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In thermodynamics , vapor quality is the mass fraction in a saturated mixture that is vapor ; [ 1 ] in other words, saturated vapor has a "quality" of 100%, and saturated liquid has a "quality" of 0%. Vapor quality is an intensive property which can be used in conjunction with other independent intensive properties to... | https://en.wikipedia.org/wiki/Vapor_quality |
Vaporization (or vapo(u)risation) of an element or compound is a phase transition from the liquid phase to vapor . [ 1 ] There are two types of vaporization: evaporation and boiling . Evaporation is a surface phenomenon , whereas boiling is a bulk phenomenon (a phenomenon in which the whole object or substance is invol... | https://en.wikipedia.org/wiki/Vaporization |
In thermodynamics and chemical engineering , the vapor–liquid equilibrium ( VLE ) describes the distribution of a chemical species between the vapor phase and a liquid phase .
The concentration of a vapor in contact with its liquid, especially at equilibrium , is often expressed in terms of vapor pressure , which will... | https://en.wikipedia.org/wiki/Vapor–liquid_equilibrium |
In chemical engineering , a vapor–liquid separator is a device used to separate a vapor–liquid mixture into its constituent phases . It can be a vertical or horizontal vessel, and can act as a 2-phase or 3-phase separator.
A vapor–liquid separator may also be referred to as a flash drum , breakpot , knock-out drum or ... | https://en.wikipedia.org/wiki/Vapor–liquid_separator |
The vapor–liquid–solid method ( VLS ) is a mechanism for the growth of one-dimensional structures, such as nanowires , from chemical vapor deposition . The growth of a crystal through direct adsorption of a gas phase on to a solid surface is generally very slow. The VLS mechanism circumvents this by introducing a catal... | https://en.wikipedia.org/wiki/Vapor–liquid–solid_method |
The vapour-phase-mediated antimicrobial activity (VMAA) is the inhibitory or cidal antimicrobial activity of a molecule in a liquid culture , following its initial evaporation and migration via the vapour-phase [ 1 ] Two new in vitro assays i.e. the vapour-phase-mediated patch assay [ 2 ] and the vapour-phase-mediated ... | https://en.wikipedia.org/wiki/Vapour-phase-mediated_antimicrobial_activity |
The vapor pressure of water is the pressure exerted by molecules of water vapor in gaseous form (whether pure or in a mixture with other gases such as air). The saturation vapor pressure is the pressure at which water vapor is in thermodynamic equilibrium with its condensed state . At pressures higher than saturation v... | https://en.wikipedia.org/wiki/Vapour_pressure_of_water |
In mathematics , Varadhan's lemma is a result from the large deviations theory named after S. R. Srinivasa Varadhan . The result gives information on the asymptotic distribution of a statistic φ ( Z ε ) of a family of random variables Z ε as ε becomes small in terms of a rate function for the variables.
Let X be a re... | https://en.wikipedia.org/wiki/Varadhan's_lemma |
The reflected binary code ( RBC ), also known as reflected binary ( RB ) or Gray code after Frank Gray , is an ordering of the binary numeral system such that two successive values differ in only one bit (binary digit).
For example, the representation of the decimal value "1" in binary would normally be " 001 ", and "... | https://en.wikipedia.org/wiki/Varec_code |
Vargulin , [ 1 ] also called Cypridinid luciferin , [ 2 ] Cypridina luciferin , or Vargula luciferin , is the luciferin found in the ostracod Cypridina hilgendorfii , also named Vargula hilgendorfii . [ 3 ] These bottom dwelling ostracods emit a light stream into water when disturbed presumably to deter predation. Varg... | https://en.wikipedia.org/wiki/Vargulin |
The variability hypothesis , also known as the greater male variability hypothesis , is the hypothesis that human males generally display greater variability in traits than human females do.
