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distortion

(Encyclopedia)distortion, in electronics, undesired change in an electric signal waveform as it passes from the input to the output of some system or device. In an audio system, distortion results in poor reproduct...

child labor

(Encyclopedia)child labor, use of the young as workers in factories, farms, mines, and other facilities, especially in work that is physically hazardous or morally, socially, or mentally harmful, involves a form of...

civil service

(Encyclopedia)civil service, entire body of those employed in the civil administration as distinct from the military and excluding elected officials. The term was used in designating the British administration of I...

alkene

(Encyclopedia)CE5 Alkenes alkene ălˈkēn [key], any of a group of aliphatic hydrocarbons whose molecules contain one or more carbon-carbon double bonds (see chemical bond). Alkenes with only one double bond h...

Great Lakes, lakes and region, E Africa

(Encyclopedia)Great Lakes, group of freshwater lakes lying along the Great Rift Valley, E Africa, including Lakes Victoria, Tanganyika, Nyasa, Turkana, Albert, Kivu, and Edward. Lakes Victoria, Albert, and Edward e...

Fox Quesada, Vicente

(Encyclopedia)Fox Quesada, Vicente vēsānˈtā fōks kāsäˈᵺä [key], 1942–, Mexican political leader, president of Mexico (2000–6). Raised on a ranch in rural central Mexico's Guanajuato state, he became ...

alkyne

(Encyclopedia)CE5 Alkynes alkyne ălˈkīn [key], any of a group of aliphatic hydrocarbons whose molecules contain one or more carbon-carbon triple bonds (see chemical bond). Alkynes with one triple bond have t...

neurology

(Encyclopedia)neurology no͝orŏlˈəjē, nyo͝o– [key], study of the morphology, physiology, and pathology of the human nervous system. As researchers, neurologists carry on investigative and experimental work i...

Goldmark, Peter Carl

(Encyclopedia)Goldmark, Peter Carl, 1906–77, Hungarian-American engineer, b. Budapest. He studied at the Univ. of Vienna (B.S., 1929, Ph.D., 1931); worked for a radio company in England (1931–33). After emigrat...

electric and magnetic units

(Encyclopedia)electric and magnetic units, units used to express the magnitudes of various quantities in electricity and magnetism. Three systems of such units, all based on the metric system, are commonly used. On...