ict systems all

8/2/2019 Ict Systems All

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ICT SystemsWeather ForecastingSome of the world's most powerful computers are used to forecast the weather. Accuracy of forecasts is

improving all the time and many people rely on these forecasts - TV companies, shipping, farmers, the

military etc...

The computer systems are also used for hurricane and tornado tracking, global warming monitoring, oceanmonitoring (eg El Nino).

Data collection.Millions of pieces of data (observations such as temperature, pressure,

humidity, infra-red radiation) are collected from

satellites weather stations

weather balloons aircraft radar weather ships automatic weather buoys

All these readings are sent to the Met. Office computer systems at Bracknell.

Thermometers - measure temperature

Barometers - measure air pressure

Anemometers - measure wind speed

HardwareThe Meteorological Office computer is a Cray T3E supercomputer. It uses parallel processing and has over

700 processors.It is capable of very fast processing.

ProcessingThe data is stored in a large database. The first task is to perform a quality control check on the data

(validation) and to reject all invalid readings.The data is formatted to fit in with a numerical 'Unified Model' of readings. From this computer model,forecasts can be made.

The bulk of processing is 'number-crunching' and solving thousands of inter-

related equations. The computer can also produce global and local charts of

weather information.

SoftwareAt the Met. Office in Bracknell, the complex software which processes the readings has been written in

Fortran and a user-friendly GUI has been added.


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TeleworkingICT allows some workers to work from home. This is called teleworking.

An Internet link to the office allows them to upload or download work as required and email can be used to

send messages to other workers or to customers.

Advantages : no need to commute to work so saves time and travel expenses. the business does not have to provide office space or other facilities (canteen, toilets etc) office bills are cut (eg electricity) flexible hours - the employee can work any hours.Disadvantages : the cost of computers and Internet provision loss of social contact there may be distractions in the home motivation may be harder it may be difficult for management to check if the work is being done

SimulationSome computer systems simulate real-life situations by using an approximate (mathematical) model. This

consists of a set of rules governing the behaviour of the system.

Behaviour of the system under differing conditions can then be studied and predictions made.

Advantages of using a computer model... there is no danger to humans extreme situations which may not occur very often may be studied they can be done in a controlled environment (eg computer room) it may be used repeatedly as often as needed.

Disadvantages of using a computer model... reality is complex and only an approximation of reality can be achieved. expensive hardware may be needed (eg flight simulator)Examples of Modelling Systems....Flight simulators Used for training pilots to fly. Difficult and dangerous flying conditions can besimulated (turbulence, storms, fog, lightning etc).

Pilots can practice real-time flying and landing at different airports throughout the world.

The simulator is built on hydraulic legs which move it around to increase the realism.


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Games - Some computer games simulate realistic situations. Constructing towns, train driving,military exercises etc.Science Experiments - Chemical experiments may be simulated without actually performing themand production of gases may be studied using different concentrations of chemicals etc...

Biological studies of populations under different situations can be studied.

Other examples include... Electronic circuit board simulators Kitchen design programs Architectural building - strengths and stresses Economic and financial modelling Traffic flow simulations Acoustic simulators for design of concert halls. Medical simulations ...and many many others...

School Registration SystemsRegistration keeps a check on a pupil's attendance. This can be done electronically using computers linked

on a network.

Each classroom has a computer running a registration program. Each pupil is marked as either 'Present'

or 'Absent'. This can be done at the start of every lesson in the day.

A central computer collects and analyses all the data.

Advantages: more frequent check on pupils' attendance eg. every lesson automatic monitoring of absence automatic calculation of attendance figures absence patterns can be noticed eg. if a pupil is absent every Friday. better attendance by pupils (they know their absence will be noticed!)Disadvantages:

computers needed in every classroom teachers may need to be trained to use it (ICT skills needed)

Robotics and BionicsA robot is a computer-controlled mechanical device, that can be programmed to perform a sequence of

actions.

A robot can be programmed by ...

entering a new set or program instructions.


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manually guiding it through a sequence of actions, which it can then repeat.There are many factories where robots are used on a production line. The jobs that the robots do are

generally jobs which humans would find boring and repetitive, or jobs that may be dangerous.

These jobs would previously have been done by humans, but they may have been re-trained for other jobs -

or possibly have been made redundant.

