18WuD2x

neper • network analog 473
on common logarithms, in the following manner:
1 Np = 8.686 dB; 1 dB = 0.1151 Np.
neptunium Symbol, Np. A radioactive metallic element
produced artificially. Atomic number, 93.
Atomic weight, 237.05.
Nernst effect The appearance of a voltage between
the opposite edges of a metal strip that is conducting
heat longitudinally when the strip is
placed in a magnetic field perpendicular to the
plane of the strip.
Heated
metal
strip
B field
90°
Nernst effect
Nernst-Ettinghausen effect In a piezoelectric crystal,
the tendency for a temperature gradient to exist
as a result of applied electromagnetic fields.
Nernst lamp An incandescent lamp in which the
filament material is a mixture of magnesia and
certain rare oxides (such as yttria). A surrounding
current-carrying coil heats the filament, lowering
its resistance and causing it to glow, after
which it continues to operate on a low current.
nerve center The most essential part of a control
system or communication network.
nerve current In an animal organism, the small
electrical current that flows along nerve fibers.
nervous breakdown The upset of a function in a digital
computer (which becomes disabled as a result).
NESC Abbreviation of National Electrical Safety
Code.
nested loops See NESTING.
nesting In digital computers and data processing,
the inclusion of one or more loops or subroutines
inside a larger loop or subroutine. Nested loops,
for example, can be used to assign values to
double-subscripted variables.
NET Abbreviation of noise equivalent temperature.
net 1. An effective, useful, or resultant quantity
(e.g., NET CAPACITANCE). 2. Colloquialism for
communications network. See NETWORK, 2.
net authentification A password or other special
identification used in a radio network.
net capacitance The resultant capacitance in a
circuit in which capacitances act in combination
with each other.
net component The total value of two or more passive
components of the same sort. See, for example,
NET CAPACITANCE, NET CURRENT, NET
IMPEDANCE, NET INDUCTANCE, NET POWER,
NET REACTANCE, NET RESISTANCE, and NET
VOLTAGE.
net current The current flowing in a circuit in
which currents aid or oppose each other.
net gain For an amplifier, the amount of gain remaining
after all losses in the device have been
subtracted.
net impedance The impedance of a circuit in
which impedances act in combination with each
other.
net inductance The inductance of a circuit in which
inductances act in combination with each other.
net loss For an amplifier or other system, the algebraic
sum of gains and losses between two points
in the system.
net power The resultant power observed when
power signals aid or oppose each other in a single
circuit or system.
net radiometer A device for measuring the difference
in intensity between radiation entering the
earth’s surface and radiation leaving it. This is
generally visible light or infrared radiation from
the sun.
net reactance Symbol, X t . The combined inductive
reactance (X L ) and capacitive reactance (X C ) in a
circuit or device.
net resistance The resistance of a circuit in which
resistances act in combination with each other.
net voltage The resultant voltage at a point where
voltages aid or oppose each other.
network 1. A circuit arrangement of electronic
components, sometimes redundant in its design
[e.g., resistance-capacitance (RC) network]. 2. A
group of interconnected computers, communications
stations, or other facilities, often organized
for simultaneous operation and data transfer.
3. To conduct research or gather information
using a group of interconnected computers,
communications stations, or other facilities.
network analog A circuit or circuits representing
variables and used to express and solve a mathematical
relationship between the variables.