UGC NET CS 2014 Dec - III

Question 1

A hierarchical memory system that uses cache memory has cache access time of 50 nano seconds, main memory access time of 300 nano seconds, 75% of memory requests are for read, hit ratio of 0.8 for read access and the write-through scheme is used. What will be the average access time of the system both for read and write requests ?

• 157.5 n.sec.
• 110 n.sec.
• 75 n.sec.
• 82.5 n.sec.

Question 2

For switching from a CPU user mode to the supervisor mode following type of interrupt is most appropriate

• Internal interrupts
• External interrupts
• Software interrupts
• None of the above

Question 3

In a dot matrix printer the time to print a character is 6 m.sec., time to space in between characters is 2 m.sec., and the number of characters in a line are 200. The printing speed of the dot matrix printer in characters per second and the time to print a character line are given by which of the following options?

• 125 chars/second and 0.8 seconds
• 250 chars/second and 0.6 seconds
• 166 chars/second and 0.8 seconds
• 250 chars/second and 0.4 seconds
• 125 chars/second and 1.6 seconds

Question 4

Match the following:

List - I	List - II
(a)XCHG	(i)only carry flag is affected.
(b)SUB	(ii) no flags are affected.
(c)STC	(iii) all flags other than carry flag are affected.
(d)DCR	(iv)all flags are affected.

codes:

	(a)	(b)	(c)	(d)
(1)	(iv)	(i)	(iii)	(ii)
(B)	(iii)	(ii)	(i)	(iv)
(C)	(ii)	(iii)	(i)	(iv)
(D)	(ii)	(iv)	(i)	(iii)

• (A)
• (B)
• (C)
• (D)

Question 5

How many times will the following loop be executed?  LXI B, 0007 H LOP : DCX B   MOV A, B   ORA C   JNZ LOP

• 05
• 07
• 09
• 00

Question 6

Specify the contents of the accumulator and the status of the S, Z and CY flags when 8085 microprocessor performs addition of 87 H and 79 H.

• 11, 1, 1, 1
• 10, 0, 1, 0
• 1, 1, 0, 0
• 00, 0, 1, 1

Question 7

Location transparency allows: I.Users to treat the data as if it is done at one location. II. Programmers to treat the data as if it is at one location. III. Managers to treat the data as if it is at one location. Which one of the following is correct?

• I, II and III
• I and II only
• II and III only
• II only

Question 8

Which of the following is correct ? I.Two phase locking is an optimistic protocol. II. Two phase locking is pessimistic protocol III. Time stamping is an optimistic protocol. IV. Time stamping is pessimistic protocol.

• I and III
• II and IV
• I and IV
• II and III

Question 9

Consider the following statements: I.Re-construction operation used in mixed fragmentation satisfies commutative rule. II. Re-construction operation used in vertical fragmentation satisfies commutative rule Which of the following is correct?

• I
• II
• Both are correct
• None of the statements are correct.

Question 10

Which of the following is false?

• Every binary relation is never be in BCNF.
• Every BCNF relation is in 3NF.
• 1 NF, 2 NF, 3 NF and BCNF are based on functional dependencies.
• Multivalued Dependency (MVD) is a special case of Join Dependency (JD).