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In computer science, algorithmic efficiency is a property of an algorithm which relates to the amount of computational resources used by the algorithm. Algorithmic efficiency can be thought of as analogous to engineering productivity for a repeating or continuous process.
For maximum efficiency it is desirable to minim... | https://en.wikipedia.org/wiki/Algorithmic_efficiency |
A hybrid algorithm is an algorithm that combines two or more other algorithms that solve the same problem, either choosing one based on some characteristic of the data, or switching between them over the course of the algorithm. This is generally done to combine desired features of each, so that the overall algorithm i... | https://en.wikipedia.org/wiki/Hybrid_algorithm |
Bead sort, also called gravity sort, is a natural sorting algorithm, developed by Joshua J. Arulanandham, Cristian S. Calude and Michael J. Dinneen in 2002, and published in The Bulletin of the European Association for Theoretical Computer Science. Both digital and analog hardware implementations of bead sort can achi... | https://en.wikipedia.org/wiki/Bead_sort |
In computer vision, speeded up robust features (SURF) is a local feature detector and descriptor, with patented applications. It can be used for tasks such as object recognition, image registration, classification, or 3D reconstruction. It is partly inspired by the scale-invariant feature transform (SIFT) descriptor. T... | https://en.wikipedia.org/wiki/Speeded_up_robust_features |
The Robinson projection is a map projection of a world map that shows the entire world at once. It was specifically created in an attempt to find a good compromise to the problem of readily showing the whole globe as a flat image.
The Robinson projection was devised by Arthur H. Robinson in 1963 in response to an appea... | https://en.wikipedia.org/wiki/Robinson_projection |
In mathematics, a pointed set (also based set or rooted set) is an ordered pair
$$
(X, x_0)
$$
where
$$
X
$$
is a set and
$$
x_0
$$
is an element of
$$
X
$$
called the base point (also spelled basepoint).
Maps between pointed sets
$$
(X, x_0)
$$
and
$$
(Y, y_0)
$$
—called based maps, pointed maps, or point-... | https://en.wikipedia.org/wiki/Pointed_set |
{{DISPLAYTITLE:Exotic R4}}
In mathematics, an exotic
$$
\R^4
$$
is a differentiable manifold that is homeomorphic (i.e. shape preserving) but not diffeomorphic (i.e. non smooth) to the Euclidean space
$$
\R^4.
$$
The first examples were found in 1982 by Michael Freedman and others, by using the contrast between Fre... | https://en.wikipedia.org/wiki/Exotic_R4 |
In computer programming, a dope vector is a data structure used to hold information about a data object, especially its memory layout.
## Purpose
Dope vectors are most commonly used to describe arrays, which commonly store multiple instances of a particular datatype as a contiguous block of memory. For example, an arra... | https://en.wikipedia.org/wiki/Dope_vector |
In logic and related fields such as mathematics and philosophy, "if and only if" (often shortened as "iff") is paraphrased by the biconditional, a logical connective between statements. The biconditional is true in two cases, where either both statements are true or both are false. The connective is biconditional (a s... | https://en.wikipedia.org/wiki/If_and_only_if |
In fluid dynamics, gravity waves are waves in a fluid medium or at the interface between two media when the force of gravity or buoyancy tries to restore equilibrium. An example of such an interface is that between the atmosphere and the ocean, which gives rise to wind waves.
A gravity wave results when fluid is displa... | https://en.wikipedia.org/wiki/Gravity_wave |
In mathematics a topological space is called countably compact if every countable open cover has a finite subcover.
## Equivalent definitions
A topological space X is called countably compact if it satisfies any of the following equivalent conditions:
(1) Every countable open cover of X has a finite subcover.
