UGC Net Answer Key December 2014

Visual Basic .Net Window Programming

Horizontal and Vertical Scroll Bar,Numeric Scroll Bar,Progress Bar and Domain Name Scroll Bar Demo

Public Class Form1

    Dim i As Integer

    Private Sub VScrollBar1_Scroll_1(ByVal sender As System.Object, ByVal e As System.Windows.Forms.ScrollEventArgs) Handles VScrollBar1.Scroll

        lblR.Text = VScrollBar1.Value

        Me.BackColor = Color.FromArgb(VScrollBar1.Value, VScrollBar2.Value, VScrollBar3.Value)

    End Sub

C# Window Programming

Combo Box

A combo box is a commonly used graphical user interface widget (or control). Traditionally, it is a combination of a drop-down list or list box and a single-line editable textbox, allowing the user to either type a value directly or select a value from the list. The term "combo box" is sometimes used to mean "drop-down list". In both Java and .NET, "combo box" is not a synonym for "drop-down list". Definition of "drop down list" is sometimes clarified with terms such as "non-editable combo box" (or something similar) to distinguish it from "combo box".

C# Basic Concept and Tutorial

Static Classes

A class can be declared static, which indicates that it contains only static members. It is not possible to use the new keyword to create instances of a static class. Static classes are loaded automatically by the .NET Framework common language runtime (CLR) when the program or namespace that contains the class is loaded.

Use a static class to contain methods that are not associated with a particular object. For example, it is a common requirement to create a set of methods that do not act on instance data and are not associated to a specific object in your code. You could use a static class to hold those methods.

Following are the main features of a static class:

·         They only contain static members.

·         They cannot be instantiated.

·         They are sealed.

·         They cannot contain Instance Constructors (C# Programming Guide).

Creating a static class is therefore basically the same as creating a class that contains only static members and a private constructor. A private constructor prevents the class from being instantiated.

The advantage of using a static class is that the compiler can check to make sure that no instance members are accidentally added. The compiler will guarantee that instances of this class cannot be created.

Static classes are sealed and therefore cannot be inherited. They cannot inherit from any class except Object. Static classes cannot contain an instance constructor; however, they can have a static constructor. For more information

Static Members

A static method, field, property, or event is callable on a class even when no instance of the class has been created. If any instances of the class are created, they cannot be used to access the static member. Only one copy of static fields and events exists, and static methods and properties can only access static fields and static events. Static members are often used to represent data or calculations that do not change in response to object state; for example, a math library might contain static methods for calculating sine and cosine.

Static methods can be overloaded but not overridden.

Static class members are declared by using the static keyword before the return type of the member, for example:

C# Programming Practical Questions

Question : Write a program which accept input of full path of a file and produce following output?
Input : C:/Users/Public/Pictures/SamplePictures/Desert.jpg
Output :
Extension : jpg
File Name : Desert
Path : C:/Users/Public/Pictures/SamplePictures


Solution :


import java.util.*;
public class Main
{


       public static void main(String[] args)
    {
        String str;
        Scanner sc=new Scanner(System.in);
        System.out.print("Enter your name>> ");
        str=sc.nextLine();


        int ep,sp;
        ep=str.indexOf(".");
        sp=str.lastIndexOf("\\");
        System.out.print("\nExtention  is "+str.substring(ep+1,str.length()));
        System.out.println("\nFile Name is "+str.substring(sp+1,ep));
        System.out.println("\npath is "+str.substring(0,sp));




    }
}

C# Tutorial and Notes

Static Classes

A class can be declared static, which indicates that it contains only static members. It is not possible to use the new keyword to create instances of a static class. Static classes are loaded automatically by the .NET Framework common language runtime (CLR) when the program or namespace that contains the class is loaded.

Use a static class to contain methods that are not associated with a particular object. For example, it is a common requirement to create a set of methods that do not act on instance data and are not associated to a specific object in your code. You could use a static class to hold those methods.

Following are the main features of a static class:

·         They only contain static members.

