Ict theory

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Applied I CT theory


1. ICT Systems Input Devices: keyboard, mouse, touchpad, scanner, touch screen, graphics tablet, microphone, webcam, barcode reader, OMR, OCR, magnetic stripe reader, remote control. Know the range of input devices, suitable uses and advantages and disadvantages.

Worksheets on input devices

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Output Devices: crt monitors, tft monitors, laser printers, dot matrix, plotters, speakers. Know the range of output devices, suitable uses and advantages and disadvantages.

Output Device

Uses

CRT monitor

Applications where space is not a problem. Applications where more than one user may need to view screen simultaneously such as in design use, e.g. when several designers may need to offer suggestions on a prototype.

TFT monitor

Applications where space is limited such as small offices. Applications where only one person needs to view the screen such as individual workstations.

Laser printer

Applications which require low noise and low chemical emissions, e.g. most networked systems. Applications which require rapid, high quality and high volumes of output, e.g. most offices and schools.

Inkjet printer

Applications which require portability and low volume output where changing cartridges is not an issue e.g. small offices and stand alone systems. Applications which require very high quality output and where speed is not an issue, e.g. digital camera applications.

3D inkjet printer

CAD/CAM applications where 3D designs are actually made by layering of resin powder.

Dot matrix printer

Applications where noise is not an issue and copies have to made, e.g. industrial environments (multipart forms, continuous stationery, labels etc.), car sales and repair companies, manufacturing sites.

Graph plotter

CAD applications, particularly where large printouts are required such as A0.

Speakers

Any application which requires sound to be output such as multimedia presentations/web sites including encyclopaedias. Applications that require musical output such as playing of music CDs and DVD films.

worksheets on output devices 3


Control Output Devices: actuators, motors, buzzers, lights. Know the range of control output devices, suitable uses and advantages and disadvantages.

Control Devices in Control Applications Motors

Automatic washing machines, automatic cookers, central heating controllers, computer-controlled greenhouses, microwave ovens, robotics, production line control

Buzzers

Automatic cookers, microwave ovens

Heaters

Automatic washing machines, automatic cookers, central heating controllers, computer-controlled greenhouses

Lights/lamps

Computer-controlled greenhouses

Backing storage media and devices: magnetic tape, hard disks, portable hard disks, CD/DvD Roms, & RWs/RAMs, blu-ray disks, minidisks, memory sticks, flash memory. Know the range of backing storage devices, suitable uses and advantages and disadvantages.

Storage Device

Uses

Floppy discs

Any use where small files such as word processing, small spreadsheets and databases need to be moved from one computer to another. Useful to backup small data files. Many computers no longer come with these devices as they are fast becoming obsolete

Fixed hard discs

Used to store operating systems, software and working data. Any application which requires very fast access to data for both reading and writing to. Not for applications which need portability. Used for online and real time processes requiring direct access. Used in file servers for computer networks.

Portable hard discs

Used to store very large files which need transporting from one computer to another and price is not an issue. More expensive than other forms of removable media – these are sold under the name Passport and can hold 250 Gb + of data. As they work just like Fixed Hard Disc Drives, the link compares the prices of this new and upcoming device.

Magnetic tapes

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Any application which requires extremely large storage capacity and speed of access is not an issue.


They use serial access for reading and writing and can be u Used for backups of file servers for computer networks. They are also used in a variety of batch processing applications such as reading of bank cheques, payroll processing and general stock control. Optical backing storage media such as CDs and DVDs

CDs tend to be used for large files (but smaller than 1Gb) which are too big for a floppy disc to hold such as music and general animation. DVDs are used to hold very large files (several Gb) such as films. Both CDs and DVDs are portable i.e. they can be transported from one computer to another. Both can be used to store computer data.

CD ROM/DVD ROM

Applications which require the prevention of deletion of data, accidental or otherwise. CDs used by software companies for distributing software programs and data; by music companies for distributing music albums and by book publishers for distributing encyclopaedias, reference books etc. DVDs used by film distributors

CD R/DVD R

Applications which require a single ‘burning’ of data, e.g. CDs – recording of music downloads from the Internet, recording of music from MP3 format, recording of data for archiving or backup purposes. DVDs – recording of films and television programs.

CD RW

Applications which require the updating of information and ability to record over old data. Not suitable for music recording but is very useful for keeping generations of files. DVDs have between five and ten times the capacity of CDs.

DVD RW Solid state backing storage

Physically the smallest form of memory and used as removable storage. More robust than other forms of storage. More expensive than other forms but can be easily written to and updated.

DVD-RAM

Same properties as DVD RW but quicker access and data can be overwritten more easily. Similar to floppies in nature but has 3000 – 6000 times more storage and uses optical technology

Blu-ray

Capacities of 25Gb, 50Gb and 100 Gb. Used for storing films (movies).25Gb equates to 2 hrs HDTV, 13hrs standard definition TV. It is possible to playback video on a disc while simultaneously recording HD video. (Will be) used for storage of PC data

HD DVD

Capacities of 15Gb, 30Gb and 45 Gb. Less capacity than Blu ray. Used for storing films (movies). (May be) used for storage of PC data

Memory sticks/Pen drives

Can store up to many Gb. Used to transport files and backup data from computer to computer – often referred to as USB Flash Drives.

Flash memory cards

Used in digital cameras, palmtops, mobile phones, MP3 players

Minidisk

Magneto optical method or writing data. Used for storing music. Can store up to 140Mb

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excel spreadsheets on storage devices Portable communication Devices: mobile phones, portable dvd players, portable media players, GPS, satnav, PDAs, Bluetooth. Know the range of portable communication devices, suitable uses and advantages and disadvantages.

Communication Device

Uses

Mobile Phones

By using electromagnetic radio waves they are now widely used all over the world for business and personal use. They are especially useful in remote areas, such as in deserts, thinly populated areas and at sea. With text messaging they are especially good at send urgent messages without disrupting the person receiving the call or requiring handsets switched on.

Portable DVD players

They are mainly used for personal use but can be very useful when travelling for briefing or entertainment uses.

Portable hard disk players

There is little difference between this and a USB flash or pen drive. It attaches to a PC or Laptop and is largely used to play movies. Very useful if you want to take a video presentation to a conference! The link opposite examines one such device on the market now

Portable media players such as MP3 players

Again, these media devices are for entertainment purposes although recorded messages and audio information can add to the use.

Global Positioning Systems (GPS)

Global Positioning System (GPS) devices are a relatively new navigation invention, considering we've been using compasses and maps for hundreds of years. Used by the military for years, the government opened up GPS satellites for civilian use in the 1980s.

Satellite Navigation Systems

This really an alternate name for GPS just covered. Theye are often abbreviated to SATNAV

Personal Digital Assistants (PDAs)

The PDA computer is similar to a standard desktop computer because they share many of the same parts. Learn about the PDA computer and PDA processor... of the PDA, and it coordinates all of the functions according to programmed instructions. Unlike desktop PCs and laptops, PDAs use smaller, cheaper...

Bluetooth Devices

When you use computers, entertainment systems or telephones, the various pieces and parts of the systems make up a community of electronic devices. These devices communicate with each other using

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a variety of wires, cables, radio signals and infrared light beams, and an even greater variety of connectors, plugs and protocols. Handheld computers

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a term for the small computer and can incorporate all devices in this list –. All such devices have the benefit of portability and such technology is developing rapidly.


Section 2: How organisations use ICT 2.1

Control Systems

Keywords: microprocessor, physical conditions, air-conditioning, refrigeration, sensors, pre-set values, ADC, actuator, compressor, LEDs, buzzers, valves, pumps, robots, arms, end-effector, programming, intensive care, surgery, process control, batch, discrete, continuous, PLC, PID, EWT.

Control Systems are made up of software and hardware that controls other equipment. They can be "dedicated" systems that perform a set of pre-programmed instructions, or computer controlled ("dynamic") systems that react to input from sensors. Most control systems use feedback loops to tell them how to behave. This is when information from a sensor (e.g. temperature sensor) is used to decide how to use an output device (e.g. heater). The output device will have some sort of effect on the next reading from the sensor - e.g. switching on the heater will raise the temperature at the temperature sensor.

Compressor • Cool low-pressure gas into hot high-pressure gas • Gas moves through the condenser outside the building •

Gas cools down into a

liquid • Liquid flows through the expansion valve • It evaporates into a cool low-pressure gas •

As liquid changes to gas, it absorbs heat from the inside of the building. •

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Fan blows air across metal fins (which have chilled as a result of heat being absorbed)

The room cools down.


