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94,900 | Then follows an explanation of chords with table of chords; observations of the obliquity of the ecliptic (the apparent path of the Sun through the stars); and an introduction to spherical trigonometry. Book II covers problems associated with the daily motion attributed to the heavens, namely risings and settings of ce... | Almagest | 0.77895 |
94,901 | The Almagest is a 2nd-century mathematical and astronomical treatise on the apparent motions of the stars and planetary paths, written by Claudius Ptolemy (c. AD 100 – c. 170) in Koine Greek. One of the most influential scientific texts in history, it canonized a geocentric model of the Universe that was accepted for m... | Almagest | 0.77895 |
94,902 | Ptolemy's comprehensive treatise of mathematical astronomy superseded most older texts of Greek astronomy. Some were more specialized and thus of less interest; others simply became outdated by the newer models. As a result, the older texts ceased to be copied and were gradually lost. Much of what we know about the wor... | Almagest | 0.77895 |
94,903 | Ptolemy wrote the Syntaxis as a textbook of mathematical astronomy. It explained geometrical models of the planets based on combinations of circles, which could be used to predict the motions of celestial objects. In a later book, the Planetary Hypotheses, Ptolemy explained how to transform his geometrical models into ... | Almagest | 0.77895 |
94,904 | He was unable to create accurate models for the remaining five planets. The Syntaxis adopted Hipparchus' solar model, which consisted of a simple eccentric deferent. For the Moon, Ptolemy began with Hipparchus' epicycle-on-deferent, then added a device that historians of astronomy refer to as a "crank mechanism": he su... | Almagest | 0.77895 |
94,905 | 190 BC) had introduced the deferent and epicycle and the eccentric deferent to astronomy. Hipparchus (2nd century BC) had crafted mathematical models of the motion of the Sun and Moon. Hipparchus had some knowledge of Mesopotamian astronomy, and he felt that Greek models should match those of the Babylonians in accurac... | Almagest | 0.77895 |
94,906 | In probability theory, a Poisson process is a stochastic process of which the simplest case involves "occurrences" at random times, the waiting time until the next occurrence having a memoryless exponential distribution, and the number of "occurrences" in any time interval having a Poisson distribution whose expected v... | Telescoping cancellation | 0.778949 |
94,907 | Richard Alexander Gibbs, , is an Australian geneticist. He is currently the Wofford Cain Chair and Professor of Molecular and Human Genetics at Baylor College of Medicine in Houston, Texas.In 1996, he founded the Human Genome Sequencing Center at BCM, which was one of five worldwide sites selected to complete the final... | Richard Gibbs (biologist) | 0.778947 |
94,908 | The goal (final cause) and formal cause are what something is for, its function: to a modern biologist, such teleology describes adaptation under the pressure of natural selection. The efficient cause is how a system develops and moves: to a modern biologist, those are explained by developmental biology and physiology.... | Aristotelian system | 0.778946 |
94,909 | Aristotle's biology is constructed on the basis of his theory of form, which is derived from Plato's theory of Forms, but significantly different from it. Plato's Forms were eternal and fixed, being "blueprints in the mind of God". Real things in the world could, in Plato's view, at best be approximations to these perf... | Aristotelian system | 0.778946 |
94,910 | In this sense, Aristotle's biology is scientific.From the data he collected and documented, Aristotle inferred quite a number of rules relating the life-history features of the live-bearing tetrapods (terrestrial placental mammals) that he studied. Among these correct predictions are the following. Brood size decreases... | Aristotelian system | 0.778946 |
94,911 | Aristotle did not do experiments in the modern sense. He used the ancient Greek term pepeiramenoi to mean observations, or at most investigative procedures, such as (in Generation of Animals) finding a fertilised hen's egg of a suitable stage and opening it so as to be able to see the embryo's heart inside.Instead, he ... | Aristotelian system | 0.778946 |
94,912 | After Theophrastus, though interest in Aristotle's ideas survived, they were generally taken unquestioningly. It is not until the age of Alexandria under the Ptolemies that advances in biology resumed. The first medical teacher at Alexandria, Herophilus of Chalcedon, corrected Aristotle, placing intelligence in the bra... | Aristotelian system | 0.778946 |
94,913 | Many classical works including those of Aristotle were transmitted from Greek to Syriac, then to Arabic, then to Latin in the Middle Ages. Aristotle remained the principal authority in biology for the next two thousand years. The Kitāb al-Hayawān (كتاب الحيوان, Book of Animals) is a 9th-century Arabic translation of Hi... | Aristotelian system | 0.778946 |