·         They cannot be instantiated.

·         They are sealed.

·         They cannot contain Instance Constructors (C# Programming Guide).

Creating a static class is therefore basically the same as creating a class that contains only static members and a private constructor. A private constructor prevents the class from being instantiated.

The advantage of using a static class is that the compiler can check to make sure that no instance members are accidentally added. The compiler will guarantee that instances of this class cannot be created.

Static classes are sealed and therefore cannot be inherited. They cannot inherit from any class except Object. Static classes cannot contain an instance constructor; however, they can have a static constructor. For more information

Static Members

A static method, field, property, or event is callable on a class even when no instance of the class has been created. If any instances of the class are created, they cannot be used to access the static member. Only one copy of static fields and events exists, and static methods and properties can only access static fields and static events. Static members are often used to represent data or calculations that do not change in response to object state; for example, a math library might contain static methods for calculating sine and cosine.

Static methods can be overloaded but not overridden.

Static class members are declared by using the static keyword before the return type of the member, for example:

File Management in C Languge

Formatted Input in a file

#include<stdio.h>

#include<conio.h>

void main()

{

int roll,i;

char nm[10],ct[10];

FILE *ft;

clrscr();

ft=fopen("abc.doc","w");

for(i=1;i<=3;i++)

{

printf("Enter %d'st roll>> ",i);

scanf("%d",&roll);

fflush(stdin);

printf("Enter %d'st name>> ",i);

gets(nm);

fflush(stdin);

printf("Enter %d'st City>> ",i);

gets(ct);

fprintf(ft,e"%d\t%s\t%s\n",roll,nm,ct);

}

}

Output Device

CRT

The cathode ray tube (CRT) is a vacuum tube containing an electron gun (a source of electrons or electron emitter) and a fluorescent screen used to view images. It has a means to accelerate and deflect the electron beam(s) onto the fluorescent screen to create the images. The image may represent electrical waveforms (oscilloscope), pictures (television, computer monitor), radar targets and others. CRTs have also been used as memory devices, in which case the visible light emitted from the fluoresecent material (if any) is not intended to have significant meaning to a visual observer (though the visible pattern on the tube face may cryptically represent the stored data)

LCD

A liquid-crystal display (LCD) is a flat panel display, electronic visual display, or video display that uses the light modulating properties of liquid crystals. Liquid crystals do not emit light directly.

Input Device

In computing, an input device is any peripheral (piece of computer hardware equipment) used to provide data and control signals to an information processing system such as a computer or other information appliance. Examples of input devices include keyboards, mice, scanners, digital cameras and joysticks.

Input Devices Before computers, the phrase "input device" probably was not on the tip of anyone's tongue. It has a dry and impersonal sound, sorta technical - rather like computer talk, don't you think? The phrase is easy to define because a "device" is an instrument that performs a simple task. "Input" is also easy - something put into a system. So in the technology world...
an input device is any tool that feeds data into a computer. For example, a keyboard is an input device, whereas a display monitor is an output device. Mice, trackballs, and light pens are all input devices. Isn't it amusing that under the dry title of "input devices," we get such fun words as mice, joystick, trackball, touch pad, light pen, and puck?

Keyboards

The input of information into your computer is generally done through your keyboard and your mouse or mouse substitute. The keyboard has the distinction of being the standard input device.
The variety of keyboards is almost staggering. No one has to stick with the standard keyboard that comes with the computer. Ergonomically designed keyboards often have unusual sculpted or contoured shapes and a space age look. These keyboards are designed to help avoid repetitive stress injury to the wrists. Some of these keyboards come with foot pedals to spread the work to other limbs. Some keyboards are even designed to take advantage of the strength in the thumbs.
Other keyboards come with extra large keys to help users with sight or hand coordination problems. Wireless keyboards can offer the freedom from being tethered to the computer. In keyboards, if you shop around, you will find that there really is something for everyone.
Your choice of keyboard, like your choice of any input device, is a very personal matter. If only we could test each type of keyboard or mouse for an extended period of time before buying one, but that just doesn't happen in today's marketplace. Computer users should research the many different products offered. Make sure you know if and how you can customize the input device for your own use. Only you can decide which kind of device is most comfortable for you. And that applies to all input devices.

