Page 124 - Electrical Engineering Dictionary

switchsuchthatthedataistransferredinunits thesumofthemaximumdataratesthatcanbe
of a fixed size. delivered to subscribers affiliated to all base
stations in a re-use cluster of cells, occupying
cell-cycle-specific control a type of con- as small a physical area as possible. Mathe-
trol arising in scheduling optimal treatment matically, the cellular spectral efficiency, η,
protocols in the case when treated popula- is defined as
tion is sensitive to the therapy only in cho-
sen phases of its cell cycle. A mathematical
P r P K
model of population dynamics used to solve
j=1 i=1 R ij 2
the problem of such control should be com- η = bit/s/Hz/km
BA cluster
posed of subsystems sensitive and insensitive
where r denotes the number of cells in a re-
to the drug. It may be achieved by the use
use cluster, R ij denotes the data rate mea-
of compartmental models. Typical types of
perturbations of the cell cycle considered as sured in bits/s at some predefined BER avail-
cel-cycle-specific control are as follows: cell able to subscriber I in cell j of the re-use
arrest, cell killing, and alteration of the transit cluster, B denotes the total bandwidth mea-
time. They could be applied for representa- sured in hertz allocated to all cells in the re-
tion of cell synchronization, cell destruction, use cluster, and A cluster denotes the physical
and cell recruitment from the specific phase. area, measuredinsquarekilometersoccupied
by the re-use cluster.
cellular automaton system designed
from many discrete cells, usually assem- CELP See code excited linear prediction.
bled in one- or two-dimensional regular ar-
rays, each of which is a standard finite
state machine. Each cell may change its center frequency (1) the frequency of
maximum or minimum response for a band-
state only at fixed, regular intervals, and
pass or a bandstop filter, respectively; often
only in accordance with fixed rules that de-
taken as the geometric mean of the lower and
pend on cells’ own values and the values of
upper cutoff frequencies.
neighbors within a certain proximity (usually
two- for one-dimensional, and four- for two- (2) the frequency at the center of a spec-
dimensional cellular automata). Cellular au- trum display.
tomata are a base of cellular computers; fine (3) the average frequency of the emitted
grain systems that are usually data-driven and wave after modulation by a sinusoidal signal.
used to implement neural networks, systolic (4) the frequency of a non-modulated
arrays, and SIMD architectures. wave. See also channel.

cellular communications traditionally, centerofaverage anapproachofdefuzzi-
an outside-of-building radio telephone sys- fication that takes the weighted average of the
tem that allows users to communicate from centers of fuzzy sets with the weights equal
their car or from their portable telephone. to the firing strengths of the corresponding
fuzzy sets.
cellular manufacturing grouping of
parts by design and/or processing similarities center of gravity method See centroid
such that the group (family) is manufactured method.
on a subset of machines which constitute a
cell necessary for the group’s production. center of projection the point within a
projector from which all the light rays ap-
cellular spectral efficiency the cellular pear to diverge; the point in a camera toward
spectral efficiency of a system is defined as which all the light rays appear to converge

c
2000 by CRC Press LLC