Page 256 - Electrical Engineering Dictionary

emulation mode state describing the time (ciphertext or a cryptogram). The ciphertext
during which a microprocessor is performing can then be transmitted via a communication
emulation. channel without revealing the contents of the
plaintext. This is achieved by means of an
emulator (1) the firmware that simulates encryption key. A system for performing en-
a given machine architecture. cryption is also known as a cipher. The infor-
(2) a device, computer program, or system mation to be encrypted is referred to as plain-
that accepts the same inputs and produces the text, and the encrypted message resulting
same outputs as a given system. Compare from encryption is referred to as ciphertext.
with simulator. The intended receiver of the ciphertext also
has the encryption key, and by having both
EMV See electromagnetic vulnerability. the ciphertext and the encryption key avail-
able, the original plaintext can be recovered.
encapsulation property of a program that See also encryption key, block cipher, stream
describes the complete integration of data cipher, public key cryptography, private key
with legal process relating to the data. cryptography.

enclosure a box, cabinet, wall, fence, encryption key a codeword used for de-
barrier, or other means designed to protect cryption of ciphertext into plaintext in en-
personnel from accidentally contacting ener- cryption systems. Ciphertext can then be
gized electrical parts and to protect the elec- transmitted via a communication channel
trical parts from physical damage. without revealing the contents of the plain-
text. The plaintext can only be recovered by
encoder (1) a device that directly creates someone in possession of the encryption key.
a digital signal based on an analog value. See also encryption, block cipher, stream
(2) a logic circuit with 2 N inputs and N cipher.
outputs, the outputs indicating the number of
the one input line that is asserted. end bell the cap that forms the end of the
(3) a device used to obtain positional in- stator housing for an electric machine with a
formation. The encoder uses a disk mounted cylindrical frame.
on the shaft of a rotating machine and a light
source. The combination provides lights end-around carry technique used in
pulses that can be decoded to provide the an- one’s complement arithmetic, in which a car-
gular position of the motor. See also absolute ryover of the result of an addition or sub-
encoder and incremental encoder. traction beyond the leftmost bit during addi-
tion (or subtraction) is “wrapped around” and
encoding (1) the act of placing informa- added to the result.
tion to be transmitted in a form that can be
transmitted over a particular medium andwill end-effector a part found at the free
be recognizable by the receiver. See also end of the chain of the links which form
coding. a manipulator. Position and orientation of
(2) in computing systems, to represent the manipulator are referred to the end-
various pieces of information by a defined effector. The frame attached the end-effector
sequence of the binary digits 0 and 1, called is known as end-effector frame. The end-
bits. To apply the rules of a code. effector can be a gripper or it can be at-
tached to the end-effector. The orthonormal
encryption the transformation employed end-effector frame consists of three unit vec-
to transform information to be transmitted tors a-approach (it approaches the object) o-
(plaintext) into a format that is unintelligible orientation (which is normal to the sliding

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2000 by CRC Press LLC