Long term storage

The need for sharing programs and data imples the need for long-term storage of information .Long –term storage also allows user the convenience of keeping his programs or data in the computer rather than on some external medium like cards. The problems arising are those of providing easy access, protection against interference and protection against system failure.

Sharing

Concurrent activities may be required to share resources or information. The motivation for this is fourfold. Cost is extravagant to provide sufficient resources for all users separately. Building on the work of others is useful to be able to use other people’s programs or routines. Sharing data may be necessary to use the same data base for several different programs, possibly working for several different users. Removing redundancy is economical to share a single copy of a program between several users , rather than provide a separate copy for each user.Problems associated with sharing are resource allocation simultaneous acess to data , simultaneous execution of programs.

Concurrency:

Concurrency is the existence of several simultaneous or parallel activites. Examples are the overlapping of input and output operations with computation and the coexistence in memory of several user programs. Concurrency raises problems of switching from one activity to another, of protecting one activity against the effects of another and synchronizing activities which are mutually dependent.

Transaction Processing--- Part 2

The real time character of transaction processing derives from the necessity of keeping the data base up to date;clearly the system is useless if transactions are made on incorrect data.Further problems arise in dealing with simultaneous transactions on the same piece of data .The individual user should ofcourse be unaware of these problems,and the operating systems must revolve them so that he has the impression of being the sole user of the system.

Transaction Processing--- Part 1

Transaction processing systems are characterized by data base which is frequently being modified,perhaps several times a second.Typical applications are in airline seat-reservations and banking.In the former the data base contains information on seat availability,and is modified each time a seat is booked;in the latter it consists of details of accounts, which are updated for every credit and debit.

File Interrogation System---Part 2

………………of information on company performance,and medical information systems,in which the data base is a set of patients records.The user expects to be able to access information without any knowledge of how the database is organized,either in terms of software structures or hardware storage devices.Hence the os must make interrogation facilities available without involving the user in details of implementation.

Process Control

The term process control generally implies the control by computer of an industrial process such as the refining of oil or the manufacture of machine tools.It can be exended to include such things as environmental control in a space capsule or the monitoring of a patients condition in a hospital.The common features of all these applications is feedback;that is the computer receives input from the controlled process,computes a response which will maintain it stability and initates the mechanism for giving it.

File Interrogation System---Part 1

The distinguished feature of these systems is a large set of data,or data base,which can be interrogated for informations.The response to information requests must occur within a shorttime and data base must be capable of being modified as information is updated.Examples are management information systems,where the data base consist………………..

THE SUCCESS OF IPL

IPL (Indian premier league) Twenty- 20 cricket is coming to the end of the tournament with great success in the first time. In the words of Adam Gilchrist, "This is a tournament which will supposedly change the face of cricketing in the near future". Not only has this tournament provided loads of entertainment to cricket-crazy crowds in India, it has also exposed lots of hidden talents in the form of Shaun Marsh, Gony, Rohit Sharma and the like. These players have come into the limelight with their dazzling and fiery cricket. Players are awarded yearly contracts with huge paychecks and awesome bonuses. The tournament can be said to have attained 92% success and 8% failure considering the controversies which came out of it.

BLOOD IN PINK CITY

Jaipur on may 30th, due to the blast 60 people were killed and 200 injured .The bomb were place in several sites at the walled city area of Jaipur . The city cop were struggled with terror attack .It is fist forever in history of that city . Because of the blast riots were band by the police. But two days after the blast Hindu and Muslim communities were join together and arranged a meeting for the peace and fraternity.Hundreds of people were participated in that .It was held at the main square in the Walled City of Jaipur.