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Peregrino Oil and Gas Field
The Peregrino Oil and Gas Field is a heavy-oil field in Brazil's Campos Basin, 85 kilometers offshore Rio de Janeiro, producing around 110,000 barrels daily since 2011.
Perenco
Perenco is a family-owned, independent oil and gas company founded in 1992 by Hubert Perrodo, operating mature and marginal fields in 14 countries rather than pursuing greenfield exploration.
Peresvet (laser weapon)
Peresvet (Пересвет) is a Russian ground-based mobile laser system designed to dazzle or blind the optics of reconnaissance satellites, protecting road-mobile ICBMs; it was declared operational at five Strategic Rocket Forces divisions in December 2019.
Perfect hash function
A perfect hash function, or perfect hashing, maps a fixed set of keys to distinct integers with no collisions, allowing lookup in a single probe.
Perficient
Perficient, Inc. is a global digital consultancy headquartered in St. Louis, Missouri, founded in Austin in the late 1990s and taken private by EQT in a $3.0 billion deal in October 2024.
Perfluorinated graded-index plastic optical fiber
Perfluorinated graded-index plastic optical fiber is a polymer optical fiber whose fluorinated CYTOP core lowers loss and whose graded index suppresses modal dispersion, enabling gigabit short-reach links.
Perfluoroelastomer
A perfluoroelastomer (FFKM) is a fully fluorinated synthetic rubber, designated FFKM under ASTM D1418, that combines the chemical resistance of PTFE with elastomeric recovery, making it the sealing material where conventional rubbers fail.
Perfluoropolyether grease
Perfluoropolyether (PFPE) grease is a synthetic lubricating grease made from fully fluorinated PFPE oil thickened with PTFE, used in vacuum, oxygen, and chemically aggressive service.
Perfluoropolyether lubricant
A perfluoropolyether (PFPE) lubricant is a stable synthetic oil applied as a film under 2 nm on hard disk drive disks, where it has reduced friction and wear for over 30 years.
Perfluorosulfonic acid membrane
A perfluorosulfonic acid membrane is a fully fluorinated proton-conducting polymer, best known as Nafion, developed by DuPont in the 1960s and standard in PEM fuel cells and electrolyzers.
Performance API
The Performance API is a group of web standards for measuring web application performance, providing browser metrics for navigation, resource loading, and rendering, plus developer-defined measurements.
Performance assessment (nuclear waste)
A performance assessment (PA) in radioactive waste disposal is a quantitative evaluation of potential radionuclide releases from a disposal facility and the resulting radiological doses to people.
Performance Based Regulation
Performance based regulation, or performance-based ratemaking, is utility regulation that ties revenues and earnings to achieved outcomes instead of recovered costs, using mechanisms like revenue decoupling and multiyear rate plans.
Performance qualification
Performance qualification (PQ) is the third stage of the four-part qualification model in regulated industries, verifying after installation and operational qualification that equipment and processes perform consistently under normal conditions.
Performance ratio
The performance ratio (PR) is a dimensionless metric for photovoltaic systems, comparing actual delivered energy to ideal output under standard test conditions; typical values run 75 to 90 percent.
Performance specification
A performance specification is a written construction requirement that states the result the work must achieve, such as an acoustic rating, and leaves materials and methods to the contractor.
Performance testing
Performance testing is a software testing practice that measures an application's responsiveness, reliability, scalability, and resource consumption under a workload of concurrent service requests, using types such as load, stress, spike, and endurance testing.
Performance-based rate
A performance-based rate is a solar incentive paying per kilowatt-hour of measured production over several years, used by the California Solar Initiative and Austin Energy, unlike up-front rebates.
Performance-based seismic design
Performance-based seismic design is an earthquake engineering approach in which buildings are designed to explicit performance objectives, such as repair cost, downtime, or casualties, rather than prescriptive code rules.
Performance-graded binder
A performance-graded (PG) binder is an asphalt binder classified under the Superpave system by the high and low pavement temperatures at which it meets specified physical properties.
Performer (transformer architecture)
The Performer is a 2020 transformer architecture from Google Research that approximates softmax attention with linear time and memory complexity via its FAVOR+ mechanism, and was presented at ICLR 2021.
Perfume
Perfume, also called parfum, is a mixture of fragrant essential oils, aroma compounds, solvents, and fixatives used to give the human body, objects, and living spaces a pleasant scent.
Pergola
A pergola is an open garden structure of vertical posts and cross-beams that casts dappled shade, typically freestanding or attached to a building and often planted with climbing vines.
Perimeter control (traffic)
Perimeter control, also called gating or perimeter flow control, is a network-level traffic management strategy that uses boundary traffic signals to limit vehicles entering a region, keeping it productive.
Perimeter frame (motorcycle)
The perimeter frame, also called the twin-spar frame, is a motorcycle chassis of two beams on each side of the engine, standard on modern sport bikes.
Periodogram
The periodogram is a nonparametric estimator of a signal's power spectral density, computed from the squared magnitude of its Fourier transform; Arthur Schuster introduced it in 1898.
Peripheral Component Interconnect
Peripheral Component Interconnect, or PCI bus, is a shared parallel computer bus standard for expansion cards, the primary local bus in personal computers and servers from 1992 until 2004.
Peristaltic pump
A peristaltic pump, also known as a hose pump or roller pump, is a positive displacement pump that moves fluid by rhythmically squeezing a flexible tube, so the fluid touches nothing but the tube.
Perito Moreno Gas Pipeline
The Perito Moreno Gas Pipeline (Gasoducto Perito Francisco Pascasio Moreno, GPM) is a natural gas pipeline in Argentina, built and inaugurated in 2023 as the Gasoducto Presidente Néstor Kirchner.
Perkin Medal
The Perkin Medal is an annual award of SCI America for a US-resident scientist's innovation in applied chemistry, widely acknowledged as the highest honor in American industrial chemistry.