UGC NET Paper 2 Computer Science – June 2019 – Question Paper with Answer Key

Consider the poset ({3, 5, 9, 15, 24, 45}, |) under divisibility. Which of the following is correct?

How many ways are there to place 8 indistinguishable balls into four distinguishable bins?

How many bit strings of length ten either start with a 1 bit or end with two bits 00 ?

Suppose that a connected planar graph has six vertices, each of degree four. Into how many regions is the plane divided by a planar representation of this graph?

For which values of and does the complete k bipartite graph m,n have a Hamilton circuit?

Which of the following is the principal conjunctive normal form of [(p ∨ q) ∧ ¬p] → ¬q?

How many cards must be selected from a standard deck of 52 cards to guarantee that at least three hearts are present among them?

Match List I with List II. List I: (a) p → q, (b) p ∨ q, (c) p ∧ q, (d) ¬(p → q). List II: (i) ¬(q → ¬p), (ii) p ∧ ¬q, (iii) ¬p → q, (iv) ¬p ∨ q.

Find the zero-one matrix of the transitive closure of the relation with matrix A = [1 0 1; 0 1 0; 1 1 0].

For the LPP: maximize Z = 2x₁ − x₂ + 2x₃ subject to 2x₁ + x₂ ≤ 10, x₁ + 2x₂ − 2x₃ ≤ 20, x₁ + 2x₃ ≤ 5, x₁, x₂, x₃ ≥ 0, what is the solution after the first simplex iteration?

Which type of addressing mode, less number of memory references are required?

Suppose that the register and the register have the bit configuration. Only the three A leftmost bits of are compared with memory K words because has l's in these positions. Because of its organization, this type of memory is uniquely suited to parallel searches by data association. This type of memory is known as

How many different Boolean functions of degree n are there?

The fault can be easily diagnosed in the micro- program control unit using diagnostic tools by maintaining the contents of

What will be the number of states when a MOD- 2 counter is followed by a MOD- 5 counter?

For a magnetic disk with concentric circular tracks, the seek latency is not linearly proportional to the seek distance due to

The parallel bus arbitration technique uses an external priority encoder and a decoder. Suppose, a parallel arbiter has 5 bus arbiters. What will be the size of the priority encoder and decoder respectively?

Consider (146)_b + (313)_(b−2) = (246)_8. What is b?

How many address lines and data lines are required to provide a memory capacity of 16 K × 16 ?

Suppose that a computer program takes 100 seconds of execution time on a computer with multiplication operation responsible for 80 seconds of this time. How much do you have to improve the speed of multiplication operation if you are asked to execute this program four times faster?

With preconditions p ≥ 1 and n ≥ 0 (no overflow): int x = p; int k = n; int m = 1; while (k != 0) { if (k is odd) m = m * x; x = x * x; k = floor(k / 2); } The loop invariant is m·xᵏ = pⁿ and k ≥ 0. Which must be true at the end?

On a 32-bit x86 machine: typedef struct { union { unsigned char a; unsigned short b; } U; unsigned char c; } S; S B[10]; S *p = &B[4]; S *q = &B[5]; p->U.b = 0x1234; (S takes 32 bits). If M is q − p and N is (int)&(p->c) − (int)p, then (M, N) is

Class Good has a field m and a method public boolean equals(Good n) { return n.m == m; }. In main: Good m1 = new Good(22), m2 = new Good(22); Object s1 = new Good(22), s2 = new Good(22); then it prints m1.equals(m2), s1.equals(s2), m1.equals(s2), s1.equals(m2). What is printed?

