COMPUTER SCIENCE

1. 5 INPUT AND OUTPUT
DEVICES
TOUCHSCREENS
SENSORS
INTERACTIVE
WHITEBOARDS.
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2. TOUCHSCREENS
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3. TOUCHSCREENS
• The touchscreen enables the user
• to interact directly
• with what is
• Displayed
• rather than using a mouse, touchpad,
other such devices ( other than a
stylus, which is optional for most
modern touchscreens).
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4. How does a touchscreen work?
• In screens that rely on sound or light
waves, your finger physically blocks or
reflects some of the waves. Capacitive
touch screens use a layer of capacitive
material to hold an electrical charge;
touching the screen changes the amount
of charge at a specific point of contact
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5. Who invented touch screen?
• Eric A. Johnson
• 1960s to 70s: Invention
• The first touchscreen was invented in 1965 by
Eric A. Johnson who worked at the Royal Radar
Establishment in Malvern, England. His first
article, "Touch display—a novel input/output
device for computers" describes his work and
features a diagram of the design
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6. What is a touchscreen used for?
• A touch screen is a display device that allows the user to interact
with a computer by using their finger or stylus. They're a useful
alternative to a mouse or keyboard for navigating a GUI (graphical
user interface)
• Advantages & Disadvantages of Touchscreen Technology
• -Touchscreen devices have limited buttons that will possibly break
after 3 – 4 years
• -Touchscreen devices usually have more simple user interfaces Ex.
Ipod Apps
• -Having less or not buttons means that you can put more effort into
having a big screen
• –For the people worried about hygiene, most devices are easy to
clean, some are even dirt, dust and grease resistant
• -For people new or uncomfortable with normal desktops,
touchscreens are easy to use helping more people get used to using
computers
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7. DISADVANTAGES
•
• -The screen has to be big enough to be able to touch the
buttons without missing
• -Having a big bright screen and needing massive computing
power to run this means a very low battery life
• -In direct sunlight it is much less efficient and most of the
time very difficult to read the screen
• -If a touchscreen devise were to crash the whole screen
would be unresponsive, and because of the lack of buttons
revering it would be very difficult
• -The screens will get very dirty
• -You have to be within arms reach of the device
• -They usually cost more than ordinary devices
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8. What is a touchscreen used for?
• A touch screen is a display device that allows the user to interact with a
computer by using their finger or stylus. They're a useful alternative to a
mouse or keyboard for navigating a GUI (graphical user interface)
• Advantages & Disadvantages of
Touchscreen Technology
• -Touchscreen devices have limited buttons that will possibly break after
• 3 – 4 years
• -Touchscreen devices usually have more simple user interfaces Ex. Ipod
Apps having less or not buttons means that you can put more effort into
having a big screen
• –For the people worried about hygiene, most devices are easy to clean,
some are even dirt, dust and grease resistant
• -For people new or uncomfortable with normal desktops, touchscreens are
easy to use helping more people get used to using computers
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9. What is the difference between
resistive and capacitive touch
screens?
• As opposed to the resistive touchscreen, which
relies on the mechanical pressure made by the
finger or stylus, the capacitive
touchscreen makes use of the fact that the
human body is naturally conductive. Capacitive
screens are made of a transparent, conductive
material—usually ITO—coated onto a glass
material.
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10. • Examples of current smartphones with resistive touchscreens
include:
• LG Optimus. LG GW620. Sony Ericsson Vivaz. ...
• Apple iPhone 3GS and Apple iPhone 4. HTC Desire. ...
• Tags smartphonesmobile phonesapple iphonetouch
screenssamsung galaxy sHTC Desire.
• More about AppleEricsson
AustraliaFacebookGalaxyHTCLGNokiaSamsungSonySony
Ericsson.
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11. What is an infrared touch screen?
• What is an infrared touch
screen?
• Infrared Touch Screen Technology. Learn
More. Infrared touch uses light emitting diodes and
sensors that are embedded in a bezel around
the display and emit and detect rows and columns
of infrared light across the face of the display.
•Why does capacitive touch only work with fingers?
