Computer Science Study Materials for Competitive Exams

Sample Questions, Previous Year Solved Papers, Study Materials For Competitive Examinations Like UGC NET, SET And GATE Computer Science.

Friday, 30 September 2016

61.       Consider the following linear programming problem:
Max. z = 0.50x2 – 0.10x1
Subject to the constraints
2x1 + 5x2 ≤ 80
x1 + x2 ≤ 20
and x1, x2 ≥ 0
The total maximum profit (z) for the above problem is:
(A) 6       (B) 8
(C) 10     (D) 12
Answer: B
62.       Consider the following statements:
(a) If primal (dual) problem has a finite optimal solution, then its dual (primal) problem has a finite optimal solution.
(b) If primal (dual) problem has an unbounded optimum solution, then its dual (primal) has no feasible solution at all.
(c) Both primal and dual problems may be infeasible.
Which of the following is correct?
(A) (a) and (b) only      (B) (a) and (c) only
(C) (b) and (c) only      (D) (a), (b) and (c)
Answer: D
63.       Consider the following statements :
(a) Assignment problem can be used to minimize the cost.
(b) Assignment problem is a special case of transportation problem.
(c) Assignment problem requires that only one activity be assigned to each resource.
Which of the following options is correct?
(A) (a) and (b) only      (B) (a) and (c) only
(C) (b) and (c) only      (D) (a), (b) and (c)
Answer: D
64.       What are the following sequence of steps taken in designing a fuzzy logic machine ?
(A) Fuzzification → Rule evaluation → Defuzzification
(B) Fuzzification → Defuzzification → Rule evaluation
(C) Rule evaluation → Fuzzification → Defuzzification
(D) Rule evaluation → Defuzzification → Fuzzification
Answer: A
65.       Which of the following 2 input Boolean logic functions is linearly inseparable?
(a) AND                         (b) OR
(c) NOR             (d) XOR
(A) (a) and (b)               (B) (b) and (c)
(C) (c), (d) and (e)        (D) (d) and (e)
Answer: D

66.       Let R and S be two fuzzy relations defined as
Then, the resulting relation, T, which relates elements of universe of X to elements of universe of Z using max-product composition is given by
Answer: C
67.       Consider the following operations to be performed in Unix:
“The pipe sorts all files in the current directory modified in the month of “June” by order of size and prints them to the terminal screen. The sort option skips ten fields then sorts the lines in numeric order.”
Which of the following Unix command will perform above set of operations?
(A) ls – l | grep “June” | sort + 10n
(B) ls – l | grep “June” | sort + 10r
(C) ls – l | grep – v “June” | sort + 10n
(D) ls – l | grep – n “June” | sort + 10x
Answer: A
68.       Which of the following statements is incorrect for a Windows Multiple Document Interface (MDI)?
(A) Each document in an MDI application is displayed in a separate child window within the client area of the application’s main window.
(B) An MDI application has three kinds of windows namely a frame window, an MDI client window and number of child windows.
(C) An MDI application can support more than one kind of document.
(D) An MDI application displays output in the client area of the frame window.
Answer: D
69.       Which of the following statement(s) is/are True regarding ‘nice’ command of UNIX?
I. It is used to set or change the priority of a process.
II. A process’s nice value can be set at the time of creation.
III. ‘nice’ takes a command line as an argument.
(A) I, II only        (B) II, III only
(C) I, II, III           (D) I, III only
Answer: C
70.    Let v(x) mean x is a vegetarian, m(y) for y is meat, and e(x, y) for x eats y. Based on these, consider the following sentences:
I. x v(x) (y e(x, y) ¬m(y))
II. x v(x ) (¬(y m(y) ˄ e(x, y)))
III. x (y m(y) ˄ e(x, y)) ¬v(x)
One can determine that
(A) Only I and II are equivalent sentences
(B) Only II and III are equivalent sentences.
(C) Only I and III are equivalent sentence.
(D) I, II, and III are equivalent sentences.
Answer: D

Thursday, 29 September 2016

51.       An operating system supports a paged virtual memory, using a central processor with a cycle time of one microsecond. It costs an additional one microsecond to access a page other than the current one. Pages have 1000 words, and the paging device is a drum that rotates at 3000 revolutions per minute and transfers one million words per second. Further, one percent of all instructions executed accessed a page other than the current page. The instruction that accessed another page, 80% accessed a page already in memory and when a new page was required, the replaced page was modified 50% of the time. What is the effective access time on this system, assuming that the system is running only one process and the processor is idle during drum transfers ?
(A) 30 microseconds               (B) 34 microseconds
(C) 60 microseconds               (D) 68 microseconds
Answer: B
52.       Consider the following page reference string :
1, 2, 3, 4, 2, 1, 5, 6, 2, 1, 2, 3, 7, 6, 3, 2, 1, 2, 3, 6
Which of the following options, gives the correct number of page faults related to LRU, FIFO, and optimal page replacement algorithms respectively, assuming 05 page frames and all frames are initially empty ?
(A) 10, 14, 8      (B) 8, 10, 7
(C) 7, 10, 8        (D) 7, 10, 7
Answer: B
53.       Consider a file currently consisting of 50 blocks. Assume that the file control block and the index block is already in memory. If a block is added at the end (and the block information to be added is stored in memory), then how many disk I/O operations are required for indexed (single-level) allocation strategy ?
(A) 1       (B) 101
(C) 27     (D) 0
Answer: A
54.       An experimental file server is up 75% of the time and down for 25% of the time due to bugs. How many times does this file server have to be replicated to give an availability of at least 99% ?
(A) 2       (B) 4
(C) 8       (D) 16
Answer: B
55.       Given the following two languages:
L1 = {uwwRn | u, v, w ϵ {a, b}+}
L2 = {uwwRn | u, v, w ϵ {a, b}+, |u| ≥ |v|}
Which of the following is correct ?
(A) L1 is regular language and L2 is not regular language.
(B) L1 is not regular language and L2 is regular language.
(C) Both L1 and L2 are regular languages.
(D) Both L1 and L2 are not regular languages.
Answer: A

