Page 245 - Electrical Engineering Dictionary

edge elements the basis functions that are Edison Electric Institute a trade group
associated with the edges of the discretizing of investor-owned public electric utilities in
elements (such as triangles, tetrahedrals, etc.) the USA.
in a numerical method such as finite element
method. edit distance the edit distance between
two string A and B is defined as
edge enhancement a type of image pro-
D edit = min{a + b + c}
cessing operation where edges are enhanced
in contrast, such as by passing only the high
where B is obtained from A with a replace-
spatial frequencies in an image.
ments, b insertions, and c deletions. There is
an infinite number of combinations {a, b, c}
edge guide two conductor transmission to achieve this. One of the ways to find the
lines in which one of the conductors is a thin minimum from these is dynamic program-
sheet of width substantially larger than the ming. Edit distance is also called Leven-
gap to the second conductor. The guided shtein distance.
wave is largest at the edge or boundary of
the thin sheet conductor, standing across to EEG See electroencephalography.
the second conductor, and propagating in the
direction of the thin sheet conductor edge or EEPROM See electronically erasable
boundary. programmable read-only memory.

effective address (1) the computed ad-
edge-sensitive pertaining to a bistable de-
dress of a memory operation.
vice that uses the edge of a positive or neg-
(2) the final actual address used in a pro-
ative pulse applied to the control input, to
gram. It is usually 32 or 64 bits wide.
latch, capture, or store the value indicated by
The effective address is created from the
the data inputs.
relative address within a segment (that is, rel-
ative to the base of a segment), which has had
edge-triggered See edge-sensitive. applied all address modification specified in
the instruction word. Depending on the con-
figuration of the memory management unit,
Edison, Thomas Alva (1847–1931)
the effective address may be different from
Born: Milan, Ohio, U.S.A.
the real address used by a program, i.e., the
Edison is best known as the holder of 1069 address in RAM, ROM, or I/O space where
patents secured during his lifetime. Among the operation occurs.
these were patents for the phonograph and (3) when a memory location is referenced
the incandescent filament lamp. Edison was by a machine instruction, the actual memory
largely self-taught. His early interest in com- address specified by the addressing mode is
munication devices stemmed from his em- called the effective address. For example, if
ployment as a telegraph operator. He used an instruction uses an indirect mode of ad-
the profits from the sale of his first invention, dressing, the effective address is to be found
a “stock ticker,” to set up a lab in Newark, in the register or memory location whose ad-
New Jersey. Always a shrewd commercial dress appears in the instruction.
developer, he followed the invention of the
light bulb with work on developing efficient effective aperture a figure of merit for an
generators to power these bulbs. Edison is antenna giving the equivalent aperture size
considered the archetypal American inven- required to intercept from a field of uniform
tive genius. power density an amount of power equal to

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