Operating System

Types of Operating System

Types of Operating System

Overlays

     One of the main limitations imposed on programmers in the early days of computing was the size of the computer's memory. If the program was larger than the available memory, it could not be loaded, which placed severe restrictions on program size. The obvious solution would be to increase the amount of memory available, but this would significantly increase the cost of the computer system. One way for a programmer to overcome these limitations was to use overlays. The programmer divided the program into a number of logical sections. A small portion of the program had to remain in memory at all times, but the remaining sections (or overlays) were loaded only when they were needed. The use of overlays allowed programmers to write programs that were much larger than physical memory, although responsibility for managing memory usage rested with the programmer rather than the operating system.

• The entire program and data of a process must be in the physical memory for the process to execute.
• The size of a process is limited to the size of physical memory.
• If a process is larger than the amount of memory, a technique called overlays can be used.
• Overlays is to keep in memory only those instructions and data that are needed at any given time.
• When other instructions are needed, they are loaded into space that was occupied previously by instructions that are no longer needed.
• Overlays are implemented by user, no special support needed from operating system, programming design of overlay structure is complex

Page Stealing

When this supply becomes low, OS uses page stealing to replenish it, that is, it takes a frame assigned to an active user and makes it available for other work. The decision to steal a particular page is based on the activity history of each page currently residing in a central storage frame. Pages that have not been active for a relatively long time are good candidates for page stealing.

Belady's Anamaly

This is a stage which occurs in FIFO page replacement algorithm, in which  a large number of page fault happens.

Preemptive scheduling

Task are usually assigned with priority at times it is necessary to run a certain task that has higher priority before another task although it is running  therefore the running task is interrupted for some time and resumes later when the priority task has finished its execution. This is called preemptive scheduling

E.g. Round-Robin

Non-Preemptive 

 In non preemptive scheduling a running task is executed till. it cannot be interrupted

E.g. FIFO 

Computer Memory

Memory

In computing, memory refers to the physical devices used to store programs (sequences of instructions) or data (e.g. program state information) on a temporary or permanent basis for use in a computer or other digital electronic device. The term primary memory is used for the information in physical systems which function at high-speed (i.e. RAM), as a distinction from secondary memory, which are physical devices for program and data storage which are slow to access but offer higher memory capacity. Primary memory stored on secondary memory is called "virtual memory".

Characteristics

Volatile memory

Volatile memory is a type of storage whose contents are erased when the system's power is turned off or interrupted. For example, RAM is volatile; meaning users will lose a document if they do not save their work to a non-volatile classification of memory, such as a hard drive, before shutting down the computer.

Non-volatile

Non-volatile is a term used to describe any memory or storage that is saved regardless if the power to the computer is on or off. The best example of non-volatile memory and storage is a computer hard drive, flash memory, and ROM. If data is stored on a hard drive, it will remain on that drive regardless if the power is interrupted, which is why it is the best place to store your data and documents. This is also how your computer keeps the time and other system settings even when the power is off.

Hamming Code

Data Error

Data error is term which occurs when we send data and it’s not received as we send.

Error Type

There are two type of error single bit and multiple bits (Burst)

Error detection and Correction

Error detection technique are user detect an error on the other hand error correction technique enable us to resolve an error. We can remove one, two and three bit error only because burst error may occur extremely.

Hamming code

Hamming code is a set of error-correction code s that can be used to detect and correct bit errors that can occur when computer data is moved or stored. Hamming code is named for R. W. Hamming of Bell Labs.

New Exam Pattern for UGC NET for Dec 2014

After UGC's failure, CBSE to conduct NET

NEW DELHI: Central Board of Secondary Education, the country's largest exam conducting body, is all set to add another test to its bouquet, the National Eligibility Test. The inclusion of the test from this year will make the board the biggest exam conducting body, with the number of CBSE candidates set to cross 65 lakh in a year.

