Saturday 22 June 2013

RFID Reader


RFID means Radio Frequency Identification.

RFID reader is used to read RFD signals.

Generally we can say that RFID and barcode has same applications. They are used to store details of a particular thing or product.

RFID system consists of an antenna and a receiver, which reads Radio Frequency and transfer into processing device and the transponder or tag which is an integrated circuit containing Radio Frequency circuit and information to be transmitted. The details are stored in this IC.

Tags can carry information about,
  •  Pet owner name and address
  • Cleaning instructions on sweater
  • Auto manufactures use RFID system to move cars through an assembly line.

Difference between RFID and Bar code

In RFID, line-of-sight contact is not needed for reading. While in Bar code, line-of-sight is must.
RFID can done scanning at a greater distance more than 90 feet.

Electronic Scabbing


Adapted from the slang term scab (a strike-breaker or one who crosses a strike line to work in place of striking employees).

Electronic scabbing refers to the practice used by managers and other executives when computer networks are used to transfer e-documents (e.g. accounting, clerical, word processing, database records etc.) to a non-striking work force.




Suppose a company has two branches, one in city A and other in city B. One day employees of B started a strike. Hence all the work in B is in pending. So the managers or other executives send the work through internet to branch A and the employees of that branch will complete the work. This practice is commonly known as electronic scabbing.

Friday 7 June 2013

Number Systems



There are different types of number systems.
Normally we are using Decimal number system. ie, with base 10.
We all know that computer can understand only 0's and 1's. This number system is known as Binary number system. ie, base 2.

The main four number systems are given below,

1. Decimal: Base-10
                    Numbers are 0,1,2,3,4,5,6,7,8,9
                   
                    e.g. (935)10, (541)10, (12378)10 etc


2. Binary: Base- 2
                 Numbers are 0, 1

                 e.g.  (110)2, (1111)2, etc


3. Octal:  Base- 8
                Numbers are  0,1,2,3,4,5,6,7

                e.g. (745)8, (136)8


4. Hexadecimal:  Base- 16

Numbers used are:

Decimal                Hexadecimal

0                                 0
1                                 1
2                                 2
3                                 3
4                                 4
5                                 5
6                                 6
7                                 7
8                                 8
9                                 9
10                              A
11                              B
12                              C
13                              D
14                              E
15                              F

      e.g   (1A65)16, (ABCD)16 etc.

Monday 3 June 2013

ASCII


We all know that computers can understand zeros(0's) and ones(1's) only.
But we are storing files with alphanumeric values and special characters, videos files, audio files etc in computer. Have you ever think about how this is possible ?

We can simply say that by converting into 0's and 1's. But how we can convert all these items into 0's and 1's ?

A method named ASCII is introduced for this purpose. ASCII means American Standard Code for Information Interchange.
ASCII is a 7 bit code. ie, 0-255 digits are there.

On storing any data in a computer, first of all, the computer will  convert that into ASCII. Then we can convert into 0's and 1's.

The ASCII table is given below. From that table, we can find out the ASCII equivalent of a particular character.