IBM Netfinity 3000, Руководство пользователя

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O
OBI . Options by IBM.
operating system . Software that
controls the execution of programs
and that may provide services such
as resource allocation, scheduling,
input/output control, and data
management. Although operating
systems are predominantly software,
partial hardware implementations
are possible. (T)
P
p-type semiconductor . A
semiconductor doped with acceptor
impurities that, when energized,
generates a predominance of
positive charge carriers (holes).
Contrast with n-type semiconductor.
See also PMOS.
P-type semiconductors have a lower
level of conductivity than n-type
semiconductors and have slower
switching rates, but allow
higher-density packing of
components. P-type and n-type
semiconductor materials are often
layered together to obtain a
rectifying action between the two
dissimilar materials.
packet . In data communication, a
sequence of binary digits, including
data and control signals, that is
transmitted and switched as a
composite whole. The data, control
signals, and possibly error control
information are arranged in a
specific format. (I)
parallel port . An access point
through which a computer transmits
or receives data that consists of
several bits sent simultaneously on
separate wires. Contrast with serial
port.
parity bit . A check bit appended to
an array of binary digits to make
the sum of all the binary digits,
including the check bit, always odd
or always even. (A)
PCI . Peripheral component
interconnect.
performance . One of the two major
factors, together with facility, on
which the total productivity of a
system depends. Performance is
largely determined by a
combination of throughput,
response time, and availability.
physical
. (1) Pertaining to actual
implementation or location as
opposed to conceptual content or
meaning. (A) (2) Contrast with
logical. (A)
pin . One of the conducting contacts
of an electrical connector.
PMOS
. Positive-channel metal
oxide semiconductor.
port . An access point for data entry
or exit. (Contrast with connector.)
positive metal oxide semiconductor
(PMOS)
. Positive-channel metal
oxide semiconductor. A technology
used in field effect transistors that
utilize the properties of a p-type
semiconductor material, usually
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Netfinity 3000 User's Handbook