After failing to conduct the test without hiccups, the University Grants Commission, with the HRD ministry's consent, has asked the CBSE to conduct the test. The decision was taken at the full commission meeting on Tuesday with near unanimity. The NET is conducted twice a year for grant of junior research fellowship and eligibility for assistant professor in institutions of higher learning.

Add an image to Google

To include a picture in Google search results, the first step is to add your image to a website along with a descriptive text for your image. While you can’t directly upload images into search results, searchable images that are posted on a website can be added to our search results.

                              

Step for upload your Image

• If you have a website then upload your image their 

september 1752 calendar missing days reason

In September 1752 the Julian calendar was replaced with the Gregorian calendar in Great Britain and its American colonies. The Julian calendar was 11 days behind the Gregorian calendar, so 14 September got to follow 2 September on the day of the change. The result was that between 3 and 13 September, absolutely nothing happened!

How to create automatic password using php

Password is widely used in computer as a security mechanism so we must make a password in such a manner which cannot be   guessable by any one. Mostly peoples make password pattern related to their life i.e. date of birth,city name,address or something like that which can be guess easily. So we must stop this practice, A strong password may be difficult to guess.

A strong password comprises special character, numeric, small and capital case character combination that restricts hacker to guess it. So I am representing coding that generate password automatically in strong form. You can use my coding if you want to generate password automatically.

<?php

                $msg="";

                 function makeRandomString ($length=8)

              {

                  $chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQ

                  RSTUVWXYZ0123456789!%,-:;@_{}~";

                  for ($i = 0, $makepass = '', $len = strlen($chars); $i < $length;

                  $i++) $makepass .= $chars[mt_rand(0, $len-1)];

                  return $makepass;

       }

                if(isset($_POST['pass']))

                                $msg=makeRandomString(10);

?>

<html>

<head>

<title>Untitled Document</title>

</head>

<body>

                <form action="<?php echo $_SERVER['PHP_SELF']?>" method="post" >

                <input type="submit" value="Get password" name="pass" />

        <h1><?php echo $msg;?></h1>

    </form>

</body>

</html>

Girfa Pics

Picture

A picture is a visual capture of an object. Pictures are created using another hardware device such as a digital camera or a scanner and not the computer. The picture of pictures shown here is a good example of a picture.

How to Add a Widget to Blogger

Widgets, also known as gadgets, are small tools or applications that can be added to a website or blog to enhance its content or functions, or to pull content and services from third-party websites. Widgets come in multiple forms, such as countdown tickers, photos, games, or interactive social media applications that allow you to chat. Some widgets in Blogger serve the purpose of enhancing your blog, such as listing your blog followers or allowing readers to subscribe to your blog content. Here are steps on how to add a widget to Blogger.

PHP Paging

I have made a website for flat selling. Many customer enquiries daily for flat booking by filling enquiry form. I have made an admin page which shows enquiry data of customer, everything was ok but when enquiry got increase then admin page data also increase so my client had to scroll very long that was not a good interface. So I decided to show enquiry table content page wise.

Thanks to limit clause used by MYSQL. You can use limit clause with select statement for limit the returns row from database, its takes two clause as a record number start and stop

I.e. Select * from Enquiry limit 0, 10

You can change limit clause argument for desire row, fist number for start and second one stand for stop retrieving row form table.

Click here to download full example

Core Java Programming

This post is for student who study java and they need many programs in their exam and test so I am trying to make some java programs which help them to make their work easy 

Question : Write a program which accept input of full path of a file and produce following output?

Input : C:/Users/Public/Pictures/SamplePictures/Desert.jpg

Output :

Extension : jpg

File Name : Desert

Path : C:/Users/Public/Pictures/SamplePictures

Solution :

import java.util.*;

public class Main

{

       public static void main(String[] args)

    {

        String str;

        Scanner sc=new Scanner(System.in);

        System.out.print("Enter your name>> ");

        str=sc.nextLine();

How to send email a form data using php

Form is a electronic way where organization gathered data from user through website. A website owner usually take details of esquires to his website using login provide by the website developer.

