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Standard of Ur
The Standard of Ur, or Royal Standard of Ur, is a mosaic-inlaid wooden box excavated by Leonard Woolley at Ur in the 1920s, now in the British Museum.
Standard Oil
Standard Oil was an American oil refining and pipeline enterprise founded by John D. Rockefeller, which controlled most US petroleum refining until the Supreme Court dissolved it in 1911.
Standard Oil of Ohio (Sohio)
Standard Oil of Ohio, known as Sohio, was an American petroleum company in Cleveland, BP's principal United States arm from 1969 until the brand retired in 1991.
Standard operating procedure
A standard operating procedure (SOP), also called a standing operating procedure, is a written step-by-step document ensuring tasks are performed consistently, accurately, and with quality.
Standard penetration test
The standard penetration test (SPT) is a widely used in-situ geotechnical test that records the hammer blows needed to drive a sampler into soil, giving the N-value.
Standard precautions
Standard precautions are the minimum infection prevention practices applied to every patient in every healthcare setting, regardless of infection status, set out by the CDC in 1996.
Standard probability space
A standard probability space, also known as a Lebesgue-Rokhlin space, is the completion of a standard Borel space with a probability measure, a setting where regular conditional probabilities exist.
Standard quantum limit
The standard quantum limit (SQL), or shot-noise limit, is the precision of an ideal measurement with uncorrelated quantum particles, scaling as N to the −1/2; squeezed light and entanglement can beat it.
Standard RAID levels
The standard RAID levels are numbered configurations, RAID 0 through RAID 6, that combine disk drives into arrays, each trading off performance, capacity, and drive-failure tolerance. They were classified at UC Berkeley in 1988.
Standard Schnauzer
Standard Schnauzer: original medium-sized German Schnauzer breed, 35–45 lb, black or pepper-and-salt wiry coat; formerly Wire-haired Pinscher, AKC-recognized 1904, Working Group since 1937.
Standard score
A standard score, commonly called a z-score, expresses how far an observation lies from its distribution's mean, measured in standard deviations, with values typically between −3 and 3.
Standard siren
A standard siren is an astronomical source, typically a merging compact binary, whose gravitational-wave signal directly encodes its distance, allowing measurements of the Hubble constant.
Standard Solar
Standard Solar is an American commercial and community solar developer, financier, and asset owner in Rockville, Maryland, founded in 2004 and owned by Brookfield Renewable since 2022.
Standard solar model
The standard solar model is a calibrated, one-dimensional mathematical description of the Sun's interior, evolved to its present age of 4.57 billion years and used as the reference for solar neutrino fluxes and helioseismology.
Standard solution
A standard solution is a solution of accurately known concentration, prepared by dissolving a substance of high purity or by standardizing against a primary standard, and used in titrations and instrumental calibration.
Standard step method
The standard step method is an iterative procedure that solves the one-dimensional energy equation step by step between cross sections to compute water surface profiles in open channels.
Standard streams
Standard streams, also called standard channels, are the three predefined input and output channels (stdin, stdout, and stderr) that every running process receives, corresponding to file descriptors 0, 1, and 2.
Standard temperature and pressure
Standard temperature and pressure (STP), or standard conditions, is a reference condition for comparing gas measurements, defined by IUPAC as 0 °C and 1 bar.
Standard Template Library
The Standard Template Library, or C++ STL, is a generic C++ library of containers, algorithms, and iterators designed by Alexander Stepanov and Meng Lee at Hewlett-Packard Labs.
Standard terminal arrival route
A standard terminal arrival route (STAR) is a preplanned IFR air traffic control arrival procedure guiding aircraft from the en route structure to an approach fix.
Standard time
Standard time is the official local clock time of a region when daylight saving time is not in use, first adopted by US and Canadian railroads in 1883.
Standard translation
The standard translation is a translation in modal logic that rewrites propositional modal formulas as first-order logic formulas, turning modal operators into quantifiers over possible worlds.
Standard triple therapy
Standard triple therapy is a Helicobacter pylori eradication regimen combining a proton pump inhibitor with amoxicillin and clarithromycin twice daily, now recommended only where clarithromycin resistance is low.
Standard uncertainty
Standard uncertainty is the estimated standard deviation, denoted u, used to express every component of measurement uncertainty so components can be combined under the GUM framework.
Standard wire gauge
Standard wire gauge, also called British Standard Wire Gauge or Imperial wire gauge, is the legal British standard for wire diameter by gauge number, fixed by Order in Council in 1883.
Standard work
Standard work, also called standardized work, is a lean manufacturing method documenting the best-known way to combine person, machine, and material in a job, enabling consistent repetition and kaizen.
Standard works
The Standard Works are the four canonized scriptures of the Church of Jesus Christ of Latter-day Saints: the Bible, Book of Mormon, Doctrine and Covenants, and Pearl of Great Price.
Standard-definition television
Standard-definition television (SDTV) is a class of digital television formats with lower picture resolution than high definition, typically 480 or 576 active lines in 4:3 or 16:9.
Standard-essential patent
A standard-essential patent (SEP) is a patent without which a product cannot implement a technology standard such as Wi-Fi or 4G, typically licensed on fair, reasonable, and nondiscriminatory terms.
Standard-gauge railway
A standard-gauge railway, also known as Stephenson gauge, has rails 1,435 mm apart, a spacing proposed by George Stephenson and now the world's most widely used railway gauge.