Sub-AME at Department of Immigration & Passport-2014

Sub-AME at Department of Immigration & Passport-2014

Q-1. Describe the main properties of OOP ?

 Ans:Fundamental principles of OOP:

•   Inheritance- Inheritance is the mechanism of basing an object or class upon another object (prototypical inheritance) or class (class-based inheritance), retaining similar implementation.

•   Polymorphism- Polymorphism is the provision of a single interface to entities of different types or the use of a single symbol to represent multiple different types.

•   Abstraction- Abstraction is a process of hiding the implementation details from the user, only the functionality will be provided to the user. In other words, the user will have the information on what the object does instead of how it does it.

•   Encapsulation- Encapsulation is an OOP concept that binds together the data and functions that manipulate the data, and that keeps both safe from outside interference and misuse. Data encapsulation led to the important OOP concept of data hiding.

Some key features of the Object Oriented programming are:
- Emphasis on data rather than procedure
- Programs are divided into entities known as objects
- Data Structures are designed such that they characterize objects
- Functions that operate on data of an object are tied together in data structures
- Data is hidden and cannot be accessed by external functions
- Objects communicate with each other through functions
- New data and functions can be easily added whenever necessary
- Follows bottom up design in program design

Q-2.Explain operator overloading and function overloading with example.

Ans:Operator overloading:Operator overloading is a compile-time polymorphism in which the operator is overloaded to provide the special meaning to the user-defined data type. Operator overloading is used to overload or redefines most of the operators available in C++. It is used to perform the operation on the user-defined data type. For example, C++ provides the ability to add the variables of the user-defined data type that is applied to the built-in data types.

The advantage of Operators overloading is to perform different operations on the same operand

Syntax of Operator Overloading

return_type class_name  : : operator op(argument_list)  

     // body of the function.  

Function overloading: Function overloading is a feature in C++ where two or more functions can have the same name but different parameters.

Example:
#include <iostream>
using namespace std;
void display(int);
void display(float);
void display(int, float);
int main() {
int a = 5;
float b = 5.5;
display(a);
display(b);
display(a, b);
return 0;
}
void display(intvar) {
cout<< "Integer number: " <<var<<endl;
}
void display(float var) {
cout<< "Float number: " <<var<<endl;
}
void display(int var1, float var2) {
cout<< "Integer number: " << var1;
cout<< " and float number:" << var2;
} 

 

Q-3.What is Unicode  ? Explain the necessity of using unicode .

Ans:Unicode is anInternational encoding standard for representing characters as integers.Unicode is very important as it is a standard that allows computers to represent and manipulate, consistently, the text of any existing system of writing.

Such as many encoding   UTF(Unicode Transformation Format)-8, UTF-16BE, UTF-32BE, UTF-16LE or UTF-32LE etc.

Unlike ASCII, which uses 7bits for each character, Unicode use 16 bits, which means that can represent more than 65000 unique characters.

-Unicode represents a single encoding scheme for all languages and characters.

-Unicode data can be used through many different systems without data corruption.

-Unicode is the preferred encoding scheme used by XML-based tools and

Applications.

Q-4.What is cache memory? Differentiate between primary memory and cache memory.

Ans: Cache memory(also called CPU memory) is an extremely fast memory type that acts as a buffer between RAM and the CPU.

BASIS FOR COMPARISON	Main memory	Cache memory
Definition	Main memory is also known as Random Access Memory. It is a memory unit that directly interacts with the central processing unit (CPU)	Cache memory is used to store frequently accessed data in order to quickly access the data whenever it is required.
Proximity with CPU	Comparatively far	Comparatively closer
Speed	Comparatively slow	Comparatively fast
Capacity	Larger	Comparatively less
Component	It is a part of the hard drive (secondary storage)	Located on the processor itself

Q-5.What is Multimedia ? What is video conferencing and how it works ?

Ans: Multimedia is the field of Computer Science that integrates different forms of information and represents in the form of audio, video, and animation along with the traditional media, i.e., text, graphics/drawings, images, etc.