Consider the following function ) : f n unsigned int (unsigned int )( b = 0

unsigned int ;
while (n) {
b+ = n&1
;
n ≫>= 1
;
}
return b;}
```
f (

The function ) returns the int that represents _P_ the in the binary representation of positive n P

integer , where is

Which of the following statements is/are true? P : In a scripting language like JavaScript, types are typically associated with values, not variables. Q : It is not possible to show images on a web page without the <img> tag of HTML. Select the correct answer from the options given below :

Which of the following statements is/are true? P : An XML document with correct syntax as specified by W3C is called "Well Formed". Q : An XML documented validated against a DTD is both "Well formed" and "Valid". R : <xml version="1.0" encoding="UTF-8"> is syntactly correct declaration for the version of an XML document. Select the correct answer from the options given below : P Q

Consider a raster system with resolution 640 by 480 . What size is frame buffer (in bytes) for this system to store 12 bits per pixel?

Consider the following statements regarding 2D transforms in computer graphics: 1 0 [ ] 2 × 2

S1 : is a matrix that reflects 0 −1 2D X (mirrors) only point about the -axis. 2 × 2 2D

S2 : A matrix which mirrors any point X about the -axis, is a rotation matrix. What can you say about the statements S1 and S2?

In the context of 3D computer graphics, which of the following statements is/are true? P : Orthographic transformations keep parallel lines parallel. Q : Orthographic transformations are affine transformations. Select the correct answer from the options given below :

Using the phong reflectance model, the strength of the specular highlight is determined by the angle between

Which of the following has same expressive power with regard to relational query language?

(a) Relational algebra and domain relational calculus

(b) Relational algebra and tuples relational calculus

(c) Relational algebra and domain relational calculus restricted to safe expression

(d) Relational algebra and tuples relational calculus restricted to safe expression

Which of the following features is supported in the relational database model?

With respect to relational algebra, which of the following operations are included for mathematical set theory?

(a) Join

(b) Intersection

(c) Cartisian product

(d) Project

In relational databases, if relation is in , then which of the following is true about relation R ?

Which of the following key constraints is required for functioning of foreign key in the context of relational databases?

In relational database management, which of the following is/are property/properties of candidate key? P : Uniqueness Q : Irreducibility

Which of the following statements are DML statements?

(a) Update [tablename] = Set [ columnname] VALUE

(b) Delete [tablename]

(c) Select * from [tablename]

Hadoop (a big data tool) works with number of related tools. Choose from the following, the common tools included into Hadoop :

A table has attributes Employee_id (primary key) and Manager_id (foreign key referencing Employee_id with ON DELETE CASCADE), with tuples (20, 40), (25, 40), (30, 35), (35, 20), (40, 45), (45, 25). On deleting the tuple (20, 40), which other tuples must be deleted to maintain referential integrity?

-mean clustering algorithm has clustered the 1st given 8 observations into 3 clusters after iteration as follows:

C1 : {(3, 3), (5, 5), (7, 7)}
C2 : {(0, 6), (6, 0), (3, 0)}
C3 : {(8, 8), (4, 4)}

What will be the Manhattan distance for (4, 4) C1 observation from cluster centroid in second iteration? –

Consider a disk system with 100 cylinders. The requests to access the cylinders occur in the following sequence : 4, 34, 10, 7, 19, 73, 2, 15, 6, 20 Assuming that the head is currently at cylinder 50 , what is the time taken to satisfy all requests 1 ms if it takes to move from the cylinder to adjacent one and the shortest seek time first policy is used?

Match List I with List II. List I: (a) Disk, (b) CPU, (c) Memory, (d) Interrupt. List II: (i) Thread, (ii) Signal, (iii) File system, (iv) Virtual address space.

Which of the following are NOT shared by the threads of the same process?

(a) Stack

(b) Registers

(c) Address space

(d) Message queue

Consider that a process has been allocated 3 frames and has a sequence of page referencing 1, 2, 1, 3, 7, 4, 5, 6, 3, 1 as . What shall be the difference in page faults for the above string using the algorithms of LRU and optimal page replacement for referencing the string?

