UGC-NET CS 2017 Nov - III

Question 11

Given two relations R1(A, B) and R2(C, D), the result of following query

Select distinct A, B
from R1, R2

is guaranteed to be same as R1 provided one of the following condition is satisfied.

• R1 has no duplicates and R2 is empty.
• R1 has no duplicates and R2 is non - empty.
• Both R1 and R2 have no duplicates.
• R2 has no duplicates and R1 is non - empty.

Question 12

Consider a schema R(A, B, C, D) and following functional dependencies.

A → B
B → C
C → D
D → B

Then decomposition of R into R₁ (A, B), R₂(B, C) and R₃(B, D) is __________ .

• Dependency preserving and lossless join.
• Lossless join but not dependency preserving.
• Dependency preserving but not lossless join.
• Not dependency preserving and not lossless join.

Question 13

Which of the following is not a component of Memory tube display ?

• Flooding gun
• Collector
• Ground
• Liquid Crystal

Question 14

Which of the following is not true in case of Oblique Projections?

• Parallel projection rays are not perpendicular to the viewing plane.
• Parallel lines in space appear parallel on the final projected image.
• Used exclusively for pictorial purposes rather than formal working drawings.
• Projectors are always perpendicular to the plane of projection.

Question 15

With respect to CRT, the horizontal retrace is defined as:

• The path an electron beam takes when returning to the left side of the CRT.
• The path an electron beam takes when returning to the right side of the CRT.
• The technique of turning the electron beam off while retracing.
• The technique of turning the electron beam on/off while retracing.

Question 16

Find the equation of the circle x²+y²=1 in terms of x\'y\' coordinates, assuming that the xy coordinate system results from a scaling of 3 units in the x\' direction and 4 units in the y\' direction.

• 3(x\')² + 4(y\')² = 1
• (x\'/3)² + (y\'/4)² = 1
• (3x\')² + 4(y\')² = 1
• 1/3(x\')² + 1/4(y\')² = 1

Question 17

Find the normalization transformation that maps a window whose lower left corner is at (1, 1) and upper right corner is at (3, 5) onto a viewport that is the entire normalized device screen.

• (1)
• (2)
• (3)
• (4)

Question 18

The three aspects of Quantization, programmers generally concerned with are:

• Coding error, Sampling rate and Amplification
• Sampling rate, Coding error and Conditioning
• Sampling rate, Aperture time and Coding error
• Aperture time, Coding error and Strobing

Question 19

The logic of pumping lemma is an example of __________.

• iteration

• recursion

• the divide and conquer principle

• the pigeon - hole principle

Question 20

Heap allocation is required for languages that

• use dynamic scope rules
• support dynamic data structures
• support recursion
• support recursion and dynamic data structures