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analog-to-digital conversion

(Encyclopedia)analog-to-digital or A/D conversion, the process of changing continuously varying data, such as voltage, current, or shaft rotation, into discrete digital quantities that represent the magnitude of th...

bark cloth

(Encyclopedia)bark cloth, primitive fabric made in tropical and subtropical countries from the soft inner bark of certain trees. It has been made and used in parts of Africa and India, the Malay Peninsula, Samoa, t...

dandruff

(Encyclopedia)dandruff, excessive flaking of skin from the scalp, apparent as dry or greasy diffuse scaling with variable itching. It is the sign of a skin disease, such as seborrhea or a fungal infection. Treatmen...

breast cancer

(Encyclopedia)breast cancer, cancer that originates in the breast. Breast cancer is the second leading cause of cancer death in women (following lung cancer). Although the vast majority of the cases occur in women,...

conjunctivitis

(Encyclopedia)conjunctivitis kənjəngtəvīˈtəs [key], inflammation or infection of the mucosal membrane that covers the eyeball and lines the eyelid, usually acute, caused by a virus or, less often, by a bacill...

angle

(Encyclopedia)angle, in mathematics, figure formed by the intersection of two straight lines; the lines are called the sides of the angle and their point of intersection the vertex of the angle. Angles are commonly...

sodium silicate

(Encyclopedia)sodium silicate, any one of several compounds containing sodium oxide, Na2O, and silica, Si2O, or a mixture of sodium silicates. Sodium orthosilicate is Na4SiO4 (or 2Na2O·SiO2); sodium metasilicate i...

centering

(Encyclopedia)centering, the framework of wood or of wood and steel built to support a masonry arch or vault during its construction. The centering itself must be rigidly supported, either by posts from the ground ...

coal mining

(Encyclopedia)coal mining, physical extraction of coal resources to yield coal; also, the business of exploring for, developing, mining, and transporting coal in any form. Coal has been historically important indus...

bearing

(Encyclopedia)bearing, machine part designed to reduce friction between moving parts or to support moving loads. There are two main kinds of bearings: the antifriction type, such as the roller bearing and the ball ...