Teacher : Seyyed Kamran Hosieni

Class Assistant : Ehsan Azizi

15 / May / 2022
1
Review
 Three major processes involved in memory?(Explain
each)
 Three types of memory or memory function?
 Productive /Reproductive thinking ?
 Why did we talk about human emotions?
 Why is it important to think?

2
Plan :
Introduction

1. Text entry devices

2. Positioning, pointing and drawing

3. Devices for virtual reality and 3D interaction

4. Physical controls, sensors and special devices

5. Paper: printing and scanning

6. Memory

3
 1. INTRODUCTION

a computer system is made up of various elements

each of these elements affects the interaction

– input devices – text entry and pointing

– output devices – screen (small&large), digital paper
– virtual reality – special interaction and display
devices
– physical interaction – e.g. sound, haptic, bio-
sensing
– paper – as output (print) and input (scan)
– memory – RAM & permanent media, capacity &
access
– processing – speed of processing, networks
4
 1. INTRODUCTION

to understand human–computer interaction

… need to understand computers!

what goes in and out

devices, paper,
sensors, etc.

what can it do?

memory, processing,
networks

5
 1. INTRODUCTION
A ‘typical’ computer system:
• screen, or monitor, on which there are windows
• keyboard
window 1
• mouse/trackpad
window 2

• variations
– desktop
– laptop 12-37pm

– PDA

the devices dictate the styles of interaction that the

system supports
If we use different devices, then the interface will
support a different style of interaction 6
 1. INTRODUCTION

 Computers are coming out of the box!

 Information appliances are putting internet access or

dedicated systems onto the fridge, microwave and washing
machine: to automate shopping, give you email in your
kitchen or simply call for maintenance
when needed.
 We carry with us WAP phones and smartcards, have
security systems that monitor us and web cams that show
our homes to the world.
7
 1. TEXT ENTRY DEVICES

keyboards
chord keyboards, phone pads
handwriting, speech

8
 1. TEXT ENTRY DEVICES : keyboards
 The keyboard is still one of the most common input
devices in use today.

 Allows rapid entry of text by experienced users

 Usually connected by cable, but can be wireless

 It is used for entering textual data and commands. The vast
majority of keyboards have a standardized layout, and are
known by the first six letters of the top row of alphabetical
keys, QWERTY.

9
 1. TEXT ENTRY DEVICES: The alphanumeric keyboard:

The QWERTY keyboard:

• Standardised layout

but …
– non-alphanumeric keys are placed differently

– accented symbols needed for different scripts

– minor differences between UK and USA keyboards

• QWERTY arrangement not optimal for typing

– layout to prevent typewriters jamming!
• Alternative designs allow faster typing but large social base of
QWERTY typists produces reluctance to change.
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 1. TEXT ENTRY DEVICES: The alphanumeric keyboard:

alphabetic keyboard :
– keys arranged in alphabetic order

– not faster for trained typists

– not faster for beginners either!

 DVORAK:
– common letters under dominant fingers
– biased towards right hand
– common combinations of letters alternate between
hands
– 10-15% improvement in speed and reduction in fatigue
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 1. TEXT ENTRY DEVICES: The chord keyboard

 Only a few keys, four or five, are used and letters are
produced by pressing one or more of the keys at once.

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 1. TEXT ENTRY DEVICES: Phone pad and T9 entry:

• use numeric keys with

multiple presses
2–abc 6-mno
3-def 7-pqrs
4-ghI 8-tuv
5-jkl 9-wxyz

hello = 4433555[pause]555666

surprisingly fast!

13
 1. TEXT ENTRY DEVICES: Phone pad and T9 entry:

• T9 predictive entry

– type as if single key for each letter

– use dictionary to ‘guess’ the right word

– hello = 43556 …

14
 1. TEXT ENTRY DEVICES: Handwriting recognition:

• Text can be input into the computer, using a pen and a digesting
tablet
– natural interaction

• Technical problems:
– segmenting joined up writing into individual letters

– interpreting individual letters

– coping with different styles of handwriting

• Used in PDAs, and tablet computers …

… leave the keyboard on the desk!

15
 1. TEXT ENTRY DEVICES: Speech recognition:

• Improving rapidly

• Most successful when:

– single user – initial training and learns peculiarities
– limited vocabulary systems

• Problems with
– external noise interfering
– imprecision of pronunciation
– large vocabularies
– different speakers

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 1. TEXT ENTRY DEVICES: numeric keypads:

• for entering numbers quickly:

– calculator, PC keyboard

• for telephones.
1 2 3 7 8 9

4 5 6 4 5 6

7 8 9 1 2 3

.
* 0 # 0 =

Telephone Calculator

17
2. POSITIONING, POINTING AND DRAWING :

mouse, touchpad
trackballs, joysticks ,
touch screens, tablets
cursors

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 2. POSITIONING, POINTING AND DRAWING :

•Central to most modern computing systems is the ability

to point at something on the screen and manipulate it
• There has been a long history of such devices, in
particular in computer-aided design (CAD), where
positioning and drawing are the major activities.
•Pointing devices allow the user to point, position and
select items, either directly or by manipulating a pointer on
the screen.
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Computer-aided design
 CAD, or computer-aided design and drafting (CADD),
is technology for design and technical
documentation, which replaces manual drafting with
an automated process. If you're a designer, drafter,
architect, or engineer, you've probably used 2D or 3D CAD
programs such as AutoCAD or AutoCAD LT software.