It has often been discussed in relation to human cognitive ability , where some studies appear to show that males are more likel... | https://en.wikipedia.org/wiki/Variability_hypothesis |
A variable-buoyancy pressure vessel system is a type of rigid buoyancy control device for diving systems that retains a constant volume and varies its density by changing the weight (mass) of the contents, either by moving the ambient fluid into and out of a rigid pressure vessel, or by moving a stored liquid between i... | https://en.wikipedia.org/wiki/Variable-buoyancy_pressure_vessel |
A variable frequency oscillator ( VFO ) in electronics is an oscillator whose frequency can be tuned (i.e., varied) over some range. [ 1 ] It is a necessary component in any tunable radio transmitter and in receivers that work by the superheterodyne principle. The oscillator controls the frequency to which the apparatu... | https://en.wikipedia.org/wiki/Variable-frequency_oscillator |
In mechanics , a variable-mass system is a collection of matter whose mass varies with time . It can be confusing to try to apply Newton's second law of motion directly to such a system. [ 1 ] [ 2 ] Instead, the time dependence of the mass m can be calculated by rearranging Newton's second law and adding a term to acco... | https://en.wikipedia.org/wiki/Variable-mass_system |
In mathematics , a variable (from Latin variabilis ' changeable ' ) is a symbol , typically a letter, that refers to an unspecified mathematical object . [ 1 ] [ 2 ] [ 3 ] One says colloquially that the variable represents or denotes the object, and that any valid candidate for the object is the value of the variable. ... | https://en.wikipedia.org/wiki/Variable_(mathematics) |
Variable air volume ( VAV ) is a type of heating, ventilating, and/or air-conditioning ( HVAC ) system. Unlike constant air volume (CAV) systems, which supply a constant airflow at a variable temperature, VAV systems vary the airflow at a constant or varying temperature. [ 1 ] [ 2 ] The advantages of VAV systems over ... | https://en.wikipedia.org/wiki/Variable_air_volume |
In science and research , an attribute is a quality of an object (person, thing, etc.). [ 1 ] Attributes are closely related to variables. A variable is a logical set of attributes. [ 1 ] Variables can "vary" – for example, be high or low. [ 1 ] How high, or how low, is determined by the value of the attribute (and in ... | https://en.wikipedia.org/wiki/Variable_and_attribute_(research) |
Variable bitrate ( VBR ) is a term used in telecommunications and computing that relates to the bitrate used in sound or video encoding. As opposed to constant bitrate (CBR), VBR files vary the amount of output data per time segment. VBR allows a higher bitrate (and therefore more storage space) to be allocated to th... | https://en.wikipedia.org/wiki/Variable_bitrate |
A variable cycle engine ( VCE ), also referred to as adaptive cycle engine ( ACE ), is an aircraft jet engine that is designed to operate efficiently under mixed flight conditions, such as subsonic , transonic and supersonic .
An advanced technology engine is a turbine engine that allows different turbines to spin at ... | https://en.wikipedia.org/wiki/Variable_cycle_engine |
A variable electro-precipitator (VEP) is a waste water remediation unit using electrocoagulation . The differences between a standard electrocoagulation (EC) unit and a variable Electro-precipitation unit are in the enhanced flow path and the unit electrode connections. The variable electro-precipitator's flow path has... | https://en.wikipedia.org/wiki/Variable_electro-precipitator |
A variable geometry turbomachine uses movable vanes to optimize its efficiency at different operating conditions. This article refers to movable vanes as used in liquid pumps and turbocharger turbines. It does not cover the widespread use of movable vanes in gas turbine compressors.
If all fluid velocities at correspo... | https://en.wikipedia.org/wiki/Variable_geometry_turbomachine |
A variable rate feeder (often shortened to belt feeder , or simply feeder ) is a piece of industrial control equipment used to deliver solid material at a known rate into some process.
