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control systems

(Encyclopedia)control systems, combinations of components (electrical, mechanical, thermal, or hydraulic) that act together to maintain actual system performance close to a desired set of performance specifications...

rent control

(Encyclopedia)rent control, in economics and law, government regulation of rent to prevent unreasonable or excessive increases. In the United States, the federal government imposed rent control (and other price con...

birth control

(Encyclopedia)birth control, practice of contraception for the purpose of limiting reproduction. Although contraceptive techniques had been known in ancient Egypt, Greece, and Rome, the modern movement for birth ...

gun control

(Encyclopedia)gun control, government limitation of the purchase and ownership of firearms. The availability of guns is controlled by nations and localities throughout the world. In the United States the “right o...

control surface

(Encyclopedia)control surface: see airfoil.

numerical control

(Encyclopedia)numerical control: see computer-aided manufacturing. ...

Centers for Disease Control and Prevention

(Encyclopedia)Centers for Disease Control and Prevention (CDC), agency of the U.S. Public Health Service since 1973, with headquarters in Atlanta; it was established in 1946 as the Communicable Disease Center. The ...

air traffic control

(Encyclopedia)air traffic control, the system by which airplanes are safely routed into and out of major airports. Air traffic control in the United States is centered in a number of regional control centers that r...

automatic frequency control

(Encyclopedia)automatic frequency control: see automatic tuning control. ...

automatic tuning control

(Encyclopedia)automatic tuning control (ATC), method or device to keep a radio or television receiver automatically tuned to a desired frequency or channel. Assuming that the receiver is at least approximately tune...