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 2. POSITIONING, POINTING AND DRAWING :

•Many pointing devices can also be used for free-hand

drawing although the skill of drawing with a mouse is
very different from using a pencil.
•The mouse is still most common for desktop computers,
but is facing challenges as laptop and handheld
computing increase their market share.

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 2. POSITIONING, POINTING AND DRAWING :
The mouse

• Handheld pointing device

– very common
– easy to use

• Two characteristics
– planar movement
– buttons
(usually from 1 to 3 buttons on top, used for making a
selection, indicating an option, or to initiate
drawing etc.)

22
 2. POSITIONING, POINTING AND DRAWING :
The mouse
How does it work?

• Mechanical:
– Ball on underside of mouse turns as mouse is moved
– Can be used on almost any flat surface

• Optical:
– light emitting diode on underside of mouse
– may use special grid-like pad or just on desk
– less susceptible to dust and dirt

23
 2. POSITIONING, POINTING AND DRAWING :
The touchpad

• small touch sensitive tablets

• ‘stroke’ to move mouse pointer

• used mainly in laptop computers

• good ‘acceleration’ settings

– fast stroke
• lots of pixels per inch moved
• initial movement to the target
– slow stroke
• less pixels per inch
• for accurate positioning
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 2. POSITIONING, POINTING AND DRAWING :
Trackball and thumbwheels

 Trackball :
– ball is rotated inside static housing
• like an upsdie down mouse!
– relative motion moves cursor
– indirect device, fairly accurate
– separate buttons for picking
– very fast for gaming
– used in some portable and notebook computers.

 Thumbwheels :
– for accurate CAD
– for fast scrolling

25
 2. POSITIONING, POINTING AND DRAWING :
Joystick and keyboard nipple

 Joystick :
– Indirect pressure of stick
= velocity of movement
– buttons for selection
on top or on front like a trigger
– often used for computer games,
aircraft controls and 3D navigation

 Keyboard nipple :
– for laptop computers
– miniature joystick in the middle
of the keyboard

26
 2. POSITIONING, POINTING AND DRAWING :
Touch-sensitive screen
• Detect the presence of finger or stylus on the screen.
– works by interrupting matrix of light beams, capacitance changes or
ultrasonic reflections
– direct pointing device

• Advantages:
– fast, and requires no specialized pointer
– good for menu selection
– suitable for use in hostile environment:
clean and safe from damage.

• Disadvantages:
– finger can mark screen
– imprecise (finger is a fairly blunt instrument!)
• difficult to select small regions or perform accurate drawing
– lifting arm can be tiring 27
 2. POSITIONING, POINTING AND DRAWING :
Stylus and light pen

 Stylus
– small pen-like pointer to draw directly on screen
– use touch sensitive surface or magnetic detection
– used in PDA, tablets PCs and drawing tables

 Light Pen
– now rarely used
– uses light from screen to detect location

BOTH …
– very direct and obvious to use
– but can obscure screen
28
 2. POSITIONING, POINTING AND DRAWING :
Digitizing tablet

•Digitizing tablets are used for freehand drawing.

capable of high resolution, and are available in a range of
sizes.
•very accurate: used for digitizing maps

•Problems with digitizing tablets are that they require a

large amount of desk space, and may be awkward to use if
displaced to one side by the keyboard.
29
 2. POSITIONING, POINTING AND DRAWING :
Eye gaze

•allow you to control the computer by simply looking at it!

•Some systems require you to wear special glasses or a small head-
mounted box, others are built into the screen or sit as a small box below
the screen
•It is fine for selection but not for drawing.

• potential for hands-free control

• uses laser beam reflected off retina

• very fast and accurate device, but the more accurate versions can be
expensive.
30
 2. POSITIONING, POINTING AND DRAWING :
Cursor keys

• Four keys (up, down, left, right) on keyboard.

• Very, very cheap, but slow.

• Useful for not much more than basic motion for text-editing tasks.