(2) Every... | https://en.wikipedia.org/wiki/Countably_compact_space |
In physics and materials science, elasticity is the ability of a body to resist a distorting influence and to return to its original size and shape when that influence or force is removed. Solid objects will deform when adequate loads are applied to them; if the material is elastic, the object will return to its initia... | https://en.wikipedia.org/wiki/Elasticity_%28physics%29 |
Connected-component labeling (CCL), connected-component analysis (CCA), blob extraction, region labeling, blob discovery, or region extraction is an algorithmic application of graph theory, where subsets of connected components are uniquely labeled based on a given heuristic. Connected-component labeling is not to be c... | https://en.wikipedia.org/wiki/Connected-component_labeling |
A sink (also known as basin in the UK) is a bowl-shaped plumbing fixture for washing hands, dishwashing, and other purposes. Sinks have a tap (faucet) that supplies hot and cold water and may include a spray feature to be used for faster rinsing. They also include a drain to remove used water; this drain may itself inc... | https://en.wikipedia.org/wiki/Sink |
C# (pronounced: C-sharp) ( ) is a general-purpose high-level programming language supporting multiple paradigms. C# encompasses static typing, strong typing, lexically scoped, imperative, declarative, functional, generic, object-oriented (class-based), and component-oriented programming disciplines.
The principal inven... | https://en.wikipedia.org/wiki/C_Sharp_%28programming_language%29 |
A digital signature is a mathematical scheme for verifying the authenticity of digital messages or documents. A valid digital signature on a message gives a recipient confidence that the message came from a sender known to the recipient.
Digital signatures are a standard element of most cryptographic protocol suites, a... | https://en.wikipedia.org/wiki/Digital_signature |
A rack and pinion is a type of linear actuator that comprises a circular gear (the pinion) engaging a linear gear (the rack). Together, they convert between rotational motion and linear motion: rotating the pinion causes the rack to be driven in a line. Conversely, moving the rack linearly will cause the pinion to rota... | https://en.wikipedia.org/wiki/Rack_and_pinion |
In mathematics, a transcendental function is an analytic function that does not satisfy a polynomial equation whose coefficients are functions of the independent variable that can be written using only the basic operations of addition, subtraction, multiplication, and division (without the need of taking limits). This ... | https://en.wikipedia.org/wiki/Transcendental_function |
Seismic inversion involves the set of methods which seismologists use to infer properties through physical measurements. Surface-wave inversion is the method by which elastic properties, density, and thickness of layers in the subsurface are obtained through analysis of surface-wave dispersion. The entire inversion p... | https://en.wikipedia.org/wiki/Surface_wave_inversion |
Algebraic combinatorics is an area of mathematics that employs methods of abstract algebra, notably group theory and representation theory, in various combinatorial contexts and, conversely, applies combinatorial techniques to problems in algebra.
## History
The term "algebraic combinatorics" was introduced in the late... | https://en.wikipedia.org/wiki/Algebraic_combinatorics |
Lubrication is the process or technique of using a lubricant to reduce friction and wear and tear in a contact between two surfaces. The study of lubrication is a discipline in the field of tribology.
## Lubrication mechanisms
such as fluid-lubricated systems are designed so that the applied load is partially or compl... | https://en.wikipedia.org/wiki/Lubrication |
In the mathematical field of combinatorics, given a collection
$$
\mathcal{S}
$$
of subsets of a set
$$
X
$$
, an exact cover is a subcollection
$$
\mathcal{S}^{*}
$$
of
$$
\mathcal{S}
$$
such that each element in
$$
X
$$
is contained in exactly one subset in
$$
\mathcal{S}^{*}
$$
.
One says that each element... | https://en.wikipedia.org/wiki/Exact_cover |
In mathematics, in the area of complex analysis, Nachbin's theorem (named after Leopoldo Nachbin) is a result used to establish bounds on the growth rates for analytic functions. In particular, Nachbin's theorem may be used to give the domain of convergence of the generalized Borel transform, also called
## Nachbin su... | https://en.wikipedia.org/wiki/Nachbin%27s_theorem |
Seasonal subseries plots are a graphical tool to visualize and detect seasonality in a time series. Seasonal subseries plots involves the extraction of the seasons from a time series into a subseries. Based on a selected periodicity, it is an alternative plot that emphasizes the seasonal patterns are where the data for... | https://en.wikipedia.org/wiki/Seasonal_subseries_plot |
The Touchard polynomials, studied by , also called the exponential polynomials or Bell polynomials, comprise a polynomial sequence of binomial type defined by
$$
T_n(x)=\sum_{k=0}^n S(n,k)x^k=\sum_{k=0}^n
\left\{ {n \atop k} \right\}x^k,
$$
where
$$
S(n,k)=\left\{ {n \atop k} \right\}
$$
is a Stirling number of the s... | https://en.wikipedia.org/wiki/Touchard_polynomials |
In computer programming, the exclusive or swap (sometimes shortened to XOR swap) is an algorithm that uses the exclusive or bitwise operation to swap the values of two variables without using the temporary variable which is normally required.
