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operational amplifier

(Encyclopedia)operational amplifier, amplifier whose output voltage is proportional to the negative of its input voltage and that boosts the amplitude of an input signal many times, i.e., has a very high gain. It i...

3D printer

(Encyclopedia)3D printer, computerized device that produces a three-dimensional object by creating it as a series of thin layers. The object is created from a model stored in computer-aided design file; the model i...

catalog

(Encyclopedia)catalog, descriptive list, on cards or in a book, of the contents of a library. Assurbanipal's library at Nineveh was cataloged on shelves of slate. The first known subject catalog was compiled by Cal...

supercomputer

(Encyclopedia)supercomputer, a state-of-the-art, extremely powerful computer capable of manipulating massive amounts of data in a relatively short time. Supercomputers are very expensive and are employed for specia...

McGill University

(Encyclopedia)McGill University, at Montreal, Que., Canada; coeducational; chartered 1821, opened 1829. It was named for James McGill, who left a bequest to establish it. Its real development dates from 1855 when J...

graph

(Encyclopedia)graph, figure that shows relationships between quantities. The graph of a function y=f (x) is the set of points with coordinates [x, f (x)] in the xy-plane, when x and y are numbers. A similar definit...

Andover

(Encyclopedia)Andover ănˈdōvər [key], town (2020 pop. 36,569), Essex co., NE Mass.; inc. 1646. Chiefly a textile producer in the 19th cent., Andover now makes toiletries, electronic...

flight simulator

(Encyclopedia)flight simulator, device providing a controlled environment in which a flight trainee can experience conditions approximating those of actual flight. A simulator generally consists of an enclosure hou...

Hounsfield, Sir Godfrey Newbold

(Encyclopedia)Hounsfield, Sir Godfrey Newbold, 1919–2004, British electrical engineer. A radar expert for the Royal Air Force during World War II, in the 1950s Hounsfield began developing computer and X-ray techn...

Howard Hughes Medical Institute

(Encyclopedia)Howard Hughes Medical Institute, (HHMI), nonprofit medical research organization founded in 1953 by Howard Hughes and largly funded from proceeds of the 1984–85 sale of Hughes Aircraft. Headquartere...