All articles starting with O
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Overhead crane
An overhead crane is a crane with a movable bridge carrying a hoist on an overhead runway, the standard lifting machine of factories, steel mills, and power plants.
Overhead ground wire
An overhead ground wire, also called a shield wire, static wire, earth wire, or skywire, is a grounded conductor atop power lines that intercepts lightning strokes.
Overhead line
An overhead line, also called overhead contact system or overhead line equipment, is a system of energized wires that supplies electric power to moving trains through a pantograph, from trams to high-speed lines.
Overhead power line
An overhead power line, also known as a high tension line, carries electric power through conductors suspended above the ground on poles or towers, using air as insulation.
Overhead projector
An overhead projector is a display device that throws an enlarged image of a transparency onto a screen, standard in classrooms from the 1960s to the 2000s.
Overhead stirrer
An overhead stirrer is a laboratory mixing device in which a motor above the vessel drives a shaft and impeller directly, used for volumes and viscosities beyond what a magnetic stirrer can handle.
Overhead valve engine
An overhead valve (OHV) engine, also called a pushrod engine, is a piston engine with valves in the cylinder head operated by pushrods from a camshaft in the block.
Overheard (窃听风云)
Overheard (窃听风云) is a 2009 Hong Kong crime thriller by Alan Mak and Felix Chong, starring Lau Ching-wan, Louis Koo, and Daniel Wu as surveillance cops who trade on overheard insider information; it topped Hong Kong's 2009 local summer box office and spawned two sequels.
Overheard 2 (窃听风云2)
Overheard 2 (窃听风云2) is a 2011 Hong Kong crime thriller by Alan Mak and Felix Chong, starring Lau Ching-wan, Louis Koo, and Daniel Wu as new characters in a surveillance and stock-manipulation story about the Landlord Club; it earned 2.08亿元 and five Hong Kong Film Award nominations.
Overheard 3 (窃听风云3)
Overheard 3 (竊聽風雲3) is a 2014 Hong Kong crime thriller, third in the Overheard series, directed by Alan Mak and Felix Chong, starring Lau Ching-wan, Louis Koo, and Daniel Wu in a New Territories land-grant (Small House Policy) scheme plot; it won three Hong Kong Film Awards.
Overhydrated hereditary stomatocytosis
Overhydrated hereditary stomatocytosis (OHST, hydrocytosis, OMIM 185000) is a rare autosomal dominant hemolytic anemia caused by RHAG mutations, with cation-leaky overhydrated stomatocytes, absent stomatin, and contraindicated splenectomy.
Overinvestment
Overinvestment is investment beyond what future returns or the economy's structure can absorb, generating less real value than it costs, with the gap absorbed through rising debt.
Overkill (band)
Overkill: New Jersey thrash metal band formed in 1980, named after Motörhead's 1979 album; fronted since founding by Bobby "Blitz" Ellsworth and D.D. Verni, with twenty studio albums from Feel the Fire (1985) to Scorched (2023).
Overkill (Motörhead album)
Overkill (Motörhead album): Motörhead's second studio album, released March 24, 1979 on Bronze, produced by Jimmy Miller; its title track was performed on Top of the Pops in 1979.
Overkill's The Walking Dead
Overkill's The Walking Dead is a 2018 four-player co-op first-person shooter by OVERKILL, set in post-apocalyptic Washington, D.C. It was withdrawn from sale in 2019.
Overland Campaign
The Overland Campaign (May 4 to mid-June 1864) was Grant's Virginia drive against Lee's Army of Northern Virginia, fought at the Wilderness, Spotsylvania, North Anna, and Cold Harbor, ending with the James crossing and the Petersburg siege.
Overland Park, Kansas
Overland Park, Kansas: second-largest city in Kansas, in Johnson County southwest of Kansas City. Founded 1905 by William B. Strang Jr., incorporated 1960; about 204,000 residents, major employers include Fiserv's Aspiria fintech hub.
Overland Pass NGL Pipeline
The Overland Pass Pipeline is a natural gas liquids pipeline carrying NGLs from Opal, Wyoming, to Conway, Kansas, owned equally by Williams and ONEOK and operated by Williams.
Overland telegraphy in colonial Africa
Overland telegraphy in colonial Africa was the landline telegraph networks built across the continent's colonies from the 1860s to the mid-twentieth century, serving imperial control more than commerce.
Overlap fermions
Overlap fermions are lattice fermions introduced by Herbert Neuberger in 1997, whose Dirac operator satisfies the Ginsparg–Wilson relation exactly, giving lattice QCD exact chiral symmetry without fermion doubling.
Overlap myositis
Overlap myositis (non-specific myositis, ORPHA:206572) is a subtype of idiopathic inflammatory myopathy combining myositis with clinical or autoantibody features of another connective tissue disease, common in adult women, with frequent interstitial lung disease.
Overlapping circles grid
An overlapping circles grid is a geometric pattern of congruent circles centered on a lattice, with radii large enough that neighbors overlap, often built on a triangular lattice.
Overlapping domain decomposition
Overlapping domain decomposition solves a partial differential equation by splitting its domain into overlapping subdomains, solving local problems in parallel, and exchanging interface data until they combine.
Overlapping gene
Overlapping gene: a gene sharing nucleotides with another gene, encoding two proteins in different reading frames. Also called dual-coding genes; first found in phage φX174, common in viruses (53% of genomes), arising mainly by overprinting.
Overlapping generations model
The overlapping generations (OLG) model is a macroeconomic model in which finite-lived generations coexist, introduced by Paul Samuelson in 1958 and used to analyze pensions, public debt, and money.
Overlapping Surgery
Overlapping surgery: one primary attending surgeon runs two operating rooms with staggered critical portions, distinct from prohibited concurrent surgery; CMS-approved, ethically debated, and studied across 200,000+ patients.
Overlay analysis
Overlay analysis is a geographic information system technique combining two or more spatial data layers, such as land use and soils, to identify areas meeting combined criteria.
Overlay Denture
Overlay denture (overdenture): removable dental prosthesis built over natural tooth roots or implants, per MeSH D003828. Tooth-supported and implant-supported types; attachments include ball, bar, locator, magnet, telescopic; two-implant mandibular IOD is standard since 2002.
Overlay metrology
Overlay metrology is the measurement of how precisely successive patterned layers of a semiconductor device are aligned, a critical process control step in chip manufacturing.
Overlay network
An overlay network is a virtual network built on top of another network, whose logical connections run over paths the underlying physical network forwards without understanding them.