Central heating

•

An ADC (Analogue to Digital Converter) is used. • The microprocessor controls separate actuators: 1. Opens the valves 2. Switches the pump on 9


Car Manufacture

End effectors

What do they use in industries and why? ∞ They use robot arms ∞ It consists of seven metallic sections with six joints. ∞ Each joint is controlled by a separate stepper motor. How does the computer control the movement of the arm? It uses different ‘end effectors’. This allows for a variety of jobs to be done. The ‘end effectors’ are attached at the end of a robot arm. Initially the programmer guides the arm step by step. This is usually done be actually physically holding the arm.

1. Cameras in order to inspect work 2. Welding guns 3. Grippers which allow for parts to be picked up easily. They have built-in pressure sensors. 4. Vacuum cups i.e. electrical parts 5. Drills 6. Screwdrivers 7. Spray guns 8. Sanders

These arms contain sensors which allow them to transmit data back to the computer. The computer then stores the exact order of movements as a program in its memory. You could also move the robotic arm by using a remote control. A robot arm is much more accurate than a human The running costs are comparatively lower Robotic arms do not get tired Robots can be used continuously

Intensive Care The patient is monitored by sensors. These sensors measure: 1. Blood pressure 2. Pulse rate 3. Body temperature The computer it pre-set with values. So the sensors take in the above mentioned variables and compare them to the pre-set values, if the measured value is outside the pre-set value range, an alarm is set off by the computer. The computer allows the doctor to monitor several patients at the same time.

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Surgery •

It involves robotic arms + cameras inside the patient’s body.

These robot arms and cameras are much smaller than normal.

Usually the end effector is a scalpel.

The surgeon wears a type of goggles which allow him to see inside the patient´s body. The surgeon then controls their hand by putting their hands into a console. Their hand movement is then imitated by the robotic arms.

The work is done more accurately

The patients recover more quickly because large scale operations are not necessary.

The patient does not occupy the hospital bed for long.

Process Control •

This is when computers/microprocessors are used to control a process.

Few examples: × Oil refining × Chemical processing × Car manufacture × Temperature control Type of Process: Batch. This is used when a specific amount of raw materials are combined together + mixed for a certain length of time For example: -

In pre-packed meals: the amount of each ingredient that is added is controlled by a computer. The length of time it cooks for and the temperature is also computer controlled.

-

It is used to produce relatively small amounts of product per year.

Type of Process: continuous. •

This is a process that never appears to end.

For example: Maintaining the temperature of a confined environment. Paper machines with continuous paper output onto rolls. It is used to produce very large quantities of product per year. 11


Type of Process: Discrete •

This is only used when a specific item is produced. It is like an on/off process.

For example: Manufacturing of cars; computer control used when fitting the wheel. The wheel is fitted, next car comes and the same robot fits the wheel in the same position. What are most process controls overseen by? •

By a Programmable Logic Controller (PLC)

It is the type of computer that is only used for one purpose.

It can accept both analogue and digital Inputs.

Then a set of logic statements are used to compare the input with the input pre-set value. Dependent on the result the output device is activated.

It is usually found in industrial processes.

Once it has been programmed; there is no further input from the user. How can you program a PLC? •

By using a Proportional-Integral-Derivative (PID) algorithm.

They are used with closed-loop systems.

What is a close-loop system? •

It is a system in which a physical variable is continuously being monitored.

The purpose of the PLC is to make the input value equal to the pre-set one.

PID is the BEST way to do this. It is found in many versions of control systems. For example washing machines.

EWT: Embedded Web Technology •

This technology combines the Internet, the worldwide web and the real time systems into one technology for controlling embedded systems.

What is an embedded system? It is an integration of microprocessors, input sensors, output actuators and the software needed to control them. The embedded software enables the user to adjust and control oven temperatures using a mobile phone or PDA or laptop computer.

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ADC (analogue to digital converter) Most sensors take analogue measurements. This means the output changes smoothly from one value to another. All computers need digital data in order to process it further. Digital data only has two values either 0 and 1 or On and Off. In order for the data collected by the sensor to be handled by the computer, it needs to be converted from an analogue signal to a digital signal. To do this, a special piece of hardware is needed called an analogue-to-digital converter or ADC. The ADC is connected between the sensor and the computer’s input-output port and it is called an ‘interface’. In the diagram below, the ADC is providing the input to the CPU.

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2.2

Working practices

Keywords: teleworking, portable communication devices, broadband, VPN, PDA, videoconferencing, remote working, RAS, LAN, WAN, VOIP, instant messaging, faxing, electronic faxing.

Changing work patterns Technology has led to a huge change in working hours. People who traditionally only worked 9-5, Monday to Friday, may now find that they have to work evening shifts, night shifts or weekends in order to provide the service that customers expect. This can leave them feeling tired and stressed. Customers expect to be able to call their bank or building society in the evenings, sometimes even at 3am someone has to be there to answer the telephone. Customers expect to be able to buy their goods online at midnight - someone has to be there to ensure that the website is working correctly and that the servers don't have any problems. Customers expect goods to be on the supermarket shelves when they want them. Lorries have to be driven night and day to ensure this and so route planners need to be available to replan a route when a delay occurs. With ICT, we are gradually becoming a 24 hours a day society. Inevitably, since ICT can automate many jobs and do them not only faster but also more accurately, then many of the old jobs have disappeared. We no longer have typing pools full of secretaries, there is no need for an office full of clerks to calculate and count out weekly wages, there is no need for printers to manually typeset the newspaper pages. Many hundreds of thousands of people lost their jobs as these changes happened. Job loss is not pleasant; it affects peoples' self worth and creates all kinds of stress and disruption in families and society in general.

Skilled workers needed Technology drives much of business these days and so most companies want workers with the basic skills to use it - typing for example or being able to use email. This is called 'computer literacy' and it is becoming as important as reading and writing in the job market. This gap between people with computer skills and those with none is part of the 'digital divide'.

Teleworking The introduction of ICT has led to a big change in the way some people work. Because of the Internet and the ability to communicate with the company network from anywhere in the world, many workers now work part time or full time from home. Telework is not a specific job in itself, it is a method of working, which is usually taken to mean doing your job from home.

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There is no legal definition of teleworking, but the essential feature is the use of information technology to enable people to work away from the office. This could apply to people working full time or part-time at home, those dividing their time between home and the office, and mainly mobile workers who use their home as an administrative base. Telework is growing. Over 7 million people in the UK now use IT to help them work away from the traditional office environment, either full time or part time. It is estimated that the average person spends around 4 hours travelling to work each week. That is a lot of time sat in a car!

Teleworking advantages for the employee Work the hours you want You may be able to work the hours you want, so if you like to get up at 6am and finish by lunchtime, you *may* be able do that. Likewise, if you are a sleepyhead, you can stay in bed until noon and work until late in the evening. You can take a break when you want one. You can stop to chat to a friend if the phone rings or watch something on the TV. On the other hand, if your company is expecting you to be available during office hours, then you may not have as much flexibility as you think - for example you may have a customer-facing job and so you need to be at the end a telephone line during normal office hours.

Organise hours around family needs It makes possible to work around family commitments, for example dealing with young children or elderly parents.

Save traveling time and costs It saves a huge amount of time that would normally be spent traveling to work. There is no need to spend an hour or more each morning and evening stuck in traffic jams. You save the cost of petrol that you would normally need to travel to work and also the cost of car parking tickets.

Environmental benefits You help reduce your global warming carbon footprint by not burning up fuel, on the other hand you will need to heat the home office and use extra electricity so it may not be as effective as it first appears.

Collaborate with others Working over the internet means that it is possible to collaborate with other people around the world without having to meet in person. For example, you may be an artist working for a magazine, your job is to create images to support stories in the magazine. So you collaborate with the authors around the world who are writing the stories. There is no need for you to be physically together - each of you send your contribution to the magazine where the editor puts the story together (even the editor could be working from home!).

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Short summary 

Flexible working hours

Work around family obligations (young children, elderly parents)

Can take a break during the day (walk the dog or catch the news)

Save lots of time on traveling to and from work

Save lots of fuel and parking costs

Saves on global warming to some extent

Collaboration is easy with internet connection

Teleworking advantages for the company Smaller premises With some of their employees working from home, they do not need as much office space. Nor do they need as much parking space workers

Less energy With smaller office premises comes less energy-use so reducing costs and reducing carbon footprint. Although the worker at home will offset this to some extent as the company will need to pay for some the energy used at home.

