantages
• Over reliance assuming temperature sensors are correctly calibrated.
• Embarrassment if POS won’t read card
• Power cuts means shops will have to close
Advantages of using ICT
• Speed of processing
• Accuracy of processing of repetitive tasks
• Fast transmission speeds
• Different output formats graphs reports etc
• Save and edit work in future
Factors affecting the efficiency of use of ICT
Factors affecting the efficiency of use of ICT
• GIGO• Suitability of hardware and software for
task• Level of user ability• Changes in circumstances of during
development of the computer system• Poor implementation and maintenance
procedures• Cost restrictions on solution
Hazard Prevention
RSI repetitive strain injury caused by prolonged working at computers or computer games
Ergonomic keyboards ; wrist and foot supports: correct chair positioning
Eye Strain and epileptic fits Non flickering screens; Screen filters t remove glare; correct lighting in the room
Back problems Adjustable chairs; foot supports:; tilting screens
Ozone irritation from laser printers Locate personal laser printer 1 metre away from user
Radiation affects embryos leading to miscarriages No real evidence for this