In both form and function, belt feeders are essentially short belt conveyors . There are a few key areas in which the two differ, howe... | https://en.wikipedia.org/wiki/Variable_rate_feeder |
A variable star is a star whose brightness as seen from Earth (its apparent magnitude ) changes systematically with time. This variation may be caused by a change in emitted light or by something partly blocking the light, so variable stars are classified as either: [ 1 ]
Many, possibly most, stars exhibit at least so... | https://en.wikipedia.org/wiki/Variable_star |
A variable structure system , or VSS , is a discontinuous nonlinear system of the form
where x ≜ [ x 1 , x 2 , … , x n ] T ∈ R n {\displaystyle \mathbf {x} \triangleq [x_{1},x_{2},\ldots ,x_{n}]^{\operatorname {T} }\in \mathbb {R} ^{n}} is the state vector, t ∈ R {\displaystyle t\in \mathbb {R} } is the time variable,... | https://en.wikipedia.org/wiki/Variable_structure_system |
In probability theory and statistics , variance is the expected value of the squared deviation from the mean of a random variable . The standard deviation (SD) is obtained as the square root of the variance. Variance is a measure of dispersion , meaning it is a measure of how far a set of numbers is spread out from the... | https://en.wikipedia.org/wiki/Variance |
In microbiology and virology , the term variant or genetic variant is used to describe a subtype of a microorganism that is genetically distinct from a main strain, but not sufficiently different to be termed a distinct strain . A similar distinction is made in botany between different cultivated varieties of a species... | https://en.wikipedia.org/wiki/Variant_(biology) |
Variants of PCR represent a diverse array of techniques that have evolved from the basic polymerase chain reaction (PCR) method, each tailored to specific applications in molecular biology , such as genetic analysis, DNA sequencing , and disease diagnosis, by modifying factors like primer design, temperature conditions... | https://en.wikipedia.org/wiki/Variants_of_PCR |
In computational physics , variational Monte Carlo (VMC) is a quantum Monte Carlo method that applies the variational method to approximate the ground state of a quantum system. [ 1 ]
The basic building block is a generic wave function | Ψ ( a ) ⟩ {\displaystyle |\Psi (a)\rangle } depending on some parameters a {\disp... | https://en.wikipedia.org/wiki/Variational_Monte_Carlo |
In quantum mechanics , the variational method is one way of finding approximations to the lowest energy eigenstate or ground state , and some excited states. This allows calculating approximate wavefunctions such as molecular orbitals . [ 1 ] The basis for this method is the variational principle . [ 2 ] [ 3 ]
The met... | https://en.wikipedia.org/wiki/Variational_method_(quantum_mechanics) |
In science and especially in mathematical studies, a variational principle is one that enables a problem to be solved using calculus of variations , which concerns finding functions that optimize the values of quantities that depend on those functions. For example, the problem of determining the shape of a hanging chai... | https://en.wikipedia.org/wiki/Variational_principle |
In evolutionary biology, the variational properties of an organism are those properties relating to the production of variation among its offspring. In a broader sense variational properties include phenotypic plasticity. [ 1 ] [ 2 ] [ 3 ] Variational properties contrast with functional properties. While the functional... | https://en.wikipedia.org/wiki/Variational_properties |
Variational transition-state theory [ 1 ] is a refinement of transition-state theory . When using transition-state theory to estimate a chemical reaction rate , the dividing surface is taken to be a surface that intersects a first-order saddle point and is also perpendicular to the reaction coordinate in all other dim... | https://en.wikipedia.org/wiki/Variational_transition-state_theory |
In the mathematical fields of the calculus of variations and differential geometry , the variational vector field is a certain type of vector field defined on the tangent bundle of a differentiable manifold which gives rise to variations along a vector field in the manifold itself.
Specifically, let X be a vector fiel... | https://en.wikipedia.org/wiki/Variational_vector_field |
Varicode is a self-synchronizing code for use in PSK31 . It supports all ASCII characters, but the characters used most frequently in English have shorter codes. The space between characters is indicated by a 00 sequence, an implementation of Fibonacci coding . Originally created for speeding up real-time keyboard-to-... | https://en.wikipedia.org/wiki/Varicode |
Variegation is the appearance of differently coloured zones in the foliage , flowers , and sometimes the stems and fruit of plants , granting a speckled, striped, or patchy appearance. The colors of the patches themselves vary from a slightly lighter shade of the natural coloration to yellow, to white, or other colors ... | https://en.wikipedia.org/wiki/Variegation |