Could work around the clock When it is 5pm in the UK it is mid-day in New York and the day is just starting in California. So if you are an international company, teleworkers could be located around the world to carry on working 24 hours a day if need be. For instance, a finance company could have stock brokers working from home in different time zones to deal with the stocks and shares 24 hours a day.

Can use skilled employees far away from headquarters Many skills are quite rare. For instance computer aided design engineers with specialist skills. Say an engineering company in the UK wants a CAD designer for a specific project. They post the job on a freelance web site. Maybe an engineer in Brazil sees the posting and offers their skill to the UK firm. Contracts are agreed, file formats and deadlines are set, and so the project begins. Without teleworking this kind of 'virtual team' would not be possible.

Keep a skilled worker from leaving Another common situation is that an employee may have to leave for a few months - having a baby perhaps or some maybe some medical problem. If may be possible for that person to work from home. Everyone wins - the teleworker can carry on from home and the company does not lose a valued employee.

Can use a dispersed work force Many companies have their sales force located all around the country or even the world. It makes no sense for those people to come to the office every day. They could do their jobs just as easily based from home. For example, consider a company that has dealers in the south, west, east and north of England. They 16


employ a 'regional manager' to look after each region. Each regional manager works from home, maybe only going to HQ once a month for a sales meeting. Meanwhile they keep in touch by phone and email.

Short summary 

Smaller premises

Less energy use

Work around the clock

Use skilled labour from anywhere

Retain staff who do not want to leave (but have to)

Dispersed work force

Disadvantages of teleworking: Employees For all the benefits we have mentioned for both the individual and the company, teleworking is by no means as popular as people predicted. So why not? Why do people still sit in traffic and why do companies still keep staff in offices? The answer lies in the disadvantage of teleworking.

Issues for the individual Always on call You might feel you are always 'on call'. Because you are at home, the office might think that you are always available to do just a bit more work. It would need some sensible agreement as to when the company can call you up (and when they can't)

Harder to separate work from home life You may have problems at home sometimes and you may have problems at work sometimes. Many people prefer to keep these things separate. Working at home makes this separation more difficult. Using a specific room as an office at home may help, but many people do not have the extra room.

Work even longer hours Without the definite start and stop times of 'normal' work, it is easy to slip into the habit of working for too long. For example, checking work emails all the time. Good time discipline is needed to keep to standard hours.

Can be harder to be motivated There can be a lot of distractions at home and you might be tempted to do other things rather than work

Work social life Working is not all about getting your head down all the time. There is a lot of fun and banter to be had with your work colleagues as well. It can feel lonely at home, especially if the rest of the family is out of the house during the day.

Career prospects Being away from the office means you may miss out on career opportunities. For example some important project may come up that could lead to promotion. 17


Disadvantages of teleworking: the company We have discussed some issues for the individual teleworker. There are also some disadvantages from the company's point of view

Company disadvantages Keeping an eye on progress It is much harder for managers in the office to keep track of progress with teleworkers. For example the managing director might ask the local manager for an update within the hour. They will then have to put the calls to the teleworkers to find out what is going on. Even more stress if they can't get in touch with everyone in time.

Meeting deadlines Many jobs involve critical deadlines. For example a newspaper has to go to print by a certain time. Any teleworking journalists must have the discipline to deliver their story on time, every time.

Keeping up standards With a scattered workforce it is harder to keep everyone up to the same standard. One solution is regular training sessions for teleworkers to keep up to date with the latest developments. This is especially true for professions such as electronic engineering and software design where technology changes within months.

Keeping up a good team One of the critical skills of a manager is to run and motivate a good team. This is done through face to face encouragement, mentoring, support and so on. Doing this from a distance is much harder.

Maintaining the company ethos Many companies have a certain way of doing things. When everyone is working at the same place, this company culture is easy to share. People take note of the attitude of the rest of the team. But with perhaps freelance teleworkers, this is not easy to do.

Health and Safety, Insurance Employers are liable for the welfare of their workers even if they work at home. Checking that everything is as it should be is not as easy compared to having everyone in the same place.

Data security and confidentiality Companies want to keep their customer details safe and secure (Data Protection Act) along with keeping critical financial data such as contract terms away from the competition. Strict, professional-level encryption and physical security is needed. One solution is for teleworkers to store everything on company servers at HQ with nothing getting stored at home. Virtual Private Networks (VPN) is one way of doing this.

Maintaining equipment Many companies have IT staff who apply the latest software patches to every workstation in the office, remotely. This is not so easy with teleworking. Also if a hardware fault develops, it is harder for a technician to fix it if the machine is at home.

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Fax A Fax (short for facsimile) machine transmits a copy of written and graphical information via the telephone network. It works in a similar way to a photocopier, except the copy is transmitted to a distant machine via the telephone network. Each Fax machine has a telephone number, this may or may not be shared with a telephone. Faxes are widely used in business offices because they make it very easy to transmit invoices, orders, rough drawings, copies of contracts and so on. It is now possible to send and receive Faxes by email. The email is sent to a service company who then converts it to a normal Fax message and sends it to the telephone number you specify. It also works the other way around, you can have a fax-to-email service where someone sends a fax in the usual way of calling a telephone number, but at the other end it get converted into a pdf (acrobat) document that is then forwarded to an email address.

Electronic faxing Internet fax, e-fax, or online fax is a general term which refers to the use of the Internet to send a document fax, rather than using only phone networks (traditional faxing) with a fax machine. The term "Internet fax" encompasses "web fax" and "email fax," along with VoIP fax, which refers to the use of Voice over Internet Protocol to send a fax. However, Internet fax should not be confused with IP fax. Depending on the specific method/implementation (see below), advantages of using the Internet can include      

no hardware; no software no extra telephone line required for fax paperless communication, integrated with email the ability to store encrypted faxes online securely the ability to send and receive multiple faxes simultaneously a reduction in phone costs, along with lower costs than traditional fax

 the ability to send and receive faxes from any location that has Internet acces  the ability to send and receive faxes from mobile phones, smartphones and tablets

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Audio / Video and Teleconferencing Teleconferencing allows people in different locations to talk to each other as a group. This is also known as an Audioconference or simply a 'Conference Call' It works by each person 'logging on' to the conference call. When you switch on your conference call device and enter your user ID number, an automatic voice saying something like "Mr Jones has joined the conference" is broadcast. Everyone says hello and carries on with the meeting. Video conferencing is similar to teleconferencing except that people in the meeting can now see one another because video cameras are used to send live images over telephone lines. Now that broadband is offering good speeds, video conferencing with friends and family is also becoming popular.

Video conferencing pros and cons

Business-level conferencing facilities can be expensive There is no need to spend time and money travelling to meetings

and everyone who is going to attend the meeting needs access to suitable hardware and software. Although domestic conferencing is virtually free as long as you have a computer and a fast internet connection.

You can have a 'meeting' with people from

A very reliable, fast data link is needed. Many companies

many different offices /countries without any

hire a connection specifically to allow video conferences to

of them having to travel

take place

You can see people as well as hear them. This means you can see their body language which you can't do with a telephone call.

Even with a fast connection, there might be a slight delay between responses. Especially from one side of the planet to the other.

You can all view a document on the screen at the same time. People can work together and add their ideas. The document can be emailed to all of the people at the meeting

If the hardware breaks down for any of the participants, they cannot 'attend' the meeting

later on.

Ideas and knowledge can be communicated

People could be in different time zones around the world.

between all those at the meeting very

This might mean that some people have to stay up through

quickly and responses gathered. Video

the night in order to attend the meeting.

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conferencing is good for 'brainstorming'.

Video conferencing is an excellent way of

The video camera might not be able to see all parts of the

keeping in touch with friends and family,

room at the same time. Some people might not be easy to

even if they are in a different country.

see at the meeting.

There is no substitute for a face-to-face meeting in getting to know someone.

Online communications: VoIP The internet was originally designed to transfer data from one place to another. However, 'data' can be anything you want represent - including speech. This what VoIP is about. It stands for Voice Over Internet Protocol. You speak into a microphone connected to your computer and the VoIP software you have installed converts it into a format that can be sent over the internet. The person receiving the call must also have VoIP application running in order to listen. There are also specially designed telephone handset for VoIP so it is just like using a normal telephone. Probably the most well known VoIP service is Skype.

