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.