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Bikini

(Encyclopedia)Bikini bēkēˈnē [key], atoll, c.2 sq mi (5.2 sq km), W central Pacific, one of the Ralik Chain, Marshall Islands. It comprises 36 islets on a reef 25 mi (40 km) long. After its inhabitants were rem...

modulation, in communications

(Encyclopedia)CE5 Modulation modulation, in communications, process in which some characteristic of a wave (the carrier wave) is made to vary in accordance with an information-bearing signal wave (the modulatin...

Hawking, Stephen William

(Encyclopedia)Hawking, Stephen William, 1942–2018, British theoretical physicist, b. Oxford, England, grad. University College, Oxford, 1962, Ph.D. Trinity Hall, Cambridge, 1966. In 1962 Hawking was diagnosed as ...

nebula

(Encyclopedia)nebula nĕbˈyo͝olə [key] [Lat.,=mist], in astronomy, observed manifestation of a collection of highly rarefied gas and dust in interstellar space. Prior to the 1960s this term was also applied to b...

Jansky, Karl Guthe

(Encyclopedia)Jansky, Karl Guthe, 1905–50, American radio engineer; b. Norman, Okla. After graduating (1927) from the Univ. of Wisconson, he joined the Bell Telephone Laboratories. While trying to determine the c...

Cohen, Samuel Theodore

(Encyclopedia)Cohen, Samuel Theodore, 1921–2010, American physicist known as the “father of the neutron bomb,” b. Brooklyn, N.Y., grad. Univ. of California, Los Angeles, 1943. He worked on the Manhattan Proje...

Reber, Gröte

(Encyclopedia)Reber, Gröte, 1911–2002, American radio engineer, b. Chicago, Ill. After graduating from the Armour Institute of Technology (now the Illinois Institute of Technology) in 1933, Reber worked for seve...

CAT scan

(Encyclopedia)CAT scan kăt [key] [computerized axial tomography], X-ray technique that allows relatively safe, painless, and rapid diagnosis in previously inaccessible areas of the body; also called CT scan. An X-...

transformer

(Encyclopedia)transformer, electrical device used to transfer an alternating current or voltage from one electric circuit to another by means of electromagnetic induction. The simplest type of transformer consists ...

radio frequency

(Encyclopedia)radio frequency, range of electromagnetic waves with a frequency or wavelength suitable for communication uses. Some of these waves serve as carriers of the lower-frequency audio waves; others are mod...