IGCSE ICT

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Autonomous Aeroplane

- February 03, 2022

Autonomous (pilotless) aeroplanes Aeroplanes have used auto-pilots for many years to control flights. Human pilots only take over during take-off and landing. Autonomous (pilotless) aeroplanes would make even more extensive use of sensors, actuators and microprocessors to control all stages of the flight. Some of the main features of a control system on a pilotless aeroplane would include: » sensors to detect turbulence to ensure smooth flights » an increase in self-testing of all circuits and systems » sensors that would automatically detect depressurisation in the cabin, therefore allowing for quick stabilisation of the aeroplane » use of GPS for navigation and speed calculations » use of actuators to control, for example, throttle, flaps (on the wings) and the rudder. Consider some of the advantages and disadvantages specific to pilotless aeroplanes:

Autonomous Train

- February 03, 2022

Autonomous Train Autonomous (driverless) trains have been around for a number of years in a number of large cities. As with other autonomous vehicles, driverless trains make considerable use of sensors, cameras, actuators and on-board computers/microprocessors. Autonomous trains make use of a system called LiDaR (Light Detection and Ranging); LiDaR uses lasers which build up a 3D image of the surroundings. Other sensors (such as proximity sensors on train doors) and cameras (including infrared cameras) are all used for various purposes to help control the train and maintain safety. The control system in the train also makes use of global positioning satellite technology, which allows accurate changes in speed and direction to be calculated. Again, actuators pay a huge role here in controlling the train’s speed, braking and the opening and closing of the train doors. The safety improvements made by these autonomous systems are fairly obvious. Consider some of the advantages and disadv

Autonomous cars, buses, vans

- February 03, 2022

Autonomous cars, buses, vans In this section, we will consider autonomous cars as our example. Autonomous cars use sensors, cameras, actuators and microprocessors (together with very complex algorithms) to carry out their actions safely. Sensors (radar and ultrasonics) and cameras allow the control systems in cars to perform critical functions by sensing the dynamic conditions on a road. They act as the ‘eyes’ and ‘ears’ of the car. Microprocessors process the data received from cameras and sensors and send signals to actuators to perform physical actions, such as: » change gear » apply the brakes » turn the steering wheel. Cameras catch visual data from the surroundings, while radar and ultrasonics allow the vehicle to build up a 3D image of its surroundings (very important when visibility is poor, such as in heavy rain, fog or at night). Suppose an autonomous car is approaching a set of traffic lights which areshowing red. The first thing the control system in the car needs to reco

Transport Control Systems

- February 03, 2022

Control of smart road systems and smart signs Many modern motorways are now called smart motorways. This is because the monitoring and control of the traffic and/or the information displayed on the motorway signs is controlled by a central computer system. If there has been an accident or there is considerable traffic congestion, then smart motorway signs can control the traffic to keep it moving or redirect it to avoid the accident. Even the traffic lights in cities are now computer controlled systems. However, imagine the chaos that would be caused if any of these systems were hacked. Somebody could then have control over a chosen section of the road network. That has huge safety and security implications. Rail and airline network control systems Safely coordinating the large number of trains and aeroplanes entering and leaving stations and airports is a complex task, but computerised monitoring systems make this possible. It is possible to run a more efficient timetable under total

Adware & Ransonware

- February 03, 2022

ADWARE Adware is a type of malware. At its least dangerous, it will attempt to flood an end-user with unwanted advertising. For example, it could redirect a user’s browser to a fake website that contains promotional advertising. They can be in the form of pop-ups, or appear in the browser’s toolbar thus redirecting the search request. Although not necessarily harmful, adware can: » highlight weaknesses in a user’s security defences » be hard to remove – they defeat most anti-malware software because it can be difficult to determine whether or not they are harmful » hijack a browser and create its own default search requests. RANSOMWARE Essentially, ransomware are programs that encrypt data on a user’s computer and ‘hold the data hostage’. The cybercriminal just waits until the ransom money is paid and, sometimes, the decryption key is then sent to the user. It has caused considerable damage to some companies and individuals. Imagine a situation where you log on to your computer, on

Spyware or Key logging Software

- February 03, 2022

KEY LOGGING SOFTWARE Key logging software (or key loggers) is a form of spyware. It gathers information by monitoring a user’s keyboard activities carried out on their computer. The software stores keystrokes in a small file which is automatically emailed to the cybercriminal responsible for the software. It is primarily designed to monitor and capture web browsing and other activities and capture personal data (for example, bank account numbers, passwords and credit/debit card details). Key loggers can be detected and removed by anti-spyware software. Banks try and overcome this risk, by only asking for a different part of the password each time you log on (for example, ‘please give the 3rd, 4th and 8th character in your password’). Sometimes drop-down boxes are also used because this involves on-screen selection using a mouse, which is difficult for the key logger to pick up. However, some key loggers work by capturing screen images at random intervals; these are known screen rec