ISRO Scientist/Engineer SC Computer Science 2015 — ISRO Scientist/Engineer SC 2015 · Computer Science

Which of the given number has its IEEE-754 32 bit floating point representation as 0 10000000 110 0000 0000 0000 0000 0000

The range of integers that can be represented by an n-bit 2’s complement number system is

How many 32K × 1 RAM chips are needed to provide a memory capacity of 256 Kbytes?

A modulus -12 ring counter requires a minimum of

The complement of the Boolean expression AB ( B'C + AC ) is , ISRO 2015

The code which uses 7 bits to represent a character is

If half adders and full adders are implements using gates, then for the addition of two 17 bit numbers (using minimum gates) the number of half adders and full adders required will be

Minimum number of 2 × 1 multiplexers required to realize the following function,

f = A'B'C + A'B'C'

Assume that inputs are available only in true form and Boolean a constant 1 and 0 are available.

The number of 1’s in the binary representation of (3 × 4096 + 15 × 256 + 5 × 16 + 3) is:

The boolean expression AB + AB'+ A'C + AC is independent of the boolean variable

If the sequence of operations - push (1), push (2), pop, push (1), push (2), pop, pop, pop, push (2), pop are performed on a stack, the sequence of popped out values

A machine needs a minimum of 100 sec to sort 1000 names by quick sort. The minimum time needed to sort 100 names will be approximately

Six files F1, F2, F3, F4, F5 and F6 have 100, 200, 50, 80, 120, 150 records respectively. In what order should they be stored so as to optimize act. Assume each file is accessed with the same frequency

A hash table with 10 buckets with one slot per bucket is depicted here. The symbols, S1 to S7 are initially entered using a hashing function with linear probing. The maximum number of comparisons needed in searching an item that is not present is

The queue data structure is to be realized by using stack. The number of stacks needed would be

Consider the following Entity Relationship Diagram (ERD)

Which of the following possible relations will not hold if the above ERD is mapped into a relation model?

Consider the following log sequence of two transactions on a bank account, with initial balance 12000, that transfer 2000 to a mortgage payment and then apply a 5% interest.

  1. T1 start
  2. T1 B old=12000 new=10000
  3. T1 M old=0 new=2000
  4. T1 commit
  5. T2 start
  6. T2 B old=10000 new=10500
  7. T2 commit 

Suppose the database system crashes just before log record 7 is written. When the system is restarted, which one statement is true of the recovery procedure?

Given a block can hold either 3 records or 10 key pointers. A database contains n records, then how many blocks do we need to hold the data file and the dense index

The maximum length of an attribute of type text is

Let R ={A, B, C, D, E, F} be a relation schema with the following dependencies C → F, E → A, EC → D, A → B Which of the following is a key for R ?

If D1, D2...Dn are domains in a relational model, then the relation is a table, which is a subset of

Consider the following relational query on the above database:

SELECT S.sname
    FROM Suppliers S
        WHERE S.sid NOT IN (SELECT C.sid
                            FROM Catalog C
                            WHERE C.pid NOT IN (SELECT P.pid  
                                                FROM Parts P
                                                WHERE P.color<> 'blue'))

Assume that relations corresponding to the above schema are not empty. Which one of the following is the correct interpretation of the above query?

Consider the following schema:

Emp (Empcode, Name, Sex, Salary, Deptt)

A simple SQL query is executed as follows:

SELECT Deptt FROM Emp
WHERE sex = 'M'
GROUP by Dept
Having avg (Salary) > {select avg (Salary) from Emp}

The output will be

Given the following expression grammar:

E → E ∗ F ∣ F + E ∣ F
F → F − F ∣ id

Which of the following is true? ISRO 2015

The number of token the following C statement is printf("i = %d, &i =%x", i,&i);

Which grammar rules violate the requirement of the operator grammar? A, B, C are variables and a, b, c are terminals.

i. A → BC
ii. A → CcBb
iii. A → BaC
iv. A → ε

Which one of the following is a top-down parser?

Yacc stands for

Which statement is true?

Which choice gives the complete set of problems that semaphores can solve?

I. Race condition

II. Process synchronization

III. Mutual exclusion

If there are 32 segments, each size 1 k bytes, then the logical address should have

In a lottery scheduler with 40 tickets, how we will distribute the tickets among 4 processes and such that each process gets 10%, 5%, 60% and 25% respectively?

     P1   P2   P3   P4
a)   12   4    70   30
b)   7    5    20   10
c)   4    2    24   10
d)   8    5    40   30

Suppose a system contains n processes and system uses the round-robin algorithm for CPU scheduling then which data structure is best suited for ready queue of the process

A hard disk system has the following parameters: Number of tracks = 500; Number of sectors/track = 100; Number of bytes/sector = 500; Time taken by the head to move from one track to adjacent track = 1 ms; Rotation speed = 600 rpm. What is the average time taken for transferring 250 bytes from the disk? Assume the conventional average seek distance is half of 500 tracks (250 tracks).