There will be some initial costs in purchasing the equipment and installing it, but the advantages of arobotic system would include.. robots work 24 hours a day - no need for breaks. robots do not need to be paid. robots work consistently - they do not get tired or make mistakes.

BUT ... robots cannot think for themselves and may not respond well to new situations. robots can be very expensive.

Example :Computer-controlled robots may be found in car-making factories. The jobs..

welding or assembling parts paint spraying moving heavy parts around the factory.

The robots will have been programmed to perform the jobs they do.

Bionics is the study of robots that have biological functions.Artificial limbs such as arms are being developed that can be controlled by a person's thoughts.

SupermarketLANs and WANs may be linked together. For example, a supermarket may have a LAN linking all its computers

and terminals... ...and each branch of a supermarket may be connected to a WAN covering the whole country.

All goods in a supermarket have barcodes printed on them.

When a customer pays for the goods, each item's barcode is passed over a

barcode reader built into the PoS (Point-of-Sale) terminal. This reads the bar

code and sends it to the main computer.

The computer stores a database containing information about all the

products the supermarket sells. The computer sends the price and the

description of the item back to the POS terminal.

The price is added to the customer's bill.


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The price and the description are displayed on a small monitor. They also get printed onto the customer's

receipt.

The computer will also note that one of this item has been sold and will reduce the stock level on file. The

computer always knows exactly how many of each item is in the supermarket. This is called automatic

stock control.

At the end of each day, the computer sends out requests over the WAN for more of those items which are

running low.

The customer can pay the bill using EFT (Electronic Funds Transfer). Acredit card (or debit card) is swiped through a card reader to read the

customer's bank account details. These details and the amount of the bill are

sent through the network to the bank's computer system.

The correct amount of money is transferred by the computer system from the

customer's account to the supermarket's account.

PayrollAt the end of each pay period, a business needs to pay its employees.

A payroll system uses a computer to calculate the wages of each employee, print out pay-slips and record

the information for accounting purposes.

Input : This may come from ... a database of employees details (salaries, pay rates, bonus rates etc) if employees are paid by the hour then timesheets would be used to input and validate the number

of hours worked and number of hours overtime. (possibly using OMR or OCR techniques)

Process : The computer needs to calculate .. the gross amount earned by each employee. any bonuses any deductions such as tax, national insurance etc the net amount earned by each employee.

Output : The computer would need to .. print pay-slips with amounts and deductions (using pre-printed stationery) update the employee database. output details of payments to BACS (Bankers Automated Clearing Service) to pay money directly

into employees' bank accounts.

print summary reports.


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A Payroll system is usually run as a batch processing system. Data may be entered for a number of

departments or branches of a company and then the processing is done when all the data has been

collected.

As there is no urgency for the output, the payroll processing may be run at off-peak times (eg overnight).

The database of the employees and the time sheets will need to be kept secure from unauthorised access.

(Employees must not be able to alter their data!)

The employee database is updated in the payroll process. A backup copy of the database is made before

this is done.

The new database is called the 'son' and the backup is the 'father'. Previous generations of backups are

referred to as 'grandfather' etc...

Shopping OnlineShopping over the Internet is increasingly popular.

Retailers create websites which display the items they are selling.

Customers access the web-site using the Internet, and add the items they wish to buy to a 'shopping-

basket', and then pay by credit or debit card. (Credit card details are encrypted on secure sites)

The goods are delivered to the buyer's house.Online shopping is often called e-

commerce.Advantages of e-commerce:To the customer...

greater range of goods can be done from home goods are delivered to the door-step

To the business.. the business does not have to provide and pay for premises businesses can attract customers from all over the world

Disadvantages : there is a couple of days delay before receiving goods. possibility of credit card information getting into the wrong hands you cannot see or touch the goods before buying

Modern Postal HandlingThe postal system is a global network used to deliver mail. Each country has its own postal service and

have to collaborate to make sure every mail item reaches its destination.


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After mail is collected, it has to be sorted. Parcels are separated from letters, and then letters arefed into sorting machines, where they are turned so that the stamp is always in the same position.

Sorting machines use OCR (Optical Character Recognition) to read the postcodes. Letters getcancelled on the stamp so they cannot be used a second time. Letters are sorted by class, and by

destination.