• Unlike resistive touch screens, capacitive screens do not
use the pressure of your finger to create a change in the
flow of electricity. Instead, they work with anything that
holds an electrical charge – including human skin
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12. SENSORS
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13. • Sensors are sophisticated devices that are
frequently used to detect and respond to
electrical or optical signals.
• A Sensor converts the physical parameter
(for example: temperature, blood pressure,
humidity, speed, etc.) into a signal which can
be measured electrically
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14. WHAT IS sensor and types of
sensor?
• The most frequently used different types
of sensors are classified based on the
quantities such as Electric current or
Potential or Magnetic or Radio sensors,
• Humidity sensor, Fluid velocity or Flow
sensors, Pressure sensors, Thermal or Heat
or Temperature sensors, Proximity sensors,
Optical sensors, Position sensors.
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15. How do sensors work?
Basically there are two types of sensors:
active and passive. The sensor
working principle in each of these
devices varies to a certain extent.
These sensors use ultrasonic sound
waves to track any movement in the
specified range. The detectors emit
ultrasonic sound waves and wait for the
energy to be reflected back
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16. Why sensors are used?
A sensor is a device, module,
machine, or subsystem whose
purpose is to detect events or
changes in its environment
and send the information to
other electronics, frequently a
computer processor.
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17. ANALOGUE TO DIGITAL CONVERTER (ADC).
• Computers cannot make any sense of these physical quantities and the
data needs to be converted into a digital format.
• This is usually achieved by an ANALOGUE TO DIGITAL CONVERTER (ADC).
• This device converts physical values into discrete digital values.
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18. When the computer is used to control
devices, such as a motor or a valve, it
is necessary to use a DIGITAL TO
ANALOGUE CONVERTER (DAC) since
these devices need analogue data to
operate in many cases.
https://www.elprocus.com/analog-to-
digital-adc-
converter/#:~:text=Analog%20to%20
Digital%20Converter%20(ADC,sort%2
0of%20a%20binary%20number.
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19. Actuator
• An actuator is a component of a machine that is
responsible for moving and controlling a mechanism
or system, for example by opening a valve. In simple
terms, it is a "mover".
• An actuator requires a control signal and a
source of energy. The control signal is relatively low
energy and may be electric voltage or current,
pneumatic or hydraulic pressure, or even human
power. Its main energy source may be an electric
current, hydraulic fluid pressure,
or pneumatic pressure. When it receives a control
signal, an actuator responds by converting the
source's energy into mechanical motion.
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20. An ACTUATOR is used in these control
applications. Although these are technically
output devices, they are mentioned here since
they are an integral part of the control system.
An actuator is.
Table 5.2 contains number of common sensors and examples of
applications
Page 99-100 of text book
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21. solenoid is an example of a digital
actuator;
• An electromechanical device such as a relay, solenoid
or motor. Note that a solenoid is an example of a
digital actuator; part of the device is connected to a
computer which opens and closes a circuit as required.
When energized, the solenoid may operate a plunger
or armature to control, for example, a fuel injection
system. Other actuators, such as motors and valves,
may require a DAC so that they receive an electric
current rather than a simple digital signal direct from
the computer
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22. Sensorsare used in bothmonitoring and
control applications.
• Examples of monitoring include:
• Monitoring a patient in a hospital for vital signs
such as heart rate, temperature, etc.
• Monitoring of intruders in a burglar alarm
system.
• Checking the temperature levels in a car
engine.
• Monitoring pollution levels in a river.
• Figure 5.21 Monitoring/Control System
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23. Examples of control include
• Examples of control applications
• Turning streets light on at night and turning
them off again during daylight
• Regulating temperature in a central heating /air
conditioning system
• Changing the traffic lights at a road junction
• Operating anti-lock brakes on a car when
necessary
• Regulating the environment in a green house
• Figure 5.21 Monitoring/Control System
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24. Monitoring
Applications
https://www.which.co.uk/reviews/burglar-alarms-and-home-
security/article/burglar-alarms-and-home-security/burglar-alarms
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26. 8/22/2021
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27. Circuit Design of Burglar Alarm System
The IR transmitter or IR LED is connected to a
current limiting resistor of 150Ω and connected
to supply. It is placed at the maximum possible
range from photo diode.