But we are familiar with email because it’s an era  of android word and every one configure email with mobile so sending form data in email as well as database is a good idea.

PHP provide a easy way to achieve this just take a look on flowing code and please don’t say thanks to me.

                    $to =' rajkumar9795@gmail.com';

                  $subject = 'Enquiry Data';

                  $message = "<h2>Welcome This is Enquiry for Now</h2><hr>Name : $_POST[name]<br>Gender :  $_POST[gen]<br>Course : $_POST[course]<br> Email : $_POST[email]<br>Mobile : $_POST[phone]<br>Query : $_POST[query]";

                 

                  $headers = 'From: bcmt@basantgroupofinstitution.org' . "\r\n" .

                                  'Reply-To: basantcollege.mt@gmail.com' . "\r\n" .

                                  'X-Mailer: PHP/' . phpversion().

'MIME-Version: 1.0' . "\r\n".

'Content-type: text/html; charset=iso-8859-1' . "\r\n";

                 

                            mail($to, $subject, $message, $headers);                                                

Window 7 Shortcut Keys

General Keyboard Shortcut
F1	Display Help
Ctrl+C	Copy the selected item
Ctrl+X	Cut the selected item
Ctrl+V	Paste the selected item
Ctrl+Z	Undo an action
Ctrl+Y	Redo an action
Delete	Delete the selected item and move it to the Recycle Bin
Shift+Delete	Delete the selected item without moving it to the Recycle Bin first
F2	Rename the selected item
Ctrl+Right Arrow	Move the cursor to the beginning of the next word
Ctrl+Left Arrow	Move the cursor to the beginning of the previous word
Ctrl+Down Arrow	Move the cursor to the beginning of the next paragraph
Ctrl+Up Arrow	Move the cursor to the beginning of the previous paragraph
Ctrl+Shift with an arrow key	Select a block of text

Window 7 Basic and Tutorial

The desktop (overview)

The desktop is the main screen area that you see after you turn on your computer and log on to Windows. Like the top of an actual desk, it serves as a surface for your work. When you open programs or folders, they appear on the desktop. You can also put things on the desktop, such as files and folders, and arrange them however you want.

The desktop is sometimes defined more broadly to include the taskbar. The taskbar sits at the bottom of your screen. It shows you which programs are running and allows you to switch between them. It also contains the Start button, which you can use to access programs, folders, and computer settings.

Working with desktop icons

Icons are small pictures that represent files, folders, programs, and other items. When you first start Windows, you'll see at least one icon on your desktop: The Recycle Bin (more on that later). Your computer manufacturer might have added other icons to the desktop. Some examples of desktop icons are shown below.

Examples of desktop icons

Double-clicking a desktop icon starts or opens the item it represents.

How to Find a Computer's MAC Address (Windows 7 and Vista)

A media access control address (MAC address) is a unique identifier assigned to network interfaces for communications on the physical network segment. MAC addresses are used as a network address for most IEEE 802 network technologies, including Ethernet. Logically, MAC addresses are used in the media access control protocol sublayer of the OSI reference model.
You can see your mac address by using following steps

    open start menu and Type ncpa.cpl into the search box and press ENTER as in image.

Right-click your Local Area Connection and select Status or just double click on Local Area Icon

Compare date in php

It’s really a horrible thing to work on date to being a programmer. If language is PHP then it’s too hard to achieve but don’t worry I have a best trick to solve it just take a look on following lines.