First class long distance letters may travel by air to another sorting station, while second class mailtravels by rail or road.

Modern machines read the postcode and print the letter with a barcode, which is then used to sortthe mail into 'walk' order for the postman delivering them.

Some letters are rejected by the sorting machine (Eg. there may be no postcode), and these wouldthen be sorted by hand.

Mobile PhonesPortable telephones that can be used for voice calls, but may also have a number of other facilities...

text messages email access to the Internet games camera / video recorder photos or videos can be sent to other users mp3 player radio GPS

Mobile phones are powered by rechargeable batteries.

A SIM card stores configuration details about the phone (such as the phone number), and can betransferred from one phone to another.Some use a touchscreen interface. SIM stands for Subscriber

Identitiy Module.

Interactive TVTelevisions that receive digital signals may allow interactive viewing.

Viewers may be able to interact with the TV - they may be able to join in the games or quiz shows, access

the Internet or purchase items. Email will be available.

Viewers will not need to buy a computer and existing TVs can be adapted to

receive digital signals.

Digital TV should mean much better picture quality.

On some digital channels, viewers can select which camera they want to

use when viewing sports events. Some events or films are pay-to-view. You

will need to pay a fee to view them.


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GamingA popular use of computers in the home is for playing games.

On-line gaming involves playing games with others using a network link - usually the

Internet.

Games consoles (eg Nintendo Wii, Playstation, Xbox) are modified computers that canbe used with a display device to play games. Some applications are more serious - like improving physical

fitness.

There may be problems of addiction with computer games. It is easy to get too involved with playing games

and forget to do other important tasks - such as homework!

Some games are educational and may improve skills and hand-eye coordination ...

BUT ...

too much games playing may lead to loss of social skills and may have an effect on fitness and health.

E-CommerceShopping over the Internet is increasingly popular.

Retailers create websites which display the items they are selling.

Customers view the web-site and add the items they wish to buy to a 'shopping-basket', and then pay by

credit or debit card. (Card details are encrypted on secure sites)The goods are delivered to the buyer's

house.

Advantages of e-commerce: greater range of goods can be done from home goods are delivered to the door-step the business does not have to provide and pay for

premises

accessible globally

Disadvantages : there is a couple of days delay before receiving goods. possibility of credit card information getting into the

wrong hands

you cannot see or touch the goods before buying


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Online LearningA large amount of learning can be done using computers. The Internet is a vast source of information, but

you have to make sure the information is up-to-date and reliable.

Distance learning means learning where the teacher and the student are not in the same place ... using

the Internet, email, videoconferencing etc

Some learning courses are free but some you need to pay for.

Tutorials can be run that teach you anything from foreign languages to computer programming. They will

usually involve some explanation and some self-assessment so you know how well you are learning. The

tutorials may include some multimedia presentations.

One day, you may be sitting examinations online.

Advantages of online learning: you can go at your own pace you can do it at a time to suit you you can see how well you are learning from the self-assessments it can be done from home (or anywhere)Disadvantages of online learning: you may not be able to get help if you do not understand something it may be expensive

A VLE (Virtual Learning Environment) is a computer-based education system in which students andteachers interact. Tutorials and assessments will be done through web pages.

Digital PhotographyA digital camera is used for input. Photos are taken, stored and can then be loaded into a computer for

processing.

An image captured by a digital camera is made from a large number of pixels - coloured dots. The more

pixels - the better quality image.

When you buy a digital camera, look out for the resolution - the number of pixels in an image. Higher

resolution means better image detail. Resolution is usually measured in Megapixels.

1 Megapixel is approximately a million pixels. Most digital cameras are also capable of

recording sound and moving video.

Example : a 12-Megapixel camera will have about 12 million pixels in a photo.

Images can be stored on flash memory cards, which can then be transferred to a computer

that has a card reader.


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Images can be opened with photo editing software.You can then edit the image - such as change the

brightness, sharpen blurred images, or even remove 'red eye'.

ICT for Disabled PeopleThere are some special devices that enable disabled people to use computers...

Braille keyboard - a special keyboard with Braille symbols on each key. (patterns of raised bumps)Touch-sensitive screen - an input device where the user touches the screen, either with a finger or apointing device.Touchscreen devices are also widely used in public places where other input devices such as a mouse mightget stolen or damaged.