## The algorithm
is primarily a novelty and a way of demonstrating propertie... | https://en.wikipedia.org/wiki/XOR_swap_algorithm |
In biochemistry, a Ramachandran plot (also known as a Rama plot, a Ramachandran diagram or a [φ,ψ] plot), originally developed in 1963 by G. N. Ramachandran, C. Ramakrishnan, and V. Sasisekharan, is a way to visualize energetically allowed regions for backbone dihedral angles (also called as torsional angles, phi and p... | https://en.wikipedia.org/wiki/Ramachandran_plot |
In audio signal processing and acoustics, an echo is a reflection of sound that arrives at the listener with a delay after the direct sound. The delay is directly proportional to the distance of the reflecting surface from the source and the listener. Typical examples are the echo produced by the bottom of a well, a bu... | https://en.wikipedia.org/wiki/Echo |
The speed of sound is the distance travelled per unit of time by a sound wave as it propagates through an elastic medium. More simply, the speed of sound is how fast vibrations travel. At , the speed of sound in air is about , or in or one mile in . It depends strongly on temperature as well as the medium through whi... | https://en.wikipedia.org/wiki/Speed_of_sound |
A seismometer is an instrument that responds to ground displacement and shaking such as caused by quakes, volcanic eruptions, and explosions. They are usually combined with a timing device and a recording device to form a seismograph. The output of such a device—formerly recorded on paper (see picture) or film, now rec... | https://en.wikipedia.org/wiki/Seismometer |
In algorithmic information theory (a subfield of computer science and mathematics), the Kolmogorov complexity of an object, such as a piece of text, is the length of a shortest computer program (in a predetermined programming language) that produces the object as output. It is a measure of the computational resources n... | https://en.wikipedia.org/wiki/Kolmogorov_complexity |
In general relativity, the metric tensor (in this context often abbreviated to simply the metric) is the fundamental object of study. The metric captures all the geometric and causal structure of spacetime, being used to define notions such as time, distance, volume, curvature, angle, and separation of the future and t... | https://en.wikipedia.org/wiki/Metric_tensor_%28general_relativity%29 |
##
This is about lattice theory. For other similarly named results, see
## Birkhoff's theorem
(disambiguation).
In mathematics, Birkhoff's representation theorem for distributive lattices states that the elements of any finite distributive lattice can be represented as finite sets, in such a way that the lattice ope... | https://en.wikipedia.org/wiki/Birkhoff%27s_representation_theorem |
How to Solve It (1945) is a small volume by mathematician George Pólya, describing methods of problem solving.
This book has remained in print continually since 1945.
## Four principles
How to Solve It suggests the following steps when solving a mathematical problem:
1. First, you have to understand the problem.
1. Af... | https://en.wikipedia.org/wiki/How_to_Solve_It |
In computer science, mutual exclusion is a property of concurrency control, which is instituted for the purpose of preventing race conditions. It is the requirement that one thread of execution never enters a critical section while a concurrent thread of execution is already accessing said critical section, which refer... | https://en.wikipedia.org/wiki/Mutual_exclusion |
+ Play golf dataset Independent variables Dep. var Outlook Temperature Humidity Windy Playsunny 85 85 FALSE Don't play sunny 80 90 TRUE Don't playovercast 83 78 FALSE Playrain 70 96 FALSE Playrain 68 80 FALSE Playrain 65 70 TRUE Don't playovercast 64 65 TRUE Playsunny 72 95 FALSE Don... | https://en.wikipedia.org/wiki/Decision_table |
In computer programming, a block or code block or block of code is a lexical structure of source code which is grouped together. Blocks consist of one or more declarations and statements. A programming language that permits the creation of blocks, including blocks nested within other blocks, is called a block-structure... | https://en.wikipedia.org/wiki/Block_%28programming%29 |
In computer science, a disjoint-set data structure, also called a union–find data structure or merge–find set, is a data structure that stores a collection of disjoint (non-overlapping) sets. Equivalently, it stores a partition of a set into disjoint subsets. It provides operations for adding new sets, merging sets (re... | https://en.wikipedia.org/wiki/Disjoint-set_data_structure |
An optical prism is a transparent optical element with flat, polished surfaces that are designed to refract light. At least one surface must be angled — elements with two parallel surfaces are not prisms. The most familiar type of optical prism is the triangular prism, which has a triangular base and rectangular sides.... | https://en.wikipedia.org/wiki/Prism_%28optics%29 |
In mathematics, the complex conjugate of a complex number is the number with an equal real part and an imaginary part equal in magnitude but opposite in sign. That is, if
$$
a
$$
and
$$
b
$$
are real numbers, then the complex conjugate of
$$
a + bi
$$
is
$$
a - bi.