The cathode of the photo diode is connected to
supply while anode is connected to 10KΩ resistor.
How do you build a burglar alarm
circuit?
https://getsafeandsound.com/2018/0
6/how-burglar-alarms-work/
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28. Types of burglar alarm systems
• Bells-only alarms make a noise, but don't contact
anyone (such as the police or you). Dialer burglar alarms
automatically dial your phone number, or that of
nominated friends and family, when the alarm is
triggered. Smart home-security systems contact you or
family members when the alarm goes off through a
smartphone or tablet app. A monitoring contract means
you pay a company monthly or annually to take action or
call the police if the alarm goes off.
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30. • An acoustic wave sensor is an electronic device that can measure
sound levels.
• They called acoustic wave sensors because their detection
mechanism is a mechanical (or acoustic) wave.
• What is an acoustic sound?
• Acoustics is the branch of physics concerned with the study
of sound (mechanical waves in gases, liquids, and solids). A scientist
who works in the field of acoustics is an acoustician. ... The ear itself
is another biological instrument dedicated to receiving certain wave
vibrations and interpreting them as sound
•
https://www.youtube.com/watch?v=MEVXZNlPrX4
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31. Infra red sensors
• An infrared sensor is an electronic instrument that is used to sense
certain characteristics of its surroundings. It does this by either emitting
or detecting infrared radiation. Infrared sensors are also capable of
measuring the heat being emitted by an object and detecting motion.
• How does the infrared sensor work?
• Active infrared sensors both emit and detect infrared radiation.
• Active IR sensors have two parts: a light emitting diode (LED) and a
receiver. When an object comes close to the sensor, the infrared light
from the LED reflects off of the object and is detected by the receiver.
• https://www.youtube.com/watch?v=zq51oZMzyP0
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32. What can IR sensors detect?
• An infrared sensor is an electronic instrument that is used to
sense certain characteristics of its surroundings. It does this by
either emitting or detecting infrared radiation. Infrared
sensors are also capable of measuring the heat being emitted
by an object and detecting motion.
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33. Pressure Sensor
• What is pressure sensor and how it works?
• A works by converting pressure into an analogue electrical
signal. The demand for pressure measuring instruments
increased during the steam age. ... Nowadays we
measure pressure electronically using pressure
transducers and pressure switches
• What does a pressure sensor detect?
• A pressure sensor is a device for pressure measurement of
gases or liquids. Pressure is an expression of the force
required to stop a fluid from expanding, and is usually stated
in terms of force per unit area. A pressure sensor usually acts
as a transducer; it generates a signal as a function of
the pressure imposed.
https://www.youtube.
com/watch?v=iru8tRw
S7Yc
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34. Monitoring of patients in
hospital
In hospitals sensors are a form of electronic-
based medical equipment used in almost all
areas of medical practice. Their main
function is to convert various forms of stimuli
into electric signal for analysis that can be
used to assist with surgery, scans, or
diagnosing a patient.
They can be used in CT and MRI scans to pick
up complex signals that give doctors a full
view of the patient’s body.
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35. Types of Sensors and their
Uses
•
They are often used to monitor pulse rate, temperature,
breathing rate, blood oxygen and blood pressure. Examples of
different sensors and their uses include:
• Biosensors – scans during pregnancy/ultrasound
• Pressure sensors – oxygen concentrators
• Temperature sensors – ventilators Image sensors – cardiology
Some sensors need to be especially small, lightweight, and
compatible with body mass, and require very little power to
operate correctly, for instance implantable sensors.
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36. Advantages of Sensors in
Hospitals
•
They can allow for a complete view of a patient’s body, which assists
with surgery and finding a diagnosis. T hey help monitor different
aspects of a patient’s health, which allows doctors to keep track of
their condition and whether it improves or worsens.
• Wireless Sensor Networks in Hospitals
A wireless sensor network uses distributed automatic sensors to
monitor physical or environmental conditions, such as temperature,
sound, or pressure, and then pass their data through a network to
one central location.In hospitals, there are two types of sensor
networks used: wearable and implanted. Wearable devices are used
externally - on the body surface of a human or just at close proximity
of the person. Implanted are those that work from inside the body,
where they have been inserted. They are used to collect information
about a person’s health, fitness and energy.