Instant Messaging This is mostly a text based service, where one person types a message and the other person immediately sees it pop up in their IM (Instant Message) window. Groups can also be set up so that a number of people can chat to each other whilst online. Each person must have an 'Instant Messaging' (IM) client open on their computer. The way it works is very similar to email, because both IM and Email client software need to connect to a server in order to work. The difference between email and Instant Messaging is that the IM window shows the message almost as soon as it is typed - no downloads are required. This kind of service is used by business people to help keep in touch whilst on the move. Imagine a work colleague is at the airport waiting for a plane connection, they can use Instant Messaging to 'talk' to colleagues in the office - it is a good way to keep on working (and avoid the sheer boredom of waiting for a plane!) despite being away from the office. 21


It is also used at home. For example, you are online doing your usual stuff on the Internet, but you have an IM window open because friends and family are also online. You chat whilst each of you are online. Another common use of IM is with online gaming. Perhaps twenty of you have gathered together in the online game and now you are arranging what needs to happen next. Each person fires up their IM client and joins the group to chat about tactics and so on.

Instant messaging pros and cons

Allows you to chat in 'real time'

As it is immediate, you have no time to reflect on the message you are

to other people who also have

sending, unlike an email where you can review the draft before

an IM client.

sending.

In order to provide a free service, the IM providers send adverts and popup windows to each person. If you want to avoid this, you need to pay for a 'premium' service.

Unless you set up your IM client carefully, anyone can send you a message - not always a good thing.

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2.3

Use of ICT in advertising

Keywords: product, business, service, websites, web authoring package, hyperlinks, popups, directories, multimedia, flyers, posters. Media used for advertising: •

Billboards

Cinema advertising

Flyers

Magazine

Newspapers

Posters

Radio

Video games

WWW

Types of advertising: Product advertising -

A single product – can of coke

-

Type of buyer ?

-

Identify media

E.g. Kids soft drink advertised during afternoon television hours. Business advertising -

Make company name familiar

-

Type of customer?

E.g. Expensive shoe company will advertise in high class magazines. Service advertising

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Insurance

Government

Tourism

Banking

Education

Social services


Methods of advertising: 

Websites Advertising on the internet is a recent development. Its relatively cheap for a company to advertise through its own website. Web developers create the websites using web authoring packages i.e Dreamweaver Website should ideally: Contain multimedia content Interactive Easily to navigate – hyperlinks Highly visible to search engine

Flyers A single page leaflet. Used by individuals and small business Produced quickly using basic desktop publishing. Cheap way of advertising in the local community.

Posters Normally A1+ size Wide variety of advertising uses. Using large-format ink-jet printer or plotter.

Internet Advertising 

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Many advertisements on Web sites are banner ads •

Originally in the shape of a long rectangle

Require the user to leave the current site

Other ad types •

Pop-over ads open a new window on top of your current window

Pop-under ads open a new window underneath your current window


2.4

Use of ICT in teaching and learning

Keywords: CAI, CAL, CBL, CBT, CMC, CAA, instant-messaging, formative assessment, summative assessment, online marking, OMR, record keeping, conditional formatting.

CAL is where someone makes use of a specially designed software application in order to learn about a subject or practice a new set of skills. Computer Aided Learning is not only used in schools but is also widely used in industry to teach employees about the things they need to know about. There are many features included in a CAL application: > You are able to move forward and backward through the course at your own pace. > You are able to stop at any point and return to that point later. > There will be some form of testing and scoring and feedback will be provided to you on your progress. > You are able to continue retaking the tests until you pass or are sufficiently confident with your skills. CAL applications or courses usually make use of various multimedia such as videos and sound files

What is the most important part of CAL? The INTERNET! Why? It allows the students to research + investigate ideas. What ICT devices are used by teachers (making their teaching CAL)? i.

Computers

ii.

DVD players

iii.

Interactive whiteboards

iv.

Multimedia projectors

v.

Overhead projectors

vi.

televisions.

vii.

CAL and CBL (Computer-based learning) ďƒ methods in which the teacher is not replaced but they are used to aid the teacher and to improve the learning experience for the student.

viii.

The teacher controls the learning experience.

ix.

CAL or CBL are only introduced after an assessment of the current teaching methods.

x.

It should be used with textbooks, worksheets + other media.

xi.

The CAI will give a pre-test to the student to determine at what level they should start. In a good CAI package, this assessment is straightforward.

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xii.

Navigation is easy for the student.

xiii.

Games and quizzes make it more enjoyable.

xiv.

This software also keeps track of the students progress.

xv.

The use of spreadsheets has increased as it is being used for:

xvi.

Store examination marks

xvii.

Predicted grades

xviii.

Targets

xix.

Attendance records

CAA: (Computer-aided Assessment) There are two types of testing: Formative: this is when the answers of a specific question are collected to form a judgement on specific progress. Summative: this is when questions are asked and answers are recorded. Current situation: candidate’s papers are scanned into a computer system + examiners can log onto the system and then mark the papers on the screen.

Online exams The traditional exam is very labour intensive and slow to mark. Students are normally given a paper based exam papers with the questions, which they then answer with pen and pencil. For external exams such as GCSEs and A Levels these papers are then sent away to be marked by an examiner. There are numerous problems with paper-based exams:    

they can be slow to mark by hand the student's writing might be hard to read even though there are mark schemes each examiner will mark slightly different from another printing and storing the exam papers is costly and takes up space in the school.

Outside of education there is a move to online computer tests. For example, the UK driving test is now a computer based multiple choice test. Within education the uptake of computer based testing is slow. Some courses such as the ECDL can be done using a computer but we are still a way off allowing students to take their GCSEs and A levels electronically. However, some schools in Europe are more forward thinking and many of their students take all examinations online using a computer. 26


Online computer tests Each question is presented on screen along with a set of possible answers (multi-choice). The student then selects their answer, either by mouse or touch screen. The advantage of taking an exam this way is that it is very fast to mark and it does not involve a lot of paper which may get lost or damaged. The disadvantage is that it cannot deal with drawings very easily or with long essay type answers. But for simple tests, it is very quick and easy to set up and mark. CMC (Computer-mediated Communications) What does it consist of? E-mail: used to send completed tasks to a teacher. Instant messaging Chat rooms

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2.5

Use of ICT in publishing

Keywords: newspaper production, e-mail, word processing software,

Printing industry

Correspond ents send in their stories from the location of the story – done by email

Received at the editorial staff- the collect and send the stories to the newspaper journalists as the main office.

Page layout of the newspaper is created

The process is then completed when the document has been edited to remove any mistakes.

Daily newspapers used to be printed on this old fashioned printing press. Printing used to be a very manual, skilled job with a master printer taking years to learn his craft. Each word had to be created by 'type setting' by hand. This meant picking each individual letter and creating sentences (backwards). Once the type setting for the page was created, each page would be printed off in a large batch before the type setting would be changed for the next page. In 1985, photo-typesetting was developed and it made it possible to automate the printing of newspapers and books. This is the modern day printing press. Nowadays, newspapers are written by journalists who use a computer and a desktop publishing system tied to the newspaper's network... The digital layout is then transferred to the printer and newspapers are printed very quickly in their thousands.

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2.6

Use of ICT in time management

Keywords: projects, targets, prioritising, planning, decision-making, meeting times, calendars, arranging workload, research & development projects, construction project management. ICT projects are usually a major undertaking for any company. They can involve huge sums of money, months even years of work and the involvement of many staff, who, while they are involved on the project are not available to do their 'normal' role within the business. Although many IT projects are successful and companies get the system they need, unfortunately, due to a variety of reasons many project fail completely or don't deliver the system that was originally promised. This could be because of:      

poor planning poor time management over optimism or unrealistic time frames poor budgetary control insufficient budget poor communication within the project team or with users

A project which fails to deliver ultimately wastes valuable time, money and company resources. If the project has taken many years the company can be left at a disadvantage against their competitors who have probably introduced similar systems. It is essential that any company about to embark on a new IT project does everything possible to ensure the successful outcome of that project.

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30


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2.7

Use of ICT in data management

Keywords: database, DBMS, sequential files, ordered, unordered, master file, transaction file, indexed sequential file, random access, relational database systems.

File Access A serial file is one in which the records have been stored in the order in which they have occurred. They have not been sorted into any particular order. An example of a serial file is an unsorted transaction file. A shopping list is an example of a non-computerised serial file. Items are appended to the list when that item runs low. Serial files can be stored on tape, disc or in memory. A sequential file is one in which the records are stored in sorted order of one or more key fields. Disadvantages of a Sequential File 1. You can only add a new record at the end of the file 2. If a record needs to be replaced it must be the EXACT same length as the original 3. A record can only be updated if the data item used to replace the existing data is the same length as the original. Processing of a sequential file is slower compared to other files. How? How do you process records? • •

You need to read through each and every record until you get the one you want. Only recommended for applications where most/all the records are to be processed at one time.