$$
The complex conjugate of
$$
z
$$
is oft... | https://en.wikipedia.org/wiki/Complex_conjugate |
GTK (formerly GIMP ToolKit and GTK+) is a free software cross-platform widget toolkit for creating graphical user interfaces (GUIs). It is licensed under the terms of the GNU Lesser General Public License, allowing both free and proprietary software to use it. It is one of the most popular toolkits for the Wayland and ... | https://en.wikipedia.org/wiki/GTK |
Marine engineering is the engineering of boats, ships, submarines, and any other marine vessel. Here it is also taken to include the engineering of other ocean systems and structures – referred to in certain academic and professional circles as "ocean engineering". After completing this degree one can join a ship as an... | https://en.wikipedia.org/wiki/Marine_engineering |
In graph theory and computer science, the lowest common ancestor (LCA) (also called least common ancestor) of two nodes and in a tree or directed acyclic graph (DAG) is the lowest (i.e. deepest) node that has both and as descendants, where we define each node to be a descendant of itself (so if has a direct conn... | https://en.wikipedia.org/wiki/Lowest_common_ancestor |
A hash array mapped trie (HAMT) is an implementation of an associative array that combines the characteristics of a hash table and an array mapped trie.
It is a refined version of the more general notion of a hash tree.
## Operation
A HAMT is an array mapped trie where the keys are first hashed to ensure an even distri... | https://en.wikipedia.org/wiki/Hash_array_mapped_trie |
In number theory and algebraic geometry, a rational point of an algebraic variety is a point whose coordinates belong to a given field. If the field is not mentioned, the field of rational numbers is generally understood. If the field is the field of real numbers, a rational point is more commonly called a real point. ... | https://en.wikipedia.org/wiki/Rational_point |
A slow-wave potential is a rhythmic electrophysiological event in the gastrointestinal tract. The normal conduction of slow waves is one of the key regulators of gastrointestinal motility. Slow waves are generated and propagated by a class of pacemaker cells called the interstitial cells of Cajal, which also act as int... | https://en.wikipedia.org/wiki/Slow-wave_potential |
The American Association for the Advancement of Science (AAAS) is a United States–based international nonprofit with the stated mission of promoting cooperation among scientists, defending scientific freedom, encouraging scientific responsibility, and supporting scientific education and science outreach for the betterm... | https://en.wikipedia.org/wiki/American_Association_for_the_Advancement_of_Science |
In set theory, Kőnig's theorem states that if the axiom of choice holds, I is a set,
$$
\kappa_i
$$
and
$$
\lambda_i
$$
are cardinal numbers for every i in I, and
$$
\kappa_i < \lambda_i
$$
for every i in I, then
$$
\sum_{i \in I}\kappa_i < \prod_{i \in I}\lambda_i.
$$
The sum here is the cardinality of the dis... | https://en.wikipedia.org/wiki/K%C5%91nig%27s_theorem_%28set_theory%29 |
In mathematics, a quartic equation is one which can be expressed as a quartic function equaling zero. The general form of a quartic equation is
$$
ax^4+bx^3+cx^2+dx+e=0 \,
$$
where a ≠ 0.
The quartic is the highest order polynomial equation that can be solved by radicals in the general case.
