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In parapatric speciation , two subpopulations of a species evolve reproductive isolation from one another while continuing to exchange genes . This mode of speciation has three distinguishing characteristics: 1) mating occurs non-randomly, 2) gene flow occurs unequally, and 3) populations exist in either continuous or ... | https://en.wikipedia.org/wiki/Parapatric_speciation |
Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic with respect to the excluded subgroups. In contrast, a monophyletic grouping (a clade ) includes a common ancestor and all of ... | https://en.wikipedia.org/wiki/Paraphyly |
In mathematics , a paraproduct is a non-commutative bilinear operator acting on functions that in some sense is like the product of the two functions it acts on. According to Svante Janson and Jaak Peetre, in an article from 1988, [ 1 ] "the name 'paraproduct' denotes an idea rather than a unique definition; several ve... | https://en.wikipedia.org/wiki/Paraproduct |
Paraquat ( trivial name ; / ˈ p ær ə k w ɒ t / ), or N , N ′-dimethyl-4,4′-bipyridinium dichloride ( systematic name ), also known as methyl viologen , is a toxic organic compound with the chemical formula [(C 6 H 7 N) 2 ]Cl 2 . It is classified as a viologen , a family of redox -active heterocycles of similar structur... | https://en.wikipedia.org/wiki/Paraquat |
The parasexual cycle , a process restricted to fungi and single-celled organisms , is a nonsexual mechanism of parasexuality for transferring genetic material without meiosis or the development of sexual structures. [ 1 ] It was first described by Italian geneticist Guido Pontecorvo in 1956 during studies on Aspergillu... | https://en.wikipedia.org/wiki/Parasexual_cycle |
Parasite Rex: Inside the Bizarre World of Nature's Most Dangerous Creatures is a nonfiction book by Carl Zimmer that was published by Free Press in 2000. The book discusses the history of parasites on Earth and how the field and study of parasitology formed, along with a look at the most dangerous parasites ever found ... | https://en.wikipedia.org/wiki/Parasite_Rex |
Parasite load is a measure of the number and virulence of the parasites that a host organism harbours. Quantitative parasitology deals with measures to quantify parasite loads in samples of hosts and to make statistical comparisons of parasitism across host samples.
In evolutionary biology , parasite load has importan... | https://en.wikipedia.org/wiki/Parasite_load |
Parasitic chromosomes are "selfish" chromosomes that propagate throughout cell divisions, even if they confer no benefit to the overall organism's survival. Parasitic chromosomes can persist even if slightly detrimental to survival, as is characteristic of some selfish genetic elements. Parasitic chromosomes are often ... | https://en.wikipedia.org/wiki/Parasitic_chromosome |
Parasitic computing is a technique where a program in normal authorized interactions with another program manages to get the other program to perform computations of a complex nature without exploiting vulnerabilities to execute attacker-supplied code on the latter. It is, in a sense, a security exploit in that the pro... | https://en.wikipedia.org/wiki/Parasitic_computing |
Parasitic oscillation is an undesirable electronic oscillation (cyclic variation in output voltage or current) in an electronic or digital device. It is often caused by feedback in an amplifying device. The problem occurs notably in RF , [ 1 ] audio , and other electronic amplifiers [ 2 ] as well as in digital signal ... | https://en.wikipedia.org/wiki/Parasitic_oscillation |
Parasitology is the study of parasites , their hosts , and the relationship between them. As a biological discipline , the scope of parasitology is not determined by the organism or environment in question but by their way of life. This means it forms a synthesis of other disciplines, and draws on techniques from field... | https://en.wikipedia.org/wiki/Parasitology |
A paraspecies (a paraphyletic species) is a species , living or fossil, that gave rise to one or more daughter species without itself becoming extinct . [ 1 ] Geographically widespread species that have given rise to one or more daughter species as peripheral isolates without themselves becoming extinct (i.e. through p... | https://en.wikipedia.org/wiki/Paraspecies |
The parasternal line is a vertical line on the front of the thorax. It is midway between the lateral sternal line and the mid-clavicular line .