Functions in a Sequential File  Adding records -- > easy  Amending + Deleting -- > not so easy.  If it is an unordered sequential file  amending and deleting are fairly difficult  If it is an ordered sequential file  amending and deleting are sort of easy. This is done with the assistance of a transaction file.

Computer reads the first record from the transaction and the master file. If the ID doesn’t match (In this case it does), the computer writes it to the new master file

An example of a sequential file is a sorted transaction file. A class register is an example of a non-computerised sequential file sorted on surname. Each record of a file has a key field which uniquely identifies that record. 32


An index consists of keys and addresses (physical disc locations). An indexed sequential file is a sequential file (i.e. sorted into order of a key field) which has an index. A full index to a file is one in which there is an entry for every record. Indexed sequential files are important for applications where data needs to be accessed.....  

sequentially randomly using the index.

An indexed sequential file allows fast access to a specific record. Example: A company may store details about its employees as an indexed sequential file. Sometimes the file is accessed....  

sequentially. For example when the whole of the file is processed to produce payslips at the end of the month. randomly. Maybe an employee changes address, or a female employee gets married and changes her surname.

An indexed sequential file can only be stored on a random access device eg magnetic disc, CD. A Random File is a file where the records are placed at an address arrived at by a calculation performed on a key field. This calculation is called a hashing algorithm. Access to records follows the same pattern...  

use the hashing algorithm on the key to find the address of the block where the record is stored. look for the record at the address. If it is not there follow the pointer to the overflow area.

Access to records is extremely fast. A random file would have to be stored on a direct access backing storage medium eg magnetic disc, CD, DVD Example : Any information retrieval system. Eg Train timetable system. • • • •

Banks use sequential access systems in order to process cheques. This will be very useful especially in online banking. Index sequential files are used with hybrid batch processing systems- employee records. This allows for direct access when an individuals record needs to be seen. Records held sequentially allowing serial access when producing a payroll.

Network Database Management System (DMS) • • • • •

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Overcome the faults of the hierarchical DMS Many organisations now use a distributed database system. Data is stored on computers that are then linked by a LAN/WAN. Data in the database is duplicated several times, so it is unlikely to loose the data and it also gives the users faster access times. To a user it seems to be a single system


Database control: DBMS We have discussed the structure of a database as consisting of one or more tables, each of which contain records and fields of various data types. The next requirement is to have a system in place that can act upon that data as well as creating and maintaining the database itself. This is the role of the 'database management system' usually referred to as a DBMS. A DBMS is an application designed to control all aspects of a database. The DBMS will have a command language. This includes command statements for:        

Creating an empty database Deleting an entire database Creating and deleting tables Inserting new records into tables Updating and deleting records Being able to extract data sets Being able to produce reports that summarise the data Being able to process the data to create new data

There are many database management systems that are either commercial products or free open source applications. Examples include Name

Comment

MySQL

A very popular, free open source system, widely used on web sites

Access

Included in some versions of the Microsoft Office suite

Base

Part of the free Open Office suite

Oracle

A multi-user enterprise level database management system. Widely used in industry

There are database management systems available for every pocket and complexity Advantages of Relational Databases 1. Data not repeated – storage capacity not wasted. Comparing this to a flat file database, in which data is repeated. 2. Data retrieval is quicker. If the data is repeated, hackers will have greater ease in accessing the data. Relational databases reduce this risk. 3. They also allow room for expansion

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2.8

Payroll applications

Key words: batch processing, magnetic tape, inputs, processing, outputs, master file, transaction file, key field, temporary, automated, updated, payslips, reports. •

They involve batch processing

The files are stored on two separate magnetic files

This obviously then means that there will be two types of data files involved

Master file – containing data about the workers:

Employee number ( This is used as the PRIMARY KEY; data is stored in order of this)

Name

Contact details

Rate of pay

Pay received

Transaction File – is a temporary file; containing data that can change from month to month. •

Contains details of # of hours worked + any overtime + employee number.

Details of any new worker or any worker whose details have been changed.

Records from old master file are read and are updated using calculations, deletions, addition or amendments

Old Mast er File New Master

File

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Transaction File

Update (this involves calculation of employee’s wages using the hours worked from the transaction file)

Reports (these can consist of : a) Financial reports b) Error reports c) Payslips


Payslips: •

Payroll software  report generator facility

1. Information on employees of company/ or department 2. Information on employee salary 3. NI(National Insurance) contributions for all employees 4. Total NI contribution paid to tax authorities. 5. Income tax Amount of money paid to each bank where employees have an account

Exception Reports •

These are reports of certain validation rules. For example: – Employee earning an unusually large amount of money – Employee that has been on emergency tax for a long time. – 2 employees with the same NI number.

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2.9

Technical and customer support

Keywords: telephony server, headset, telephony cards, communications switch, CTI, IVR, 1st party & 3rd party software, utility companies, script, cost-savings, flexibility. What actually happens in a call centre? 1. Large office space 2. Has about 100 operators 3. The operators take and respond to requests for help 4. Operator sits at a computer. 5. This computer is connected to a telephony server by the company’s phone line. 6. Each computer has an integrated headset 7. The operators computer MUST be fitted with a telephony card 8. Each computer is linked to a telephony communications switch There are many operators accessing the same line at the same time… what type of software is required? Phone calls are processed by the IVR (Interactive Voice Response). - The IVR does not require any human assistance. It is an automatic service that can be accessed by the caller. The caller then connects to the system database using the IVR software.

Computer Telephony Integration (CTI) Software •

Integrates all aspects of the system together.

CTI sends commands from the operators computer to the telephony server

Operators computer has NO direct connection to the phone.

Any computer can control any phone in the telephone system.

Allows the computer to direct the call to : •

An appropriate operator

Another solution

The system MUST also have the ability to transfer calls to a person with the appropriate expertise. (Can’t direct a call for the Human Resources Department to the Medical Centre Department 1. It combines data and voice input to the system 2. Displays the caller’s number 37


3. Allows for multiple dialling techniques: a) Fast dial b) Preview c) Predictive dial What are the two forms that CTI works in? 1. First Party Control: – This allows the operator to have direct connection between their computer + phone set. – This allows the operators computer to control the functions of the operators phone. – Only suitable for the smallest of call centres. 2. Third Party Control: – Requires a dedicated telephony server to connect the telephone network and the computer network. – Operators phone communicates directly with the server, allowing the server to control all the phones. – Any computer can be used to control any phone in the system; allowing supervisors to intervene if the call proves to be too complex for the operator. Examples of business’s using call centres: 1. Utility companies : Use call centres to give customer support. Helping the customers who want to pay for their bills or change details of their account. 2. Mail order catalogues : Helps customers in the form of payments or account information. 3. Computer hardware and software suppliers: offer technical expertise and help customers whose computers are not operating as they should. Advantages: •

Can pay employees lower wages

The cost of buying/renting premises is lower

Calls can occur at a more suitable time (it may be 7 pm in one place but may be 9 am at the other place)

Company does not have to pay higher wages for unsociable times.

Disadvantages: •

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Difficulty in understanding different dialects


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Workers abroad may be less flexible in their approach (they will have a ‘script’ and they will stick to it, this script consists of possible advice that can be given to the caller depending on their response.


2.10 Art & Design work •

•

Most companies that are in the design sector, use computers with a large storage capacity These companies usually have an appropriate graphics software involved i.e. image-editing software. Why is it used?

To alter the appearance of images that have been imported into the software input devices.

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1. 2. 3. 4. 5. 6. 7. 8. 9.

Crop Rotate image Flip image Fill parts of image with colour Look at image in 3D Remove scratches from photos Draw lines and other shapes Add text in different fonts Access to clipart


Section 3: Impact of ICT on society 3.1

Online services

Keywords: Internet, broadband, transactions, government services, buying, selling, banking, shopping, Internet & WWW.

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42


43


44


45


46


Internet Banking It is now very common for bank customers to access their bank account from home using on-line banking services. Customers use a computer and connect to the bank’s secure (encrypted) website where they login (usually with a username and password) Customers can use the on-line banking system to... 

Check the balance of bank accounts

Pay bills

Transfer money between accounts (using EFT)

Apply for loans, or other services

Compared to travelling to your actual bank, Internet banking has a few advantages...

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More convenient - can be used 24 hours a day, 7 days a week

Saves time and money since you don't have to travel anywhere to use it


Data can be downloaded and analysed (e.g. in a spreadsheet) which can help with planning budgets

But there are some disadvantages too...