• No standardised layout, but inverted “T”, most common

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5 Most Expensive Laptops in the World
2022
01. MJ’s Swarovski and Diamond Studded Notebook

32
5 Most Expensive Laptops in the World
2022

01. MJ’s Swarovski and Diamond Studded Notebook

Price: $3.5 Million
Brand: MJ
Brand Country: Ukraine
Launching Year: 2010
Design Inventor: Ukraine’s professional hardware engineers
Specialty: Surface encrusted with expensive white and black diamond as well as
gold, golden mouse, 10-year warranty, Snake and croc skin edition
Customer’s rating: 80% positive ratings

33
5 Most Expensive Laptops in the World
2022
02. Luvaglio

34
02. Luvaglio
Price: $1 Million
Brand: Luvaglio
Brand Country: London, UK
Launching Year: 2018
Amazing fact: Nobody bought this laptop yet
Specialty: diamonds in the surface, the body can be customized
with woods, blue-ray disc reader, fingerprint ignition, first
handcrafted
laptop, power button is made up with diamond, integrated screen
cleaning
Specification: 128 GB of hard drive, 17 inches LED screen, USB
slots

35
5 Most Expensive Laptops in the World
2022 03. MacBook Air Supreme

36
5 Most Expensive Laptops in the World
2022
 03. MacBook Air Supreme
 Price: $500K USD (Buy in cheap price)
Brand: Apple Inc.
Brand Country: USA
Launching Year: 2008
Design Developer: Apple Inc
Type: Subnotebook
Operating system: macOS
Specialty: Surface is coated with the platinum, machined
aluminum case, thin light structure, Intel Core i5
Customers review: 96% positive rating

37
5 Most Expensive Laptops in the World
2022
04. Tulip E-Go Diamond Notebook

38
04. Tulip E-Go Diamond Notebook
 Price: $355K USD
Brand: Tulip
Brand Country: Netherlands
Launched: 2005
Specification: 160 GB of hard disk, DVD burners, 12.1-
inch widescreen, 2 GB RAM
Attraction & Specialty: Designed with gold, ruby,
and high-quality brilliant-cut diamonds
Ratings: 90% good rating

39
5 Most Expensive Laptops in the World
2022
 05. MacBook Pro 24 Karat Gold

40
5 Most Expensive Laptops in the World
2022
 05. MacBook Pro 24 Karat Gold

 Price: $30K USD

Brand: Apple Inc.
Brand Country: USA
Launching Year: 2013
Specification: Processor Intel Core 2 Duo, Speed: 2.4GHz,
memory: 4Gb RAM, NVIDIA Geforce 8600m
GT Manufacturer: Computer Choppers
Design inventor: Choppers hardware’s engineers
Specialty: Surface is stripped with pure gold, repainting,
Diamond’s Apple logo on the top, powered by 2.4 GHz
Intel Core 2 Duo processor
Customers review: 89% positive review
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Break

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3. VIRTUAL REALITY AND 3D INTERACTION:

Positioning in 3D space
Moving and grasping
Seeing 3D (helmets and caves)

43
 3. VIRTUAL REALITY AND 3D INTERACTION:
Positioning in 3D space
• Cockpit and virtual controls
– steering wheels, knobs and dials … just like real!

• The 3D mouse
– six-degrees of movement: x, y, z + roll, pitch, yaw

• Data glove
– fibre optics used to detect finger position

• VR helmets
– detect head motion and possibly eye gaze

• Whole body tracking

– accelerometers strapped to limbs or reflective dots and video processing
44
 3. VIRTUAL REALITY AND 3D INTERACTION:
Positioning in 3D space

pitch, yaw and roll

yaw

roll
pitch

45
 3. VIRTUAL REALITY AND 3D INTERACTION:
3D displays

• desktop VR:

– ordinary screen, mouse or keyboard control

– perspective and motion give 3D effect

• seeing in 3D:

– use stereoscopic vision

– VR helmets

– screen plus shuttered specs, etc.

46
 3. VIRTUAL REALITY AND 3D INTERACTION:
3D displays

• VR headsets:
⁻ small TV screen for each eye
⁻ slightly different angles
⁻ 3D effect

47
4. PHYSICAL CONTROLS, SENSORS AND
SPECIAL DEVICES :

special displays and gauges

sound, touch, feel physical controls
environmental and bio-sensing

48
 4. PHYSICAL CONTROLS, SENSORS AND
SPECIAL DEVICES : Special displays

• analogue representations:
– dials, gauges, lights, etc.

• digital displays:
– small LCD screens, LED lights, etc.

