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Poulsen, Valdemar

(Encyclopedia)Poulsen, Valdemar välˈdəmär poulˈsən [key], 1869–1942, Danish electrical engineer. He invented (1898) the telegraphone (an early wire recorder) and the high-frequency Poulsen arc used in wirel...

noise

(Encyclopedia)noise, any signal that does not convey useful information. Electrical noise consists of electrical currents or voltages that interfere with the operation of electronic systems. Electrical noise limits...

European Launcher Development Organization

(Encyclopedia)European Launcher Development Organization (ELDO): see European Space Agency. ...

Agency for International Development

(Encyclopedia)Agency for International Development (AID), federal agency created (Sept., 1961) to consolidate U.S. nonmilitary foreign aid programs. Originally an agency in the State Department, it has been a compo...

United Nations Development Program

(Encyclopedia)United Nations Development Program (UNDP), agency of the United Nations, established in 1965 to unify the operations of the Expanded Program of Technical Assistance and the United Nations Special Fund...

Oberlin, Russell Keys

(Encyclopedia)Oberlin, Russell Keys, 1928–2016, American countertenor, b. Akron, Ohio, grad. Juilliard, 1951. A boy soprano, he sang in his church choir and on the radio, and won a nationwide radio talent competi...

barcode

(Encyclopedia)CE5 Barcode barcode, computer coding system that uses a printed pattern of lines and bars to identify such things as products, mail and packages, and customer accounts; the term also is used for s...

Levallois-Perret

(Encyclopedia)Levallois-Perret ləvälwäˈ-pĕrāˈ [key], residential and industrial suburb of Paris (1990 pop. 47,788), Hauts-de-Seine dept., N central France, on the Seine River. Automobiles, electrical and rad...

Penticton

(Encyclopedia)Penticton, city (1991 pop. 27,258), S British Columbia, Canada, located where the Okanagan River flows into Okanagan Lake. It is a service and trade center for the Okanagan valley, a resort and fruit-...

satellite, artificial

(Encyclopedia)CE5 A. Nimbus weather satellite B. Syncom communications satellite satellite, artificial, object constructed by humans and placed in orbit around the earth or other celestial body (see also space ...