All articles starting with D
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Direct Democracy (Polish parliamentary group)
Direct Democracy (Demokracja Bezpośrednia) was a three-member Sejm parliamentary circle of the 9th term, the Kukiz'15 group of Paweł Kukiz, Jarosław Sachajko, and Stanisław Żuk, campaigning for direct democracy.
Direct Democracy Cyprus
Direct Democracy Cyprus (Άμεση Δημοκρατία Κύπρου) is a Cypriot political party founded by MEP Fidias Panayiotou in 2025-2026, letting members vote on policy and candidates via a mobile app; it won 5.4% and four House seats in the May 2026 parliamentary election.
Direct detection (optical communications)
Direct detection in optical communications is a receiver technique in which a photodiode converts received optical power straight into electrical current, measuring only the light's intensity.
Direct detection of dark matter
Direct detection of dark matter is the experimental search for dark matter particles elastically scattering off atomic nuclei or electrons in terrestrial detectors, typically placed deep underground.
Direct detection of the thorium-229 nuclear clock transition
The direct detection of the thorium-229 nuclear clock transition was the first unambiguous observation of the thorium-229 isomer, reported by researchers at LMU Munich in Nature in May 2016.
Direct distance dialing
Direct distance dialing is a North American telephone service feature letting callers dial long-distance numbers, such as area codes, without operator assistance, introduced by the Bell System in 1951.
Direct download link
A direct download link is a URL that delivers a file to the device for saving rather than displaying a hosted page, also known as a DD link.
Direct election
Direct election: citizens vote directly for an officeholder rather than through electors or an electoral college. Contrasted with indirect election (India's presidency, US Electoral College); France adopted direct presidential suffrage in 1962; used in over half of countries with elected parliaments.
Direct electrical stimulation
Direct electrical stimulation is a neurosurgical mapping technique that passes brief electrical currents through exposed brain tissue during surgery, transiently disrupting function to identify eloquent areas before tumor resection.
Direct electrocortical stimulation
Direct electrocortical stimulation (ECS), also called direct electrical stimulation, is a neurosurgical technique that maps functional brain areas during surgery by stimulating the exposed cortex.
Direct electron detector
A direct electron detector is an imaging sensor for transmission electron microscopy in which electrons strike the semiconductor itself, improving efficiency and enabling high-frame-rate movie acquisition.
Direct energy conversion of field-reversed configuration exhaust
Direct energy conversion of field-reversed configuration exhaust turns the energy of an expanding FRC fusion plasma directly into electricity by electromagnetic induction, without a steam cycle.
Direct examination
Direct examination is the initial questioning of a witness at trial by the party that called the witness, conducted without leading questions and generally followed by cross-examination.
Direct fluorescent antibody technique
The direct fluorescent antibody (DFA) technique detects specific antigens directly in patient specimens using fluorescently labeled antibodies read under a microscope, giving results in about an hour.
Direct formic acid fuel cell
A direct formic acid fuel cell is a fuel cell that converts liquid formic acid directly into electricity, studied since the early 2000s for portable power.
Direct imaging (astronomy)
Direct imaging of exoplanets is an observational astronomy technique that records light from planets resolved from their host star, first achieving success with 2M1207b in 2004.
Direct impingement
Direct impingement is a gas operation for self-loading firearms in which propellant gas cycles the action directly, without a piston; it is best known from the AR-15.
Direct infections of joint
Direct infections of joint (ICD-11 FA10, Japanese 関節の直接感染) is a classification category for hematogenic or non-hematogenic joint infections, with child codes for bacterial, viral, and fungal joint infection, excluding reactive and postinfectious arthropathies.
Direct injection
Direct injection is an engine fuel-delivery method that sprays fuel directly into the combustion chamber, used in both diesel engines and, as gasoline direct injection, in spark-ignited cars.
Direct ink writing of liquid crystal elastomers
Direct ink writing of liquid crystal elastomers is an extrusion-based 3D printing method in which shear aligns the ink during extrusion, so the printed path programs molecular orientation and actuation.
Direct instruction
Direct instruction is an explicit, teacher-led teaching method using structured, sequenced lessons that move from teacher modeling to guided practice to independent practice with feedback, associated with Siegfried Engelmann.
Direct integral
A direct integral assembles a family of Hilbert spaces, von Neumann algebras, or operators indexed by a measure space, generalizing the direct sum of Hilbert spaces.
Direct kinematics of parallel manipulators
Direct kinematics of parallel manipulators, also known as forward kinematics, computes a platform's position and orientation from actuator leg lengths; the general six-degree-of-freedom problem has up to 40 solutions.
Direct laryngoscopy
Direct laryngoscopy is a procedure in which a rigid scope passed through the mouth gives direct visualization of the larynx, used for intubation, diagnosis, and surgery.
Direct laser deposition
Direct laser deposition, also called laser directed energy deposition, is an additive manufacturing method that melts metal powder or wire to build parts layer by layer.
Direct laser interference patterning
Direct laser interference patterning (DLIP) is a laser surface texturing method that splits one beam into coherent sub-beams, structuring surfaces at interference maxima without photoresist.
Direct liquefaction of biomass
Direct liquefaction of biomass is the family of thermochemical processes that turn biomass directly into biocrude, mainly by fast pyrolysis and hydrothermal liquefaction, then upgrade it to fuels.
Direct lithium extraction
Direct lithium extraction (DLE) is a family of chemical processes that extracts lithium from brines without solar evaporation, cutting brine-to-carbonate time from about a year to around a day.
Direct marketing
Direct marketing, also known as direct advertising, is promotional communication delivered to selected individuals or businesses through mail, email, telemarketing, and social media to generate a measurable response.
Direct measurement of the quantum wavefunction
Direct measurement of the quantum wavefunction is a technique demonstrated at the National Research Council of Canada in 2011 using a weak measurement followed by a strong one.