## History
Lodovico Ferrari... | https://en.wikipedia.org/wiki/Quartic_equation |
Ramsey theory, named after the British mathematician and philosopher Frank P. Ramsey, is a branch of the mathematical field of combinatorics that focuses on the appearance of order in a substructure given a structure of a known size. Problems in Ramsey theory typically ask a question of the form: "how big must some str... | https://en.wikipedia.org/wiki/Ramsey_theory |
Echo sounding or depth sounding is the use of sonar for ranging, normally to determine the depth of water (bathymetry). It involves transmitting acoustic waves into water and recording the time interval between emission and return of a pulse; the resulting time of flight, along with knowledge of the speed of sound in w... | https://en.wikipedia.org/wiki/Echo_sounding |
Photonics is a branch of optics that involves the application of generation, detection, and manipulation of light in the form of photons through emission, transmission, modulation, signal processing, switching, amplification, and sensing. Even though photonics is a commonly used term, there is no widespread agreement o... | https://en.wikipedia.org/wiki/Photonics |
In electrodynamics, Poynting's theorem is a statement of conservation of energy for electromagnetic fields that was developed by British physicist John Henry Poynting. It states that in a given volume, the stored energy changes at a rate given by the work done on the charges within the volume, minus the rate at which e... | https://en.wikipedia.org/wiki/Poynting%27s_theorem |
The approximate counting algorithm allows the counting of a large number of events using a small amount of memory. Invented in 1977 by Robert Morris of Bell Labs, it uses probabilistic techniques to increment the counter. It was fully analyzed in the early 1980s by Philippe Flajolet of INRIA Rocquencourt, who coined ... | https://en.wikipedia.org/wiki/Approximate_counting_algorithm |
Viviani's theorem, named after Vincenzo Viviani, states that the sum of the shortest distances from any interior point to the sides of an equilateral triangle equals the length of the triangle's altitude. It is a theorem commonly employed in various math competitions, secondary school mathematics examinations, and has ... | https://en.wikipedia.org/wiki/Viviani%27s_theorem |
In quantum mechanics, Kramers' theorem or Kramers' degeneracy theorem states that for every energy eigenstate of a time-reversal symmetric system with half-integer total spin, there is another eigenstate with the same energy related by time-reversal. In other words, the degeneracy of every energy level is an even numbe... | https://en.wikipedia.org/wiki/Kramers%27_theorem |
In game theory, the unscrupulous diner's dilemma (or just diner's dilemma) is an n-player prisoner's dilemma. The situation imagined is that several people go out to eat, and before ordering, they agree to split the cost equally between them. Each diner must now choose whether to order the costly or cheap dish. It is p... | https://en.wikipedia.org/wiki/Unscrupulous_diner%27s_dilemma |
In computer science, locality-sensitive hashing (LSH) is a fuzzy hashing technique that hashes similar input items into the same "buckets" with high probability. (The number of buckets is much smaller than the universe of possible input items.) Since similar items end up in the same buckets, this technique can be used ... | https://en.wikipedia.org/wiki/Locality-sensitive_hashing |
The Pandya theorem is a good illustration of the richness of information forthcoming from a judicious use of subtle symmetry principles connecting vastly different sectors of nuclear systems. It is a tool for calculations regarding both particles and holes.
## Description
Pandya theorem provides a theoretical framework... | https://en.wikipedia.org/wiki/Pandya_theorem |
In physics, symmetry breaking is a phenomenon where a disordered but symmetric state collapses into an ordered, but less symmetric state. This collapse is often one of many possible bifurcations that a particle can take as it approaches a lower energy state. Due to the many possibilities, an observer may assume the res... | https://en.wikipedia.org/wiki/Symmetry_breaking |
An aircraft ( aircraft) is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or the dynamic lift of an airfoil, or, in a few cases, direct downward thrust from its engines. Common examples of aircraft include airplanes, rotorcraft (including heli... | https://en.wikipedia.org/wiki/Aircraft |
In game theory, the best response is the strategy (or strategies) which produces the most favorable outcome for a player, taking other players' strategies as given. The concept of a best response is central to John Nash's best-known contribution, the Nash equilibrium, the point at which each player in a game has select... | https://en.wikipedia.org/wiki/Best_response |
In computer programming, especially functional programming and type theory, an algebraic data type (ADT) is a kind of composite data type, i.e., a data type formed by combining other types.