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Requires you to have a computer and Internet access to use it

Some people prefer to speak to a person (personal service)

If your account is hacked, or your username / password is stolen (e.g. if your computer has malware) money could be stolen from your account


Booking Systems Computers are often used to book (reserve) air flights, seats in the cinema, rooms in a hotel, tables in a restaurant, etc. In all of the above examples, there are a limited number of items (seats on a plane, rooms in a hotel, etc.) which need to be allocated. It is very important that any booking system prevents the same item being booked twice (doublebooking).

So How do Booking Systems Work? If we were talking about a single, small cinema, where you had to queue up to buy tickets at the front door, the reservation system would be very simple: We could just use a piece of paper and tick off seats as they were reserved. However, most booking systems are much more complex than this. A typical booking system must cope with booking requests from many different sources, all arriving at the same time. For example, flights can be booked by customers online, by travel agents in dozens of different offices, by businesses, etc. How do booking systems manage all these bookings without making any double-bookings? All Booking Systems are Real-Time The Key to all booking systems is the fact that they are real-time systems. A real-time system is one where every input is processed immediately, so that the resulting output is ready before the next input is processed. In the case of a booking system... 

The inputs are booking requests

The processing involves checking if bookings are possible, and if so making the bookings

The outputs are booking confirmations / rejections

Because a booking system is real-time, when a booking request arrives, the previous booking has already been fully processed. This is what prevents double-booking. An Example... Imagine that two people are using an airline's website to try and book seats on a flight. Both

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people try to book seat 38C and the same time... Even though the booking requests are made at the same time, one request will be received by the airline's computer just before the other (since requests come into the system through a 'queue') This is what happens: 1. Input: Please reserve seat 38C 2. Process: Has seat 38C already been booked? No... so book it 3. Output: Booking confirmed for seat 38C 4. Input: Please reserve seat 38C 5. Process: Has seat 38C already been booked? Yes! 6. Output: Booking rejected You can see that the first input is fully processed before the next one. So seat 38C doesn't get booked twice.

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3.2 online services and employment Keywords: unemployment, new opportunities, robots, program, automation, call centres, programmers, help desk. - It makes possible to work around family commitments, for example young children or elderly parents. - You can take a break when you want one. You can stop to chat to a friend if the phone rings or watch something on the TV. - It saves a huge amount of time that would normally be spent travelling to work. There is no need to spend an hour each morning and evening stuck in traffic jams. You can spend that time working instead. - You save the cost of petrol that you would normally need to travel to work and also the cost of car parking tickets. For the company - They can employ people who don't live near to the office. This means they can choose people who might be willing to work for lower wages. They can even employ people from other countries. - If there is a shortage of skilled labour in the local area then they can get the skilled staff that they need from elsewhere in the country - they might be able to keep hold of valuable members of staff who might otherwise leave, for example, women who have just had a baby. - they can have smaller premises so they save money on rent, car parking space, heat etc. - they get workers who might be more satisified with their jobs and thus be more committed or work harder.

New job opportunities On the positive side, ICT has resulted in many new jobs being created created. Here are a few examples - I'm sure you can think of many more. Network Technician     

Helps set up office and school networks Monitors network performance Installs new software Sets up and monitors user accounts Ensures network security

Computer programmer  

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Writes the code for new software Adapts or develops existing software


Website Designers With the explosion of the Internet, there has been a huge demand for people who can design and write websites. There has also been many jobs created around web advertising, web hosting and e-commerce Help Desk Operator    

Answers technical problems from staff Provides advice when software/hardware not working Resets passwords Can remotely control a computer screen to demonstrate how to do something.

Business Analyst Because businesses need specialist software and hardware to suit their particular needs, most large organisations employ a team of business analysts. These analysts examine the methods currently used by the company and determine what works and what needs improving. They then work with employees, employers and software developers to design and create a new system to solve the business' requirements. ICT Teacher?

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3.3 online services and working patterns Keywords: part-time working, job sharing, flexible working, working from home, compressed hours.

3.5 online services and security and privacy of data. Keywords: encryption, decrypt, public-key, hackers, TANs, pins, chip & pin, SSl, TLS, protocols, data protection legislation, duty of confidence, duty of fidelity, anonymised information, aggregated information, skimming, pharming, phishing. Privacy and Security Files used in applications are vital to the running of a system. Any loss or corruption of data will have serious or fatal implications for the performance of the application. Delays, loss of business and possible legal action may result. For these reasons many safeguards are used to protect files from: Hardware failures Software failures Human Errors Deliberate damage. There are numerous methods of file security : Physical security File backup Transaction Log Archiving Passwords Encryption Physical Security Security guards Alarm systems Locks on rooms and on computers Access to rooms by swipe cards / fingerprint scan / retina scan

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Write-protect mechanisms File Backup. One straightforward method is to make a backup copy of all your important files. Generations of Files. If an application, such as a payroll, uses sequential files then a suitable method of file security is the Grandfather, Father, Son method. Every time a master file is updated, the original file is copied together with any changes ( held on the transaction file) to a new master file. This new master file is cal!ed the 'Son' and the previous master file the 'Father'. The next time the files are updated a new son is produced, the old 'Son' becomes the 'Father', and the old 'Father' becomes the 'Grandfather'. There now exists three generations of the master file. If the new master file becomes corrupted, lost or damaged it can be re-created from its father together with the relevant transaction file, which has to be kept. This process usually only proceeds for 3 or 4 generations at which point the tapes are reused. However, large DP organisations such as the DVLC keep up to 19 generations of files. Transaction Logs An on-line system, such as a theatre seat booking or reservation system, or a cash-card system, can not use this method as the records are not processed sequentially but randomly. This sort of system can use a transaction log to keep a record of all the transactions that have taken place in a day. Then if the master file becomes corrupted the previous days master file can be updated using this transaction log. Of course, a backup copy of the master file should be made at the end of every day. Some applications may perform a backup of the master file and transaction file periodically during the day. Archive Files In some applications, such as a Banking system for current accounts, data such as the details of the customers account from the previous year will not be held on-line but copied from disc storage, or a mass storage device, onto magnetic tape and held in a fire-proof, waterproof, bomb-proof! bunker away from the Bank's computer centre. The process of copying and storing files on a secure medium in a safe place 54


is called archiving. Passwords - Levels of permitted access On multi-access computer systems many different types of user are logged into a vast filing system. In order to gain access to the system a user is supplied with a user name or ID together with a personal password. Some files may be open for reading by anyone, others only by those users in the same department, and others only for reading by individuals, such as 'mail'. The main computer's operating system makes sure that file access is appropriate for the user's password. Encryption To maintain file security when data is transferred from one computer to another using a communications link the data can be encrypted. This means that the data is encodedin some way before it is sent, and therefore meaningless to anyone intercepting the message. The data is then decoded at the receiving end by the user who knows the way to decrypt it (often referred to as the key). Data encryption can also be used when data is stored on a file.

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Preventing Data Misuse More and more businesses and organisations are storing our personal data so that it can be used to contact us later, for purposes like marketing (selling us things). Every time you fill in a form on a website, or sign up for a special offer, your details are stored in a database somewhere. If the data in a database falls into the wrong hands, this can lead to some very big problems... Data Misuse If the wrong person has access to your data, they can misuse it in a variety of ways: 

Data could be deleted (e.g. your bank balance could be wiped out) 

Data could be changed (e.g. you could end up with a criminal record, for something you didn't do) 

Data could be used for blackmail (e.g. your school record might contain information that you are embarrassed about, and someone might threaten to reveal it to the press!) 

Data could be used to help someone impersonate you (e.g. they could apply for a bank loan in your name). This is known as Identity Theft

Identity theft is becoming a huge problem. It's an easy way for a criminal to get money, or goods there is little risk to them since they are pretending to be someone else! Imagine if you received a letter from the bank asking for repayment of a $20,000 loan that you didn't apply for! How could you prove you didn't apply for it when the person who applied had all of your personal information (your name, date of birth, ID numbers, address, parent's names, etc.)? The more data you reveal about yourself, the more likely you are to be a victim of identity theft. Time to change your privacy settings on FaceBook! Time to put good passwords on your mobile phone and your laptop! How Do Bad People Get Your Data? So how does data end up in the wrong people's hands?

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A CD-ROM or memory stick might be left somewhere by mistake (e.g. on a train)

A hacker might break in to a network

A password might be guessed


Information might be sent in an e-mail which is intercepted

Someone might read things on an unattended monitor

The data might be sold by someone for profit

Discarded printouts can be found in bins

How Do You Stop Data Getting into the Wrong Hands? You should always follow sensible precautions when dealing with other people's data:

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Encrypt files, especially when taken out of the office (e.g. on a memory stick, or sent via email)

Use strong passwords

Lock your computer when you are away from it

Always shred printouts that contain sensitive data


Data Protection Act Many governments have realised the need to protect peoples' data from misuse, and have created Data Protection Acts. These are a legal rules that must be followed by any business of organisation that keeps a database containing peoples' personal data.

