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Turbocharger:

The purpose of supercharging is to increase the mass of air trapped in the cylinder of the engine, by raising air density. This allows more fuel to be burnt, inreasing the power output of the engine, for a given swept volume of the cylinders. Thus the power to weight and volume ratios of the engine increase. Since more fuel is burnt to achieve the power increase, the efficiency of the engine cycle remains unchanged. A compressor is used to achieve the increase in the air density. Two methods of supercharging can be distingused by the method to drive the compressor. If the compressor is driven form the crankshaft of the engine, the system is called "mechanically driven supercharging" or often just" supercharging". If the compressor i driven by a turbine, which itself driven by exhaust gas from the cylinders, the system is called "turbocharging". The shaft of the turbocharger links the compressor and turbine, but is not connected to the crankshaft of the engine. Thus the power developed by the turbine dictates the compressor operating point, since it must equal that absorbed by the compessor.

(Diesel engine reference book, Second edition, p. 29-Edited by Bernard Challen and Rodice Baranescu)

SI Engine:

The spark- ignition engine (or SI Engine) is a piston engine with external or internal air-mixture formation. External mixture formation generally produces homogenous mixtures, whereas an internally formed mixture is largely heterogenos at the instant of ignition. The time of the mixture formation is a major factor influencing the degree of homogenization achievable by internal mixture formation. In both cases, the mixture is compressed to approximately 20-30 bar on the compression stroke, to generate a final compression temperature of 400-500C. This is still below teh auto-ignition threshold of the mixture, which then has to be ignited by a spark shorly before te piston reaches TDC.

(Bosch automotive handbook,Section;Reciprocating- piston engines with internal combustion, p.8)

CI Engine:

The compression ignition (CI) engine operates with a heterogeneous charge of previously compressed air and finely divided spray of liquid fuel. The latter is injected into the engine cylinder towards the end of the compressor when, after a suitably intensive mixing process with the air already in the cylinder, the self ignition properties of the fuel cause combustion to be initiated frm small nuclei . These spread rapidly so that complete combustion of all injected fuel, usually with the air- fuel ratios well in excess of stoichiometric, is ensured. The mixing process is crucial to the operation of the Diesel engine and as such has received a great deal of the attention which is reflected in a wide variety of combustion systems which may conveniently be grouped in two broad categories, viz.
a) Direct Injection (DI) Systems as used in DI engines
b) Indirect Injection (IDI) Systems as used in IDI engines

(Diesel engine reference book, Second edition, p. 5- Edited by Bernard Challen and Rodice Baranescu)

LAN:

A network is a linking of a group of computers to communicate with each other and share software and hardware recources via the cables and interfaces that connect the computers and peripherals. Application software used in a network allow several users access the same program and data at the same time. As the name implies, a Local Area Network or LAN is a system that covers short distances. Usually LAN is limited to a single department or a single building or a single campus. Typical data tranmission speeds are one to 100 megabits per second.

(P. Radhakrishan, S. Subramanyan, V. Raju, CAD/CAM/CIM, Second edition, p.526)