Two common classes of algebraic types are product types (i.e., tuples, and records) and sum types (i.e., tagged or disjoint unions... | https://en.wikipedia.org/wiki/Algebraic_data_type |
In the mathematical field of graph theory, Fáry's theorem states that any simple, planar graph can be drawn without crossings so that its edges are straight line segments. That is, the ability to draw graph edges as curves instead of as straight line segments does not allow a larger class of graphs to be drawn. The th... | https://en.wikipedia.org/wiki/F%C3%A1ry%27s_theorem |
In mathematics, more specifically in abstract algebra, the Frobenius theorem, proved by Ferdinand Georg Frobenius in 1877, characterizes the finite-dimensional associative division algebras over the real numbers. According to the theorem, every such algebra is isomorphic to one of the following:
- (the real numbers)
... | https://en.wikipedia.org/wiki/Frobenius_theorem_%28real_division_algebras%29 |
In mathematics, Gaussian measure is a Borel measure on finite-dimensional Euclidean space
$$
R^n
$$
, closely related to the normal distribution in statistics. There is also a generalization to infinite-dimensional spaces. Gaussian measures are named after the German mathematician Carl Friedrich Gauss. One reason why ... | https://en.wikipedia.org/wiki/Gaussian_measure |
In vector calculus and differential geometry the generalized Stokes theorem (sometimes with apostrophe as Stokes' theorem or Stokes's theorem), also called the Stokes–Cartan theorem, is a statement about the integration of differential forms on manifolds, which both simplifies and generalizes several theorems from vect... | https://en.wikipedia.org/wiki/Generalized_Stokes_theorem |
In mathematics, specifically in complex analysis, Fatou's theorem, named after Pierre Fatou, is a statement concerning holomorphic functions on the unit disk and their pointwise extension to the boundary of the disk.
## Motivation and statement of theorem
If we have a holomorphic function
$$
f
$$
defined on the open ... | https://en.wikipedia.org/wiki/Fatou%27s_theorem |
In oceanography, sea state is the general condition of the free surface on a large body of water—with respect to wind waves and swell—at a certain location and moment. A sea state is characterized by statistics, including the wave height, period, and spectrum. The sea state varies with time, as the wind and swell condi... | https://en.wikipedia.org/wiki/Sea_state |
The Sellmeier equation is an empirical relationship between refractive index and wavelength for a particular transparent medium. The equation is used to determine the dispersion of light in the medium.
It was first proposed in 1872 by Wolfgang Sellmeier and was a development of the work of Augustin Cauchy on Cauchy's e... | https://en.wikipedia.org/wiki/Sellmeier_equation |
The vehicle routing problem (VRP) is a combinatorial optimization and integer programming problem which asks "What is the optimal set of routes for a fleet of vehicles to traverse in order to deliver to a given set of customers?" It generalises the travelling salesman problem (TSP). It first appeared in a paper by Geor... | https://en.wikipedia.org/wiki/Vehicle_routing_problem |
In mathematics, homotopy theory is a systematic study of situations in which maps can come with homotopies between them. It originated as a topic in algebraic topology, but nowadays is learned as an independent discipline.
## Applications to other fields of mathematics
Besides algebraic topology, the theory has also be... | https://en.wikipedia.org/wiki/Homotopy_theory |
In science and engineering, the weight of an object is a quantity associated with the gravitational force exerted on the object by other objects in its environment, although there is some variation and debate as to the exact definition.
Some standard textbooks define weight as a vector quantity, the gravitational force... | https://en.wikipedia.org/wiki/Weight |
Probabilistic encryption is the use of randomness in an encryption algorithm, so that when encrypting the same message several times it will, in general, yield different ciphertexts. The term "probabilistic encryption" is typically used in reference to public key encryption algorithms; however various symmetric key en... | https://en.wikipedia.org/wiki/Probabilistic_encryption |
The growth–share matrix (also known as the product portfolio matrix, Boston Box, BCG-matrix, Boston matrix, Boston Consulting Group portfolio analysis and portfolio diagram) is a matrix used to help corporations to analyze their business units, that is, their product lines.
The matrix was initially created in a collab... | https://en.wikipedia.org/wiki/Growth%E2%80%93share_matrix |
Blondel's theorem, named after its discoverer, French electrical engineer André Blondel, is the result of his attempt to simplify both the measurement of electrical energy and the validation of such measurements.