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37. Control
Applications
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38. Control Applications
• Control of street lighting
• Traditional street light control systems only support
manual control, photosensitive control, and simple
timing control while the energy utilization rate is low and the
operators cannot monitor the working state of
the street lights in real time, which causes great
inconvenience to management and maintenance.
• https://www.youtube.com/watch?v=YKzeSwjcqKM
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39. 8/22/2021
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40. Activity 5.6
Draw a flow diagram to show the steps in how a microprocessor
controls the switching off and on of a street lamp. Remember to
include a method to stop the lamp switching on and off every
few seconds.
• Take the help from the link below
https://www.google.com/search?q=block+diagram+of+street+li
ght+control&rlz=1C1AVUA_enPK906PK906&hl=en&sxsrf=ALeKk
01lyMah3lGqz1dgh8pqEDsDZkG5ug:1594194886922&tbm=isch
&source=iu&ictx=1&fir=9f0EaY7RRCw6aM%252CPWJszuzGM5e
P_M%252C_&vet=1&usg=AI4_-
kRyAOYrXow_njNPdpG1jsbxGrhvCw&sa=X&ved=2ahUKEwid7L_f
lr3qAhWDDewKHUG8BfIQ9QEwAXoECAoQHg&biw=1366&bih=
586
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41. Anti-lock Braking System (ABS)
• The anti-lock braking system (ABS) comes as a standard
safety feature in all modern cars. ... This is where the anti-lock
braking system (ABS) comes in. It prevents the wheels
from locking up and helps them maintain grip with the road
below. ABS was first introduced as an anti-skid system for
aircraft use in the 1950s
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42. 8/22/2021
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43. 8/22/2021
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44. Activity 5.7
•Find out more details about
how the ABS system works and
how it is modified in modern
systems such as traction
control.Investigate other uses
of magnetic field sensors.
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45. INTERACTIVE
WHITEBOARD
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46. What do interactive whiteboards do?
• An interactive whiteboard is a tool that allows multiple people
to engage in a collaborative experience using a touchscreen to
take notes, annotate content, and more. Many interactive
whiteboards offer on-board programs that help to facilitate
sharing and collaboration.
What is smart interactive whiteboard?
• An interactive whiteboard, also known as a smartboard, is
an interactive display in the format of a whiteboard that reacts
to user input either directly or through other devices. ... They
can play various types of media and provide teachers
with interactive lessons for their students.
INTERACTIVE WHITEBOARD
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47. INTERACTIVE WHITEBOARD
What are the advantages of interactive whiteboards?
• Here Are Main Advantages of Interactive Whiteboard：
• Improves Learning among Students and Employees. ...
• Increases Engagement among Meeting Participants. ...
• Enhances Collaboration. ...
• Facilitates Better Communication. ...
• Allows For Effective Annotation of Documents. ...
• Allows For Interconnectivity with Mobile Devices.
• https://www.youtube.com/watch?v=lLxVjw1yvRk
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48. 6 Best Interactive Whiteboards
• Best Interactive Whiteboards.
• Elite Screen
WB6BU. https://www.youtube.com/watch?v=3yicKzbz050
• GoTouch
Basichttps://www.horion.com/en/goods/ifp1?id=1&gclid=Cj0KCQjwl4
v4BRDaARIsAFjATPmxH_oqRTlO3I3k2_YQMi-
FgeZlXkDWLzVOxlPlFVvHUklpiAixgIkaAl39EALw_wcB
• Smart Tech Smart Board M600.
https://support.smarttech.com/docs/hardware/interactive-
whiteboards/smart-board-m600-and-m600v/en/home.cshtml
• eBeam Smartmarker Complete.
• Astar AWB-6,501.
• IGCSE Computer Science Tutorial: 1.3.3 (j) – Interactive Whiteboards
https://www.youtube.com/watch?v=IO9XjIoVX5M
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49. Bye Bye
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