In PHP Date store in string format internally and time is store integer internally. You just have to change date into its equivalent time integer value and compare their integer as we work on number.

function compare_date($d1,$d2)

{

$date1=strtotime($d1);

$date2=strtotime($d2);

if($date1>$date2)

echo "First Date is greatest one";

else

echo "Second Date is greatest one";

}

I am using function for implement your logic you can work it where you want without using function 

First Things of Computer world

First Email Message

Ray Tomlinson

The first email was sent by Ray Tomlinson to himself in 1971. "The test messages were entirely forgettable. . . . Most likely the first message was QWERTYIOP or something similar," he said.

First Domain 

The first domain registered in 15-March 1985 named symbolics.com

Which is better between LCD screen and LED Screen

The differences between LED and LCD TV to a consumer as well as from the technical point of view are as follows:-
1. The viewing angle of LCD TV is less than that of LED TVs. LCD TVs are best viewed directly from in front and at the same plane as the screen i.e. a good view is not possible if viewed from the sides or from above or below the TV screen. LED TVs, on the other hand, has greater viewing angle.

2. LCD TVs can not be viewed under bright environment whereas LED TVs can be viewed even under direct sunlight. This is so because, the screen of LCD TVs made up of liquid crystals which changes color on passing current though it. Unlike LCD TVs, LED TV screens are made up of Light Emitting Diodes. Therefore, each tiny dot of light (pixel) on LED TV screen is like a light bulb and its glow is visible even under direct sunlight. For example, LCD TVs have the same screens as mobile phones and is not clearly visible under bright sunlight. You must have noticed that some mobile phones have light (a mobile torch).This torch is made up of an LED and thousands of such 'torch' form the LED TV screen.

Working With Document Versions

When you store a version of your document using the versions feature, you can access previous versions, delete any of the versions stored with your document, and recover document versions to a new file.

To view a version of your document
1. Select Versions… from the File menu
2. In the Versions dialog box, highlight the version you would like to open
3. Click Open

Captcha Using PHP

CAPTCHA  which stands for “Completely Automated Public Turing test to tell Computers and Humans Apart” is a type o f challenge-response test to ensure that the response is only generated by humans and not by a computer.

In simple words, CAPTCHA is the word verification test that you will come across the end of a sign-up form while signing up for Gmail or Yahoo account. The following image shows the typical samples of CAPTCHA.

You can make captcha using PHP. Here I am making number captcha which is achieved by an image. This image text is dynamically create by php and stored in session. A user can verify whether valid captcha has been entered or not.

Save this code in named captch.php

<?php 

session_start(); 

$text = rand(10000,99999); 

$_SESSION["vercode"] = $text; 

$height = 25; 

$width = 65; 

  

What is the Difference Between Electronic and Electric?

In a number of instances, people tend to use the terms electronic and electricinterchangeably. While both terms are commonly employed when discussing electronics, there is a subtle difference between the correct usage of each word. Here is what you should know about the proper way to make use of both electronic and electric when speaking or writing.


Electric has to do with the general concept of electricity. It is generally acceptable to use the terms electric and electrical interchangeably. Essentially, the word "electric" will function as a way of qualifying the flow of electricity as it relates to a specific event. For example, if a fire starts due to a problem with wiring in a building, the event can be described as an electric or electrical fire, caused by the electric or electrical wiring. The use of electric identifies a source of power that serves to create a logical effect when conducted through a process or device.

Time Measurement Unit

Units for measuring time

half-hour

 NOUN

a period of 30 minutes

hour

 NOUN

a period of time that consists of 60 minutes. 30 minutes is usually called half an hour, 15 minutes can be called a quarter of an hour,and 45 minutes can be called three-quarters of an hour

hr

 ABBREVIATION

hour

m

 ABBREVIATION

minute

Shannon Channel Capacity

In 1944 Claude Shannon introduce a formula to determine the theoretical highest data rate for a a channel

C=B log 2(1+S/n)

In this formula, B is the bandwidth of the channel. S/N is the signal to noice ratio and C is the capacity (Shannon Capacity) in BPS.

We can calculate the theoretical highest bit rate of regular telephone.

