All articles starting with D
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Delta Orionis
Delta Orionis (δ Orionis, Mintaka) is the westernmost star of Orion's Belt, a magnitude 2.4 multiple star system containing the nearest massive eclipsing binary, with an O-type pair orbiting every 5.7 days.
Delta Pavonis
Delta Pavonis (δ Pavonis) is a nearby G8 IV subgiant star in the southern constellation Pavo, about 19.92 light-years from Earth and visible to the naked eye.
Delta potential
The delta potential, also called the delta function potential, is an exactly solvable quantum mechanics model with potential V = ±αδ(x), zero except at one point.
Delta Programme
The Delta Programme (Deltaprogramma) is the Netherlands' national program for flood protection, freshwater supplies, and climate-resilient planning, directed by a Delta Commissioner and financed by a Delta Fund under the 2012 Delta Act.
Delta Queen
The Delta Queen is an American sternwheel steamboat built in 1926, the flagship overnight passenger steamboat of the Mississippi and Ohio river system from 1948 to 2008.
Delta robot
The Delta robot is a parallel robot with three purely translational degrees of freedom, invented by Reymond Clavel at EPFL in 1985 for handling small, light objects.
Delta rule
The delta rule, also called the Widrow–Hoff rule or LMS rule, is a supervised learning rule for neural networks developed by Bernard Widrow and Marcian Hoff in 1960.
Delta Scorpii
Delta Scorpii, also known as Dschubba, is a bright B-type star in the head of Scorpius about 400 light-years away, long considered stable until its major outburst in 2000.
Delta Scuti
A Delta Scuti (δ Sct) variable is a pulsating A- to F-type star near the main sequence, with short periods from about 15 minutes to 5 hours.
Delta Scuti variable
A Delta Scuti variable, also called a dwarf cepheid, is a pulsating variable star of spectral type A0 to F5, named for the prototype Delta Scuti.
Delta Sharing
Delta Sharing is an open REST protocol launched by Databricks in 2021 under the Linux Foundation for secure zero-copy sharing of live Delta Lake and Parquet datasets across platforms and clouds; it evolved into OpenSharing in 2026.
Delta Sigma Theta
Delta Sigma Theta Sorority, Inc. is a historically African American service sorority founded in 1913 at Howard University, with over 300,000 members and more than 900 chapters.
Delta State
Delta State is a state in southern Nigeria created in 1991 from Bendel State, with its capital at Asaba and oil and gas as its economic mainstay.
Delta Tau Delta
Delta Tau Delta, a men's social fraternity founded in 1858 at Bethany College, West Virginia, with truth, courage, faith, and power as principles; 130+ chapters, 170,000+ initiates, and documented hazing cases at NAU, Penn State, and Ball State.
Delta Tau Power PMAC
The Delta Tau Power PMAC is a family of multi-axis motion controllers and embedded machine computers by Delta Tau Data Systems, now sold by Omron under names like CK3E.
Delta Tauri
Delta Tauri is the Bayer designation for three stars in Taurus, all members of the Hyades cluster: δ¹ Tauri, a K-type giant, plus δ² and δ³ Tauri.
Delta Trianguli
Delta Trianguli (δ Trianguli), officially named Deltoton by the IAU in 2025, is a double-lined spectroscopic binary star about 35 light-years away in Triangulum, with a G-type primary orbiting a lower-mass companion every 10.02 days.
Delta wave
Delta wave: high-amplitude 1–4 Hz (band 0.1–<4 Hz) EEG rhythm dominating N3 slow-wave sleep; also seen in anesthesia and coma, generated by thalamic h-current/T-current interactions and cortical layer 5 circuits; named by Walter in 1936.
Delta wing
The delta wing is a triangular, highly swept, low-aspect-ratio aircraft wing planform named for the Greek letter Δ, which became the standard shape for supersonic aircraft.
Delta Works
The Delta Works, or Deltawerken, are dams and storm surge barriers in the Netherlands built after the 1953 North Sea flood to protect the delta.
Delta-aminolevulinic acid dehydratase
Delta-aminolevulinic acid dehydratase (ALAD, porphobilinogen synthase, EC 4.2.1.24) condenses two 5-aminolevulinate molecules into porphobilinogen in heme biosynthesis; a zinc or magnesium metalloenzyme, octameric TIM-barrel, and lead's most sensitive toxicological target.
Delta-beta thalassemia
Delta-beta thalassemia (δβ-thalassemia) is a beta-thalassemia variant, usually caused by deletions of the delta and beta genes on chromosome 11, that keeps fetal hemoglobin elevated for life.
Delta-cadinene
Delta-cadinene is a bicyclic sesquiterpene hydrocarbon, C15H24, made in cotton as the first committed intermediate in gossypol biosynthesis, also found in tea, hops, and iris, and dehydrogenating to cadalene, a higher-plant biomarker.
Delta-class submarine
The Delta class (Дельта) is a series of Soviet nuclear-powered ballistic missile submarines built in four versions, the backbone of the Soviet and Russian strategic fleet since 1973.
Delta-hemolysin
Delta-hemolysin (delta-toxin, delta-lysin, PSMgamma) is a 26-amino-acid amphipathic alpha-helical hemolytic peptide from Staphylococcus aureus, encoded by hld within RNAIII of the agr locus, and a phenol-soluble modulin family member.
Delta-K
Delta-K is the restartable hypergolic second stage of the Delta II rocket, powered by an Aerojet AJ10-118K engine, flown from 1989 to the final Delta II flight.
Delta-matroid
A delta-matroid is a combinatorial structure that generalizes a matroid by replacing equicardinal bases with feasible sets of varying sizes, introduced independently in the mid-1980s by André Bouchet and others.
Delta-Mendota Canal
The Delta-Mendota Canal is an irrigation canal in central California, built from 1946 to 1952 to carry water from the Sacramento-San Joaquin Delta south to the San Joaquin Valley.
Delta-sarcoglycan-related limb-girdle muscular dystrophy R6
Delta-sarcoglycan-related limb-girdle muscular dystrophy R6 (LGMD R6, formerly LGMD2F) is a rare autosomal recessive muscular dystrophy caused by SGCD gene variants, typically beginning in childhood.
Delta-sigma modulation
Delta-sigma modulation, also called sigma-delta, is an analog-to-digital conversion method that oversamples the signal and uses feedback to shape quantization noise out of the signal band.