Consider three CPU intensive processes, which require 10,20 and 30 units of time and arrive at times 0,2 and 6 respectively. How many context switches are needed if the operating system implements a shortest remaining time first scheduling algorithm? Do not count the context switches at time zero and at the end.

At a particular time of computation, the value of a counting semaphore is 7. Then 20 P (wait) operations and 15 V (signal) operations are completed on this semaphore. What is the resulting value of the semaphore?

The minimum number of page frames that must be allocated to a running process in a virtual memory environment is determined by

A computer has six tape drives with (n) processes competing for them. Each process may need two drives. What is the maximum value of (n) for the system to be deadlock free?

A processor can support a maximum memory of (4 GB) where memory is word addressable and a word is 2 bytes. What will be the size of the address bus of the processor?

Which of the following UNIX/Linux pipes will ⋅c count the number of lines in all the files having h and as their extension in the current working directory?

The M components in MVC are responsible for

Software reuse is

Which of the following terms best describes Git?

A Web application and its support environment has not been fully fortified against attack. Web engineers estimate that the likelihood of repelling an attack is only 30 percent. The application does not contain sensitive or controversial information, so the threat probability is 25 percent. What is the integrity of the web application?

Match List I (process models) with List II (systems). List I: (a) Waterfall model, (b) Incremental development, (c) Prototyping, (d) RAD. List II: (i) e-business software that starts with basic functionality and then moves to advanced features, (ii) An inventory control system for a supermarket to be developed within three months, (iii) A virtual reality system for simulating vehicle navigation on a highway, (iv) Automating the manual student record system of a school.

Which of the following are the primary objectives of risk monitoring in software project tracking? P : To assess whether predicted risks do, in fact, occur Q : To ensure that risk aversion steps defined for the risk are being properly applied R : To collect information that can be used for future risk analysis

Software validation mainly checks for inconsistencies between

Match List I with List II. List I: (a) Prim's algorithm, (b) Dijkstra's algorithm, (c) Faster all-pairs shortest path, (d) Edmonds-Karp algorithm. List II: (i) O(V³ lg V), (ii) O(VE²), (iii) O(E lg V), (iv) O(V²).

There are many sorting algorithms based on comparison. The running time of heapsort O(n lg n) P Q algorithm is . Like , but unlike , (P, Q) heapsort sorts in place where is equal to

Consider the Euler's phi function given by ϕ(n) = n ∏ (1 − 1 ) p p n where runs over all the primes dividing . What ϕ(45) is the value of ?

Which of the following is best running time to n n2 − 1 sort integers in the range 0 to ?

Which of the following is application of depth- first search?

Consider double hashing of the form h(k, i) = (h (k) + ih (k)) mod m 1 2 h (k) = k mod m where 1 h (k) = 1 + (k mod n) 2 n = m − 1 m = 701 where and k = 123456 For , what is the difference between first and second probes in terms of slots?

Consider the complexity class as the ¯¯¯ L ∈ NP set of languages L such that , and the following two statements :

S : P ⊆ CO − NP 1 S NP ≠ CO − NP P ≠ NP

2 : If , then Which of the following is/are correct? S

Consider the following steps : S

1 : Characterize the structure of an optimal solution S

2 : Compute the value of an optimal solution in bottom-up fashion Which of the step(s) is/are common to both dynamic programming and greedy algorithms? S

Consider the following properties with respect to G = (V , E) a flow network in which a flow is a f : V × V → R real-valued function : P : For all u, v ∈ V , f(u, v) = −f(v, u) 1 P : ∑ f(u, v) = 0 for all u ∈ V 2 v∈V Which one of the following is/are correct? P

Consider the following statements : S n > 1, aϕ(n) ≡ 1(mod n)

1 : For any integer a ∈ Z∗ ϕ(n) for all n , where is Euler's phi function. S p ap ≡ 1(mod p)

2 : If is prime, then for all a ∈ Z∗ p . Which one of the following is/are correct? S

Which data structure is used by the compiler for managing variables and their attributes?

On translating the expression given below into quadruple representation, how many operations are required? (i*j)+(e+f)*(a*b+c)

Replacing the expression by 8.56 is known as

