Signal is a physical quantity that varies with time ,space, or any other independent variable or variable

If a signal depends on one variable is called - One dimensional signal

If a signal depends on Two variable is called - Two Dimensional Signal

Representation of signal by mathematical equation is called Signal Modeling

If one can represent signal in mathematical equation is said to be Deterministic signal

If we are not able to represent the equation in mathematical form is called as Random Signal 

Thiruvanathapuram

Niels Bohr

discovered the structure of atom

Rhizobium & Azetobactor

The nitrogen cycle is an biogeochemical essential process that converts different forms of nitrogen and compounds of nitrogen into forms that can be utilized for life processes. The limiting factor is that atmospheric nitrogen (N2) is unavailable to most organisms due to the high amount of energy required to break the triple bond between the two atoms of nitrogen. Alternatively, other forms of nitrogen, such as ammonia (NH3+), is converted to soluble forms of nitrogen compounds, including nitrites and nitrates that can be utilized. The utilisation of nitrogen is a complex process that involves many different chemical reactions by different organisms.

Nitrogen fixation is the process of converting nitrogen gas to a fixed form which is a nitrogenous compound, such as ammonia (NH3) or ammonium (NH4+). The reaction generates hydrogen gas, which can be utilized to reduce molecular oxygen and generate electrons and ATP. The equation for this reaction in most nitrogen fixing organisms, such as Rhizobium and Azotobacter

J.C. Bose

Sir Jagadish Chandra Bose, CSI, CIE, FRS was a Bengali polymath, physicist, biologist, botanist, archaeologist, as well as an early writer of science fiction. Wikipedia
Born: November 30, 1858, Bikrampur
Died: November 23, 1937, Giridih
Spouse: Abala Bose (m. 1887)
Parents: Bhagawan Chandra Bose
Education: Hare School, St. Xavier's College, Kolkata, more
Books: Sir Jagadis Chunder Bose His Life and Speeches, more

View more @ Wikipedia

Aristotle

Philosopher

Aristotle was a Greek philosopher and scientist born in the Macedonian city of Stagira, Chalkidice, on the northern periphery of Classical Greece. Wikipedia

Born: 385 BC, Stagira, Greece

Died: 322 BC, Chalcis, Greece

Full name: Aristotle

Nationality: Greek

Education: Platonic Academy (367 BC–347 BC)

Calculating Square of numbers quickly...

Lets calculate the square of 54

So (54)^2 = 5^2 +4 -- 4^2 = 25 +4 ----16 =29-------16= 2916

 (55)^2 = 5^2 +5 --5^2=25+5------25=30---------25= 3025

 (56)^2 = 5^2 + 6--6^2=25+6------36= 31--------36= 3136 etc..

---

Multiply any large number by 12 mentally in seconds

To multiply any number by 12 just double last digit and thereafter double each digit and add it to its neighbour

For example 21314 * 12 = 255768

Lets break it into simple steps:

Step 1: 021314 * 12 = _____8 (Double of Last Digit 4= 8 )

Step 2: 021314 * 12 = ____68 (Now Double 1= 2, and add it to 4, 2+4=6)

Step 3: 021314 * 12= ___768 (Now Double 3=6, and add it to 1, 6+1=7)

Step 4: 021314 * 12= __5768 (Now Double 1=2, and add it to 3, 2+3=5)

Step 5: 021314 * 12= _55768 (Now Double 2=4, and add it to 1, 4+1=5)

Step 6: 021314 * 12= 255768 (Now Double 0=0, and add it to 2, 0+2=2)

So your final answer of 21314 * 12 = 255768

Is 456138 divisible by 9?

Now, it only takes 2 seconds for you to determine the answer.

No let see the solution

To test whether a certain large number is divisible by 9 or not,'just add all the digits of the number and if the end result is divisible by 9,then you can say that the entire large number will be divisible by 9 too'.

4+5+6+1+3+8=27

Now since 27 is divisible by 9 so 456138 will be divisible by 9 too.

43*11

To multiply 43 and 11,imagine there is a space between 43

43*11= 4_3 (Put an imaginary space in between)

Now,what to do with that space?

Just add 4 and 3 and put the result in the imaginary space

So, 43 * 11 =473 (which is your answer)

Isn't it great?

Lets try some more examples:

1) 35 * 11 = 3 (3+5) 5 = 385

2) 81 * 11 = 8 (8+1) 1 = 891

3) 72 * 11 = 7 (7+2) 2 = 792 etc..

INDIAN DEFENCE DAYS

Better to remember Short this as M A N Days

(Military-Army-Navy)

Military -First month Navy-Last month

Military(8)+Januvary( 7)=15

Military day=Januvary 15

Territorial Army day=october 9

Air Force day =october 8

Navy (4)=december 4

You can connect two computers wirelessly directly without a router/access point by setting up an ad-hoc wireless network, as long as both have compatible wireless adapters.

