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servomechanism

(Encyclopedia)servomechanism, automatic device for the control of a large power output by means of a small power input or for maintaining correct operating conditions in a mechanism. It is a type of feedback contro...

Sanger, Margaret Higgins

(Encyclopedia)Sanger, Margaret Higgins, 1879–1966, American leader in the birth control movement, b. Corning, N.Y. Personal experience and work as a public-health nurse, much of it on New York City's Lower East S...

Frederick II, Holy Roman emperor and German king

(Encyclopedia)Frederick II, 1194–1250, Holy Roman emperor (1220–50) and German king (1212–20), king of Sicily (1197–1250), and king of Jerusalem (1229–50), son of Holy Roman Emperor Henry VI and of Consta...

Ecclestone, Bernie

(Encyclopedia)Ecclestone, Bernie (Bernard Charles Ecclestone), 1930–, English automobile racing executive. After a short career racing Formula Three cars in the late 1940s and early 1950s, he managed Formula One ...

man, in anthropology and biology

(Encyclopedia)man: see anthropology; human evolution; race. ...

Geber, Arab alchemist and physician

(Encyclopedia)Geber: see Jabir.

Abu Musa

(Encyclopedia)Abu Musa, island (2010 est. pop. 1,868), c. 4.6 sq mi (12 sq km), E Persian Gulf, disputed between Iran, who occupies it, and the United Arab Emirates. Strategically located near the entra...

feedback

(Encyclopedia)CE5 Basic feedback control system feedback, arrangement for the automatic self-regulation of an electrical, mechanical, or biological system by returning part of its output as input. A simple exam...

Madrid, autonomous community and province, Spain

(Encyclopedia)Madrid mədrĭdˈ, Span. mäᵺhrēᵺˈ [key], autonomous community and coextensive prov., (2011 pop. 6,421,874), 3,099 sq mi (8,027 sq km), central Spain. Madrid, the capital of Spain, is also its c...

Titan , in Greek religion and mythology

(Encyclopedia)Titan, in Greek religion and mythology, one of 12 primeval deities. The female Titan is also called Titaness. The Titans—six sons and six daughters—were the children of Uranus and Gaea. They were ...