What is the Data Protection Act? What are the Eight Principles of DPA?

Who is the Information Commissioner? Who is the Data controller? Who is the Data subject? What is personal data? What is sensitive data? Who is exempt from DPA?

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The Data Protection Act (DPA) is a law designed to protect personal data stored on computers or in an organised paper filing system. 1. Data must be kept secure; 2. Data stored must be relevant; 3. Data stored must be kept no longer than necessary; 4. Data stored must be kept accurate and up-todate. 5. Data must be obtained and processed lawfully; 6. Data must be processed within the data subject rights; 7. Data must be obtained and specified for lawful purposes; 8. Data must not be transferred to countries without adequate data protection laws. Person who has the power to enforce the Act.

Person or Company that collects and keeps data about people. Person who has data about them stored outside their direct control. ....... Is about living people and could be. E.g. Name, address ...... Is also about living people, but it includes one or more details of a data subject's. E.g. Religion, criminal activity. • Any data held for National Security reasons e.g. MI5 • Police can access personal information in order to solve crimes. • The taxman can access personal information to ensure people pay their tax! • Any data held for domestic purposes at home e.g. birthday lists, address books.


3.6 Online services and health and safety Keywords: RSI, vision and posture problems, electrocution, fire, tripping, heavy equipment.

Vision/Posture

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60


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Section 4: System Life Cycle Feasibility study Once the system analyst is convinced that the problem could be solved with a new IT system they have to determine whether it is feasible to actually go ahead and develop the system. This is the purpose of a 'feasibility study'. Some of the questions that will need to be answered in a feasibility study are: Cost

Budget

Time

Skills

How much would the new system cost to develop? Would there be enough money available in the budget to develop the system? How long would it take to make the system from start to finish? Does the company have the skills in-house or would it need to go to a specialist software development firm?

Hardware to

Does the company have the necessary hardware to develop the

develop

system?

Hardware to run

Software

Training

Would new hardware be needed to run the system and if so how much would that cost? Does the company have the necessary software to develop the system? What would the training implications be once the system had been developed?

Technical

After finding out what is required is it technically possible to create the

feasibility

system

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4.1

Analysis

Keywords: collect information, establish inputs, outputs, processes, record information, identify problems. n order to reach this stage in the SLC, management would have listened to the alternative solutions presented by the system analyst and have decided to either commission a brand new IT system or have changes made to their current system. During the earlier 'definition' phase the analysis looked superficially at the current system and the potential benefits of a new system. During this 'investigation and analysis' phase they will carry out very detailed investigations in order to fully understand the current system and the proposed new system. The current system     

how staff / customers interact with the current system i.e. how tasks are carried out how other systems interact with the current system what is good about the current system what causes problems with the current system which parts of the system are critical to the business

The proposed new system    

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what the new system is expected to be able to do how the new system is expected to do this what people want from the new system which working methods from the old system should be incorporated into the new system


Investigation methods In order to find the answers to the points on made on the previous page the system analyst will do some or all of the following:

The analyst will interview selected staff who use the current system in order to Face-to-face Interviews

get a detailed overview of how things work. They will want to know what the main problems are and whether users have any suggestions on how to improve the way things work.

The analyst will observe users actually using the system. They will probably Observation

follow a complete process from start to finish and note down every interaction that happens

Questionnaires enable the analyst to obtain the views of a large number of staff/ users. Questionnaires are also easier to analyse than face-to-face Questionnaires

Examination of business documents

Paper trail

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interviews but the trade-off is that they don't give as much detail.

Most organisations have business documents and written processes/ procedures relating to the current IT system. These documents detail how the system works and the processes which users should follow. The analyst will examine these documents in detail.

Following information from the point it enters the system and observing what outputs are created at each point in the system.


documentation All of the information obtained through interviews, questionnaires, observations and paper trails is carefully examined and analysed to determine the requirements for the new IT system. The findings are translated into a set of specific diagrams which represent how the system will work and the processes required. The main diagrams are:

System

These show the relationships between the various systems in the company (or even

diagrams

outside if relevant) - how they interact, what depends on what and so on.

Most systems deal with information in one way or another. What really matters is Data Flow Diagrams

how the information flows through the system. How does it branch and re-join. What outputs are created and so on. The 'data flow' diagram seeks to show this movement through the system.

People handle information in a specific way - they have a 'process'. For example, an employee makes an expense claim. First of all their manager counter-signs the Process diagrams

claim. It then goes to the account manager who authorises payment and so on...This is 'process flow' in action. Process diagrams try to show how people interact with the system - who and when (and why).

Once the diagrams have been completed, two key documents/ reports are produced:

1. A full written analysis of the current system, the processes and the problem it causes

2. Detailed user requirements for the new system

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These documents will be used by the system developers and so must be clearly written, broken down into relevant stages and contain all of the necessary details for them to create the new system.

User requirements document The 'User Requirements Document' does not define the hardware or software design but rather seeks to capture the essence of what needs to be done. Some fairly standard headings within the document are: An introduction .... "The project has been developed in order to create a new invoicing system to replace the AIX400 computer system..." The introduction gives a broad description of the project and its aspirations. Context .... "The project was developed in light of the up-coming new regulations and also the increasing awareness that the existing system could no longer meet customer expectations ...." This section provides the background to the project. Specific details required Having provided a broad description and some context to the project this section deals with specific things that need to be included in the system. Examples:   

The system will be able to use a query to create a mail merged personalised letter. The system must create an invoice in less than 3 seconds The system will be able to print a management report onto A4 paper, portrait layout.

Notice that these specific requirements are all measurable. The document should NOT contain vague statements such as "The computer will run as fast as possible..." because you cannot know if 'as fast as possible' has been met when the system finally gets switched on. The Requirements Specification is the 'contract' between project managers and the client. It will be used at the testing stage to confirm that the system performs as the client expects.

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4.2

Design

Keywords: programmer, data collection forms, screen layouts, boxes, colours, fonts, validation checks, input devices, user, format, data file structures, system flowchart, data flow diagram, master file, transaction file, off-the-shelf, purpose-built. This is the next stage in the SLC and it follows on from the Investigation and Analysis stage. Now that the project manager and the client have agreed on the requirements (Requirements Specification) it is time to define how the project is going to be carried out. This is the Design phase of the project. It is about planning the project in detail so that that system will meet user requirements. The following are tasks that must take place during this phase:

Project planning is all about handling people: how many, where and when are they needed. In addition those people will need resources to carry out their jobs: computers, offices etc. There are a number of different project planning tools which will be used during this stage in order to effectively plan out the project, timescale and the resources required. These include: Project planning 

Gantt Charts

Critical Path Analysis (CPA)

Project Management Software

This document will include the following information: Data capture methods for the system Data inputs to the system Data outputs from the system System requirements

Data processing within the system

specification The file structure for date storage The user interface i.e. screen layouts, buttons, error messages How information is accessed and indexed or sorted. The operating system to be used

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The hardware to be used to run the new system

A Data dictionary defines the:

Data Dictionary

tables, fields, records and relationships

constants, variables and data structures

validation that is required in the system

query structures

Once the user requirements document and the system requirements specification have been written the analyst will know exactly what the system Testing

should be able to do.

documentation A test plan is written at this stage to test the key parts of the system once it has been developed.

A 'prototype' is something that represents what you will finally create without having to worry about all the details - it captures the essential details to confirm that the design is likely to work. Prototyping

In software the prototype is often written in a kind of shorthand English called pseudo-code, for instance 'Read in the record'. The details do not matter at this stage but a record must be 'read in'.

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4.3

Development & Testing

Keywords: test data, live data, normal, abnormal, extreme, test plan, improvements. Once the design stage has been completed the software developers can begin to write the code and actually develop the new system. The system could either be completely bespoke with every line of code being written by specialist programmers or it could be developed from an 'off-the-shelf' application which is then customised. The developers will follow the system requirement specification exactly, if it states to put a button 500 px by 100 px, colour #ffefdf in the top left hand corner that is exactly what they will do. They should not deviate from the specification in any way without consulting the analyst. During this stage some of the following are developed:        

the tables and data structures validation routines data capture forms data input forms automated processing routines i.e. macros queries the user interface i.e. screen, buttons, help messages printing outputs

 

Once the system has been developed it must be tested to ensure that it is working as expected. Testing Team A team of testers will have been chosen to test the system. They are known as beta testers. Their role is to check that the system does everything exactly as specified in the system and user specification. Although this team will check if the system is user friendly that is not their main role. A separate team is usually appointed made up of front end users to 'user test' the system once it has been passed by the beta testers.