A Telephone line normally has a bandwidth of 3000Hz. The signal to noise ratio is usually 3162-(35db) for this channel capacity is

       C=B log ₂ (1+S/N)

       C=3000 log₂ ⁽(1+3162)

       C=3000 log₂ (3163)

       C=3000*1162

       C=34860 BPS

TCP/IP or OSI - Which one came first

The TCP/IP model, which is realistically the Internet Model, came into existence about 10 years before the OSI model.

History of TCP

       From 1973 to 1974, Cerf's networking research group at Stanford worked out details of the idea, resulting in the first TCP specification. A significant technical influence was the early networking work at Xerox PARC, which produced the PARC Universal Packet protocol suite, much of which existed around that time.

        In March 1982, the US Department of Defense declared TCP/IP as the standard for all military computer networking. In 1985, the Internet Advisory Board (later renamed the Internet Architecture Board) held a three-day workshop on TCP/IP for the computer industry, attended by 250 vendor representatives, promoting the protocol and leading to its increasing commercial use.

        In 1985, the first Interop conference focused on network interoperability by broader adoption of TCP/IP. The conference was founded by Dan Lynch, an early Internet activist. From the beginning, large corporations, such as IBM and DEC, attended the meeting. Interoperability conferences have been held every year since then. Every year from 1985 through 1993, the number of attendees tripled

Lempel–Ziv–Welch Compression

Lempel–Ziv–Welch (LZW) is a universal lossless data compression algorithm created by Abraham Lempel, Jacob Ziv, and Terry Welch. The algorithm is simple to implement, and has the potential for very high throughput in hardware implementations. It was the algorithm of the widely used Unix file compression utility compress, and is used in the GIF image format.Its works like index backside of our notebook.

• I am taking string pattern for elaboration to show compression.
• Make your choice that how much character you want to take, I am taking 4 character maximum for dictionary entry
  

Algorithms

Upper and Lower bound of a function

Upper Bound : Proving an upper bound means you have proven that the algorithm will use no more than some limit on a resource.

Lower Bound : Proving a lower bound means you have proven that the algorithm will use no less than some limit on a resource.


Upper and lower bounds have to do with the minimum and maximum "complexity" of an algorithm (I use that word advisedly since it has a very specific meaning in complexity analysis).

Take, for example, our old friend, the bubble sort. In an ideal case where all the data are already sorted, the time taken is f(n), a function dependent on n, the number of items in the list. That's because you only have to make one pass of the data set (with zero swaps) to ensure your list is sorted.

In a particularly bad case where the data are sorted in the opposite to the order you want, the time taken becomes f(n2). This is because each pass moves one element to the right position and you need npasses to do all elements.

Huffman Compression and Huffman Tree

Hi folks

We used ASCII code for represent character inside of computer. there are two types of ASCII 7 bit and 8bit.8bit ASCII is known as extended ASCII.

In 7 bit ASCII if represent text  following manner 

ABCDACDCAB     (Each character takes 7 bit)

Total Bit   = No. of character * 7

Total Bit   =  10*7

Total Bit   = 70

If consider frequency of character then we’ll find

Frequency of A = 3

Frequency of B = 2

Frequency of C = 3

Frequency of D = 2

In 7 bit ASCII we can represent 127 characters but it’s not always necessary that each character appeared in string as in our example string. There is only four characters which are repeated  so if we used 3 bit for code then we’ll save some bit

i.e. A=000

      B=001

      C=100

      D=101

Now total bit required 10*3 which is 30 instead of 70.

Database Key

Database is a repository of any organization data. It takes data save it and provides many types of sophisticated services for record insert, update, delete, backup and many more. Here I am interested to explain many types of key.

Database : Database is a collection of related table.

Table : A Table is a collection of related records.

Record : A record is a collection of related fields

Field : A fields or attribute is a smallest individual unit of table.

NULL : NULL is a systematic approach treat blank value which is not available current but might be appear in future.

Key : Key is use to identified a record between records set.