Such ad-hoc wireless network is easy to configure, it can be up and running within minutes. The main disadvantage is limited range - wireless coverage is limited by the capability of your wireless adapters, that is usually lower than a router/access point.
You can have up to 9 wireless clients in an ad-hoc wireless network.
Here are some pointers to set up an ad hoc network under Windows XP:
Host computer configuration - you may want to set up ICS (Internet Connection Sharing) on a host computer to share the internet connection. If ICS is enabled on a host computer, the clients will be able to obtain IP adresses automatically from it.

1. Right-click the wireless adapter icon in the system tray and choose "Properties"
2. Choose the "Wireless Networks" tab and click "Advanced".
3. Select the "Computer-to-computer (ad hoc) networks only" option and click "close". Don't tick the "Automatically connect to non-preferred networks" in order to ease the configuration.
4. In the "Preferred networks" dialog, click "Add" to add a new ad hoc wireless network.
5. Name your ad hoc network, try to use "open authentication" without encryption first. Enable WPA or WEP encryption only after testing.
6. After clicking "OK" you should see your newly created ad hoc network in the preferred networks list. You're done with the host computer configuration.

Client Computer configuration

1. Right-click the wireless adapter icon in the system tray and choose properties.
2. You need to set the wireless adapter to "use Windows to configure its network settings" and enable "Computer-to-computer (ad hoc) networks only". Simply follow the same steps as the host computer configuration.
3. Right-click the wireless adapter icon to "view available wireless networks", and you should see your ad hoc wireless netwok name - proceed to connect to it. At that stage you should be able to connect to it.
Note: If you have ICS enabled on the host computer, you can just set each client adapter to obtain an IP address automatically. Otherwise, you will need to allocate a static IP address in the same subnet to each device in the ad-hoc network (done from the Network Adapter properties dialog, TCP/IP v.4).

Example           Operation              Result 
-$a               Negation               Negative value of $a 
$a + $b           Addition               Sum of $a and $b 
$a - $b           Subtraction            Difference of $a and $b 
$a * $b           Multiplication         Product of $a and $b 
$a / $b           Division               Quotient of $a and $b 
$a % $b           Modulus                Remainder of $a divided by $b
  
  

<html>
<head>
<title>Adding a Row to a Database</title>
</head>
<body>
<div>
<?php
$user = "root";
$pass = "";
$db = "mydatabase";
$link = @mysql_connect( "localhost", $user, $pass );
if ( ! $link ) {
  die( "Couldn't connect to MySQL: ".mysql_error() );
}
print "<h2>Successfully connected to server</h2>\n\n";
@mysql_select_db( $db ) or die ( "Couldn't open $db: ".mysql_error() );
print "Successfully selected database \"$db\"<br />\n";

$query = "INSERT INTO domains( domain, sex, mail )values( 'example.com', 'F', 'a@example.com' )";
print "running query: <br />\n$query<br />\n";
mysql_query( $query, $link ) or die ( "INSERT error: ".mysql_error() );
mysql_close( $link );
?>
</div>
</body>
</html>

<?php
header("Content-type: image/gif");
$cells = array ( liked=>200, hated=>400, indifferent=>900 );
$max = max( $cells );
$total = count ( $cells );
$totalwidth = 300;
$totalheight = 200;
$xgutter = 20; // left/right margin
$ygutter = 20; // top/bottom margin
$internalgap = 10; // space between cells
$bottomspace = 30; // gap at the bottom (in addition to margin)
$font = "ARIALBD.TTF";
 $graphCanX = ( $totalwidth - $xgutter*2 );
$graphCanY = ( $totalheight - $ygutter*2 - $bottomspace );// starting draw position x - axis
$posX = $xgutter; // starting draw pos - y -  axis
$posY = $totalheight - $ygutter - $bottomspace;
$cellwidth = (int) (( $graphCanX - ( $internalgap * ( $total-1 ) )) / $total) ;
 $textsize = (int)($bottomspace);
// adjust font size
while ( list( $key, $val ) = each ( $cells ) )
    {
     while ( 1 )
        {
        $box = ImageTTFbBox( $textsize, 0, $font, $key );
        $textWidth = abs( $box[2] );
        if ( $textWidth < $cellwidth )
            break;
        $textsize--;
        }
    }
$image = imagecreate( $totalwidth, $totalheight );
$red = ImageColorAllocate($image, 255, 0, 0);
$blue = ImageColorAllocate($image, 0, 0, 255 );
$black = ImageColorAllocate($image, 0, 0, 0 );
$grey = ImageColorAllocate($image, 100, 100, 100 );
 reset ($cells);
 while ( list( $key, $val ) = each ( $cells ) )
     {
     $cellheight = (int) (($val/$max) * $graphCanY);
     $center = (int)($posX+($cellwidth/2));
    imagefilledrectangle( $image, $posX, ($posY-$cellheight), ($posX+$cellwidth), $posY, $blue );
     $box = ImageTTFbBox( $textsize, 0, $font, $key );
     $tw = $box[2];
     ImageTTFText(    $image, $textsize, 0, ($center-($tw/2)),
             ($totalheight-$ygutter), $black, $font, $key );
     $posX += ( $cellwidth + $internalgap);
     }
 imagegif( $image );
 ?>