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PCCW
PCCW is a Hong Kong telecommunications and media company formed when Richard Li's Pacific Century Group acquired the incumbent telephone operator Cable & Wireless HKT in August 2000.
PCI configuration space
The PCI configuration space is a dedicated register address space defined by the PCI Local Bus specification, which firmware and operating systems use to discover PCI devices and assign resources.
PCI Express
PCI Express (PCIe), also known as Peripheral Component Interconnect Express, is a high-speed serial expansion bus standard developed by PCI-SIG, replacing the parallel PCI bus from 2003.
PCI-X
PCI-X (PCI Extended) is a parallel computer expansion bus standard extending PCI with higher clock speeds and a split-transaction protocol, announced by Compaq, Hewlett-Packard, and IBM in 1998.
PCLinuxOS
PCLinuxOS: rolling-release, RPM-based Linux distribution for x86_64, forked from Mandrake 9.2 in October 2003 by Texstar; live-installable ISOs (KDE, MATE, Xfce), apt-rpm moving to DNF, own 12,000-package repository.
PCloud
pCloud is a Swiss cloud storage service founded in 2013 and registered in Baar, Switzerland, offering file storage, sync, sharing, backup, media streaming, and a paid client-side encrypted folder.
PCP (complexity class)
PCP(r, q) is a complexity class of languages checkable by a probabilistic verifier using O(r) random bits and O(q) proof queries; the PCP theorem states NP equals PCP(O(log n), O(1)).
PCP (complexity)
PCP, or probabilistically checkable proof, is a proof format for NP statements that a randomized verifier can check by reading only a few positions of the proof.
PCP theorem
The PCP theorem is a result in computational complexity theory stating that NP equals PCP(log n, 1), so NP proofs can be verified by reading constant bits.
PD controller
A PD controller, or proportional-derivative controller, is a feedback control strategy combining a term proportional to error with one proportional to its rate of change.
PDDL
PDDL, or Planning Domain Definition Language, is a standardized formal language for describing planning domains and problem instances to automated planners, created in 1998 for the AIPS-98 planning competition.
PDF, or Portable Document Format, is a fixed-layout file format developed by Adobe and launched in 1993, made an ISO standard in 2008 and used for contracts, reports, forms, and papers.
PDF Solutions
PDF Solutions, Inc. is a Santa Clara, California provider of analytics software, test hardware, and services for semiconductor manufacturing, founded in 1991 and traded on Nasdaq as PDFS.
PDF/A
PDF/A is a family of ISO standards (ISO 19005) defining PDF variants for the long-term preservation of electronic documents, first published in 2005, with PDF/A-4 released in 2020.
PDF417
PDF417 is a two-dimensional stacked barcode symbology invented in 1991 by Ynjiun P. Wang at Symbol Technologies, standardized as ISO/IEC 15438, and used on US and Canadian driver licenses and airline boarding passes.
PDP-1
The PDP-1, also known as the DEC PDP-1, was the first computer sold by Digital Equipment Corporation, an 18-bit interactive machine first shipped in November 1960.
PDP-10
The PDP-10, marketed as the DECsystem-10, was a 36-bit mainframe computer family made by Digital Equipment Corporation from 1967 to 1983, influential in timesharing and the early ARPANET.
PDP-11
The PDP-11 was a family of 16-bit minicomputers sold by Digital Equipment Corporation of Maynard, Massachusetts, from 1970 into the 1990s, with about 600,000 units sold.
PDP-8
The PDP-8, also known as the DEC PDP-8, is a 12-bit minicomputer introduced by Digital Equipment Corporation in 1965, considered the first commercially successful minicomputer.
PDVSA
PDVSA, or Petróleos de Venezuela, S.A., is Venezuela's state-owned oil and gas company, created in 1975 and given control of the nationalized oil industry in 1976.
PDX (tokamak)
PDX (Poloidal Divertor Experiment) was a tokamak at the Princeton Plasma Physics Laboratory that tested poloidal divertors for impurity control, operated from 1978 to 1983, and was converted into PBX.
PdZn intermetallic catalysts
PdZn intermetallic catalysts are heterogeneous catalysts based on ordered palladium–zinc compounds, most prominently β-PdZn, whose copper-like electronic structure makes them candidates for methanol synthesis and steam reforming.
Peabody Energy
Peabody Energy is a St. Louis-based coal company founded in Chicago in 1883, among the largest U.S. coal producers with mines in the United States and Australia.
PEACE (submarine cable)
PEACE (Pakistan & East Africa Connecting Europe) is a privately owned submarine communications cable linking Singapore, Pakistan, Kenya, Egypt, and France, fully activated from Singapore to Marseille in 2024.
Peace Bridge
The Peace Bridge is a toll bridge over the Niagara River connecting Buffalo, New York, with Fort Erie, Ontario. Opened in 1927, it is one of the busiest border crossings.
Peace Bridge (Foyle)
The Peace Bridge, Derry is an S-shaped pedestrian and cycle bridge over the River Foyle, opened in 2011 to link the city center with the Waterside.
Peace Pipeline (Canada)
The Peace Pipeline is a natural gas liquids pipeline system in western Canada owned and operated by Pembina Pipeline Corporation, carrying ethane-plus, propane-plus, and condensate from northeastern British Columbia and Alberta to Edmonton.
Peacekeeper Rail Garrison
The Peacekeeper Rail Garrison was a US Air Force plan of the late 1980s to base 50 Peacekeeper intercontinental ballistic missiles on 25 trains, terminated in 1991 before deployment.
Peach Bottom nuclear power plant
Peach Bottom Atomic Power Station is a two-unit nuclear power plant near Delta, Pennsylvania, with two boiling water reactors generating about 2,770 MW, co-owned by Constellation and PSEG.
Peachoid
The Peachoid is a 135-foot water tower in Gaffney, South Carolina, shaped and painted like a giant peach, holding one million gallons for Cherokee County.