• head-up displays:
– found in aircraft cockpits
– show most important controls

49
 4. PHYSICAL CONTROLS, SENSORS AND
SPECIAL DEVICES : Sounds

• beeps, bongs, clonks, whistles and whirrs

• used for error indications

• confirmation of actions e.g. Keyclick

50
 4. PHYSICAL CONTROLS, SENSORS AND
SPECIAL DEVICES : Touch, feel and smell

• touch and feeling important:

– in games … vibration, force feedback
– in simulation … feel of surgical instruments
– called haptic devices

• texture, smell, taste:

– current technology very limited

51
 4. PHYSICAL CONTROLS, SENSORS AND
SPECIAL DEVICES : Environment and bio-sensing

• sensors all around us

– car courtesy light – small switch on door
– ultrasound detectors – security,
– RFID security tags in shops
– temperature, weight, location

• … and even our own bodies …

– iris scanners, body temperature, heart rate, galvanic
skin response, blink rate 52
 5. PAPER: PRINTING AND SCANNING

print technology
fonts, page description, WYSIWYG
scanning, OCR

53
 5. PAPER: PRINTING AND SCANNING
Printing

• image is made from small dots

– allows any character set or graphic to be printed,

• critical features:
– resolution

• size and spacing of the dots

• measured in dots per inch (dpi)

– speed

• usually measured in pages per minute 54

 5. PAPER: PRINTING AND SCANNING
Types of dot-based printers
• dot-matrix printers :
– use inked ribbon (like a typewriter)
– line of pins that can strike the ribbon, dotting the paper.
– typical resolution 80-120 dpi

• ink-jet and bubble-jet printers :

– tiny blobs of ink sent from print head to paper
– typically 300 dpi or better .

• laser printer :
– like photocopier: dots of electrostatic charge deposited on
drum, which picks up toner (black powder form of ink) rolled
into paper which is then fixed with heat
– typically 600 dpi or better.
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 5. PAPER: PRINTING AND SCANNING
Printing in the work space

• shop tills :
– dot matrix
– may print cheques
– same print head used for several paper rolls

• thermal printers :
– special heat-sensitive paper
– paper heated by pins makes a dot
– used in some fax machines
– poor quality, but simple & low maintenance
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 5. PAPER: PRINTING AND SCANNING
Fonts

• Font – the particular style of text

Courier font
Helvetica font
Palatino font
Times Roman font
 (special symbol)

• Size of a font measured in points (1 pt about 1/72”)

(vaguely) related to its height
This is twenty-four point Harlow solid italic
This is eighteen point
This is twelve point

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 5. PAPER: PRINTING AND SCANNING
Fonts

 Pitch
– fixed-pitch – every character has the same width
e.g. Courier
– variable-pitched – some characters wider
e.g. Times Roman

• Serif or Sans-serif
– sans-serif – square-ended strokes
e.g. Helvetica
– serif – with splayed ends (such as)
e.g. Times Roman or Palatino
58
 5. PAPER: PRINTING AND SCANNING
Readability of text

• lowercase
– easy to read shape of words

• UPPERCASE
– better for individual letters and non-words
e.g. flight numbers: BA793 vs. ba793

• serif fonts
– helps your eye on long lines of printed text
– but sans serif often better on screen
59
 5. PAPER: PRINTING AND SCANNING
Screen and page

• WYSIWYG
– what you see is what you get
– aim of word processing, etc.
• but …
– screen: 72 dpi, landscape image
– print: 600+ dpi, portrait
• can try to make them similar
but never quite the same
• so … need different designs, graphics etc, for screen
and print
60
 5. PAPER: PRINTING AND SCANNING
Scanners

•Printers take electronic documents and put them on

paper – scanners reverse this process.
•The image to be converted may be printed, but may also
be a photograph or hand-drawn picture.
•There are two main kinds of scanner:
Flat-bed: hand-held:

61
 5. PAPER: PRINTING AND SCANNING
Scanners

•Scanners work by shining a beam of light at the page

and then recording the intensity and color of the
reflection.
•Like photocopiers, the color of the light that is shone
means that some colors may appear darker than
others on a monochrome scanner.
•Like printers, scanners differ in resolution,
commonly between 600 and 2400 dpi
62
 6. MEMORY:

•Like human memory, we can think of the computer’s

memory as operating at different
levels, with those that have the faster access typically
having less capacity.
•By analogy with the human memory, we can group
these into short-term and long-term memories (STM
and LTM).
63
 6. MEMORY: RAM and short-term memory (STM)

Most currently active information is held in silicon-chip

Random Access Memory (RAM).
Typical access times are of the order of 10 nanoseconds,
that is a hundred-millionth of a second.
Information can be accessed at a rate of around 100
Mbytes (million bytes) per second.
Typical storage in modern personal computers is
between 64 and 256 Mbytes.
Its contents are lost when the power is turned off.
64
 6. MEMORY: Disks and long-term memory (LTM)

There are two main kinds of technology used in disks:

magnetic disks and optical disks.
 Magnetic disks: The most common storage media,
floppy disks and hard (or fixed) disks, are coated with
magnetic material, like that found on an audio tape, on
which the information is stored.
 Optical disks: use laser light to read and (sometimes)
write the information on the disk. There are various high
capacity specialist optical devices, but the most common
is the CD-ROM.
65