In mathematics , and more precisely in semigroup theory, a variety of finite semigroups is a class of semigroups satisfying specific algebraic properties. Those classes can be defined in two distinct ways, using either algebraic notions or topological notions. Varieties of finite monoids , varieties of finite ordered s... | https://en.wikipedia.org/wiki/Variety_of_finite_semigroups |
In Euclidean geometry , Varignon's theorem holds that the midpoints of the sides of an arbitrary quadrilateral form a parallelogram , called the Varignon parallelogram . It is named after Pierre Varignon , whose proof was published posthumously in 1731. [ 1 ]
The midpoints of the sides of an arbitrary quadrilateral fo... | https://en.wikipedia.org/wiki/Varignon's_theorem |
Varignon's theorem is a theorem of French mathematician Pierre Varignon (1654–1722), published in 1687 in his book Projet d'une nouvelle mécanique . The theorem states that the torque of a resultant of two concurrent forces about any point is equal to the algebraic sum of the torques of its components about the same po... | https://en.wikipedia.org/wiki/Varignon's_theorem_(mechanics) |
The variome is the whole set of genetic variations found in populations of species that have gone through a relatively short evolution change. For example, among humans, about 1 in every 1,200 [ citation needed ] nucleotide bases differ. The size of human variome in terms of effective population size is claimed to be a... | https://en.wikipedia.org/wiki/Variome |
In aviation , a variometer – also known as a rate of climb and descent indicator ( RCDI ), rate-of-climb indicator , vertical speed indicator ( VSI ), or vertical velocity indicator ( VVI ) – is one of the flight instruments in an aircraft used to inform the pilot of the rate of descent or climb . [ 1 ] It can be calib... | https://en.wikipedia.org/wiki/Variometer |
A variscale is variable length mechanical scale (ruler) designed to directly measure latitude and longitude on USGS maps. [ 1 ]
This cartography or mapping term article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Variscale |
The Varrentrapp reaction , also named Varrentrapp degradation , is a name reaction in the organic chemistry . It is named after Franz Varrentrapp, who described this reaction in 1840. [ 1 ] The reaction entails the degradation of an unsaturated carboxylic acid into a saturated acid with two fewer carbon atoms and aceti... | https://en.wikipedia.org/wiki/Varrentrapp_reaction |
Vartkess Ara Apkarian (born 1955) is an Armenian-American physical chemist and a Professor of Chemistry at The University of California, Irvine . [ 1 ]
He is the Director of Center for Chemistry at the Space-Time Limit , a National Science Foundation Center for Chemical Innovation . He graduated from University of Sou... | https://en.wikipedia.org/wiki/Vartkess_Ara_Apkarian |
Vascular endothelial growth factor ( VEGF , / v ɛ dʒ ˈ ɛ f / ), originally known as vascular permeability factor ( VPF ), [ 1 ] is a signal protein produced by many cells that stimulates the formation of blood vessels. To be specific, VEGF is a sub-family of growth factors , the platelet-derived growth factor family of... | https://en.wikipedia.org/wiki/Vascular_endothelial_growth_factor |
A vascular malformation is a type of vascular anomaly . [ 2 ] They may cause aesthetic problems as they have a growth cycle, and can continue to grow throughout life.
Vascular malformations of the brain include those involving capillaries , and those involving the veins and arteries . Capillary malformations in the br... | https://en.wikipedia.org/wiki/Vascular_malformation |
Vascular plants (from Latin vasculum ' duct ' ), also called tracheophytes ( UK : / ˈ t r æ k iː ə ˌ f aɪ t s / , [ 5 ] US : / ˈ t r eɪ k iː ə ˌ f aɪ t s / ) [ 6 ] or collectively tracheophyta ( / ˌ t r eɪ k iː ˈ ɒ f ɪ t ə / ; [ 7 ] [ 8 ] [ 9 ] from Ancient Greek τραχεῖα ἀρτηρία ( trakheîa artēría ) ' windpipe ' and φυ... | https://en.wikipedia.org/wiki/Vascular_plant |
Vascularity , in bodybuilding , is the condition of having many highly visible, prominent, and often extensively-ramified superficial veins . [ 1 ] The skin appears "thin"—sometimes virtually transparent —due to an extreme reduction of subcutaneous fat , allowing for maximum muscle definition. [ citation needed ]
Vasc... | https://en.wikipedia.org/wiki/Vascularity |
Vasculogenesis is the process of blood vessel formation, occurring by a de novo production of endothelial cells . [ 1 ] It is the first stage of the formation of the vascular network, closely followed by angiogenesis . [ 2 ] [ 3 ]
In the sense distinguished from angiogenesis , vasculogenesis is different in one aspect... | https://en.wikipedia.org/wiki/Vasculogenesis |
A vasculum or a botanical box is a stiff container used by botanists to keep field samples viable for transportation. The main purpose of the vasculum is to transport plants without crushing them and by maintaining a cool, humid environment .