56.       Given a Turing Machine
M = ({q0, q1}, {0, 1}, {0, 1, B}, δ, B, {q1})
Where δ is a transition function defined as
δ (q0, 0) = (q0, 0, R)
δ (q0, B) = (q1, B, R)
The language L(M) accepted by Turing machine is given as :
(A) 0* 1*             (B) 00*
(C) 10*               (D) 1*0*
Answer: B
57.       Let G = (V, T, S, P) be a context-free grammar such that every one of its productions is of the form A → n, with |v| = k > 1. The derivation tree for any string W ϵ L (G) has a height such that
Answer: D
58.       Which of the following is not used in standard JPEG image compression?
(A) Huffman coding    (B) Runlength encoding
(C) Zig-zag scan          (D) K-L Transform
Answer: D
59.       Which of the following is a source coding technique?
(A) Huffman coding                (B) Arithmetic coding
(C) Run-length coding           (D) DPCM
Answer: D
60.    If the histogram of an image is clustered towards origin on X-axis of a histogram plot then it indicates that the image is .............
(A) Dark             (B) Good contrast
(C) Bright          (D) Very low contrast
Answer: A

Wednesday, 28 September 2016

41.       Which of the following tag in HTML is used to surround information, such as signature of the person who created the page ?
(A) <body> </body>                 (B) <address> </address>
(C) <strong> </strong>            (D) <em> </em>
Answer: B
42.       Java uses threads to enable the entire environment to be ................
(A) Symmetric               (B) Asymmetric
(C) Synchronous         (D) Asynchronous
Answer: D
43.       An Operating System (OS) crashes on the average once in 30 days, that is, the Mean Time Between Failures (MTBF) = 30 days. When this happens, it takes 10 minutes to recover the OS, that is, the Mean Time To Repair (MTTR) = 10 minutes. The availability of the OS with these reliability figures is approximately :
(A) 96.97%        (B) 97.97%
(C) 99.009%     (D) 99.97%
Answer: D
44.       Match each software lifecycle model in List – I to its description in List – II:
List – I                                       List – II
I. Code-and-Fix                        a. Assess risks at each step; do most critical
action first.
II. Evolutionary prototyping    b. Build an initial small requirement specifications,
code it, then “evolve” the specifications and code
as needed.
III. Spiral                                    c. Build initial requirement specification for
several releases, then design-and-code in
IV. Staged Delivery                 d. Standard phases (requirements, design,
code, test) in order
V. Waterfall                               e. Write some code, debug it, repeat
(i.e. ad-hoc)
Codes :
      I    II   III   IV   V
(A) e   b   a    c    d
(B) e   c   a    b    d
(C) d   a   b    c    e
(D) c   e   a    b    d
Answer: A
45.       Match each software term in List – I to its description in List – II:
List – I                                       List – II
I. Wizards                                  a. Forms that provide structure for a document
II. Templates                             b. A series of commands grouped into a
single command
III. Macro                                    c. A single program that incorporates most
commonly used tools
IV. Integrated Software           d. Step-by-step guides in application software
V. Software Suite                    e. Bundled group of software programs
Codes :
      I    II   III   IV   V
(A) d   a   b    c     e
(B) b   a   d    c     e
(C) d   e   b    a     c
(D) e   c   b    a     d
Answer: A

46.       The ISO quality assurance standard that applies to software Engineering is
(A) ISO 9000 : 2004     (B) ISO 9001 : 2000
(C) ISO 9002 : 2001    (D) ISO 9003 : 2004
Answer: B
47.       Which of the following are external qualities of a software product ?
(A) Maintainability, reusability, portability, efficiency, correctness.
(B) Correctness, reliability, robustness, efficiency, usability.
(C) Portability, interoperability, maintainability, reusability.
(D) Robustness, efficiency, reliability, maintainability, reusability.
Answer: B
48.       Which of the following is/are CORRECT statement(s) about version and release ?
I. A version is an instance of a system, which is functionally identical but nonfunctionally distinct from other instances of a system.
II. A version is an instance of a system, which is functionally distinct in some way from other system instances.
III. A release is an instance of a system, which is distributed to users outside of the development team.
IV. A release is an instance of a system, which is functionally identical but onfunctionally distinct from other instances of a system.
(A) I and III        (B) II and IV
(C) I and IV       (D) II and III
Answer: D
49.       The Unix Operating System Kernel maintains two key data structures related to processes, the process table and the user structure. Now, consider the following two statements:
I. The process table is resident all the time and contain information needed for all processes, even those that are not currently in memory.
II. The user structure is swapped or paged out when its associated process is not in memory, in order not to waste memory on information that is not needed.
Which of the following options is correct with reference to above statements ?
(A) Only (I) is correct.
(B) Only (II) is correct.
(C) Both (I) and (II) are correct.
(D) Both (I) and (II) are wrong.
Answer: C
50.    Consider a system which have ‘n’ number of processes and ‘m’ number of resource types. The time complexity of the safety algorithm, which checks whether a system is in safe state or not, is of the order of:
(A) O(mn)          (B) O(m2n2)
(C) O(m2n)        (D) O(mn2)
Answer: D