All articles starting with R
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Rotary International
Rotary International, founded 23 February 1905 in Chicago by Paul P. Harris, is the global association of about 45,000 Rotary service clubs. Known for Service Above Self and its US$2.9 billion polio eradication effort, it comprises clubs, Rotary International, and The Rotary Foundation.
Rotary position embedding
Rotary position embedding (RoPE) is a method for encoding token positions in transformer models by rotating query and key vectors, introduced in the 2021 RoFormer paper.
Rotary printing press
A rotary printing press prints from a rotating cylinder instead of a flat bed; Richard March Hoe's 1847 press and the 1865 paper web made high-speed newspaper printing possible.
Rotary steerable system
A rotary steerable system is a downhole drilling tool that steers a well directionally while the drill string rotates continuously, first commercialized in the late 1990s.
Rotary switch
A rotary switch is an electromechanical switch whose rotating knob or shaft connects a common terminal to one of several fixed terminals, giving each setting a distinct, visually verifiable position.
Rotary system
The Rotary system was Western Electric's first commercial automatic telephone switching system, using motor-driven rotary selectors under indirect control, with early exchanges in Sweden, France, and England from 1912.
Rotary table
A rotary table is a precision workholding device that rotates a workpiece around a fixed axis, letting a mill or CNC machine cut circular patterns, gears, and multi-face parts in one setup.
Rotary ultrasonic machining
Rotary ultrasonic machining (RUM) is a hybrid process combining diamond grinding with ultrasonic vibration of a rotating tool, used to machine ceramics, glass, and composites.
Rotary vane pump
A rotary vane pump (vane pump) is a positive-displacement pump with a slotted eccentric rotor whose sliding vanes trap fluid and compress it from inlet to outlet.
Rotary variable differential transformer
A rotary variable differential transformer (RVDT) is an electromechanical transducer that measures angular position, producing an AC output voltage proportional to shaft rotation over a linear range of roughly ±40° to ±60°.
Rotary-screw compressor
A rotary-screw compressor, also called a screw compressor, is a positive-displacement compressor that compresses gas between two intermeshing helical rotors in a machined housing, dominating industrial air compression and refrigerant use.
ROTASIIL
ROTASIIL (Rotasiil), Serum Institute of India's oral live attenuated pentavalent rotavirus vaccine (G1-G4, G9), WHO prequalified 2018; 3-dose infant schedule; 67% efficacy in Niger, 36% in India; heat-stable.
ROTASIIL Liquid
ROTASIIL-Liquid (LBRV-PV) is a ready-to-use oral pentavalent rotavirus vaccine by Serum Institute of India, covering G1–G4 and G9, given as 3 doses from 6 weeks of age, WHO prequalified since 2021.
Rotatin
Rotatin (RTTN, MSSP) is a 2,226-amino-acid centrosomal and ciliary basal body protein on human chromosome 18q22.2 required for embryonic left-right specification and centriole structure; biallelic RTTN mutations cause polymicrogyria, microcephaly, and primordial dwarfism.
Rotating artisan service (lunban jiang)
Rotating artisan service (lunban jiang, 轮班匠) was a Ming dynasty corvée system under which registered artisan households took turns serving three-month stints at the capital workshops, instituted in 1386.
Rotating biological contactor
A rotating biological contactor (RBC) is a wastewater treatment process in which plastic discs on a rotating shaft carry a biofilm through sewage, an alternative to activated sludge.
Rotating black hole
A rotating black hole is a black hole with angular momentum, described by the Kerr metric, where spacetime is dragged and rotational energy is extractable.
Rotating detonation engine
A rotating detonation engine (RDE), in rocket form called a rotating detonation rocket engine, burns propellant with a supersonic detonation wave circling an annular chamber, promising higher efficiency.
Rotating inertia (power systems)
Rotating inertia in a power system is the kinetic energy stored in synchronized rotating machines, chiefly synchronous generators, which resists frequency changes when generation and load fall out of balance.
Rotating interior solutions in general relativity
Rotating interior solutions in general relativity are exact solutions describing the inside of a rotating body, exemplified by the Wahlquist metric and constrained by non-existence theorems.
Rotating magnetic field
A rotating magnetic field is a magnetic field that sweeps around in space without mechanical motion; it is produced by phased alternating currents and drives induction motors.
Rotating reference frame
A rotating reference frame is a frame of reference turning at some angular velocity relative to an inertial frame, requiring fictitious forces like the Coriolis and centrifugal forces.
Rotating ring-disk electrode
A rotating ring-disk electrode is an electrochemical working electrode, invented in 1959, whose spinning disk generates products that a surrounding ring electrode detects, chiefly in oxygen reduction studies.
Rotating stall
Rotating stall is an aerodynamic instability of compressors and axial fans in which stalled flow regions rotate around the annulus, lowering pressure rise and stressing blades.
Rotating wave approximation
The rotating wave approximation (RWA) is an approximation in quantum optics and magnetic resonance that drops fast-oscillating counter-rotating Hamiltonian terms, keeping only slowly varying resonant ones.
Rotation
Rotation, also called rotational motion, is the motion of a rigid body in which every point moves in a circle about a common axis or center of rotation.
Rotation (mathematics)
In mathematics, a rotation, also called a coordinate rotation, is a transformation of Euclidean space that preserves distances and orientation, described in 3D by an axis and angle.
Rotation around a fixed axis
Rotation around a fixed axis is the motion of a rigid body in which every point moves in a circle about a single stationary line in space.
Rotation averaging
Rotation averaging is the problem of estimating absolute rotations, typically camera orientations, from many noisy pairwise relative rotation measurements, and it is a key subproblem of global Structure from Motion.
Rotation formalisms in three dimensions
Rotation formalisms in three dimensions, also known as rotation representations, are the mathematical systems used to describe a rigid body's orientation, including rotation matrices, Euler angles, axis-angle, and unit quaternions.