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magnetic resonance imaging

(Encyclopedia)magnetic resonance imaging (MRI), noninvasive diagnostic technique that uses nuclear magnetic resonance to produce cross-sectional images of organs and other internal body structures. The patient lies...

static

(Encyclopedia)static, term formerly use to describe electrical noise in radio reception, especially noise that originates outside a transmitter and receiver, e.g., in the atmosphere or in human-made devices. In gen...

direction finder

(Encyclopedia)direction finder, electronic device used to determine the position of a ship or aircraft. In a simple direction finder a radio receiver is equipped with a revolving directional antenna. The antenna re...

Rockefeller Center

(Encyclopedia)Rockefeller Center, complex of buildings in central Manhattan, New York City, between 48th and 51st streets and Fifth Ave. and the Ave. of the Americas (Sixth Ave.). The project was sponsored by John ...

Bloch, Felix

(Encyclopedia)Bloch, Felix, 1905–83, American physicist, b. Zürich, Switzerland, Ph.D. Univ. of Leipzig, Germany, 1928. He was a professor at Stanford from 1934 until his retirement in 1971. Bloch and Edward Pur...

Voice of America

(Encyclopedia)Voice of America, broadcasting service of the United States Information Agency, est. 1942. Originally set up as a means of fighting the cold war, the Voice of America produces and broadcasts radio pro...

dike, in technology

(Encyclopedia)dike, in technology: see levee.

Millennium Technology Prize

(Encyclopedia)Millennium Technology Prize, biennial award for innovations in technology, est. 2002 in Finland and bestowed by the Millennium Prize Foundation, an independent fund founded by members of Finnish indus...

brake, in technology

(Encyclopedia)CE5 Shoe brake CE5 Disk brake brake, in technology, device to slow or stop the motion of a mechanism or vehicle. The vacuum brake system, or vacuum brake, depends upon the use of a vacuum to ...