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Shannon, Claude Elwood

(Encyclopedia)Shannon, Claude Elwood, 1916–2001, American applied mathematician, b. Gaylord, Michigan. A student of Vannevar Bush at the Massachusetts Institute of Technology (MIT), he was the first to propose th...

Port Said

(Encyclopedia)Port Said bo͝or [key], city (1986 pop. 469,533), NE Egypt, a port on the Mediterranean Sea at the entrance to the Suez Canal. It is a fueling point for ships using the canal and is the site of the ma...

plastic surgery

(Encyclopedia)plastic surgery, surgical repair of congenital or acquired deformities and the restoration of contour to improve the appearance and function of tissue defects. Development of this specialized branch o...

pi

(Encyclopedia)pi, in mathematics, the ratio of the circumference of a circle to its diameter. The symbol for pi is π. The ratio is the same for all circles and is approximately 3.1416. It is of great importance in...

Newcomb, Simon

(Encyclopedia)Newcomb, Simon no͞oˈkəm, nyo͞oˈ– [key], 1835–1909, American astronomer, b. Nova Scotia, grad. Lawrence Scientific School, Harvard, 1858. Living in the United States from 1853, he was appointe...

Sacramento, city, United States

(Encyclopedia)Sacramento săkrəmĕnˈtō [key], city (1990 pop. 369,365), state capital and seat of Sacramento co., central Calif., on the Sacramento River at its confluence with the American River; settled 1839, ...

wind tunnel

(Encyclopedia)wind tunnel, apparatus for studying the interaction between a solid body and an airstream. A wind tunnel simulates the conditions of an aircraft in flight by causing a high-speed stream of air to flow...

xerography

(Encyclopedia)xerography zərŏgˈrəfēˌ [key], also called electrophotography, method of dry photocopying in which the image is transferred by using the attractive forces of electric charges. A beam of light, us...

spark chamber

(Encyclopedia)spark chamber, in physics, device for recording the passage of elementary particles produced by reactions in a particle accelerator. Particles pass through a stack of metal plates or wire grids that a...

Boolean algebra

(Encyclopedia)Boolean algebra bo͞oˈlēən [key], an abstract mathematical system primarily used in computer science and in expressing the relationships between sets (groups of objects or concepts). The notational...