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grinding

(Encyclopedia)grinding, process by which surface material is removed from an object, usually metal, by the abrasive action of a rotating wheel or a moving belt that contains abrasive grains. A grinding wheel can be...

fetish

(Encyclopedia)fetish fĕtˈĭsh [key], inanimate object believed to possess some magical power. The fetish may be a natural thing, such as a stone, a feather, a shell, or the claw of an animal, or it may be artific...

Doolittle, James Harold

(Encyclopedia)Doolittle, James Harold, 1896–1993, American aviator, b. Alameda, Calif. After serving in World War I as a flier he returned to school and earned a Sc.D. from MIT. He then became noted for his speed...

serval

(Encyclopedia)serval, medium-sized African cat, Leptailurus serval, found S of the Sahara in scrub country close to water. The serval is lightly built with very long legs; it has a small head with large eyes and ea...

Rickenbacker, Edward Vernon

(Encyclopedia)Rickenbacker, Edward Vernon, 1890–1973, American war hero and airline executive, b. Columbus, Ohio. He became a car racing driver at 16 and set numerous speed records. In World War I he volunteered ...

matrix

(Encyclopedia)matrix, in mathematics, a rectangular array of elements (e.g., numbers) considered as a single entity. A matrix is distinguished by the number of rows and columns it contains. The matrix CE5 is a 2...

Treisman, Anne

(Encyclopedia)Treisman, Anne, 1935–2018, British cognitive psychologist, b. Anne Marie Taylor, Ph.D. Oxford, 1962. She taught at Oxford from 1968, the Univ. of British Columbia from 1978, Univ. of California, Ber...

radar

(Encyclopedia)radar, system or technique for detecting the position, movement, and nature of a remote object by means of radio waves reflected from its surface. Although most radar units use microwave frequencies, ...

Serbia and Montenegro

(Encyclopedia)CE5 CE5 Serbia and Montenegro mŏnˌtənēˈgrō [key], Serbian Srbija i Crna Gora, former country of SE Europe, in the Balkan Peninsula, a short-lived union (2003–6) of the republics of Serbia...

determinant

(Encyclopedia)determinant, a polynomial expression that is inherent in the entries of a square matrix. The size n of the square matrix, as determined from the number of entries in any row or column, is called the o...