·        Multi − it means more than one

·        Medium − it is singular and it means intermediary or mean

·        Media − it is plural and it means conveying the information

Videoconferencing(or video conference) means to conduct a conference between two or more participants at different sites by using computer networks to transmit audio and video data. For example, a point-to-point (two-person) video conferencing system works much like a video telephone.

 Video conferencing programs combine Web page tools and Internet communication into one interface to create an interactive meeting environment. These tools include:

· HTML, XML and ASP markup 

· Java scripts 

· Flash animation 

· Instant messaging 

· Streaming audio and video 

The simplest video conference requires two people, each with: 

· A computer 

· An Internet connection 

· A telephone, if audio content isn't provided online 

· A PC with a microphone, a Webcam or digital video camera, and a video capture card 

Q-6.What disk partitioning? Why is needed ?

Ans: Disk partitioningis one step of disk formatting. It is the process of dividing a disk into one or more regions, the so called partitions. If a partition is created, the disk will store the information about thelocation and size of partitions in partition table that is usually located in the first sector of a disk. 

With the partition table, each partition can appear to the operating system as a logical disk and users can read and write dataon disk. And each partition can be managed separately. 

Some disk partitioning example:

NTFS	A partition used with Microsoft Windows NT 4.x, Windows 2000 and Windows XP.
MINIX	A partition used with the MINIX operating system.
Unix System V (SCO, IRIX, ISC, Unix, UnixWare, etc...)	A partition used with various Unix operating systems.
Linux (Linux native, Linux swap, Linux extended, ext2fs)	A partition used with various variants of the Linux operating systems.

 Why is needed:

·         Faster disk access.

·         Prevents Data overflow.

·         Separate area for swap/paging.

·         Ease of Windows Reinstallation.

·         Easier Backup and recovery.

·         You can use multiple operating systems on the same PC.

·         In the case of operating system failure, your data is less likely to be affected etc.

Q-7.Whst is antivirus ?write some names of antivirus.

Ans:

Antivirus or anti-virus software (abbreviated to AV software), also known as anti-malware software is a program or set of programs that are designed to prevent, search for, detect, and remove software viruses, and other malicious software like worms, trojans, adware, and more.

Some of the antivirus software are as follows :

1.      Bitdefender Family Pack

2.      Trendmicro

3.      Norton 360

4.      AVG

5.      Avira

6.      Mcafee

7.      Watchdog

8.      ESET

9.Kaspersky Lab Internet Security 2017

10. Sophos Home Free Antivirus etc.

Q-8.How to animate slide in MS Power Point.How to add image in slide?

Q-9.Differentiate among Assembler, Compiler and Interpreter

Ans:

Assembler: Assembler converts the assembly code into the machine code. But the Assembler can’t execution whole  program at once.

The output of assembler is binary code.

GAS, GNU is an example of an assembler.

Q-10.Why Java is called both compiled and interpreted language ?

Ans: Java is both compiled and interpreted programming language. Java code is written in .java files (also known as source file), which is compiled by javac, a Java compiler into class files. Unlike C or C++ compiler, Java compiler doesn't generate native code. These class files contains byte-code, which is different than machine or native code. Java virtual machine or JVM interprets byte codes during execution of Java program.

Q-11.Differentiate between linked list and array.Write the pseudo code of adding a node in the end of a singly linked list.

(Differentiate between linked list and array)See- Programmer at Bangladesh National Parliament Secretaritat-2014

Algorithm to insert node at the beginning of Singly Linked List
Being:
createSinglyLinkedList (head)
alloc (newNode)
If (newNode == NULL) then
write ('Unable to allocate memory')
End if
Else then
read (data)wo
newNode.data ← data
newNode.next ← head
head ← newNode
End else
End

Q-12.Draw a binary search tree using the following data:8,10,26,2,78,102 and 115 

Q-13.Describe various steps of software development

Ans:

There are following six phases in every Software development life cycle model:

1.      Requirement gathering and analysis.

2.      Design.

3.      Implementation or coding.

4.      Testing.

5.      Installation/Deployment.

6.      Maintenance.

Q-14.What are truth table,characteristics table and excitation table?

