Computer Science 455

Instructor: R. P. Burton

First Quiz

January 22-23,2008

Name _________________________________________ Score ____________/40

1. Due in large part to the appeal of pictures over text, computer graphics was accepted widely by the marketplace within less than a year of Ivan Sutherland’s pioneering work during the early 1960s.
1. true
2. false

(b)

2. Which of the following was the most significant impediment to the wider use of computer graphics following Sutherland’s work?
1. the development of suitable output devices
2. the development of suitable input devices
3. processor speeds and memory capacities
4. the acceptance of technology by the “arts” community

(c)

3. CAD applications of computer graphics are limited to
1. shape specification
2. functional and performance evaluation
3. ingress and egress evaluation (getting in and out)
4. (not limited to just one of the above)

(d)

4. Which is the most likely candidate for a computer simulator?
1. a crane used to load and unload ships
2. a bullet bike
3. a unicycle

(a)

5. Unfortunately, while computers can be used to designing machine parts, they do not lend themselves readily to producing machine parts.
1. true
2. false

(b)

6. Computer architecture was applied first to
1. residences
2. large buildings

(b)

7. Graphics techniques for producing graphs, charts, etc. were accepted by the marketplace early-on because of the ease with which the average person can read date from graphs, charts, etc.
1. true
2. false

(b)

8. The entertainment animation industry not only welcomed the advent of computer graphics; it invested heavily in its initial development.
1. true
2. false

(b)

9. Computer graphics can be used to produce images which might be visible to the human eye (even from locations which the human eye can not practically or safely access), but does not extend to the production of images which would never be visible to the human eye.
1. true
2. false

(b)

10. Graphical user interfaces represent
1. a subdiscipline relative to computer graphics
2. an application of computer graphics
3. a discipline separate from computer graphics

(b)

11. The CRT was
1. in existence and in widespread use prior to the advent of computer graphics
2. developed in parallel with (but independent of) computer graphics
3. developed specifically to provide output from computer graphics systems

(a)

12. A cathode ray is a stream of
1. electrons
2. protons
3. photons
4. positrons
5. muons

(a)

13. Light is emitted from a cathode ray tube when
1. the cathode ray – a stream of photons – passes through the glass surface of the cathode ray tube
2. the cathode ray – a stream of protons – strikes the phosphor which ultimately results in the emission of photons
3. the cathode ray – a stream of electrons – strikes the phosphor which ultimately results in the emission of photons
4. (none of the above)

(c)

14. In general, the longer the persistence of the phosphors, the better.
1. true
2. false

(b)

15. Given the following matrices

a b c d e f

h i j x k l m

n o p q r s

what value is in the first row and third column of the resulting matrix?

1. aq + br + cs
2. af + bm + cs
3. nd + oe + pf
4. cd + je + pf
5. (none of the above)

(b)

16. If A, B, and C are 4 x 4 matrices
1. (AB)C = A(BC)
2. AB = BA
3. Both (a) and (b) are true
4. Neither (a) nor (b) is true in general

(a)

17. Moving a problem to a higher dimensional space
1. always adds a level of complexity to the solution
2. sometimes reduces the complexity of the solution

(b)

18. Of the following phenomena, which occurs first?
1. fluorescence
2. phorphorescence
3. refresh

(a)

19. Two points (on a vector CRT) appear to overlap if and only if the electron distribution (and subsequent photon emission) overlap.
1. true
2. false

(b)

20. If the display is 100 x 100 and 1000 different colors can be presented, how many bits is the frame buffer?
1. 100 x 100 x 1000
2. 100 x 100 x 100
3. 100 x 100 x 10
4. 100 x 100

(c)

21. In a random scan display, there are problems if it takes more than 1/30^th of a second to traverse the display list, but there is no problem with refreshing too often.
1. true
2. false

(b)

22. In a beam penetration CRT, the electron beam doesn’t always (meaningfully) penetrate all the phosphor layers.
1. true
2. false

(a)

23. The shadow mask in a shadow mask CRT
1. permits each electron gun to strike only certain phosphor dots
2. “focuses” the electron beam, making a smaller spot
3. both (a) and (b)
4. neither (a) nor (b)

(c)

24. Shadow mask CRTs sometimes have lines of color dots rather than triads of color dots.
1. true
2. false

(a)

25. If you add the number of electron guns to the number of deflection systems to the number of focusing systems for a direct view storage tube, the sum is
1. three
2. four
3. five
4. six
5. more than six

(c)

26. Which of the following is an advantage of the plasma panel?
1. multiple colors
2. selective erasure
3. the time required to change the state of a cell
4. resolution
5. (all are advantages of the plasma panel)

(b)

27. Which direction do the (thread-like) liquid crystals run in a liquid crystal display?
1. horizontally
2. vertically
3. both horizontally and vertically
4. perpendicular to the display surface

(d)

28. Which of the following is NOT a characteristic of an LED display?
1. multiple colors
2. selective erasure
3. “pixels” on and off faster than a plasma panel
4. (all are advantages of LED displays)

(d)

29. All of the following produce two (or more) 2D images which the mind merges into a 3D image EXCEPT
1. varifocal mirrors
2. polarized projection systems
3. shuttered systems
4. random-dot autostereograms
5. head mounted displays
6. (no exceptions here)

(f)

30. All of the following produce two (or more) 2D images which the mind merges into a 3D image EXCEPT
1. holograms
2. rotating LED panels
3. ViewMaster ® systems
4. stereolithographic systems
5. (no exceptions here)

(d)

31. Double buffering is most likely to be used
1. for systems which need more than 1/30^th of a second to compute the next frame
2. for systems which must produce separate left-eye and right-eye images
3. for system which must produce 3D images
4. for systems with liquid crystal output devices

(a)

32. A significant, unresolved deficiency of the (hand-held) mouse is that the intended movement of the mouse is not always sensed, resulting in discontinuities in the input and/or interruptions in the input.
1. true
2. false

(b)

33. A truly “isometric” input device, such as a joystick or spaceball that does not move at all (responding instead to pressure applied by the user) is less satisfactory than an input device which moves at least slightly, even if the associated displacement is not used in any way to determine user input.
1. true
2. false

(a)

34. Data glove input is provided
1. optically (but outside the human visual range)
2. electromagnetically
3. acoustically (but outside the human audible range)

(b)

35. If you have a tablet consisting of 1000 embedded vertical wires and 1000 embedded horizontal wires, each capable of carrying a signal consisting of one or more bits, what is the minimum of bits needed in the signal if the horizontal and vertical position of a (“listening”) stylus is to be determined?
1. 1
2. 2
3. 10
4. 11
5. 20

(a)

36. Which of the following is closest to the locus of points equidistant from a strip microphone (such as might be associated with a tablet)?
1. a circle
2. a sphere
3. a line
4. a plane
5. a cylinder

(e)

37. Which of the following lends itself best to the detection and tracking of two simultaneous points on a “touch screen?”
1. optical techniques
2. electromagnetic techniques
3. acoustical techniques

(a)

38. How does the light pen leave a “trail” of light on a screen?
1. it writes to a storage grid which permits electrons from a flood gun to pass through
2. it interrupts perpendicular LED beams, revealing its position
3. it’s position is sensed by light emitted from the screen and saved for subsequent refresh

(c)

39. For which of the following logical activities would a voice input system be most applicable?
1. valuating
2. locating
3. stroking
4. picking

(d)

40. Approximately what percent of the logical input devices discussed in class can be modeled by ANY of the physical input devices discussed in class?
1. 10%
2. 50%
3. 75%
4. 100%

(d)