94,914 | In physics, the Polyakov action is an action of the two-dimensional conformal field theory describing the worldsheet of a string in string theory. It was introduced by Stanley Deser and Bruno Zumino and independently by L. Brink, P. Di Vecchia and P. S. Howe in 1976, and has become associated with Alexander Polyakov af... | Polyakov action | 0.778945 |
94,915 | After a brief time at University of California, Berkeley and 27 months in the French Navy, de Gennes became assistant professor at the University of Paris in Orsay. During his time at Orsay de Gennes worked on superconductors and liquid crystals.In 1991, Pierre-Gilles de Gennes was awarded the Nobel Prize for Physics f... | De Gennes Prize | 0.778945 |
94,916 | The De Gennes Prize (formerly known as the Prize for Materials Chemistry) was established in 2008 and is awarded biennially by the Royal Society of Chemistry for outstanding and exceptional work in the field of materials chemistry. The de Gennes Prize honours the work of Pierre-Gilles de Gennes.The recipient of the de ... | De Gennes Prize | 0.778945 |
94,917 | Source: Royal Society of Chemistry 2009 (2009): Matthew Rosseinsky, University of Liverpool. 2011 (2011): Steve Mann, University of Bristol. 2013 (2013): Susumu Kitagawa, Kyoto University. 2015 (2015): Mercouri Kanatzidis, Northwestern University 2017 (2017): Ian Manners, University of Bristol 2019 (2019): Eugenia Kuma... | De Gennes Prize | 0.778945 |
94,918 | In differential geometry and theoretical physics, the Petrov classification (also known as Petrov–Pirani–Penrose classification) describes the possible algebraic symmetries of the Weyl tensor at each event in a Lorentzian manifold. It is most often applied in studying exact solutions of Einstein's field equations, but ... | Petrov classification | 0.778945 |
94,919 | In some (more or less) familiar solutions, the Weyl tensor has the same Petrov type at each event: the Kerr vacuum is everywhere type D, certain Robinson/Trautman vacuums are everywhere type III, the pp-wave spacetimes are everywhere type N, the FLRW models are everywhere type O.More generally, any spherically symmetri... | Petrov classification | 0.778945 |
94,920 | Rosalind is a joint project between the University of California, San Diego and Saint Petersburg Academic University along with the Russian Academy of Sciences. The project's name commemorates Rosalind Franklin, whose X-ray crystallography with Raymond Gosling facilitated the discovery of the DNA double helix by James ... | Rosalind (education platform) | 0.778944 |
94,921 | Rosalind is an educational resource and web project for learning bioinformatics through problem solving and computer programming. Rosalind users learn bioinformatics concepts through a problem tree that builds up biological, algorithmic, and programming knowledge concurrently or learn by topics, with the topic of Align... | Rosalind (education platform) | 0.778944 |
94,922 | The federation has six permanent committees: Communications and publications: is in charge of demonstrating the application of physical sciences to medicine to the public. The committee is responsible for the dissemination of information on EFOMP activities to enhance the education, competence, research and continuing ... | European Federation of Organisations for Medical Physics | 0.77894 |
94,923 | EFOMP created an international network of relationships with other stakeholders in the field of physical science applied to healthcare. Collaborations: regional organisation member of the International Organization for Medical Physics (IOMP) collaborator with the International Atomic Energy Agency (IAEA) in the field o... | European Federation of Organisations for Medical Physics | 0.77894 |
94,924 | Several projects at European level with impact on medical physics matters and legislation have been undertaken. EFOMP is either in the advisory panel of multiple european projects or takes part in projects as a consortium member and endorses different projects that have an impact on and connection to medical physics pr... | European Federation of Organisations for Medical Physics | 0.77894 |
94,925 | The federation consists of national member organisations (NMOs) representing medical physics in Europe, where only one NMO can represent the corresponding nation The number of representatives each NMO can send into the council depends on the number of national members. The council is the governing authority of EFOMP an... | European Federation of Organisations for Medical Physics | 0.77894 |
94,926 | EFOMP is the umbrella organisation for 35 nations, each of which are constituted by one medical physics organisation and each representing together more than 9000 medical physicists and clinical engineers working in the field of medical physics. Each national society has a certain number of delegates in the council, de... | European Federation of Organisations for Medical Physics | 0.77894 |
