APPENDIX I
GLOSSARY
A
ACTIVE USW—A method for determining the
location and distance of a submarine by measuring
the time interval between the transmission of a
sound signal and its reflection back to the projector.
AEROSOLS—Small droplets (solid or liquid)
suspended in a gas.
AFMEDS—Air Force Meteorological Data System.
AFWA—Air Force Weather Agency headquartered at
Offutt AFB, NB.
AIG—Address indicator group.
ALGORITHM—A step-by-step procedure for solving
a mathematical problem.
ANALOG—Proportional and continuous. An analog
recorder draws continuous lines proportional to the
electronic signal input.
AOR—Area of responsibility.
APT—Automatic picture transmission. The automatic
transmission of images by polar-orbiting satellites.
ARQ—Automatic response to query. A method of
obtaining data using AFMEDS.
ASOS—Automated surface observing system.
AUTODIN—Automatic digital network:
AWN—Automated weather network; the complex
worldwide collection and distribution network of
meteorological data operated by the Air Force.
AZIMUTH—The horizontal angular measurement
from a fixed reference to a point. The navy uses
angular measurements in clockwise degrees from 0
to 360. When 0 is referenced to true north, the result
is a true azimuth bearing. When referenced to an
arbitrary direction, such as the bow of a ship, the
result is a relative azimuth bearing.
B
BATHYTHERMOGRAPH—Any device used to
measure and record temperatures through a column
of water.
BAUD—A measurement unit of electronic data
transmission speed.
BT—Abbreviation for break transmission, used to
indicate the beginning and end of a message body.
BULLETIN BOARD—A communications system
that uses standard telephone lines to dial-in and
access computer networks.
BYTE—A group of adjacent binary digits (bits).
C
CAD—Collective address designator.
CCTV—Closed-circuit television.
CHAFF—Material (such as strips of foil) ejected into
the air in order to confuse enemy radar devices.
COMSEC—Communications security.
CONFIDENTIAL—Classified information that if
disclosed could be expected to cause damage to
national security.
COTS—Commercial-off-the-shelf.
CPU—Central processing unit of a computer.
CW—Continuous wave radio transmission.
D
DATA BASE—A collection of data organized for
rapid search and retrieval by a computer.
DIFAX—Digital facsimile.
DMSP—Defense meteorological satellite program.
DPVS—Distributed plain language verification
system.
DSN—Defense switched network, an upgrade and
name change to the automatic voice network
(AUTOVON).
DUCT—A layer in the atmosphere that readily traps
electromagnetic energy permitting extended
transmission ranges.
DUCTING—The process occurring within a duct, also
known as trapping.
AI-1
