18WuD2x

iofeedback monitor • Birmingham wire gauge 75
ness, anger, etc., these monitors might be of
value to people who wish to gain improved control
of their emotions, and thus perhaps minimize the
physiological effects of stress.
biological robot Believed by some researchers to
be possible, but not yet a practical reality: A living
organism created by biological cloning, whose
brain has been programmed exactly as a computer
is programmed.
biological shield An absorbent shield that blocks
or attenuates ionizing radiation to protect personnel
working near radioactive materials.
bioluminescence 1. The emission of light by a living
organism. 2. The light itself so produced by
living organisms.
biomechanism An electromechanical device that
simulates the workings of some part of a living
being’s body. Examples are electromechanical
hands, arms, and legs. Such a device is often difficult
to distinguish from its biological counterpart
when obscured by clothing.
biomechatronics A contraction of the words biology,
mechanics and electronics. Research, development
and manufacturing that encompasses
aspects of all three fields. This is especially important
in robotics.
biometrics Mathematics, and in particular, statistics
and probability, applied to biology.
biometric security system An advanced intrusion-prevention
system that measures biological
characteristics of the people who are authorized
to enter a property. Such a machine can employ
vision systems, object recognition, and/or pattern
recognition to check a person’s face. The machine
might use speech recognition to identify
people by the waveforms of their voices. It might
record a hand print, a fingerprint, or an iris print,
or a combination of all these things. A powerful
computer analyzes the data obtained by the sensors
and determines whether the person is authorized
to enter the premises.
bionics The study, design, and application of microelectronic
systems that simulate the functions
of living organisms.
biotelemetry The use of telemetry to collect data
from living organisms or to direct their movement.
biotelescanner An instrument that monitors body
functions via radio, from a great distance.
Biot/Savart law A principle of electromagnetism
that expresses the intensity of magnetic field H in
the vicinity of a long, straight wire carrying a
steady current I. The basic formula is H = 2I/r,
where H is in oersteds, I is in amperes, and r is
the distance in centimeters from the wire.
bip Abbreviation of binary image processor.
biphase half-wave rectifier An alternative term
for FULL-WAVE RECTIFIER; also, each leg of a
two-diode full-wave rectifier.
BIPM Abbreviation of International Bureau of
Weights and Measures.
bipolar The condition of possessing two pole sets. In
a conventional (non-FET) transistor, one pole set
exists between the base and collector, and another
pole set exists between the base and emitter.
bipolar driving unit A magnetic headphone or
loudspeaker in which both poles (north and
south) of a magnet actuate a diaphragm or lever.
bipolar operation See AUTOMATIC POLARITY.
bipolar transistor A two-junction transistor whose
construction takes the form of a pnp or an npn
“sandwich.” Such devices are current-operated,
compared with field-effect transistors, which are
voltage-operated. The bipolar transistor (of which
the familiar npn and pnp types are examples)
uses both electron and hole conduction.
biquinary code A variety of binary-coded-decimal
notation in which seven bits are used to represent
each decimal digit. A number is written in
two groups of bits: a two-bit group followed by a
five-bit group. The positional values are 5 and 0
for the two-bit group, and 4, 3, 2, 1, and 0 for the
five-bit group.
biquinary decade A decade counter that consists
of a binary stage, followed by a quinary stage.
bird 1. Slang for orbiting SATELLITE. 2. Slang for
guided missile.
birdie 1. A spurious beat note in a superheterodyne
receiver. So called because of the characteristic
chirping sound it makes as the operator
tunes by the frequency on which it occurs. 2. A
parasitic oscillation in a radio transmitter, also
called a spurious emission or spur.
Birmingham wire gauge Abbreviation, BWG. Also
called Stubs gauge. A method of designating the
various sizes of solid wire. BWG diameters are
somewhat larger than corresponding AMERICAN
WIRE GAUGE diameters for a given wire-size
designator.
Birmingham Wire Gauge (BWG) Diameters
BWG Millimeters Inches
1 7.62 0.300
2 7.21 0.284
3 6.58 0.259
4 6.05 0.238
5 5.59 0.220
6 5.16 0.203
7 4.57 0.180
8 4.19 0.165
9 3.76 0.148
10 3.40 0.134
11 3.05 0.120
12 2.77 0.109
13 2.41 0.095
14 2.11 0.083
15 1.83 0.072
16 1.65 0.064
17 1.47 0.058
18 1.25 0.049
19 1.07 0.042
20 0.889 0.035