All articles starting with S
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Sedeinga
Sedeinga is an archaeological site on the west bank of the Nile in Sudan, combining a temple built for Queen Tiye around 1360 BC with a large pyramid necropolis.
SEDEMAC
SEDEMAC, or Sedemac Mechatronics Limited, is a Pune-based automotive-electronics company founded in 2007 by IIT Bombay professor Shashikanth Suryanarayanan that makes engine control units for two- and three-wheelers.
Sedenion
A sedenion is a 16-dimensional hypercomplex number, the fifth algebra in the Cayley–Dickson sequence after the octonions: non-associative and non-alternative, but power-associative, and the first to contain zero divisors.
Sedenions
Sedenions are 16-dimensional noncommutative, nonassociative algebras over the real numbers, obtained by applying the Cayley-Dickson construction to the octonions; unlike the octonions, they contain zero divisors.
Sedentary lifestyle
The sedentary lifestyle, or sedentarism, is a way of living dominated by sitting or lying with very low energy expenditure, which raises the risk of diabetes and heart disease.
Sedentism
Sedentism is year-round residence in one settlement, contrasted with hunter-gatherer mobility. It preceded agriculture in the Natufian Levant, arose with millet in wetter north China after 8.1 ka, and appears among high-altitude Tibetan foragers.
Sedevacantism
Sedevacantism is the traditionalist Catholic position that the popes since 1958, or 1963, are not legitimate, so the See of Peter is vacant; it emerged after Vatican II.
Sedge meadows and tussock tundra
Sedge meadows and tussock tundra are wetland ecosystems dominated by sedges such as Carex stricta and Eriophorum vaginatum, which build peat and store large amounts of carbon.
Sedges of North America
Sedges of North America describes the sedge family Cyperaceae north of Mexico: 843 species in 27 genera, with Carex alone holding 480 species, about 57% of the flora.
Sedges of the British Isles
The sedges of the British Isles are the sedges, cotton-grasses, club-rushes, and allies of Britain and Ireland, about 85 species, covered by the BSBI's 2007 handbook of the same name.
Sedgwick County, Kansas, United States
Sedgwick County, Kansas: south-central county established 1867, seat Wichita, the state's largest city. Population 538,433 (2025 est.); aviation, agriculture, and a 2026 data center zoning pause.
Sedibeng District Municipality
Sedibeng District Municipality (DC42) is a Category C district municipality in southern Gauteng, South Africa, covering the Vaal Triangle with Emfuleni, Lesedi, and Midvaal local municipalities; manufacturing-dominated economy and grant-dependent finances.
Sediment
Sediment is loose, uncemented rock, mineral, or biological material that settles out of water or air into layers; most ultimately comes to rest in the ocean.
Sediment budget
A sediment budget is an accounting of the sources, storage, and export of sediment in a system such as a watershed, applying conservation of mass.
Sediment bypassing
Sediment bypassing is the transfer of sand from the updrift to the downdrift side of a coastal barrier like a tidal inlet, preventing erosion and channel shoaling.
Sediment connectivity
Sediment connectivity is the degree of linkage controlling sediment fluxes between sources and downstream areas of a catchment, measured with the index of connectivity derived from elevation models.
Sediment delivery ratio
The sediment delivery ratio (SDR) is the fraction of soil eroded within a drainage basin that actually reaches the basin outlet, typically below 1 because sediment is deposited en route.
Sediment flushing
Sediment flushing is a reservoir management operation in which low-level outlets in a dam are opened so flowing water carries deposited sediment downstream, recovering storage lost to sedimentation.
Sediment resuspension
Sediment resuspension is the mobilization of settled bed sediment back into the water column when bottom shear stress exceeds a critical value, driven mainly by wind, waves, and currents.
Sediment sorting
Sediment sorting is the process by which transport and deposition separate sediment grains of different sizes, producing downstream fining, armored streambeds, and graded deposits in rivers.
Sediment transport capacity
Sediment transport capacity is the maximum sediment load a flow can carry under given hydraulic conditions, defined by G. K. Gilbert in 1877 and 1914.
Sediment transport model
A sediment transport model is a mathematical or numerical model simulating sediment movement by water, wind, or ice, used in dredging assessment, coastal morphodynamics, and hazard studies.
Sediment trap
A sediment trap is an oceanographic instrument, typically a funnel with a collection cup, that catches particles sinking toward the sea floor to measure carbon and nutrient fluxes.
Sediment yield
Sediment yield is the amount of sediment delivered from a drainage area over time, typically the annual load passing a gauging station on the stream.
Sedimentary ancient DNA
Sedimentary ancient DNA (sedaDNA) is genetic material from past organisms preserved in lake, marine, and cave sediments, used to reconstruct past ecosystems, with permafrost records reaching 2 million years.
Sedimentary basin
Sedimentary basin: a subsiding lithospheric depression filled with sediment, formed by plate-tectonic subsidence mechanisms (stretching, cooling, loading). Classified into rift, foreland, intracratonic and other types; hosts petroleum, groundwater, and CO2 storage.
Sedimentary rock
Sedimentary rock, also known as sedimentary stone or aqueous rock, forms at the Earth's surface from accumulated sediment consolidated by compaction and cementation, typically showing layers and containing fossils.
Sedimentation
Sedimentation is the deposition of loose sediments, rock and mineral fragments, or biological materials that settle out of water or air into layers, eventually becoming sedimentary rock.
Sedimentation (water treatment)
Sedimentation in water treatment is a solid-liquid separation process in which suspended particles settle by gravity in a quiescent basin, used for clarification in drinking water and wastewater plants.
Sedimentation analysis
Sedimentation analysis is a particle size analysis method that measures how fast particles settle through a liquid, converting settling velocity into an equivalent sphere diameter with Stokes's law.