This anatomy article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Parasternal_line |
A parasympatholytic agent is a substance or activity that reduces the activity of the parasympathetic nervous system . [ 1 ] [ 2 ]
The term parasympatholytic typically refers to the effect of a drug , although some poisons act to block the parasympathetic nervous system as well. Most drugs with parasympatholytic prope... | https://en.wikipedia.org/wiki/Parasympatholytic |
Parataxonomy is a system of labor division for use in biodiversity research, in which the rough sorting tasks of specimen collection, field identification, documentation and preservation are conducted by primarily local, less specialized individuals, thereby alleviating the workload for the "alpha" or "master" taxonomi... | https://en.wikipedia.org/wiki/Parataxonomy |
In mathematics, the paratingent cone and contingent cone were introduced by Bouligand ( 1932 ), and are closely related to tangent cones .
Let S {\displaystyle S} be a nonempty subset of a real normed vector space ( X , ‖ ⋅ ‖ ) {\displaystyle (X,\|\cdot \|)} .
An equivalent definition is given in terms of a distance ... | https://en.wikipedia.org/wiki/Paratingent_cone |
Paratomy is a form of asexual reproduction in animals where the organism splits in a plane perpendicular to the antero-posterior axis and the split is preceded by the "pregeneration" of the anterior structures in the posterior portion. The developing organisms have their body axis aligned, i.e., they develop in a head ... | https://en.wikipedia.org/wiki/Paratomy |
Paratransgenesis is a technique that attempts to eliminate a pathogen from vector populations through transgenesis of a symbiont of the vector. The goal of this technique is to control vector-borne diseases . The first step is to identify proteins that prevent the vector species from transmitting the pathogen. The gene... | https://en.wikipedia.org/wiki/Paratransgenesis |
In zoology and botany , a paratype is a specimen of an organism that helps define what the scientific name of a species and other taxon actually represents, but it is not the holotype (and in botany is also neither an isotype nor a syntype ). Often there is more than one paratype. Paratypes are usually held in museum r... | https://en.wikipedia.org/wiki/Paratype |
List of ediacaran genera for more.
Parazoa ( Parazoa , gr. Παρα-, para, "next to", and ζωα, zoa, "animals") is an obsolete subkingdom that is located at the base of the phylogenetic tree of the animal kingdom in opposition to the subkingdom Eumetazoa ; they group together the most primitive forms, characterized by not... | https://en.wikipedia.org/wiki/Parazoa |
Parbuckle salvage , or parbuckling , is the righting of a sunken vessel using rotational leverage. A common operation with smaller watercraft , parbuckling is also employed to right large vessels. In 1943, the USS Oklahoma was rotated nearly 180 degrees to upright after being sunk in the attack on Pearl Harbor , and t... | https://en.wikipedia.org/wiki/Parbuckle_salvage |
In mathematics education, a parent function is the core representation of a function type without manipulations such as translation and dilation. [ 1 ] For example, for the family of quadratic functions having the general form
the simplest function is
and every quadratic may be converted to that form by translations ... | https://en.wikipedia.org/wiki/Parent_function |
In chemistry , a parent hydride in IUPAC nomenclature refers to a main group compound with the formula AH n , where A is a main group element. The names of parent hydrides end with -ane , analogous with the nomenclature for alkanes . Derivatives of parent hydrides are named by appending prefixes or suffixes to the name... | https://en.wikipedia.org/wiki/Parent_hydride |
In chemistry , a parent structure is the structure of an unadorned ion or molecule from which derivatives can be visualized. [ 1 ] Parent structures underpin systematic nomenclature and facilitate classification. Fundamental parent structures have one or no functional groups and often have various types of symmetry. Be... | https://en.wikipedia.org/wiki/Parent_structure |
Parental care is a behavioural and evolutionary strategy adopted by some animals, involving a parental investment being made to the evolutionary fitness of offspring. Patterns of parental care are widespread and highly diverse across the animal kingdom. [ 1 ] There is great variation in different animal groups in terms... | https://en.wikipedia.org/wiki/Parental_care |
Parental investment , in evolutionary biology and evolutionary psychology , is any parental expenditure (e.g. time, energy, resources) that benefits offspring . [ 1 ] [ 2 ] Parental investment may be performed by both males and females (called biparental care ), females alone ( exclusive maternal care ) or males alone ... | https://en.wikipedia.org/wiki/Parental_investment |
Within the cells of some members of basidiomycetes fungi are found microscopic structures called parenthesomes or septal pore caps . They are shaped like parentheses and found on either side of pores in the dolipore septum which separates cells within a hypha . Their function has not been established, and their compos... | https://en.wikipedia.org/wiki/Parenthesome |
Parent–offspring conflict ( POC ) is an expression coined in 1974 by Robert Trivers . It is used to describe the evolutionary conflict arising from differences in optimal parental investment (PI) in an offspring from the standpoint of the parent and the offspring . PI is any investment by the parent in an individual of... | https://en.wikipedia.org/wiki/Parent–offspring_conflict |
The Parflange F37 system is a technology from the hydraulic area of Parker-Hannifin , which allows a non welded flange connection of hydraulic tubes and pipes.
Use-orientated, the connection will be done by either flaring or retaining ring technology.
Flaring Technology After putting a F37 flange onto a seamless hydr... | https://en.wikipedia.org/wiki/Parflange_F37 |
The Parikh– Doering oxidation is an oxidation reaction that transforms primary and secondary alcohols into aldehydes and ketones , respectively. [ 1 ] The procedure uses dimethyl sulfoxide (DMSO) as the oxidant and the solvent, activated by the sulfur trioxide pyridine complex (SO 3 •C 5 H 5 N) in the presence of triet... | https://en.wikipedia.org/wiki/Parikh–Doering_oxidation |
Paris' law (also known as the Paris–Erdogan equation ) is a crack growth equation that gives the rate of growth of a fatigue crack. The stress intensity factor K {\displaystyle K} characterises the load around a crack tip and the rate of crack growth is experimentally shown to be a function of the range of stress inten... | https://en.wikipedia.org/wiki/Paris'_law |
Paris Métro Line 14 (French: Ligne 14 du métro de Paris ) is one of the sixteen lines on the Paris Métro . It connects Saint-Denis–Pleyel and Aéroport d'Orly on a north-west south-east diagonal via the three major stations of Gare Saint-Lazare , the Châtelet–Les-Halles complex , and Gare de Lyon . The line goes through... | https://en.wikipedia.org/wiki/Paris_Métro_Line_14 |
In molecular physics , the Pariser–Parr–Pople method applies semi-empirical quantum mechanical methods to the quantitative prediction of electronic structures and spectra, in molecules of interest in the field of organic chemistry . Previous methods existed—such as the Hückel method which led to Hückel's rule —but were... | https://en.wikipedia.org/wiki/Pariser–Parr–Pople_method |
In mathematical logic , the Paris–Harrington theorem states that a certain claim in Ramsey theory , namely the strengthened finite Ramsey theorem, which is expressible in Peano arithmetic , is not provable in this system. That Ramsey-theoretic claim is, however, provable in slightly stronger systems.
This result has b... | https://en.wikipedia.org/wiki/Paris–Harrington_theorem |
In coding theory , a parity-check matrix of a linear block code C is a matrix which describes the linear relations that the components of a codeword must satisfy. It can be used to decide whether a particular vector is a codeword and is also used in decoding algorithms.
Formally, a parity check matrix H of a linear co... | https://en.wikipedia.org/wiki/Parity-check_matrix |
In mathematics , parity is the property of an integer of whether it is even or odd . An integer is even if it is divisible by 2, and odd if it is not. [ 1 ] For example, −4, 0, and 82 are even numbers, while −3, 5, 23, and 69 are odd numbers.
The above definition of parity applies only to integer numbers, hence it can... | https://en.wikipedia.org/wiki/Parity_(mathematics) |
In physics , a parity transformation (also called parity inversion ) is the flip in the sign of one spatial coordinate . In three dimensions, it can also refer to the simultaneous flip in the sign of all three spatial coordinates (a point reflection ):
P : ( x y z ) ↦ ( − x − y − z ) . {\displaystyle \mathbf {P} :{\be... | https://en.wikipedia.org/wiki/Parity_(physics) |
A parity bit , or check bit , is a bit added to a string of binary code . Parity bits are a simple form of error detecting code . Parity bits are generally applied to the smallest units of a communication protocol, typically 8-bit octets (bytes), although they can also be applied separately to an entire message string ... | https://en.wikipedia.org/wiki/Parity_bit |
Parity measurement (also referred to as Operator measurement ) is a procedure in quantum information science used for error detection in quantum qubits. A parity measurement checks the equality of two qubits to return a true or false answer, which can be used to determine whether a correction needs to occur. [ 1 ] Addi... | https://en.wikipedia.org/wiki/Parity_measurement |
In mathematics , when X is a finite set with at least two elements, the permutations of X (i.e. the bijective functions from X to X ) fall into two classes of equal size: the even permutations and the odd permutations . If any total ordering of X is fixed, the parity ( oddness or evenness ) of a permutation σ {\display... | https://en.wikipedia.org/wiki/Parity_of_a_permutation |
The Park Grass Experiment is a biological study originally set up to test the effect of fertilizers and manures on hay yields . The scientific experiment is located at the Rothamsted Research in the English county of Hertfordshire , and is notable as one of the longest-running experiments of modern science, as it was i... | https://en.wikipedia.org/wiki/Park_Grass_Experiment |
Parkeol is a relatively uncommon sterol secondary metabolite found mostly in plants, particularly noted in Butyrospermum parkii (now called Vitellaria paradoxa , or the shea tree). [ 1 ] It can be synthesized as a minor product by several oxidosqualene cyclase enzymes , and is the sole product of the enzyme parkeol syn... | https://en.wikipedia.org/wiki/Parkeol |
The Parker variable wing is a wing configuration in biplane or triplane aircraft designed by H.F. Parker in 1920. [ 1 ] His design allows a supplement in lift while landing or taking-off.
The system is depicted in the figure. The figure shows the biplane configuration. The lower airfoil is rigid. The upper airfoil is f... | https://en.wikipedia.org/wiki/Parker_variable_wing |
In mathematics , especially the field of group theory , the Parker vector is an integer vector that describes a permutation group in terms of the cycle structure of its elements, defined by Richard A. Parker .
The Parker vector P of a permutation group G acting on a set of size n , is the vector whose k th component f... | https://en.wikipedia.org/wiki/Parker_vector |
Phosphate conversion coating is a chemical treatment applied to steel parts that creates a thin adhering layer of iron , zinc , or manganese phosphates to improve corrosion resistance or lubrication or as a foundation for subsequent coatings or painting. [ 1 ] [ 2 ] [ 3 ] It is one of the most common types of conversio... | https://en.wikipedia.org/wiki/Parkerizing |
In mathematics , the Parker–Sochacki method is an algorithm for solving systems of ordinary differential equations (ODEs), developed by G. Edgar Parker and James Sochacki , of the James Madison University Mathematics Department. The method produces Maclaurin series solutions to systems of differential equations, with t... | https://en.wikipedia.org/wiki/Parker–Sochacki_method |
The Parkes process is a pyrometallurgical industrial process for removing silver from lead during the production of bullion . It is an example of liquid–liquid extraction .
The process takes advantage of two liquid-state properties of zinc . The first is that zinc is immiscible with lead, and the other is that silver ... | https://en.wikipedia.org/wiki/Parkes_process |
Parking guidance and information ( PGI ) systems, or car park guidance systems , present drivers with dynamic information on parking within controlled areas. The systems combine traffic monitoring, communication, processing and variable message sign technologies to provide the service.
Modern parking lots utilize a va... | https://en.wikipedia.org/wiki/Parking_guidance_and_information |
The METU Parlar Foundation Science Award ( Turkish : ODTÜ Mustafa Parlar Ödülü ) is a science award issued by the Middle East Technical University Prof. Dr. Mustafa N. Parlar Foundation established in 1981 in Ankara , Turkey , commemorates Professor Mustafa N. Parlar , who served as the Dean of Engineering at the Middl... | https://en.wikipedia.org/wiki/Parlar_Foundation_Science_Award |
The Parliamentary Office of Science and Technology ( POST ) is an impartial research and knowledge exchange service based in the Parliament of the United Kingdom [ 1 ] POST serves both Houses of Parliament (the House of Commons and the House of Lords ).
It produces concise briefings focusing on topical issues where th... | https://en.wikipedia.org/wiki/Parliamentary_Office_of_Science_and_Technology |
Parrondo's paradox , a paradox in game theory , has been described as: A combination of losing strategies becomes a winning strategy . [ 1 ] It is named after its creator, Juan Parrondo , who discovered the paradox in 1996. A more explanatory description is:
Parrondo devised the paradox in connection with his analysis... | https://en.wikipedia.org/wiki/Parrondo's_paradox |
In mathematics , the Parry–Daniels map is a function studied in the context of dynamical systems . Typical questions concern the existence of an invariant or ergodic measure for the map. [ 1 ]
It is named after the English mathematician Bill Parry [ 2 ] and the British statistician Henry Daniels , [ 3 ] who independen... | https://en.wikipedia.org/wiki/Parry–Daniels_map |
In mathematics , the Parry–Sullivan invariant (or Parry–Sullivan number ) is a numerical quantity of interest in the study of incidence matrices in graph theory , and of certain one-dimensional dynamical systems . It provides a partial classification of non-trivial irreducible incidence matrices.
It is named after the... | https://en.wikipedia.org/wiki/Parry–Sullivan_invariant |
Pars destruens and pars construens (Latin) are complementary parts of argumentation . The negative part of criticizing views is the pars destruens . And the positive part of stating one's own position and arguments is the pars construens .
The distinction goes back to Francis Bacon and his work Novum Organum (1620). T... | https://en.wikipedia.org/wiki/Pars_destruens_and_pars_construens |
The parsec (symbol: pc ) is a unit of length used to measure the large distances to astronomical objects outside the Solar System , approximately equal to 3.26 light-years or 206,265 astronomical units (AU), i.e. 30.9 trillion kilometres (19.2 trillion miles ). [ a ] The parsec unit is obtained by the use of parallax a... | https://en.wikipedia.org/wiki/Parsec |
The Parshall flume is an open channel flow-metering device that was developed to measure the flow of surface water and irrigation flow. The Parshall flume is a modified version of the Venturi flume . Named after its creator, Dr. Ralph L. Parshall of the U.S. Soil Conservation Service , the Parshall flume is a fixed hyd... | https://en.wikipedia.org/wiki/Parshall_flume |
A part number (often abbreviated PN , P/N , part no. , or part # ) is an identifier of a particular part design or material used in a particular industry. Its purpose is to simplify reference that item. A part number unambiguously identifies a part design within a single corporation, sometimes across several corporatio... | https://en.wikipedia.org/wiki/Part_number |
Parthanatos (derived from the Greek Θάνατος, " Death ") is a form of programmed cell death that is distinct from other cell death processes such as necrosis and apoptosis . While necrosis is caused by acute cell injury resulting in traumatic cell death and apoptosis is a highly controlled process signalled by apoptotic... | https://en.wikipedia.org/wiki/Parthanatos |
In mathematics – and in particular the study of games on the unit square – Parthasarathy's theorem is a generalization of Von Neumann's minimax theorem . It states that a particular class of games has a mixed value, provided that at least one of the players has a strategy that is restricted to absolutely continuous di... | https://en.wikipedia.org/wiki/Parthasarathy's_theorem |
Parthenogenesis ( / ˌ p ɑːr θ ɪ n oʊ ˈ dʒ ɛ n ɪ s ɪ s , - θ ɪ n ə -/ ; [ 1 ] [ 2 ] from the Greek παρθένος , parthénos , 'virgin' + γένεσις , génesis , 'creation' [ 3 ] ) is a natural form of asexual reproduction in which the embryo develops directly from an egg without need for fertilization . In animals , parthenogen... | https://en.wikipedia.org/wiki/Parthenogenesis |
Partial-wave analysis , in the context of quantum mechanics , refers to a technique for solving scattering problems by decomposing each wave into its constituent angular-momentum components and solving using boundary conditions . Partial wave analysis is typically useful for low energy scattering where only a few angul... | https://en.wikipedia.org/wiki/Partial-wave_analysis |
In abstract algebra , a partial algebra is a generalization of universal algebra to partial operations . [ 1 ] [ 2 ]
There is a "Meta Birkhoff Theorem" by Andreka, Nemeti and Sain (1982). [ 1 ]
This algebra -related article is a stub . You can help Wikipedia by expanding it . | https://en.wikipedia.org/wiki/Partial_algebra |
In atomic physics , a partial charge (or net atomic charge ) is a non- integer charge value when measured in elementary charge units. It is represented by the Greek lowercase delta (𝛿), namely 𝛿− or 𝛿+.
Partial charges are created due to the asymmetric distribution of electrons in chemical bonds . For example, in a... | https://en.wikipedia.org/wiki/Partial_charge |
In the field of cell biology , the method of partial cloning ( PCL ) converts a fully differentiated old somatic cell into a partially reprogrammed young cell that retains all the specialised functions of the differentiated old cell but is simply younger. [ 1 ] The method of PCL reverses characteristics associated with... | https://en.wikipedia.org/wiki/Partial_cloning |
In theoretical computer science , an algorithm is correct with respect to a specification if it behaves as specified. Best explored is functional correctness, which refers to the input–output behavior of the algorithm: for each input it produces an output satisfying the specification. [ 1 ]
Within the latter notion, p... | https://en.wikipedia.org/wiki/Partial_correctness |
In graph theory , a partial cube is a graph that is an isometric subgraph of a hypercube . [ 1 ] In other words, a partial cube can be identified with a subgraph of a hypercube in such a way that the distance between any two vertices in the partial cube is the same as the distance between those vertices in the hypercub... | https://en.wikipedia.org/wiki/Partial_cube |
In electrochemistry , partial current is defined as the electric current associated with ( anodic or cathodic ) half of the electrode reaction .
Depending on the electrode half-reaction, one can distinguish two types of partial current:
The cathodic and anodic partial currents are defined by IUPAC . [ 1 ]
The partia... | https://en.wikipedia.org/wiki/Partial_current |
In mathematics, a partial cyclic order is a ternary relation that generalizes a cyclic order in the same way that a partial order generalizes a linear order .
Over a given set, a partial cyclic order is a ternary relation R {\displaystyle R} that is:
Direct sum
Direct product
Power [ 2 ] [ 3 ]
Dedekind–MacNeille c... | https://en.wikipedia.org/wiki/Partial_cyclic_order |
In mathematics , a partial derivative of a function of several variables is its derivative with respect to one of those variables, with the others held constant (as opposed to the total derivative , in which all variables are allowed to vary). Partial derivatives are used in vector calculus and differential geometry .
... | https://en.wikipedia.org/wiki/Partial_derivative |
In mathematics a partial differential algebraic equation (PDAE) set is an incomplete system of partial differential equations that is closed with a set of algebraic equations .
A general PDAE is defined as:
where:
The relationship between a PDAE and a partial differential equation (PDE) is analogous to the relations... | https://en.wikipedia.org/wiki/Partial_differential_algebraic_equation |
In mathematics , a partial differential equation ( PDE ) is an equation which involves a multivariable function and one or more of its partial derivatives .
The function is often thought of as an "unknown" that solves the equation, similar to how x is thought of as an unknown number solving, e.g., an algebraic equatio... | https://en.wikipedia.org/wiki/Partial_differential_equation |
In materials science , a partial dislocation is a decomposed form of dislocation that occurs within a crystalline material. An extended dislocation is a dislocation that has dissociated into a pair of partial dislocations. The vector sum of the Burgers vectors of the partial dislocations is the Burgers vector of the ex... | https://en.wikipedia.org/wiki/Partial_dislocation |
In genetics , the partial dominance hypothesis states that inbreeding depression is the result of the frequency increase of homozygous deleterious recessive or partially recessive alleles . The hypothesis can be explained by looking at a population that is divided into a large number of separately inbred lines. Deleter... | https://en.wikipedia.org/wiki/Partial_dominance_hypothesis |
In mathematics , a partial function f from a set X to a set Y is a function from a subset S of X (possibly the whole X itself) to Y . The subset S , that is, the domain of f viewed as a function, is called the domain of definition or natural domain of f . If S equals X , that is, if f is defined on every element in X ,... | https://en.wikipedia.org/wiki/Partial_function |
In abstract algebra , a partial groupoid (also called halfgroupoid , pargoid , or partial magma ) is a set endowed with a partial binary operation . [ 1 ] [ 2 ]
A partial groupoid is a partial algebra .
A partial groupoid ( G , ∘ ) {\displaystyle (G,\circ )} is called a partial semigroup if the following associative ... | https://en.wikipedia.org/wiki/Partial_groupoid |
Partial Information Decomposition is an extension of information theory , that aims to generalize the pairwise relations described by information theory to the interaction of multiple variables. [ 1 ]
Information theory can quantify the amount of information a single source variable X 1 {\displaystyle X_{1}} has about... | https://en.wikipedia.org/wiki/Partial_information_decomposition |
A partial linear space (also semilinear or near-linear space) is a basic incidence structure in the field of incidence geometry, that carries slightly less structure than a linear space .
The notion is equivalent to that of a linear hypergraph .
Let S = ( P , L , I ) {\displaystyle S=({\mathcal {P}},{\mathcal {L}},{\t... | https://en.wikipedia.org/wiki/Partial_linear_space |
In thermodynamics , a partial molar property is a quantity which describes the variation of an extensive property of a solution or mixture with changes in the molar composition of the mixture at constant temperature and pressure . It is the partial derivative of the extensive property with respect to the amount (number... | https://en.wikipedia.org/wiki/Partial_molar_property |
Partial oxidation ( POX ) is a type of chemical reaction . It occurs when a substoichiometric fuel-air mixture is partially combusted in a reformer, creating a hydrogen-rich syngas which can then be put to further use, for example in a fuel cell . A distinction is made between thermal partial oxidation (TPOX) and catal... | https://en.wikipedia.org/wiki/Partial_oxidation |
In combinatorial mathematics , a partial permutation , or sequence without repetition , on a finite set S is a bijection between two specified subsets of S . That is, it is defined by two subsets U and V of equal size, and a one-to-one mapping from U to V . Equivalently, it is a partial function on S that can be extend... | https://en.wikipedia.org/wiki/Partial_permutation |
In a mixture of gases , each constituent gas has a partial pressure which is the notional pressure of that constituent gas as if it alone occupied the entire volume of the original mixture at the same temperature . [ 1 ] The total pressure of an ideal gas mixture is the sum of the partial pressures of the gases in the... | https://en.wikipedia.org/wiki/Partial_pressure |
The grid method (also known as the box method or matrix method ) of multiplication is an introductory approach to multi-digit multiplication calculations that involve numbers larger than ten. Because it is often taught in mathematics education at the level of primary school or elementary school , this algorithm is some... | https://en.wikipedia.org/wiki/Partial_products_algorithm |
The partial specific volume v i ¯ , {\displaystyle {\bar {v_{i}}},} express the variation of the extensive volume of a mixture in respect to composition of the masses. It is the partial derivative of volume with respect to the mass of the component of interest.
where v i ¯ {\displaystyle {\bar {v_{i}}}} is the partial... | https://en.wikipedia.org/wiki/Partial_specific_volume |
Partial stroke testing (or PST) is a technique used in a control system to allow the user to test a percentage of the possible failure modes of a shut down valve without the need to physically close the valve. PST is used to assist in determining that the safety function will operate on demand. PST is most often used o... | https://en.wikipedia.org/wiki/Partial_stroke_testing |
In linear algebra and functional analysis , the partial trace is a generalization of the trace . Whereas the trace is a scalar -valued function on operators, the partial trace is an operator -valued function. The partial trace has applications in quantum information and decoherence which is relevant for quantum measu... | https://en.wikipedia.org/wiki/Partial_trace |
In abstract algebra , a partially ordered group is a group ( G , +) equipped with a partial order "≤" that is translation-invariant ; in other words, "≤" has the property that, for all a , b , and g in G , if a ≤ b then a + g ≤ b + g and g + a ≤ g + b .
An element x of G is called positive if 0 ≤ x . The set of elemen... | https://en.wikipedia.org/wiki/Partially_ordered_group |
All definitions tacitly require the homogeneous relation R {\displaystyle R} be transitive : for all a , b , c , {\displaystyle a,b,c,} if a R b {\displaystyle aRb} and b R c {\displaystyle bRc} then a R c . {\displaystyle aRc.} A term's definition may require additional properties that are not listed in this table.
I... | https://en.wikipedia.org/wiki/Partially_ordered_set |
Partially premixed combustion (PPC), also known as PPCI (partially-premixed compression ignition) or GDCI (gasoline direct-injection compression-ignition) [ 1 ] [ 2 ] [ 3 ] [ 4 ] is a modern combustion process intended to be used in internal combustion engines of automobiles and other motorized vehicles in the future. ... | https://en.wikipedia.org/wiki/Partially_premixed_combustion |
Participatory design (originally co-operative design , now often co-design ) is an approach to design attempting to actively involve all stakeholders (e.g. employees, partners, customers, citizens, end users) in the design process to help ensure the result meets their needs and is usable . Participatory design is an ap... | https://en.wikipedia.org/wiki/Participatory_design |
Particle-Induced X-Ray Emission or Proton-Induced X-Ray Emission ( PIXE ) is a technique used for determining the elemental composition of a material or a sample . When a material is exposed to an ion beam, atomic interactions occur that give off EM radiation of wavelengths in the x-ray part of the electromagnetic spec... | https://en.wikipedia.org/wiki/Particle-induced_X-ray_emission |
Particle-laden flows refers to a class of two-phase fluid flow , in which one of the phases is continuously connected (referred to as the continuous or carrier phase) and the other phase is made up of small, immiscible, and typically dilute particles (referred to as the dispersed or particle phase). Fine aerosol partic... | https://en.wikipedia.org/wiki/Particle-laden_flow |
In granulometry , the particle-size distribution ( PSD ) of a powder , or granular material , or particles dispersed in fluid , is a list of values or a mathematical function that defines the relative amount, typically by mass , of particles present according to size. [ 1 ] Significant energy is usually required to dis... | https://en.wikipedia.org/wiki/Particle-size_distribution |
In marine and freshwater ecology , a particle is a small object. Particles can remain in suspension in the ocean or freshwater. However, they eventually settle (rate determined by Stokes' law ) and accumulate as sediment. Some can enter the atmosphere through wave action where they can act as cloud condensation nuclei ... | https://en.wikipedia.org/wiki/Particle_(ecology) |
The Particle Astrophysics Magnet Facility (commonly known as ASTROMAG) is a NASA project that was designed to investigate anti-matter. It consisted of a series of experiments which would culminate in an experiment launched in 1995 to be externally attached to the Freedom Space Station
Experiments and postulation condu... | https://en.wikipedia.org/wiki/Particle_Astrophysics_Magnet_Facility |
The Particle Data Group ( PDG ) is an international collaboration of particle physicists that compiles and reanalyzes published results related to the properties of particles and fundamental interactions . It also publishes reviews of theoretical results that are phenomenologically relevant, including those in related... | https://en.wikipedia.org/wiki/Particle_Data_Group |
Particle agglomeration refers to the formation of assemblages in a suspension and represents a mechanism leading to the functional destabilization of colloidal systems. During this process, particles dispersed in the liquid phase stick to each other , and spontaneously form irregular particle assemblages, flocs, or agg... | https://en.wikipedia.org/wiki/Particle_aggregation |
Particle chauvinism is the term used by British astrophysicist Martin Rees to describe the (allegedly erroneous) assumption that what we think of as normal matter – atoms , quarks , electrons , etc. (excluding dark matter or other matter) – is the basis of matter in the universe, rather than a rare phenomenon. [ 1 ]
W... | https://en.wikipedia.org/wiki/Particle_chauvinism |
Particle damping is the use of particles moving freely in a cavity to produce a damping effect.
Active and passive damping techniques are common methods of attenuating the resonant vibrations excited in a structure. Active damping techniques are not applicable under all circumstances due, for example, to power require... | https://en.wikipedia.org/wiki/Particle_damping |
In particle physics , particle decay is the spontaneous process of one unstable subatomic particle transforming into multiple other particles. The particles created in this process (the final state ) must each be less massive than the original, although the total mass of the system must be conserved. A particle is unst... | https://en.wikipedia.org/wiki/Particle_decay |
Particle deposition is the spontaneous attachment of particles to surfaces. The particles in question are normally colloidal particles , while the surfaces involved may be planar, curved, or may represent particles much larger in size than the depositing ones (e.g., sand grains). Deposition processes may be triggered b... | https://en.wikipedia.org/wiki/Particle_deposition |
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