Electric Power Supplies: Devices that control the supply of electric current for running electrical equipment.Power Plants: Units that convert some other form of energy into electrical energy.Electric Wiring: An arrangement of wires distributing electricity.Electricity: The physical effects involving the presence of electric charges at rest and in motion.Electromagnetic Fields: Fields representing the joint interplay of electric and magnetic forces.Amplifiers, Electronic: Electronic devices that increase the magnitude of a signal's power level or current.Semiconductors: Materials that have a limited and usually variable electrical conductivity. They are particularly useful for the production of solid-state electronic devices.Equipment Design: Methods of creating machines and devices.Equipment Failure Analysis: The evaluation of incidents involving the loss of function of a device. These evaluations are used for a variety of purposes such as to determine the failure rates, the causes of failures, costs of failures, and the reliability and maintainability of devices.Transducers: Any device or element which converts an input signal into an output signal of a different form. Examples include the microphone, phonographic pickup, loudspeaker, barometer, photoelectric cell, automobile horn, doorbell, and underwater sound transducer. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)Electric Organ: In about 250 species of electric fishes, modified muscle fibers forming disklike multinucleate plates arranged in stacks like batteries in series and embedded in a gelatinous matrix. A large torpedo ray may have half a million plates. Muscles in different parts of the body may be modified, i.e., the trunk and tail in the electric eel, the hyobranchial apparatus in the electric ray, and extrinsic eye muscles in the stargazers. Powerful electric organs emit pulses in brief bursts several times a second. They serve to stun prey and ward off predators. A large torpedo ray can produce of shock of more than 200 volts, capable of stunning a human. (Storer et al., General Zoology, 6th ed, p672)Gymnotiformes: An order of neotropical electric fish found chiefly in the waters of South America. They continually emit weak electric discharges, which they use in object location and communication. A most popular species of research interest is the electric eel, ELECTROPHORUS electricus.Electric Stimulation: Use of electric potential or currents to elicit biological responses.Electric Injuries: Injuries caused by electric currents. The concept excludes electric burns (BURNS, ELECTRIC), but includes accidental electrocution and electric shock.