Vascula are cylinders typically made from tinned and sometimes lacquered iro... | https://en.wikipedia.org/wiki/Vasculum |
A vase ( Swedish pronunciation: [ˈ̍vɑːsːɛ] ⓘ ) is a heraldic symbol that has been used by the Swedish and Polish-Lithuanian House of Vasa . It has been used as a symbol of the Swedish state even after the extinction of the Vasa lineage, and was reused in 1818 as part of the coat of arms of Sweden . The vase has been us... | https://en.wikipedia.org/wiki/Vase_(heraldry) |
Vasilis M. Fthenakis is a Greek American chemical engineer , environmental scientist, author and academic. He is an adjunct professor, and founding director of the center for Life Cycle Analysis at Columbia University . [ 1 ] [ 2 ]
Fthenakis is most known for his research on the environmental sustainability of photovo... | https://en.wikipedia.org/wiki/Vasilis_Fthenakis |
Vasilis Gregoriou (born 1965, Trikala, Greece) [ 1 ] is a researcher, inventor, technology entrepreneur and former Director and Chairman of the Board of Directors at National Hellenic Research Foundation (NHRF) in Athens, Greece. [ 2 ] [ 3 ] [ 4 ] During his career, he has achieved international recognition by serving... | https://en.wikipedia.org/wiki/Vasilis_Gregoriou |
Vasily Leonidovich Omelianski ( Vasilij Leonidovič Omeljanskij , Russian: Василий Леонидович Омелянский ; 10 March 1867 – 21 April 1928) was a Russian microbiologist and author of the first original Russian text book on microbiology. He was the only student of Sergei Winogradsky and succeeded him as head of the departm... | https://en.wikipedia.org/wiki/Vasily_Omelianski |
Vasishtha Siddhanta is one of the earliest astronomical systems in use in India, which is summarized in Varahamihira 's Pancha-siddhantika (6th century). It is attributed to sage Vasishtha and claims a date of composition of 1,299,101 BCE. [ 1 ] The original text probably dated to the 4th century, but it has been lost ... | https://en.wikipedia.org/wiki/Vasishtha_Siddhanta |
Vaterite is a mineral, a polymorph of calcium carbonate ( Ca C O 3 ). It was named after the German mineralogist Heinrich Vater . It is also known as mu- calcium carbonate (μ-CaCO 3 ). Vaterite belongs to the hexagonal crystal system , whereas calcite is trigonal and aragonite is orthorhombic .
Vaterite, like aragonit... | https://en.wikipedia.org/wiki/Vaterite |
In mathematics and analytic number theory , Vaughan's identity is an identity found by R. C. Vaughan ( 1977 ) that can be used to simplify Vinogradov 's work on trigonometric sums . It can be used to estimate summatory functions of the form
where f is some arithmetic function of the natural integers n , whose values i... | https://en.wikipedia.org/wiki/Vaughan's_identity |
In astronomy , the Vaughan–Preston gap is an observed absence of F-, G- and K-type stars with intermediate levels of magnetic activity . In 1980, Vaughan and Preston noted there were two populations of stars of these classifications, with either high or low levels of activity, separated by an apparent gap. [ 1 ] There... | https://en.wikipedia.org/wiki/Vaughan–Preston_gap |
The Vaught conjecture is a conjecture in the mathematical field of model theory originally proposed by Robert Lawson Vaught in 1961. It states that the number of countable models of a first-order complete theory in a countable language is finite or ℵ 0 or 2 ℵ 0 . Morley showed that the number of countable models is f... | https://en.wikipedia.org/wiki/Vaught_conjecture |
Vault 7 is a series of documents that WikiLeaks began to publish on 7 March 2017, detailing the activities and capabilities of the United States Central Intelligence Agency (CIA) to perform electronic surveillance and cyber warfare . The files, dating from 2013 to 2016, include details on the agency's software capabili... | https://en.wikipedia.org/wiki/Vault_7 |
A Vavilov center or center of origin is a geographical area where a group of organisms, either domesticated or wild, first developed its distinctive properties. [ 1 ] Centers of origin were first identified in 1924 by Nikolai Vavilov . Vavilov posited that the center of origin for a species or genus is the same as its ... | https://en.wikipedia.org/wiki/Vavilov_center |
Vaxart, Inc. is an American biotechnology company focused on the discovery, development, and commercialization of oral recombinant vaccines administered using temperature-stable tablets that can be stored and shipped without refrigeration, eliminating the need for needle injection. Its development programs for oral vac... | https://en.wikipedia.org/wiki/Vaxart |
In mathematics , the Veblen functions are a hierarchy of normal functions ( continuous strictly increasing functions from ordinals to ordinals), introduced by Oswald Veblen in Veblen (1908) . If φ 0 is any normal function, then for any non-zero ordinal α , φ α is the function enumerating the common fixed points of φ β ... | https://en.wikipedia.org/wiki/Veblen_function |
