Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Computer Science > Chapter 3.2 A - Input devices FINAL BOARDS > Flashcards

Chapter 3.2 A - Input devices FINAL BOARDS Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

What is a barcode

A

a series of dark and light parallel lines of varying thickness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What happens after the barcode is read (supermarket)

A

The barcode is looked up in stock database

When the barcode number is found, the stock item record is looked up

The price and other stock item details are sent back to the checkout or the POS

the number of stock items in the record is reduced by 1 each time the barcode is read

this new value for number of stock is written back to the stock item record

the number of stock items is compared to the re-order level; if it is less than or equal to this value, more stock items are automatically ordered

once an order for more stock items is generated, a flag is added to the record to stop re-ordering every time the stock item barcode is read

when new stock items arrive, the stock levels are updated in the database.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a key field

how does it relate to a barcode

A

the field that uniquely identifies a record in a file

barcode acts as a key field for items in a supermarket

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the POS

A

point of sales terminal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Advantages of barcodes (managers)

A

Automatic stock control

More up-to-date sales information and sales trends

Much faster and easier to change prices on stock items

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Advantages of barcodes (customer)

A

Faster checkout queues

Errors in billing are reduced

An itemized bill is given to the customer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a QR code

A

a matrix of dark and light squares which represent data

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Full form of QR

A

Quick Response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How can a QR code be read

A

QR code apps and smart phone cameras

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Common uses of QR codes

A

Advertising
Restaurant menus
Storing boarding passes of flights and trains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Advantages of QR code compared to Bar code

A

More information

Few errors - QR Codes have a built in error checking systems. This helps guard against badly printed, damaged QR codes

Easy to read - don’t need a laser or an led light source

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Disadvantages of QR codes

A

Can be used to transfer malicious codes. It is very easy to embed malicious code into a QR code. This code could be a virus, etc.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the process of transferring malicious codes through a QR code called

A

Attaging

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is a Frame QR code

A

a type of QR code that includes a space for advertising

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What colour system do most cameras use

A

24-bit RGB Colour system - 3 primary colours, each get 8 bits.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does the number of pixels in the picture determine

A

size of the file used to store the photograph

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What does the quality of the image (camera) depend on

A

Recording device (how good the camera lens is and how good the sensor array is)

Number of pixels used (the more pixels used, the better the image)

Levels of light and how the image is stored (JPEG, raw file, png, etc)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is a DAC (full form and def)

A

Digital to analogue converter - device that converts digital data into electric currents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is a virtual keyboard

A

an onscreen keyboard which uses the features of the touch screen to emulate a physical keyboard

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How does an ergonomic keyboard tackle RSI

A

these have the keys arranged differently

They are also designed to give more support to the wrists and hands when doing a lot of typing.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is RSI (full form and def)

A

repetitive strain injury - pain felt in the muscles,
nerves and tendons caused by a repetitive action (for
example

22
Q

What does a microphone do

A

Converts sound waves into an electric current. The current is then converted to a digital format so that the computer can process/store it

23
Q

What is the nature of the current gen by the microphone

A

analogue

24
Q

What is a CMOS (full form and func)

A

complementary metal oxide semiconductor - a chip that generates an electric current when light falls on its surface

25
Q

What is a DSP (optical mouse)

A

digital signal processor - a processor that calculates, the coordinates of a pointing device based on the pulses of electricity received

26
Q

Why an optical mouse is better than a mechanical mouse

A

No moving parts - more durable

Dirt can’t get trapped in any of the mechanical components

No special surfaces are required

27
Q

Advantages of wired connections over Bluetooth and wireless (mouse)

A

No signal loss - consistent pathway

Cheaper to operate - no need to buy batteries over and over again

28
Q

What is a 2D scanner

A

Most common form of scanners that are used to input hard copy (paper) documents

29
Q

What is an OCR (full form and function)

A

Optical character recognition - Technology that can convert hard copy text or images into a digital format such as a text file that is to be stored in a computer memory

30
Q

What is a 3D scanner

A

Scan solid objects and produce a three-dimensional image.

Take images on several different points along the X, Y and Z coordinates.

31
Q

Where can the images from a 3D scanner be used to design and create

A

CAD - computer aided design which is a software used to create drawings

32
Q

What is a application of a 3D scanner

A

Computed tomographic scanners.

33
Q

What does a CT scanner do

A

used to create a 3D image of a solid object

34
Q

What is a touchscreen

A

Allows the user to select or manipulate a screen image using the touch of a finger or stylus

35
Q

3 Types of touchscreen

A

resistive
Capacitive
Infrared

36
Q

Two types of capacitive screens

A

Surface

Projective

37
Q

Surfaces that can control a surface capacitive screen

A

bare fingers

stylus

38
Q

surfaces that can control a projective capacitive screen

A

bare fingers
stylus
thin surgical or cotton gloves

39
Q

What other facilities does a projective capacitive screen allow for

A

Multi-touch

40
Q

Advantages of capacitive screens compared to others

A

Better img quality comp to resistive

Durable

Projective allow multi touch

41
Q

Disadvantages of capacititive screens comapred to others

A

Surface capacitive screens only work with bare fingers or stylus

This screen is sensitive to electromagnetic radiation

42
Q

What is an infrared touch screen

A

Infrared touch screens use a glass screen with an array of sensors and infrared transmitters

43
Q

Advantages of infrared touch screens comp to others

A

Multi-touch

good durability

operability isn’t affected by a scratched or cracked screen

44
Q

Disadv of infrared touch screens comp to others

A

Screen is sensitive to water and moisture

Accidental activation can take place if beams are broken by any other objects or are disturbed in someway.

Could be sensitive to light interferance

45
Q

What is a resistive touch screen

A

made up of two layers of electrically resistive material with a voltage applied across them

46
Q

Adv of resistive touch screens comp to others

A

Good resistance to dust and water

Can be used by bare fingers, stylus and gloved hands

47
Q

Disadv of resisitive touch screens comp to others

A

Low touch sensitivity

Doesn’t allow multi-touch

Poor visibility in strong sunlight

Vulnerable to scratches on the screen

48
Q

What control cameras

A

an embedded system

49
Q

What does the embedded system in cameras control?

A

» adjust the shutter speed
» focus the image automatically
» operate the flash gun automatically
» adjust the size of the image
» remove ‘red eye’ when the flash gun has been used

50
Q

How are 2D scanners used in airports

A

two-dimensional photograph in the passport is scanned and stored as a JPEG image.
Picture of passengers face is taken via a camera
Key characteristics of face are compared using face recog/detection software

51
Q

What are the key characteristics of faces that are compared in 2D scanner airport application

A

» distance between the eyes
» width of the nose
» shape of the cheek bones
» length of the jaw line
» shape of the eyebrows

52
Q

Use and full forms of

CT
MRI
SPECT

A

computerised tomography - X-ray

MRI - magnetic resonance images - Radio frequencies

single photon emission computer tomography - gamma rays

Computer Science (28 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions