pulses per second
81information theory — the mathematical theory concerned with the content, transmission, storage, and retrieval of information, usually in the form of messages or data, and esp. by means of computers. [1945 50] * * * ▪ mathematics Introduction a mathematical… …
82particle accelerator — accelerator (def. 7). [1945 50] * * * Device that accelerates a beam of fast moving, electrically charged atoms (ions) or subatomic particles. Accelerators are used to study the structure of atomic nuclei (see atom) and the nature of subatomic… …
83thunderstorm — /thun deuhr stawrm /, n. a transient storm of lightning and thunder, usually with rain and gusty winds, sometimes with hail or snow, produced by cumulonimbus clouds. Also called electrical storm. [1645 55; THUNDER + STORM] * * * Violent, short… …
84Soliton (optics) — In optics, the term soliton is used to refer to any optical field that does not change during propagation because of a delicate balance between nonlinear and linear effects in the medium. There are two main kinds of solitons: spatial solitons:… …
85ENIAC — [ Betty Jean Jennings (left) and Fran Bilas (right) operate the ENIAC s main control panel at the Moore School of Electrical Engineering. (U.S. Army photo from the archives of the ARL Technical Library)] ENIAC, short for Electronic Numerical… …
86nebula — nebular, adj. /neb yeuh leuh/, n., pl. nebulae / lee , luy /, nebulas. 1. Astron. a. Also called diffuse nebula. a cloud of interstellar gas and dust. Cf. dark nebula, emission nebula, reflection nebula …
87Crab Nebula — Crab Nebula …
88Fire alarm notification appliance — A Wheelock MT 24 LSM electronic fire alarm horn and strobe. A fire alarm notification appliance is an active fire protection component. A notification appliance may use audible, visible, or other stimuli to alert the occupants of a fire or other… …
89laser — /lay zeuhr/, n. Physics. a device that produces a nearly parallel, nearly monochromatic, and coherent beam of light by exciting atoms to a higher energy level and causing them to radiate their energy in phase. Also called optical maser. [1955 60; …
90amorphous solid — ▪ physics Introduction any noncrystalline solid in which the atoms and molecules are not organized in a definite lattice pattern. Such solids include glass, plastic, and gel. Solids and liquids (liquid) are both forms of condensed… …