The result is a simple rule that specifies the minimum number of watt-hour meters required to measure the... | https://en.wikipedia.org/wiki/Blondel%27s_theorem |
Psychophysics is the field of psychology which quantitatively investigates the relationship between physical stimuli and the sensations and perceptions they produce. Psychophysics has been described as "the scientific study of the relation between stimulus and sensation" or, more completely, as "the analysis of percept... | https://en.wikipedia.org/wiki/Psychophysics |
A rectilinear polygon is a polygon all of whose sides meet at right angles. Thus the interior angle at each vertex is either 90° or 270°. Rectilinear polygons are a special case of isothetic polygons.
In many cases another definition is preferable: a rectilinear polygon is a polygon with sides parallel to the axes of... | https://en.wikipedia.org/wiki/Rectilinear_polygon |
Top-down parsing in computer science is a parsing strategy where one first looks at the highest level of the parse tree and works down the parse tree by using the rewriting rules of a formal grammar. LL parsers are a type of parser that uses a top-down parsing strategy.
Top-down parsing is a strategy of analyzing unkno... | https://en.wikipedia.org/wiki/Top-down_parsing |
Earnshaw's theorem states that a collection of point charges cannot be maintained in a stable stationary equilibrium configuration solely by the electrostatic interaction of the charges. This was first proven by British mathematician Samuel Earnshaw in 1842.
It is usually cited in reference to magnetic fields, but was ... | https://en.wikipedia.org/wiki/Earnshaw%27s_theorem |
In computer science, a mark–compact algorithm is a type of garbage collection algorithm used to reclaim unreachable memory. Mark–compact algorithms can be regarded as a combination of the mark–sweep algorithm and Cheney's copying algorithm. First, reachable objects are marked, then a compacting step relocates the reach... | https://en.wikipedia.org/wiki/Mark%E2%80%93compact_algorithm |
Springer Science+Business Media, commonly known as Springer, is a German multinational publishing company of books, e-books and peer-reviewed journals in science, humanities, technical and medical (STM) publishing.
Originally founded in 1842 in Berlin, it expanded internationally in the 1960s, and through mergers in th... | https://en.wikipedia.org/wiki/Springer_Science%2BBusiness_Media |
In civil engineering and structural analysis Clapeyron's theorem of three moments (by Émile Clapeyron) is a relationship among the bending moments at three consecutive supports of a horizontal beam.
Let A,B,C-D be the three consecutive points of support, and denote by- l the length of AB and the length of BC, by w and... | https://en.wikipedia.org/wiki/Theorem_of_three_moments |
In q-analog theory, the -gamma function, or basic gamma function, is a generalization of the ordinary gamma function closely related to the double gamma function. It was introduced by . It is given by
$$
\Gamma_q(x) = (1-q)^{1-x}\prod_{n=0}^\infty \frac{1-q^{n+1}}{1-q^{n+x}}=(1-q)^{1-x}\,\frac{(q;q)_\infty}{(q^x;q)_\in... | https://en.wikipedia.org/wiki/Q-gamma_function |
Lamport's bakery algorithm is a computer algorithm devised by computer scientist Leslie Lamport, as part of his long study of the formal correctness of concurrent systems, which is intended to improve the safety in the usage of shared resources among multiple threads by means of mutual exclusion.
In computer science, i... | https://en.wikipedia.org/wiki/Lamport%27s_bakery_algorithm |
In physics, the wavefront of a time-varying wave field is the set (locus) of all points having the same phase. The term is generally meaningful only for fields that, at each point, vary sinusoidally in time with a single temporal frequency (otherwise the phase is not well defined).
Wavefronts usually move with time. ... | https://en.wikipedia.org/wiki/Wavefront |
The Pareto distribution, named after the Italian civil engineer, economist, and sociologist Vilfredo Pareto, is a power-law probability distribution that is used in description of social, quality control, scientific, geophysical, actuarial, and many other types of observable phenomena; the principle originally applied ... | https://en.wikipedia.org/wiki/Pareto_distribution |
In mathematics, a directed set (or a directed preorder or a filtered set) is a nonempty set
$$
A
$$
together with a reflexive and transitive binary relation
$$
\,\leq\,
$$
(that is, a preorder), with the additional property that every pair of elements has an upper bound. In other words, for any
$$
a
$$
and
$$
b
... | https://en.wikipedia.org/wiki/Directed_set |
In general topology, a branch of mathematics, the Appert topology, named for , is a topology on the set } of positive integers.