Q-15.What is network topology?Explain various types of network topology .

Ans: Network Topology is the schematic description of a network arrangement, connecting various nodes(sender and receiver) through lines of connection.

 

BUS Topology

Bus topology is a network type in which every computer and network device is connected to single cable. When it has exactly two endpoints, then it is called Linear Bus topology.

Features of Bus Topology

1. It transmits data only in one direction.
2. Every device is connected to a single cable

Advantages of Bus Topology

1. It is cost effective.
2. Cable required is least compared to other network topology.
3. Used in small networks.
4. It is easy to understand.
5. Easy to expand joining two cables together.

Disadvantages of Bus Topology

1. Cables fails then whole network fails.
2. If network traffic is heavy or nodes are more the performance of the network decreases.
3. Cable has a limited length.
4. It is slower than the ring topology.

RING Topology

It is called ring topology because it forms a ring as each computer is connected to another computer, with the last one connected to the first. Exactly two neighbors for each device.

Advantages of Ring Topology

1. Transmitting network is not affected by high traffic or by adding more nodes, as only the nodes having tokens can transmit data.
2. Cheap to install and expand

Disadvantages of Ring Topology

1. Troubleshooting is difficult in ring topology.
2. Adding or deleting the computers disturbs the network activity.
3. Failure of one computer disturbs the whole network.

STAR Topology

In this type of topology all the computers are connected to a single hub through a cable. This hub is the central node and all others nodes are connected to the central node.

Features of Star Topology

1. Every node has its own dedicated connection to the hub.
2. Hub acts as a repeater for data flow.
3. Can be used with twisted pair, Optical Fiber or coaxial cable.

Advantages of Star Topology

1. Fast performance with few nodes and low network traffic.
2. Hub can be upgraded easily.
3. Easy to troubleshoot.
4. Easy to setup and modify.
5. Only that node is affected which has failed, rest of the nodes can work smoothly.

Disadvantages of Star Topology

1. Cost of installation is high.
2. Expensive to use.
3. If the hub fails then the whole network is stopped because all the nodes depend on the hub.
4. Performance is based on the hub that is it depends on its capacity

TREE Topology

It has a root node and all other nodes are connected to it forming a hierarchy. It is also called hierarchical topology. It should at least have three levels to the hierarchy.

Features of Tree Topology

1. Ideal if workstations are located in groups.
2. Used in Wide Area Network.

Advantages of Tree Topology

1. Extension of bus and star topologies.
2. Expansion of nodes is possible and easy.
3. Easily managed and maintained.
4. Error detection is easily done.

Disadvantages of Tree Topology

1. Heavily cabled.
2. Costly.
3. If more nodes are added maintenance is difficult.
4. Central hub fails, network fails.

HYBRID Topology

It is two different types of topologies which is a mixture of two or more topologies. For example if in an office in one department ring topology is used and in another star topology is used, connecting these topologies will result in Hybrid Topology (ring topology and star topology).

Features of Hybrid Topology

1. It is a combination of two or topologies
2. Inherits the advantages and disadvantages of the topologies included

Advantages of Hybrid Topology

1. Reliable as Error detecting and trouble shooting is easy.
2. Effective.
3. Scalable as size can be increased easily.
4. Flexible.

Disadvantages of Hybrid Topology

1. Complex in design.
2. Costly.

MESH Topology:

In flooding, the same data is transmitted to all the network nodes, hence no routing logic is required. The network is robust, and the its very unlikely to lose the data. But it leads to unwanted load over the network.

Features of Mesh Topology

1. Fully connected.
2. Robust.
3. Not flexible.

Advantages of Mesh Topology

1. Each connection can carry its own data load.
2. It is robust.
3. Fault is diagnosed easily.
4. Provides security and privacy.

Disadvantages of Mesh Topology

1. Installation and configuration is difficult.
2. Cabling cost is more.
3. Bulk wiring is required.