A vector-valued function , also referred to as a vector function , is a mathematical function of one or more variables whose range is a set of multidimensional vectors or infinite-dimensional vectors . The input of a vector-valued function could be a scalar or a vector (that is, the dimension of the domain could be 1 o... | https://en.wikipedia.org/wiki/Vector-valued_function |
VectorDB was a database of sequence information for common vectors used in molecular biology [ 1 ]
This Biological database -related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/VectorDB |
In molecular cloning , a vector is any particle (e.g., plasmids , cosmids , Lambda phages ) used as a vehicle to artificially carry a foreign nucleic sequence – usually DNA – into another cell , where it can be replicated and/or expressed . [ 1 ] A vector containing foreign DNA is termed recombinant DNA . The four majo... | https://en.wikipedia.org/wiki/Vector_(molecular_biology) |
In mathematics , the Laplace operator or Laplacian is a differential operator given by the divergence of the gradient of a scalar function on Euclidean space . It is usually denoted by the symbols ∇ ⋅ ∇ {\displaystyle \nabla \cdot \nabla } , ∇ 2 {\displaystyle \nabla ^{2}} (where ∇ {\displaystyle \nabla } is the nabla ... | https://en.wikipedia.org/wiki/Vector_Laplacian |
Vector Product Format (VPF) is a military standard for vector -based digital map products produced by the U.S. Department of Defense (DOD). It has been adopted as part of the Digital Geographic Exchange Standard (DIGEST) in the form of Vector Relational Format (VRF), so VPF can be considered to be an international stan... | https://en.wikipedia.org/wiki/Vector_Product_Format |
The following are important identities in vector algebra . Identities that only involve the magnitude of a vector ‖ A ‖ {\displaystyle \|\mathbf {A} \|} and the dot product (scalar product) of two vectors A · B , apply to vectors in any dimension, while identities that use the cross product (vector product) A × B only ... | https://en.wikipedia.org/wiki/Vector_algebra_relations |
In particle physics , a vector boson is a boson whose spin equals one. Vector bosons that are also elementary particles are gauge bosons , the force carriers of fundamental interactions . Some composite particles are vector bosons, for instance any vector meson ( quark and antiquark ). During the 1970s and 1980s, inter... | https://en.wikipedia.org/wiki/Vector_boson |
The following are important identities involving derivatives and integrals in vector calculus .
For a function f ( x , y , z ) {\displaystyle f(x,y,z)} in three-dimensional Cartesian coordinate variables, the gradient is the vector field:
where i , j , k are the standard unit vectors for the x , y , z -axes. More gen... | https://en.wikipedia.org/wiki/Vector_calculus_identities |
Note: This page uses common physics notation for spherical coordinates, in which θ {\displaystyle \theta } is the angle between the z axis and the radius vector connecting the origin to the point in question, while ϕ {\displaystyle \phi } is the angle between the projection of the radius vector onto the x-y plane and t... | https://en.wikipedia.org/wiki/Vector_fields_in_cylindrical_and_spherical_coordinates |
In mathematics , the discussion of vector fields on spheres was a classical problem of differential topology , beginning with the hairy ball theorem , and early work on the classification of division algebras .
Specifically, the question is how many linearly independent smooth nowhere-zero vector fields can be constru... | https://en.wikipedia.org/wiki/Vector_fields_on_spheres |
In physics, vector meson dominance (VMD) was a model developed by J. J. Sakurai [ 1 ] in the 1960s before the introduction of quantum chromodynamics to describe interactions between energetic photons and hadronic matter.
In particular, the hadronic components of the physical photon consist of the lightest vector meson... | https://en.wikipedia.org/wiki/Vector_meson_dominance |
In vector calculus , a vector potential is a vector field whose curl is a given vector field. This is analogous to a scalar potential , which is a scalar field whose gradient is a given vector field.
Formally, given a vector field v {\displaystyle \mathbf {v} } , a vector potential is a C 2 {\displaystyle C^{2}} vecto... | https://en.wikipedia.org/wiki/Vector_potential |
The vector projection (also known as the vector component or vector resolution ) of a vector a on (or onto) a nonzero vector b is the orthogonal projection of a onto a straight line parallel to b .
