Partial discharge Partial discharge In electrical engineering, partial discharge (PD) is a localized dielectric breakdown (DB) of a small portion of a solid or fluid electrical insulation (EI) system under high voltage (HV) stress, which does not bridge the space between two conductors. While a corona discharge (CD) is usually revealed by a relatively steady glow or brush discharge (BD) in air, partial discharges within solid insulation system are not visible. PD can occur in a gaseous, liquid or solid insulating medium. It often starts within gas voids, such as voids in solid epoxy insulation or bubbles in transformer oil. Protracted partial
Echo word Echo word Echo word is a linguistic term that refers to a particular kind of reduplication which is a widespread areal feature in the languages of South Asia. Echo words are characterized by reduplication of a complete word or phrase, with the initial segment or syllable of the reduplicant being overwritten by a fixed segment or syllable. In most languages in which this phenomenon is present, echo words serve to express a meaning of "... and such; and things like that." In some cases the echo word may express a depreciative meaning as well. Echo word usage is almost exclusively