At a particular time of computation the value of a counting semaphore is 7. Then 20 P operations and 15 V operations were completed on this semaphore. The resulting value of the semaphore is :

Increasing the RAM of a computer typically improves performance because:

Consider the following program. main() { fork(); fork(); fork(); } How many new processes will be created?

Suppose two jobs, each of which needs 10 min of CPU time, start simultaneously. Assume 50% I/O wait time. How long will it take for both to complete if they run sequentially?

If a node has K children in Btree, then the node contains exactly _____ keys.

The time complexity of the following C function is (assume n > 0)

int recursive (int n) {
     if(n == 1)
     return (1);
     else
     return (recursive (n-1) + recursive (n-1));
}

The number of spanning trees for a complete graph with seven vertices is

If one uses straight two-way merge sort algorithm to sort the following elements in ascending order: 20, 47, 15, 8, 9, 4, 40, 30, 12, 17 then the order of these elements after second pass of the algorithm is:

Let R1 and R2 be regular sets defined over the alphabet, then

The DNS maps the IP addresses to

To add a background color for all <h1> elements, which of the following HTML syntax is used

The correct syntax to write “Hi There” in Javascript is

To declare the version of XML, the correct syntax is

A T-switch is used to

What frequency range is used for microwave communications, satellite and radar?

How many bits internet address is assigned to each host on a TCP/IP internet which is used in all communication with the host?

How many characters per sec (7 bits + 1 parity) can be transmitted over a 2400 bps line if the transfer is asynchronous (1 start and 1 stop bit)?

In CRC if the data unit is 100111001 and the divisor is 1011 then what is dividend at the receiver?

In TCP, an ACK number of 1000 always means that ______.

In a class B subnet, we know the IP address of one host and the mask as given below :

IP address = 125.134.112.66
Mask = 255.255.224.0

What is the first address (Network address)?

A certain population of ALOHA users manages to generate 70 request/sec. If the time is slotted in units of 50 msec, then channel load would be

Which statement is false?

A router uses the following routing table:

A packet bearing a destination address 144.16.68.117 arrives at the router. On which interface will it be forwarded?

Which layers of the OSI reference model are host-to-host layers?

Alpha and Beta testing are forms of

If in a software project the number of user input, user output, enquiries, files and external interfaces are (15, 50, 24, 12, 8), respectively, with complexity average weighing factor. The productivity if effort = 70 person-month is

The contents of the flag register after execution of the following program by 8085 microprocessor will be

Program
SUB A
MVI B,(01)H
DCR B
HLT

The minimum time delay between the initiation of two independent memory operations is called

Which of the following compression algorithms is used to generate a .png file?

Dirty bit for a page in a page table

Which of the following is not an image type used in MPEG?

Consider an uncompressed stereo audio signal of CD quality which is sampled at 44.1 kHz and quantized using 16 bits. What is required storage space if a compression ratio of 0.5 is achieved for 10 seconds of this audio?

Compared with uncompressed CD-quality PCM, what is the conventionally cited approximate compression ratio for a typical 128 kbps MP3 audio file?

Consider the following program fragment

if(a > b)
if(b > c)
s1;
else s2;

s2 will be executed if

If n has 3, then the statement a[++n]=n++;

The following program main() { inc(); inc(); inc(); } inc() { static int x; printf("%d", ++x); }

Consider the following program fragment i=6720; j=4; while (i%j)==0 { i=i/j; j=j+1; } On termination j will have the value

Consider the following declaration:

int a, *b=&a, **c=&b;

The following program fragment

a=4;
**c=5;

The output of the following program is

main()
{
static int x[] = {1,2,3,4,5,6,7,8};
int i;
for (i=2; i<6; ++i)
x[x[i]]=x[i];
for (i=0; i<8; ++i)
printf("%d", x[i]);
} 

The for loop

for (i=0; i<10; ++i)
printf("%d", i&1);

prints:

In X = (M + N x O)/(P x Q), how many one-address instructions are required to evaluate it?

The decimal number has 64 digits.The number of bits needed for its equivalent binary representation is?

Consider the following C declaration 

struct 
{
    short s[5];
    union 
    {
        float y;
        long z;
    }
    u;
}t;

Assume that objects of type short, float and long occupy 2 bytes, 4 bytes and 8 bytes, respectively. The memory requirement for variable t, ignoring alignment considerations, is

Consider the following code fragment
void foo(int x, int y)
{
x+=y;
y+=x;
}
main()
{
int x=5.5;
foo(x,x);
}
What is the final value of x in both call by value and call by reference, respectively?