Channel Encoding
As described in Source encoding, one purpose of the source encoder is to eliminate redundant binary digits from the digitized signal. The strategy of the channel encoder, on the other hand, is to…
Telecommunication
Telecommunication, science and practice of transmitting information by electromagnetic means. Modern telecommunication centres on the problems involved in transmitting large volumes of information over long distances without damaging loss due to noise…
Other methods of machining
Ultrasonic machining (USM) In USM, material is removed from a workpiece with particles of abrasive that vibrate at high frequency in a water slurry circulating through a narrow gap between a vibrating…
Electrical-discharge machining (EDM)
EDM involves the direction of high-frequency electrical spark discharges from a graphite or soft metal tool, which serves as an electrode, to disintegrate electrically conductive materials such as hardened steel or…
Adaptive control
Improvements in CNC machine tools depend on the refinement of adaptive control, which is the automatic monitoring and adjustment of machining conditions in response to variations in operation performance. With a manually…
Frequency response
Hearing aid Hearing aid, device that increases the loudness of sounds in the ear of the wearer. The earliest aid was the ear trumpet, characterized by a large mouth at one end…
Damping
Damping, in physics, restraining of vibratory motion, such as mechanical oscillations, noise, and alternating electric currents, by dissipation of energy. Unless a child keeps pumping a swing, its motion dies down because of damping. Shock absorbers…
Servomechanism
Servomechanism, automatic device used to correct the performance of a mechanism by means of an error-sensing feedback. The term servomechanism properly applies only to systems in which the feedback and…
Superconductivity
Superconductivity, complete disappearance of electrical resistance in various solids when they are cooled below a characteristic temperature. This temperature, called the transition temperature, varies for different materials but generally is below 20 K (−253 °C).…
Electromotive force
Electromotive force, abbreviation E or emf, energy per unit electric charge that is imparted by an energy source, such as an electric generator or a battery. Energy is converted from one form to another in the generator or battery as…
