Page 116 - Electrical Engineering Dictionary

CAMAC acronym for computer auto- candlepower distribution a curve, gen-
mated monitor and control — an internation- erally polar, representing the variation of lu-
ally accepted set of standards for electronic minous intensity of a lamp or luminaire in a
instrumentation, which specifies mechanical, plane through the light center.
electrical, and functional characteristics of
the instrument modules. canned magnet a magnet that is com-
pletely encased in its own vacuum jacket.
camera a device for acquiring an image,
usually in a photographic or electronic form Canny edge detector an edge detector
— in the latter case typically as a TV camera. that uses an approximation to the optimal fil-
Cameras may operate in optical, infra red, or ter. Seeinfinitesymmetricexponentialfilter.
other wavelength bands.
Canny operator an edge detector devised
by John Canny as the optimal solution to a
camera calibration a process in which
variational problem with three constraints.
certain camera parameters, or equivalently
The general solution obtained numerically
some quantities that are required for determi-
can be approximated in practical contexts by
nation of the perspective projection on an im-
the first derivative of a Gaussian. Canny op-
age plane of a point in the 3-D world, are cal-
erator usually refers to the extension to two
culated by using the known correspondence
dimensions of this approximation, i.e., to use
between some points in the 3-D world and
of a set of oriented operators whose orthog-
their images in the image plane.
onal cross sections are a Gaussian and the
derivative of a Gaussian. Its advantage is its
camera model (1) the representation of
capability for allowing edges and their orien-
thegeometricandphysicalfeaturesofastere-
tations to be detected to sub-pixel accuracy.
ovision system, with relative references be-
It uses a convolution with a Gaussian to re-
tween the two camera coordinate systems,
duce noise and a derivative to enhance edges
and absolute references to a fixed coordinate
in the resulting smoothed image. The two
system.
are combined into one step — a convolution
(2) a mathematical model by which the with the derivative of a Gaussian. A hystere-
perspective projection on an image plane of sis thresholding stage is included, to allow
a point in the 3-D world can be determined. closed contours to remain closed.
can slang for a pole-top distribution trans- CAP See carrierless amplitude/phase
former. modulation.
capability an object that contains both a
candela (cd) unit of measurement for lu-
pointer to another object and a set of access
minous intensity (illuminating power in lu-
permissions that specify the modes of access
mens/sr). The luminous intensity of 1/60 of permitted to the associated object from a pro-
2
1cm of projected area of a blackbody radi-
cess that holds the capability.
ator operating at the temperature of solidifi-
cation of platinum (2046K). Historically, the
capability curve See capability diagram.
unit of measurement for the light emitted by
one flame of a specified make of candle.
capability diagram also called capabil-
ity curve. Graphical representation of the
candle See candela. complex power limits for safe operation of
a synchronous machine. The vertical axis is
candle power See candela. average power P and the horizontal axis is

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