Page 56 - The Illustrated Dictionary of Electronics

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ARSR • assemble 41

ARSR Abbreviation of air route surveillance radar. those of the more bulky transmission line it re-
articulation A measure of the effectiveness of voice places in tests and measurements. It also serves
communications, expressed as the percentage of as a time-delay or phase-shift device and as a
speech units understood by the listener when the pulse-forming network.
effect of context is negligible. artificial voice A device used to test and calibrate
artificial antenna See DUMMY ANTENNA. noise-canceling microphones, consisting essen-
artificial ear A microphone-type sensor, equiva- tially of a small loudspeaker that has a baffle
lent to the human ear, used to measure sound whose acoustical properties simulate those of the
pressures. human head.
artificial echo 1. In radar practice, the reflections artos stripper A machine that cuts and strips wire
of a transmitted pulse returned by an artificial for the fabrication of multiconductor cables.
target. 2. A signal from a pulsed radio-frequency artwork 1. In the manufacture of printed circuits,
(RF) generator, delayed to simulate an echo. the scaled drawings from which the mask or etch
artificial ground The effective ground provided by pattern is obtained photographically. 2. Collec-
the radials or disk of a ground-plane antenna, as tively, the illustrations depicting an electronic cir-
opposed to actual ground (the earth itself). Com- cuit, device, or system.
pare TRUE GROUND. As Symbol for ARSENIC.
artificial horizon In aircraft instrumentation, a ASA Abbreviation of AMERICAN STANDARDS AS-
device that displays lines showing the position of SOCIATION.
the aircraft in flight, with reference to the hori- asbestos A nonflammable fibrous material consist-
zon. ing of calcium and magnesium silicates that is
artificial intelligence Abbreviation, AI. 1. A spe- used for high-temperature insulation.
cialized field of computer science overlapping A-scan A radar-screen presentation in which the
with electronics, biology, physiology, and other horizontal time axis displays distance or range,
sciences, concerning attempts to develop ad- and the vertical axis displays the amplitude of
vanced computer systems that can emulate the signal pulse and echo pulses.
processes of the human mind. 2. The ability of a ascending node For a satellite orbiting the earth or
computer to learn from its mistakes, refine its another planet, any point at which the ground-
own processes, and perhaps ultimately reason in track crosses the equator as it moves from the
a humanlike manner. southern hemisphere into the northern hemi-
artificial ionization An artificial reflecting layer sphere. This node generally changes for each
that is created in the atmosphere to provide a succeeding orbit, because the earth or planet ro-
skip condition. tates underneath the orbit of the satellite. Com-
artificial language A language that is not com- pare DESCENDING NODE.
monly used, but has been devised for efficiency in ascending pass For a specific point on the earth’s
a particular situation—especially in a computer surface, the time during which an artificial com-
system. munications satellite is accessible when its lati-
artificial life 1. The ultimate endpoint of ARTIFI- tude is moving northward. The duration of
CIAL INTELLIGENCE, wherein machines acquire accessibility depends on the altitude of the satel-
qualities, such as wisdom and the capability to lite, and on how close its groundtrack comes to
feel emotions. The state of the art is currently the earth-based point. Compare DESCENDING
nowhere near this point. 2. A hypothetical ma- PASS.
chine or set of machines with lifelike qualities, in- ASCII Acronym (pronounced “ask-ee”) for Ameri-
cluding human-level intelligence, wisdom, and can Standard Code for Information Interchange.
emotion. ASI Abbreviation for American Standards Institute.
artificial stimulus An electronic method of robot A-scope A radar system that displays an A-SCAN.
guidance and navigation using radar, sonar, vi- Askarel A synthetic, nonflammable liquid dielec-
sion systems, edge detection, and/or beacons. tric.
artificial transmission line A network of capaci- aspect ratio The width-to-height ratio of a video
tors and inductors with characteristics similar to image, generally three units high by four units
wide.
asperities On the surface of an electrode, tiny
points at which the electric field is intensified and
from which discharge is highly probable.
ASR 1. Abbreviation of AIRBORNE (or AIRPORT)
surveillance radar. 2. Abbreviation of AUTO-
MATIC SEND/ RECEIVE.
ASRA Acronym for automatic stereophonic record-
ing amplifier.
assemble 1. To gather subprograms into a com-
plete digital computer program. 2. To translate a