## UGC Net Computer Science December-12 Paper 3 (Solved)

1. Eco system is a Frame work for

(A) Building a Computer System

(B) Building Internet Market

(C) Building Offline Market

(D) Building Market

__Answer B__

*Explanation :*
A digital ecosystem is a distributed, adaptive, open socio-technical system with properties of self-organisation, scalability and sustainability inspired from natural ecosystems. Digital ecosystem models are informed by knowledge of natural ecosystems, especially for aspects related to competition and collaboration among diverse entities. The term is used in the computer industry, the entertainment industry, and the World Economic Forum.

An ecosystem includes all of the living things (plants, animals and organisms) in a given area, interacting with each other, and also with their non-living environments (weather, earth, sun, soil, climate, atmosphere).

So as mentioned its proves that eco system increase interaction between living and non living things in same way internet play this type of role.

2. The efficiency (E) and speed up (sp) for Multiprocessor with p processors satisfies :

(A) E <= p and Sp <= p

(B) E <=1 and Sp <= p

(C) E <= p and Sp <= 1

(D) E <= 1 and Sp <= 1

2. The efficiency (E) and speed up (sp) for Multiprocessor with p processors satisfies :

(A) E <= p and Sp <= p

(B) E <=1 and Sp <= p

(C) E <= p and Sp <= 1

(D) E <= 1 and Sp <= 1

__Answer B__**3. Match the following :**

List – I List – II

a. Critical region 1. Hoares Monitor

b. Wait/signal 2. Mutual exclusion

c. Working set 3. Principal of locality

d. Dead lock 4. Circular wait

Codes :

a b c d

(A) 2 1 3 4

(B) 1 2 4 3

(C) 2 3 1 4

(D) 1 3 2 4

4. The technique of temporarily delaying outgoing acknowledgements so that they can be hooked onto the next outgoing data frame is known as

(A) Bit stuffing

(B) Piggy backing

(C) Pipelining

(D) Broadcasting

5. ______ is process of extracting previously non known valid and actionable information from large data to make crucial business and strategic

decisions.

(A) Data Management

(B) Data base

(C) Data Mining

(D) Meta Data

6. The aspect ratio of an image is defined as

(A) The ratio of width to its height measured in unit length.

(B) The ratio of height to width measured in number of pixels.

(C) The ratio of depth to width measured in unit length.

(D) The ratio of width to depth measured in number of pixels.

Multiprogramming is a rudimentary form of parallel processing in which several programs are run at the same time on a uniprocessor. Since there is only one processor, there can be no true simultaneous execution of different programs. Instead, the operating system executes part of one program, then part of another, and so on. To the user it appears that all programs are executing at the same time. By this definition we can say that all given option is valid for multiprogrammed system.

8. Using RSA algorithm, what is the value of cipher text C, if the plain text M = 5 and p = 3, q = 11 & d = 7 ?

(A) 33

(B) 5

(C) 25

(D) 26

Given p=3,q=11. n=(p X q) = (3 X 11)=33

m=(p-1)X(q-1) = (2 X 10)=20

Find a small odd integer e, that is relatively prime to m.

If e=3, then GCD(3,20)=1. e should be small and prime and so we let e=3.

d is given, d=7.

Public key = (e,n). (Values of e and n are known).

To encrypt a message, we apply the public key to the function

E(s) = se(mod n),

where s is the given message and e and n represent the public key integer pair. In the above question, the plain text M = 5. Plain text needs to be encrypted using the above formula.

E(s) = se(mod n)

=53(mod 33)

= 125 (mod 33)

= 26

9. You are given an OR problem and a XOR problem to solve. Then, which one of the following statements is true ?

(A) Both OR and XOR problems can be solved using single layer perception.

(B) OR problem can be solved using single layer perception and XOR problem can be solved using self organizing maps.

(C) OR problem can be solved using radial basis function and XOR problem can be solved using

single layer perception.

(D) OR problem can be solved using single layer perception and XOR problem can be solved using

radial basis function.

