42,772 articles
Full-waveform inversion
Full-waveform inversion (FWI) is a seismic imaging method that iteratively adjusts a subsurface velocity model until simulated seismic waves match recorded survey data, waveform by waveform.
Fuller's earth
Fuller's earth, also known as bleaching earth or Multani Mitti, is any naturally occurring clay with high absorptive capacity, used to clean wool, absorb oils, and decolorize fats.
Fullerene
A fullerene is a closed, hollow cage molecule of carbon atoms, the third allotrope of carbon after diamond and graphite; buckminsterfullerene, C60, was discovered in 1985.
FULLPROF
FULLPROF, or the FullProf Suite, is a crystallographic program suite created by Juan Rodríguez-Carvajal in the early 1990s for Rietveld refinement of powder diffraction data, best known for magnetic structure analysis.
Fully drawn yarn
Fully drawn yarn (FDY) is a synthetic filament yarn, usually polyester, spun and drawn in one continuous process so it can be woven or knitted directly.
Fulton's condition factor
Fulton's condition factor (K) is a fisheries science index of a fish's relative plumpness, calculated as weight divided by the cube of length and assuming isometric growth.
Fulvestrant
Fulvestrant, sold as Faslodex, is a steroidal drug that blocks and degrades the estrogen receptor, used for hormone receptor-positive advanced breast cancer in postmenopausal women.
Fumarate
Fumarate is the dianion of fumaric acid, a four-carbon dicarboxylic acid whose carbon–carbon double bond has trans geometry, serving as a TCA cycle intermediate and signaling molecule.
Fumaric acid
Fumaric acid, also called trans-butenedioic acid, is a white crystalline dicarboxylic acid used as the food acidity regulator E297, in polyester resins, and produced industrially from maleic acid.
Fumarole
A fumarole is an opening in the Earth's surface that emits steam and volcanic gases, forming near active volcanoes or where magma rises without erupting.
Fume hood
A fume hood, also called a fume cupboard, is a ventilated laboratory enclosure that draws toxic vapors and fumes away from the worker and exhausts them outside.
Fumio Hirata
Fumio Hirata (平田 文男) is a Japanese theoretical chemist known for the RISM family of liquid-state theories describing solvation by statistical mechanics, implemented in software such as AMBER.
Fumio Koyama
Fumio Koyama is a Japanese photonics researcher at the Institute of Science Tokyo known for the first continuous room-temperature operation of surface-emitting lasers, used in data centers and face recognition.
Fumonisin B1
Fumonisin B1 (FB1) is a mycotoxin produced by Fusarium molds, chiefly F. verticillioides, that contaminates maize worldwide and disrupts sphingolipid metabolism; it was isolated in 1988 in South Africa.
Function (mathematics)
In mathematics, a function is a relation that assigns each input from a domain exactly one output in a range, written y = f(x); the concept was redefined by Dirichlet in 1829.
Function composition
Function composition, also known as composite function or composition of maps, is an operation on functions where (g∘f)(x) = g(f(x)); it is associative but not commutative.
Function generator
A function generator is an electronic test instrument producing periodic waveforms such as sine, square, and triangle with settable frequency and amplitude, typically built on direct digital synthesis.
Functional (mathematics)
In mathematics, a functional is a function whose input is a function and whose output is a number, central to the calculus of variations and functional analysis.
Functional analysis
Functional analysis is the branch of mathematical analysis that studies functions and operators on infinite-dimensional spaces such as Banach and Hilbert spaces, often described as infinite-dimensional linear algebra.
Functional calculus (logic)
Functional calculus, or first-order predicate logic, is a formal system in which statements about individuals are proved from axioms, and the standard logical framework of mathematics.
Functional clustering
Functional clustering is a set of statistical and machine-learning methods that groups curves, trajectories, and time-varying observations into clusters by shape similarity, treating each observation as a function.
Functional completeness
Functional completeness, also called expressive adequacy, is the property of a set of logical connectives that can express every truth function; NAND and NOR are each complete alone.
Functional derivative
The functional derivative, also called the variational derivative, generalizes the ordinary derivative to functionals, mappings from functions to numbers, and underlies the calculus of variations and the Euler–Lagrange equation.
Functional differential equation
A functional differential equation is a differential equation involving the unknown function at past or future argument values, modeling after-effect systems in physics, biology, economics, and control theory.
Functional equation (L-function)
The functional equation of an L-function is a symmetry relating its values at s to those at 1-s, one of the defining analytic properties of L-functions.
Functional feeding group
A functional feeding group (FFG) is a classification of aquatic macroinvertebrates by their food-acquisition mechanism rather than taxonomy, proposed by Kenneth W. Cummins in 1973 with groups including shredders, collectors, scrapers, and predators.
Functional group
A functional group is an atom or group of atoms whose characteristic chemistry defines families of organic compounds largely regardless of size, sitting on a molecule's unreactive backbone.
Functional group interconversion
Functional group interconversion (FGI) is the conversion of one functional group of an organic molecule into another by substitution, addition, elimination, oxidation, or reduction, keeping the carbon skeleton intact.
Functional principal component analysis
Functional principal component analysis (FPCA) extends principal component analysis to curves, surfaces, and other functions, and is the most widely used technique in functional data analysis.
Functional regression
Functional regression, also known as functional linear regression, is a family of statistical regression methods where predictors or responses are curves, applied to data like imaging and accelerometry.