Eg. in museums, supermarkets.

Voice recognition systems use a microphone as an input device, where the user speaks instructions to the

computer.

There can be problems with voice recognition software if... the speaker has medical problems such as a cold and cannot speak clearly the speaker has a regional accent words are used that may have several possible meanings (two, to, too)

Text-to-Voice software can 'read' a document using a speaker as an output device.For partially sighted people, the desktop environment can be customised...Eg. Large

font size, contrasting colours etc

Sensors and Data LoggingMany measuring devices (sensors) can be linked to computers.

Examples : Sensors can measure - temperature eg to control a heating system light eg to control automatic street lighting sound eg to measure noise pollution infra red eg photo cells may be used to detect a break in a beam in a burglar alarm system. proximity eg to make sure robots do not crash into walls pressure eg to make sure robotic 'hands' do not grip an object too tightly. humidity eg to control an environment in a tropical greenhouse.

Data-logging - a method of automatic data capture where a reading from a sensor is input at regularintervals. This data can then be processed to provide analysis of the environment.

The time interval between data readings needs to be set....as well as the total length of time for which

readings are taken.You may be asked to use data logging in science experiments. Results can later be

analysed.


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Control SystemsSometimes computers (or microprocessors) are programmed to control mechanical devices (such as a

machine that sprays paint onto cars being manufactured).

Example: A traffic light system.

The output from a computer may be in the form of a signal to a hardware device.

In a control system, sensors are used to measure a physical quantity and send input to the controlling

computer.

The computer responds by sending an output signal to a control interface which activates various devices

eg a switch or an alarm.The output signal may be sent a to an actuator which activates a mechanical

device such as a motor. Control systems are frequently used in manufacturing industries.

Commonly used sensors are - heat sensors, light sensors, sound sensors, humidity sensors, movement

sensors.The control interface is needed because of the different operating characteristics of the computerand the devices.

Example:A computer may be used to control a greenhouse. Sensors continually send information about the

temperature and humidity in the greenhouse to the computer.

The computer will then analyse the data and send output signals, if necessary, to activate the heaters,

ventilators or sprinkler systems.

Control Processes with FeedbackSometimes in Industry a whole manufacturing process is controlled automatically by a computer system.

Input : Sensors take readings at regular time intervals and send the readings to the computer.Sensors may be measuring temperature, pressure, liquid flow rate etc

Process : The computer analyses the readings and decides whether action is needed to be taken.

Output : The computer sends output signals to devices which manage theprocess. An actuator is a device which reacts to a computer signal and willoperate a simple device (tap, motor, switch etc..)

Some systems use feedback...the result of an output signal affects the nextinput reading which affects the next output and so on... A closed loop means

there is no user interaction involved.

An example of a feedback system is a computer controlled heating system.

Repeat

Read temperature


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If too cool, turn heater on

otherwise turn heater off

Until switched offAn output signal may be in the form of a bit pattern...

Eg: 10010101 ..Each bit referring to a different device.

1 = 'Switch ON'0 = 'Switch OFF'

Most systems use feedback - the output affects the input.Eg If the computer is controlling a heater, any output from the computer will change the temperature

...which affects the input readings ...which affects the computer's next output...etc...

Data is processed as soon as the computer receives it. This allows the system to respond immediately to

any variations in the processing.Advantages : immediate response when needed. fewer staff are needed to run the process. the system can work all day - every day it keeps people away from dangerous processes.

Disadvantages : Unemployment may be greater as fewer staff are needed. the initial cost of the system may be expensive.

CAD/CAMCAD stands for Computer Aided Design.CAD is used for displaying and editing designs on the computer. Calculations can often be made (areas,

volumes, weights, stresses etc).

Input may be from a keyboard, graphics pad, light pen or touch-screen

monitors.

Example :CAD can be used for interior design work. Arranging furniture in a room.

This can be viewed from a number of different angles.

The arrangement can be changed on the computer and 'tested' without needing to

move actual furniture around.

CAD can be used to design... cars


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bridges buildings boats engines circuit boards ...and many more

Facilities include... creating and editing new designs viewing designs from different angles adding standard pre-designed shapes from a library calculations (areas, volumes, stresses etc) designs can be tested (eg electrical circuits)

Finished designs may be

...printed out using a graph plotter. ...used as input for a CAM process....