List – I List – II

a. Application layer 1. TCP

b. Transport layer 2. HDLC

c. Network layer 3. HTTP

d. Data link layer 4. BGP

a b c d

(A) 2 1 4 3

(B) 3 4 1 2

(C) 3 1 4 2

(D) 2 4 1 3

a. Critical region 1. Hoares Monitor

b. Wait/signal 2. Mutual exclusion

c. Working set 3. Principal of locality

d. Dead lock 4. Circular wait

Codes :

a b c d

(A) 2 1 3 4

(B) 1 2 4 3

(C) 2 3 1 4

(D) 1 3 2 4

__Answer A__

(A) Bit stuffing

(B) Piggy backing

(C) Pipelining

(D) Broadcasting

__Answer B__*Explanation :*
In two-way communication, whenever a data frame is received, the receiver waits and does not send the control frame (acknowledgement or ACK) back to the sender immediately.

The receiver waits until its network layer passes in the next data packet. The delayed acknowledgement is then attached to this outgoing data frame.

This technique of temporarily delaying the acknowledgement so that it can be hooked with next outgoing data frame is known as piggybacking.5. ______ is process of extracting previously non known valid and actionable information from large data to make crucial business and strategic

decisions.

(A) Data Management

(B) Data base

(C) Data Mining

(D) Meta Data

__Answer C__**data mining (sometimes called data or knowledge discovery) is the process of analyzing data from different perspectives and summarizing it into useful information - information that can be used to increase revenue, cuts costs, or both. Data mining software is one of a number of analytical tools for analyzing data. It allows users to analyze data from many different dimensions or angles, categorize it, and summarize the relationships identified. Technically, data mining is the process of finding correlations or patterns among dozens of fields in large relational databases.**

*Explanation :*(A) The ratio of width to its height measured in unit length.

(B) The ratio of height to width measured in number of pixels.

(C) The ratio of depth to width measured in unit length.

(D) The ratio of width to depth measured in number of pixels.

__Answer A__*Explanation :*
The aspect ratio of an image describes the proportional relationship between its width and its height. It is commonly expressed as two numbers separated by a colon, as in 16:9. For an x:y aspect ratio, no matter how big or small the image is, if the width is divided into x units of equal length and the height is measured using this same length unit, the height will be measured to be y units.

7. Which of the following features will characterize an OS as multiprogrammed OS ?

(a) More than one program may be loaded into main memory at the same time.

(b) If a program waits for certain event another program is immediately scheduled.

(c) If the execution of a program terminates, another program is immediately scheduled.

(A) (a) only

(B) (a) and (b) only

(C) (a) and (c) only

(D) (a), (b) and (c) only

__Answer D__*Explanation :*Multiprogramming is a rudimentary form of parallel processing in which several programs are run at the same time on a uniprocessor. Since there is only one processor, there can be no true simultaneous execution of different programs. Instead, the operating system executes part of one program, then part of another, and so on. To the user it appears that all programs are executing at the same time. By this definition we can say that all given option is valid for multiprogrammed system.

8. Using RSA algorithm, what is the value of cipher text C, if the plain text M = 5 and p = 3, q = 11 & d = 7 ?

(A) 33

(B) 5

(C) 25

(D) 26

__Answer D__*Explanation :*Given p=3,q=11. n=(p X q) = (3 X 11)=33

m=(p-1)X(q-1) = (2 X 10)=20

Find a small odd integer e, that is relatively prime to m.

If e=3, then GCD(3,20)=1. e should be small and prime and so we let e=3.

d is given, d=7.

Public key = (e,n). (Values of e and n are known).

To encrypt a message, we apply the public key to the function

E(s) = se(mod n),

where s is the given message and e and n represent the public key integer pair. In the above question, the plain text M = 5. Plain text needs to be encrypted using the above formula.

E(s) = se(mod n)

=53(mod 33)

= 125 (mod 33)

= 26

9. You are given an OR problem and a XOR problem to solve. Then, which one of the following statements is true ?

(A) Both OR and XOR problems can be solved using single layer perception.

(B) OR problem can be solved using single layer perception and XOR problem can be solved using self organizing maps.

(C) OR problem can be solved using radial basis function and XOR problem can be solved using

single layer perception.

(D) OR problem can be solved using single layer perception and XOR problem can be solved using

radial basis function.

__Answer D__**10. Match the following :**

List – I List – II

a. Application layer 1. TCP

b. Transport layer 2. HDLC

c. Network layer 3. HTTP

d. Data link layer 4. BGP

**Codes :**a b c d

(A) 2 1 4 3

(B) 3 4 1 2

(C) 3 1 4 2

(D) 2 4 1 3

__Answer C__