The projection of a onto b is often written as proj b a {\displaystyle \operatorname {proj} _{\mathbf {b} }\mathbf {a} ... | https://en.wikipedia.org/wiki/Vector_projection |
The vector projection (also known as the vector component or vector resolution ) of a vector a on (or onto) a nonzero vector b is the orthogonal projection of a onto a straight line parallel to b .
The projection of a onto b is often written as proj b a {\displaystyle \operatorname {proj} _{\mathbf {b} }\mathbf {a} ... | https://en.wikipedia.org/wiki/Vector_projection_on_a_plane |
In spectroscopy and radiometry , vector radiative transfer (VRT) is a method of modelling the propagation of polarized electromagnetic radiation in low density media. In contrast to scalar radiative transfer (RT), which models only the first Stokes component , the intensity, VRT models all four components through vect... | https://en.wikipedia.org/wiki/Vector_radiative_transfer |
A vector signal analyzer is an instrument that measures the magnitude and phase of the input signal at a single frequency within the IF bandwidth of the instrument. The primary use is to make in-channel measurements, such as error vector magnitude , code domain power, and spectral flatness , on known signals.
Vector s... | https://en.wikipedia.org/wiki/Vector_signal_analyzer |
In mathematics , vector spherical harmonics ( VSH ) are an extension of the scalar spherical harmonics for use with vector fields . The components of the VSH are complex-valued functions expressed in the spherical coordinate basis vectors .
Several conventions have been used to define the VSH. [ 1 ] [ 2 ] [ 3 ] [ 4 ] ... | https://en.wikipedia.org/wiki/Vector_spherical_harmonics |
Vectorette PCR is a variation of polymerase chain reaction (PCR) designed in 1988. [ 1 ] The original PCR was created and also patented during the 1980s. [ 2 ] Vectorette PCR was first noted and described in an article in 1990 by John H. Riley and his team. [ 3 ] Since then, multiple variants of PCR have been created. ... | https://en.wikipedia.org/wiki/Vectorette_PCR |
Gene therapy utilizes the delivery of DNA into cells, which can be accomplished by several methods, summarized below. The two major classes of methods are those that use recombinant viruses (sometimes called biological nanoparticles or viral vectors) and those that use naked DNA or DNA complexes (non-viral methods).
A... | https://en.wikipedia.org/wiki/Vectors_in_gene_therapy |
A vectorscope is a special type of oscilloscope used in both audio and video applications. [ 1 ] Whereas an oscilloscope or waveform monitor normally displays a plot of signal vs. time, a vectorscope displays an X-Y plot of two signals, which can reveal details about the relationship between these two signals. Vectorsc... | https://en.wikipedia.org/wiki/Vectorscope |
In crystallography , materials science and metallurgy , Vegard's law is an empirical finding ( heuristic approach) resembling the rule of mixtures . In 1921, Lars Vegard discovered that the lattice parameter of a solid solution of two constituents is approximately a weighted mean of the two constituents' lattice parame... | https://en.wikipedia.org/wiki/Vegard's_law |
The Vegetable Production System ( Veggie ) is a plant growth system developed and used by NASA in space environments. The purpose of Veggie is to provide a self-sufficient and sustainable food source for astronauts as well as a means of recreation and relaxation through therapeutic gardening. [ 2 ] Veggie was designed ... | https://en.wikipedia.org/wiki/Vegetable_Production_System |
Vegetation is an assemblage of plant species and the ground cover they provide. [ 2 ] It is a general term, without specific reference to particular taxa , life forms, structure, spatial extent, or any other specific botanical or geographic characteristics. It is broader than the term flora which refers to species comp... | https://en.wikipedia.org/wiki/Vegetation |
Vegetation classification is the process of classifying and mapping the vegetation over an area of the Earth's surface. Vegetation classification is often performed by state based agencies as part of land use, resource and environmental management. Many different methods of vegetation classification have been used. In ... | https://en.wikipedia.org/wiki/Vegetation_classification |
A vegetation index ( VI ) is a spectral imaging transformation of two or more image bands designed to enhance the contribution of vegetation properties and allow reliable spatial and temporal inter-comparisons of terrestrial photosynthetic activity and canopy structural variations. [ 2 ] [ 3 ]
There are many VIs, with... | https://en.wikipedia.org/wiki/Vegetation_index |
Vegetative reproduction (also known as vegetative propagation , vegetative multiplication or cloning ) is a form of asexual reproduction occurring in plants in which a new plant grows from a fragment or cutting of the parent plant or specialized reproductive structures, which are sometimes called vegetative propagules... | https://en.wikipedia.org/wiki/Vegetative_reproduction |
A Vegetative Treatment System (VTS) is a combination of treatment steps for managing runoff . It treats runoff by settling, infiltrating , and nutrient usage. Individual components of a VTS include, a settling structure, an outlet structure, a distribution system, and a Vegetative Treatment Area (VTA). All these compon... | https://en.wikipedia.org/wiki/Vegetative_treatment_system |
A vehicle (from Latin vehiculum ) [ 1 ] is a machine designed for self- propulsion , usually to transport people, cargo , or both. The term "vehicle" typically refers to land vehicles such as human-powered vehicles (e.g. bicycles , tricycles , velomobiles ), animal-powered transports (e.g. horse-drawn carriages / wagon... | https://en.wikipedia.org/wiki/Vehicle |
Vehicle-to-device (V2D) communication is a particular type of vehicular communication system that consists in the exchange of information between a vehicle and any electronic device that may be connected to the vehicle itself.