CAM stands for Computer Aided Manufacture.CAM uses a computer to control a manufacturing process. CNC (Computer Numerical Control) machines

such as

lathes milling machines drilling machines welding machines soldering machines robots.

...are used to produce the product.

In the CAD/CAM process slight changes to design are quickly and easily made and implemented. The

result of any change can be quickly analysed.

Online BookingIt is now possible to make bookings on-line for holidays, trains, planes, hotel rooms,theatre performances...and many others.

A travel agent for example, may have computers in all its branches directly connected

to a central computer where a database of all bookings is stored.

When a booking is made, the customer will need to provide input details (name, date,

place, number of people etc).

This form (on an Internet web page) is used for collecting details of a passenger's booking on the

Eurotunnel.


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These details are then used as input data when the booking is made.

This data is validated to check if the details are sensible. The computer will check to see if the booking is

available, and, if it is, the booking is made and it will then store the booking details in the database.

Documents will need to be output to give to the customer, confirming the booking and giving details about

it.

As soon as a customer makes a booking it has to be processed immediately, so that no other customer can

make the same booking.

It is essential that no data is lost, so the database will have to be regularly backed up.

If payments for the booking are required, then these can generally be done on-line using a Credit card or a

Debit card. If details of these are transmitted over the Internet, the website must be secure so that this

information cannot be stolen.

BankingA bank uses a large database of all its customers' details.

Every bank customer has a bank account with a unique account number. This is used as the key field for

the customer's database record. All the transactions a customer makes are stored in the database.

When a payment is made to someone else, it can be made ...

by taking out cash from an ATM and use it for payment by writing a cheque by using online banking to transfer money use a Debit Card

ATM stands for Automatic Teller Machine.

A user needs to insert a bank card and enter a PIN (Personal Identification Number) to verify that they

are the correct owner of the card.

An ATM allows a user to ... withdraw cash obtain a balance (how much money is in the account) print a small statement of recent transactions order a new cheque book change your PIN top up a mobile phoneAdvantages of ATMs ... Open 24/7 - all day every day


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Always nearby - supermarkets, petrol stations, banks. Fast service so no long queues The bank need not employ so many staff

... but they may run out of money at busy times, or a user may forget their PIN.

Bank cheques are used to pay money to somebody else. Cheques are handed in to a bank and are then

processed.

All cheques are sent to a clearing house where they are read using MICR (Magnetic Ink Character

Recognition), and the money is transferred from one account to another.

Bank cheques are being replaced by other methods.

When filling in a cheque you must enter five things -

the payee the date the amount in words the amount in figures your signatureHome Banking means using your computer and the Internet to manage your money.

A user has to be authorised by entering a password, and can then transfer money or make payments to

others.

Advantages of Home Banking ... a user can access their account 24/7 - all day every day no need to travel, it can be done from home you can use home banking anywhere in the world eg. on holiday

... but there must be rigorous security measures in place to stop criminals accessing other people's

accounts and stealing money.

A bank Debit Card can be used to make a payment in a

shop or online.

In a shop, the card is swiped with a Card Reader, and the

money is transferred from the user's account to the shop's

account using EFT (Electronic Funds Transfer).


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Artificial Intelligence and Expert SystemsArtificial Intelligence is the science of programming computers so they have the appearance of humanintelligence.An expert system...

...has a large database of knowledge. ...allows the database to be interrogated. ...has a set of rules (inference engine) for making deductions.

An expert system is a computer system which simulates the knowledge and expertise of a human expert.For example, in Medicine, expert systems are being used for disease diagnosis.

The patient's details and symptoms are input, and the system outputs probable diagnoses, recommended

treatments or drugs which may be prescribed.

Expert systems are not really replacing doctors but are being used to help

them. There are ethical and legal reasons for this - if a computerised

diagnosis is wrong, who do you sue?The advantages of an expert system over a doctor are...

...a large database of knowledge can be added to and kept up-to-date- it can store more knowledge than a person.

...the system cannot 'forget' or get facts wrong. ...it survives forever. There is no loss of knowledge as there is when a human expert retires. ...the computer can access specialist knowledge that a human expert may not have.

An expert system would be programmed using an AI (Artificial Intelligence) language such as PROLOG.