How to make Gmail Signature and confidential Message

What is Gmail Signature

A signature is a bit of text (such as your contact information or a favorite quote) that’s automatically inserted at the bottom of every message you send. Here's a sample signature:

Functional Dependency and Normalization

Purpose of Normalization

Normalization is a technique for producing a set of suitable relations that support the data requirements of an enterprise.

Characteristics of a suitable set of relations include:

- the minimal number of attributes necessary to support the data requirements of the enterprise;
- attributes with a close logical relationship are found in the same relation;
- minimal redundancy with each attribute represented only once with the important exception of attributes that form all or part of foreign keys.

Data Communication and Networking

Line Configuration

A network is a combination of more than one devices which connect from some medium (wire , wireless) called channel line configuration refer physical communication channel access method . Three types of access method are follows..

• Point to Point
• Multi Point

Point to Point

Communication line is not shared in point to point line configuration. A separate link used to connect each device in network. Advantage of point to point line configure is no congestion. Highly and sophisticate security implementation is possible.

The entire capacity of the channel is reserved for transmission between those two devices. Most point-to-point line configurations use an actual length of wire or cable to connect the two ends, but other options, such as microwave or satellite links, are also possible.

Multipoint 

Multipoint (Multidrop line configuration) Communication link is shared between all connected nodes from the network. Two types of multipoint line configuration are follows

Spatial Sharing: If several devices can share the link simultaneously, its called Spatially shared line configuration

Temporal (Time) Sharing: If users must take turns using the link , then its called Temporally shared or Time Shared Line Configuration

Gray Code | Binary to Gray Code and that to Binary Conversion

Binary to gray code conversion

     1. The M.S.B. of the gray code will be exactly equal to the first bit of the given binary number.

 

     2. Now the second bit of the code will be exclusive-or of the first and second bit of the given binary number, i.e if both the bits are same the result will be 0 and if they are different the result will be 1. 

     3. The third bit of gray code will be equal to the exclusive-or of the second and third bit of the given binary number. Thus the Binary to gray code conversion goes on. One example given below can make your idea clear on this type of conversion. 

Get Notes..

Computer Generation

We have study history subject in our school days in those time history was common for all student but in college level its get divided on behalf of time like Ancient, Middle and Modern history. The Topic computer generation is also dividing on time. We read what type of hardware was used on time to time in computers .So Generation is computer history based on hardware. There are five generation

First Computer

There is no easy answer to this question because of all the different classifications of computers. The first mechanical computer created by Charles Babbage doesn't really resemble what most would consider a computer today. Therefore, this document has been created with a listing of each of the computer firsts starting with the Difference Engine and leading up to the types of computers we use today. Keep in mind those early inventions that helped lead up to the computer such as the abacus, calculator, and tablet machines are not accounted for in this document.

Graph Tutorial

Bipartite Graph

A Graph G is divided into two finite Set U,V such that each vertex of U is connected to each vertex of V in  such a manner where no vertex is adjacent of same, i.e. U set vertex will not connected of any other vertex of U.

In bipartite graph it is necessary that each vertex must be connect with different color otherwise graph is not bipartite

Complete bipartite graph

In regular bipartite graph G(U,V) ,each Vertex U(n) and V(n) connected each other 

A complete bipartite graph is a graph whose vertices can be partitioned into two subsets V1 and V2 such that no edge has both endpoints in the same subset, and every possible edge that could connect vertices in different subsets is part of the graph. That is, it is a bipartite graph (V1, V2, E) such that for every two vertices v1  V1 and v2 V2, v1v2 is an edge in E

Database Model

Hierarchical  

A hierarchical database model is a data model in which the data is organized into a tree-like structure. The structure allows representing information using parent/child relationships: each parent can have many children, but each child has only one parent (also known as a 1-to-many relationship). All attributes of a specific record are listed under an entity type.

Example of a hierarchical model

In a database an entity type is the equivalent of a table. Each individual record is represented as a row, and each attribute as a column. Entity types are related to each other using 1:N mappings, also known as one-to-many relationships. This model is recognized as the first database model created by IBM in the 1960s.