Shift-reduce parser consists of

(a) input buffer

(b) stack

(c) parse table

How many states are there in a minimum state automata equivalent to regular expression given below? a * b(a + b) Regular expression is

Match List I with List II, where L1 is regular, L2 context-free, L3 recursive and L4 recursively enumerable. List I: (a) complement(L3) ∪ L4, (b) complement(L2) ∪ L3, (c) L1* ∩ L2. List II: (i) Context-free language, (ii) Recursively enumerable language, (iii) Recursive language.

How can the decision algorithm be constructed L for deciding whether context-free language is finite? CFGG

(a) By constructing redundant in CNF L generating language −−

(b) By constructing non-redundant CFG G in CNF L generating language CFGG

(c) By constructing non-redundant in CNF L − {∧}(∧ generating language stands for null) Which of the following is correct?

Consider the following grammar :

S → XY

X → Y aY ∣ a and Y → bbX Which of the following statements is/are true about the above grammar?

(a) Strings produced by the grammar can have a consecutive three 's.

(b) Every string produced by the grammar have a b alternate and .

(c) Every string produced by the grammar have a at least two 's. b

(d) Every string produced by the grammar have 's in multiple of 2.

Which of the following problems is/are decidable problem(s) (recursively enumerable) on turing M machine ? G L(G) = ϕ

(a) is a CFG with M M

(b) There exist two TMs 1 and 2 such that L(M) ⊆ {L (M ) ∪ L (M )} = 1 2 language of TMs all ω 2|ω|

(c) M is a TM that accepts using at most cells of tape

For a statement L ⊆ Σ∗ A language is recursive if there exists M some turing machine . Which of the following conditions is satisfied for ω any string ? ω ∈ L M ω M

A fully connected network topology is a topology in which there is a direct link between all pairs of nodes. Given a fully connected n network with nodes, the number of direct links n as a function of can be expressed as

What is the name of the protocol that allows a client to send a broadcast message with its MAC address and receive an IP address in reply?

You are designing a link layer protocol for a link with a bandwidth of 1 Gbps (109bits/second) over a fiber link with a length of 800 km. Assume the speed of light in this medium is 200000 km/second. What is the propagation delay in this link?

You need 500 subnets, each with about 100 usable host addresses per subnet. What network mask will you assign using a class B network address?

Consider the following two statements with respect to IPv4 in computer networking : P: The loopback (IP) address is a member of the class B network. Q: The loopback (IP) address is used to send a packet from the host to itself. What can you say about the statements P and Q?

In the TCP/IP model, encryption and decryption are functions of the ____ layer.

Which of the following statements is/are true with regard to various layers in the Internet stack? P: At the link layer, a packet of transmitted information is called a frame. Q: At the network layer, a packet of transmitted information is called a segment.

What percentage % of the IPv4, IP address space do all class C addresses consume?

The ability to inject packets into the Internet with a false source address is known as

The RSA encryption algorithm also works in reverse, that is, you can encrypt a message with the private key and decrypt it using the public key. This property is used in

Consider the game tree given below :

Here and represents MIN and MAX nodes respectively. The value of the root node of the game tree is

Match List I with List II. List I: (a) Greedy best-first, (b) Lowest cost-first, (c) A* algorithm. List II: (i) Minimal cost(p) + h(p), (ii) Minimal h(p), (iii) Minimal cost(p).

The STRIPS representation is

A fuzzy conjunction operator denoted as t(x,y) and a fuzzy disjunction operator denoted as s(x,y) form a dual pair if they satisfy the condition :

Let α denotes the -cut of a fuzzy set A at 0 α α α 0 . If 1 < 2 , then

Consider the following methods : M1: Mean of maximum M2: Centre of area M3: Height method Which of the following is/are defuzzification method(s)?

Consider the following :

(a) Evolution

(b) Selection

(c) Reproduction

(d) Mutation Which of the following are found in genetic algorithms?

Which of the following is an example of unsupervised neural network?

The value of the derivative of the Sigmoid function given by f(x) = 1 1+e−2x at x=0 is

Reinforcement learning can be formalized in terms of _____ in which the agent initially only knows the set of possible ____ and the set of possible actions.