In the Appert topology, the open sets are those that do not contain 1, and those that asymptotically contain almost every positive integer. The space X with the Appert topology is called the ... | https://en.wikipedia.org/wiki/Appert_topology |
A funnel plot is a graph designed to check for the existence of publication bias; funnel plots are commonly used in systematic reviews and meta-analyses. In the absence of publication bias, it assumes that studies with high precision will be plotted near the average, and studies with low precision will be spread evenly... | https://en.wikipedia.org/wiki/Funnel_plot |
In algebra, a finitely generated group is a group G that has some finite generating set S so that every element of G can be written as the combination (under the group operation) of finitely many elements of S and of inverses of such elements.
By definition, every finite group is finitely generated, since S can be ta... | https://en.wikipedia.org/wiki/Finitely_generated_group |
In mathematics, a partial order or total order < on a set
$$
X
$$
is said to be dense if, for all
$$
x
$$
and
$$
y
$$
in
$$
X
$$
for which
$$
x < y
$$
, there is a
$$
z
$$
in
$$
X
$$
such that
$$
x < z < y
$$
. That is, for any two elements, one less than the other, there is another element between them. ... | https://en.wikipedia.org/wiki/Dense_order |
Tomasulo's algorithm is a computer architecture hardware algorithm for dynamic scheduling of instructions that allows out-of-order execution and enables more efficient use of multiple execution units. It was developed by Robert Tomasulo at IBM in 1967 and was first implemented in the IBM System/360 Model 91’s floating ... | https://en.wikipedia.org/wiki/Tomasulo%27s_algorithm |
In mathematics, a cubical complex (also called cubical set and Cartesian complex) is a set composed of points, line segments, squares, cubes, and their n-dimensional counterparts. They are used analogously to simplicial complexes and CW complexes in the computation of the homology of topological spaces. Non-positively ... | https://en.wikipedia.org/wiki/Cubical_complex |
The μ-law algorithm (sometimes written mu-law, often abbreviated as u-law) is a companding algorithm, primarily used in 8-bit PCM digital telecommunications systems in North America and Japan. It is one of the two companding algorithms in the G.711 standard from ITU-T, the other being the similar A-law. A-law is used i... | https://en.wikipedia.org/wiki/%CE%9C-law_algorithm |
Apriori is an algorithm for frequent item set mining and association rule learning over relational databases. It proceeds by identifying the frequent individual items in the database and extending them to larger and larger item sets as long as those item sets appear sufficiently often in the database. The frequent item... | https://en.wikipedia.org/wiki/Apriori_algorithm |
In computer science, an integer is a datum of integral data type, a data type that represents some range of mathematical integers. Integral data types may be of different sizes and may or may not be allowed to contain negative values. Integers are commonly represented in a computer as a group of binary digits (bits). T... | https://en.wikipedia.org/wiki/Integer_%28computer_science%29 |
A B+ tree is an m-ary tree with a variable but often large number of children per node. A B+ tree consists of a root, internal nodes and leaves. The root may be either a leaf or a node with two or more children.
A B+ tree can be viewed as a B-tree in which each node contains only keys (not key–value pairs), and to whic... | https://en.wikipedia.org/wiki/B%2B_tree |
Sankey diagrams are a data visualisation technique or flow diagram that emphasizes flow/movement/change from one state to another or one time to another, in which the width of the arrows is proportional to the flow rate of the depicted extensive property. The arrows being connected are called nodes and the connections ... | https://en.wikipedia.org/wiki/Sankey_diagram |
In mathematics, an involution, involutory function, or self-inverse function is a function that is its own inverse,
for all in the domain of . Equivalently, applying twice produces the original value.
## General properties
Any involution is a bijection.
The identity map is a trivial example of an involution. Example... | https://en.wikipedia.org/wiki/Involution_%28mathematics%29 |
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