Autor: Info &amp; Fun | Publicado: 2011-11-21T02:43:00-08:00


Input / Output decives       
 

EXERCISE 2.1



Individually or in a group find as many    different examples as you can of physical controls    and displays.
(a) List them
(b) Try to group them, or classify them.
(c) Discuss whether you believe the control or display    is suitable for its purpose. (section 3.9.3 may also    help)



answer

open-ended investigation




EXERCISE 2.2

Exercises 2.2 and 2.3 involve you examining    a range of input and output devices in order to understand    how they influence interaction.

A typical computer system is comprised    of a QWERTY keyboard, a mouse, and a colour screen.    There is usually some form of loudspeaker as well.    You should know how the keyboard, mouse and screen    work - if not, read up on it. 

What sort of input does the keyboard    support? What sort of input does the mouse support?    Are these adequate for all possible applications?    If not, to which areas are they most suited? Do these    areas map well onto the typical requirements for users    of computer systems?

If you were designing a keyboard for    a modern computer, and you wanted to produce a faster,    easier to use layout, what information would you need    to know and how would that influence the design?



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EXERCISE 2.3

Pick a couple of computer input devices    that you are aware of (joystick, light pen, touchscreen,    trackball, eyegaze, dataglove, etc.) and note down    how each has different attributes that support certain    forms of interaction. You ought to know a little about    all of these devices - if you do not, research    them.



answer

open-ended investigation




EXERCISE 2.4

What is the myth of the infinitely fast    machine?



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EXERCISE 2.5

Pick one of the following scenarios,    and choose a suitable combination of input and output    devices to best support the intended interaction.    It may help to identify typical users or classes of    user, and identify how the devices chosen support    these people in their tasks. Explain the major problems    that the input and output devices solve. 

Environmental database

A computer database is under development    that will hold environmental information. This ranges    from meteorological measurements through fish catches    to descriptions of pollution, and will include topographical    details and sketches and photographs. The data has    to be accessed only by experts, but they want to be    able to describe and retrieve any piece of data within    a few seconds.

Word processor for blind people

A word processor for blind users is needed,    which can also be operated by sighted people. It has    to support the standard set of word-processing tasks.  



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EXERCISE 2.6

Describe Fitts' Law (see chapter 1).    How does Fitts' Law change for different physical    selection devices, such as a 3-button mouse, a touchpad,    or a pen/stylus? (You'll need to do some research    for this.)



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Alunos : Gabriel Bezerra, Victória Lima, Josélia Pereira, Joyce Ferreira, Keyla Jesse, Érica Albergaria e Siméia Silva&nbsp; 

     

Individual exercises

ex.2.1 (open), ex.2.2 (tut), ex.2.3 (open), ex.2.4 (tut), ex.2.5 (tut), ex.2.6 (tut)

Worked exercises in book

&nbsp;&nbsp;
What input and output devices would you use for      the following systems? For each, compare and contrast      alternatives, and if appropriate indicate why the      conventional keyboard, mouse and CRT screen may      be less suitable. [page 105]
(a) portable word processor
(b) tourist information system
(c) tractor-mounted crop-spraying controller
(d) air traffic control system
(e) worldwide personal communications system
(f) digital cartographic system   


&nbsp;&nbsp;
What is the basic architecture of a computer    system? [page 114]


&nbsp;&nbsp;
How do you think new, fast, high-density    memory devices and quick processors have influenced    recent developments in HCI? Do they make systems any    easier to use? Do they expand the range of applications    of computer systems? [page 119]