The ever-increasing tendency of developing mobile applications for our everyday use has ulti... | https://en.wikipedia.org/wiki/Vehicle-to-device |
Vehicle-to-everything ( V2X ) describes wireless communication between a vehicle and any entity that may affect, or may be affected by, the vehicle. Sometimes called C-V2X , it is a vehicular communication system that is intended to improve road safety and traffic efficiency while reducing pollution and saving energy.
... | https://en.wikipedia.org/wiki/Vehicle-to-everything |
Vehicle Information and Communication System ( VICS ) is a technology used in Japan for delivering traffic and travel information to road vehicle drivers. It provides simple maps showing information about traffic jams, travel time, and road work - usually relevant to your location and usually incorporating infrared bea... | https://en.wikipedia.org/wiki/Vehicle_Information_and_Communication_System |
Vehicle dynamics is the study of vehicle motion, e.g., how a vehicle's forward movement changes in response to driver inputs, propulsion system outputs, ambient conditions, air/surface/water conditions, etc.
Vehicle dynamics is a part of engineering primarily based on classical mechanics .
It may be applied for motoriz... | https://en.wikipedia.org/wiki/Vehicle_dynamics |
A vehicle frame , also historically known as its chassis , is the main supporting structure of a motor vehicle to which all other components are attached, comparable to the skeleton of an organism.
Until the 1930s, virtually every car had a structural frame separate from its body, known as body-on-frame construction. ... | https://en.wikipedia.org/wiki/Vehicle_frame |
A Vehicular ad hoc network ( VANET ) is a proposed type of mobile ad hoc network (MANET) involving road vehicles. [ 1 ] VANETs were first proposed [ 2 ] in 2001 as " car-to-car ad-hoc mobile communication and networking" applications, where networks could be formed and information could be relayed among cars. It has be... | https://en.wikipedia.org/wiki/Vehicular_ad_hoc_network |
Vehicular automation is the use of technology to assist or replace the operator of a vehicle such as a car, truck, aircraft, rocket, military vehicle, or boat. [ 2 ] [ 3 ] [ 4 ] [ 5 ] [ 6 ] Assisted vehicles are semi-autonomous , whereas vehicles that can travel without a human operator are autonomous . [ 3 ] The degre... | https://en.wikipedia.org/wiki/Vehicular_automation |
Vehicular communication systems are computer networks in which vehicles and roadside units are the communicating nodes , providing each other with information, such as safety warnings and traffic information. They can be effective in avoiding accidents and traffic congestion. Both types of nodes are dedicated short-ran... | https://en.wikipedia.org/wiki/Vehicular_communication_systems |
Velocimetry is the measurement of the velocity of fluids . This is a task often taken for granted, and involves far more complex processes than one might expect. It is often used to solve fluid dynamics problems, study fluid networks, in industrial and process control applications, as well as in the creation of new kin... | https://en.wikipedia.org/wiki/Velocimetry |
In relativistic physics , a velocity-addition formula is an equation that specifies how to combine the velocities of objects in a way that is consistent with the requirement that no object's speed can exceed the speed of light . Such formulas apply to successive Lorentz transformations , so they also relate different f... | https://en.wikipedia.org/wiki/Velocity-addition_formula |
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