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 

Test Plan In an ideal world a test plan will have been written during the design stage. However, sometimes the test plan gets left until now. The test plan is a detailed document which a team of testers must follow carefully. It will set out every single test they are to do on the system, what data they should enter and what result they should expect to obtain. For example one test might look something like this:

Test Part of no. system

Expected Actual Pass What is Test data result result / Fail being tested

Input mask on postcode to check Fail that should not Customer numbers 45CV523 be able to input form cannot be enter entered postcode where letters should be.

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   

  

The first five columns are already completed in the test plan. The final two columns are left blank for the testers to complete when they do the test on the system. The testers follow the plan exactly. They enter the data just as it is shown in the plan and then they record what happened and whether the test passed or failed. If the test was passed they go onto the next test. If it failed they fill in a form to tell the developers that they need to look at that part of the system again. The testers normally take screen shots of every test to provide evidence of what they have done. These can be referred to by the developers if they cannot replicate the problem. They can also be used by an audit team at the end of the project to check that the testing was done properly. This stage may seem to you a bit pedantic - after all why couldn't the developer have run this test when they were coding the software and then fix it instantly? - Answer: Human Nature! It is a very bad idea to have the person who codes the software to test it! This is because they know too much and so will tend to make assumptions about how real users will use their software. The best testers are those who know nothing about the system and will do things to the system the developer never imagined! Just like real users!

Test Selection

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It is important to realise that with the best will in the world it is not possible to test every part of the system.

Consider a system having 8 data inputs that can applied in any combination. The maths says that there are over 16 million possible combinations of just 8 inputs!

So the skill of the testing team is to carefully select apractical number of tests that can be carried out in the time available and yet be confident that the system is working.


This is why complicated software often has bugs even after being released. It is simply not practical to test everything.

Test Data 

It is important that any testing which checks the validation routines should include:

Data that is within the normal range and will be accepted

Data that is on the extreme limits of the range but should be accepted e.g. if the validation says that price <=£100 then £100 should be tested as that is right at the outer limit.

Data that should fail (erroneous data) should be tested. For the test mentioned previously, the test might be: enter £100.01

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Iteration or Looping Around. If an issue is found it may actually be a problem with the user requirement itself. It is quite common for the user requirement to not consider an unexpected situation.

For instance, the document might state that the system is to be used by 10 people at the same time. But by the time testing is underway something changes in the company and now the system needs to deal with 20 people instead.

In which case the client has to agree to change the user requirement document.

Then testing continues with the modified user requirement document.

Changing user requirements part way through a project causes delays and extra cost. It is often the most common reason a project fails especially on large projects.

Testing is usually an 'iterative' process.


4.4

Implementation

Keywords: parallel running, direct changeover, phased, pilot. The system has been developed and tested. It is working correctly and doing everything that was agreed during the design stage. The business is waiting in eager anticipation for the new system to be handed over to them. A key decision is which method of the four different methods of installation will be chosen. These are:

1. 2. 3. 4.

Direct Parallel Phased Pilot

Direct method This is where the company literally switches off the old system and switches on the new one. This is probably the most straightforward method but is also probably the riskiest.

Advantages New system available to everyone in company immediately

Disadvantages

Most risky method - if something goes wrong, there is nothing to fall back on. Have to wait while the problem is fixed.

Often the cheapest method of

Have to transfer all of the data to the new one before the old

installation

one can be switched off

Don't need to keep duplicate sets of data

There will be a period of time where no system is available because can't have old one working while new one is being switched on There will be a period of upheaval while the system is brand new and staff are finding their way around it

Parallel method This is a more popular method than the previous one. With a parallel changeover the organisation runs both the old and new system in parallel for a time. Once the organisation is sure that the new system is working properly and that staff are ready to begin using it they will make the decision to completely change over. During a quiet period, perhaps during the night or at a weekend, the data is fully transferred from the old system which is then shut down. 73


Advantages

Disadvantages

Less risky than the direct method. If the new system

Time consuming as data has to be

fails, the old system is still up-to-date

entered onto both systems

Less stress for staff as they still have the security of

One system can become out of synch.

the old system

with the other.

Staff can take their time to learn to use the new

Maintaining duplicate sets of data can

system

lead to errors Extra cost of running and maintaining two systems

Phased method This is where the old system is still active but parts of the new system or modules are brought online, for example, perhaps just the data entry screens and the printing modules are made available but the 'back end' of the system remains the same. Once any problems are ironed out with the new modules then extra modules will be introduced. Effectively the installation happens in small chunks.

Advantages Less risk of the whole system going wrong, if something happens, it will only affect that specific part.

Staff are introduced to the changes in small stages

Disadvantages

This method of installation can take a long period of time

As parts of the system are used, users ask for changes which then hold up the installation of the next phase It might be difficult to integrate the old and the new systems

Pilot method

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This is where the complete new system is installed and tested in a small number of departments or branches. They then use the system and report their feedback and any issues to the analyst. Once the organisation is confident that the system is working as expected, it will be rolled out across the whole organisation.

Advantages

Only a small part of the business is affected. The rest of the business continues using the old system for now

Any problems or issues are identified without it affecting the whole company

When the rollout happens, staff from the pilot departments can be involved in training other staff

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Disadvantages Even though it is only introduced to a small number of departments, those chosen will have the same disadvantages experienced as for a 'direct changeover' Those staff using the new system might not be able to easily share data with the rest of the company who are still on the old system

Extra work for IT staff who are having to support two different systems


4.5

Documentation

Keywords: technical, user, systems, program, User Documentation The development of the user documentation is left until after the testingphase is complete. If it is created beforehand, parts of the system could change as a result of faults being discovered. User documentation is provided to the user which gives an overview of how to use the system. Paper based user documents are usually in the form of a booklet or file. The typical format of a paper-based user document includes       

Table of contents Short introduction or overview of the system Brief technical details such as the hardware and software requirements to run the system User Guide : this is the bulk of the document Glossary of technical terms Troubleshooting: usually a simple list of things to check before calling for further help Index

User documentation is often used during staff training sessions in order to familiarise the staff with both the system and the user documents.

On-Screen Documentation As well as paper-based user documentation, many systems now also have on-screen documentation. On-screen documentation can take the form of:      

A help menu Web pages Popup help boxes PDF documents FAQ section Video tutorials

Many help systems have a search facility to answer those 'How do I ....' type of questions the user may have. Another popular format is the 'FAQ' or Frequently Asked Questions document. Typical features of the help system include:        

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Text search facility Hyperlinks and navigation buttons to move around the help documentation Buttons with relevant text Worked examples of how to use a feature Links to related features Multimedia help in the form of video tutorials or spoken word 'Tool tips' which appear when you hover over a word or sentence Pop-up instructions when you press a certain function key


The online version has the advantage that it can be easily updated with the latest information compared to a published paper based system.

Technical Documentation This is intended for technical maintenance of the system. Engineers and software developers will refer to the technical documentation in order tomake changes to the system after it has been installed. Technical documentation is created from the very first stages of the development phase as the original project team set down the details as they build the system. Typical content of technical documentation includes       

Source code with copious commentary explaining how that part of the code works Data structures used within the system File formats used File naming convention Validation ranges for data input Macro scripts, including comments to explain each stage of the macro Internal details of a database such as tables, relationships, records, queries used Navigation layout such as a site map or link map of the system

Other technical details to help with maintenance include    

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Test logs and test results Security details of the system How to install the system How to backup and restore the system


4.6

Evaluation

Keywords: criteria, feedback, limitations, improvements, observe, measure, questionnaires, interviews, The installation stage is over: The system is up and running. Staff are fully trained and bugs have been ironed out. This next stage is called the 'Evaluation phase'. The evaluation stage looks at the overall project and considers how things went. Evaluation involves all the key players in the project. These include        

Original client Project manager System Analyst Designers Developers Testers Support staff such as trainers A selection of end-users

Each person role has a part to play in the evaluation. During the evaluation stage, two key questions are considered:

1. Does the finished solution meet its requirements? 2. Does it solve the problem? The key document that drives the evaluation is the User Requirements Document. Perhaps not every detail will be covered, but certainly failures and particular successes should be discussed. Further to those two questions, the evaluation considers  

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Lessons learnt from the problems encountered so the next project will be even smoother and successful Any maintenance and support needed in the day-to-day running of the system


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