94,927 | The European Federation of Organisations for Medical Physics (EFOMP) was founded in May 1980 in London to serve as an umbrella organisation representing the national Medical Physics societies in Europe. The office moved to Utrecht in January 2021. It is a non-profit organisation and aims to foster and coordinate the ac... | European Federation of Organisations for Medical Physics | 0.77894 |
94,928 | The EFOMP School for Medical Physics Experts (ESMPE) organizes medical physics education and training events specifically targeted to Medical Physicists who are already Medical Physics Experts (MPEs) or would like to achieve Medical Physics Expert status. Several editions were organised jointly with COCIR driven by the... | European Federation of Organisations for Medical Physics | 0.77894 |
94,929 | Every month a volume is published. According to the Institute for Scientific Information (ISI) the current Impact Factor is 2.532 (2018). There are three other scientific journals that EFOMP is associated with: Physiological Measurements owned by the Institute of Physics and Engineering in Medicine (IPEM) European Radi... | European Federation of Organisations for Medical Physics | 0.77894 |
94,930 | The owner of the journal is the Italian Association of Medical Physics (AIFM) and it is also the official organ of the French (SFPM), Irish (IAPM), Czech Republic (CAMP) and Hellenic (HAMP) Societies of Medical Physics. In 2019, EJMP has become official publication of the International Organization for Medical Physics ... | European Federation of Organisations for Medical Physics | 0.77894 |
94,931 | Included in the scope of the federation is to coordinate scientific activities and to support the development of guidelines and directives. A number of Working groups are operating for a specific time period to create quality control protocols, guidance documents, harmonise practices update core curricula.Every two yea... | European Federation of Organisations for Medical Physics | 0.77894 |
94,932 | Search analytics is the use of search data to investigate particular interactions among Web searchers, the search engine, or the content during searching episodes. The resulting analysis and aggregation of search engine statistics can be used in search engine marketing (SEM) and search engine optimization (SEO). In oth... | Search analytics | 0.77894 |
94,933 | Search analytics data can be collected in several ways. Search engines provide access to their own data with services such as Google Analytics, Google Trends and Google Insights. Third-party services must collect their data from ISP's, phoning home software, or from scraping search engines. Getting traffic statistics f... | Search analytics | 0.77894 |
94,934 | The technique was introduced in 1988 by Nadia Magnenat Thalmann, Richard Laperrière, and Daniel Thalmann. This technique is used in virtually all animation systems where simplified user interfaces allows animators to control often complex algorithms and a huge amount of geometry; most notably through inverse kinematics... | Skeletal animation | 0.778937 |
94,935 | Virtual anatomy properties such as weight of limbs, muscle reaction, bone strength, and joint constraints may be added for realistic bouncing, buckling, fracture, and tumbling effects known as virtual stunts. However, there are other applications of virtual anatomy simulations such as military and emergency response. V... | Skeletal animation | 0.778937 |
94,936 | Skeletal animation is the standard way to animate characters or mechanical objects for a prolonged period of time (usually over 100 frames). It is commonly used by video game artists and in the movie industry, and can also be applied to mechanical objects and any other object made up of rigid elements and joints. Perfo... | Skeletal animation | 0.778937 |
94,937 | Their size and shape are irregular too because they are not perfect spheres. Complicating moreover blood volume shape, red cells are not identically distributed in a blood sample volume because they migrate with velocity gradients in direction to the highest speed areas calling the famous representation of the Fåhræus–... | Hemorheology | 0.778935 |
94,938 | But in practice, blood properties vary with the geometry and blood has shown being an inadequate material to be studied as a fluid in common sense. So Maxwell Model gives trends that have to be completed in real situation followed by Thurston model in a vessel regarding distribution of cells in sheath and plug flows.If... | Hemorheology | 0.778935 |
94,939 | Mathematicians have studied the silver ratio since the time of the Greeks (although perhaps without giving a special name until recently) because of its connections to the square root of 2, its convergents, square triangular numbers, Pell numbers, octagons and the like. The relation described above can be expressed alg... | Silver triangle | 0.778935 |
94,940 | In numerical analysis and computational fluid dynamics, Godunov's scheme is a conservative numerical scheme, suggested by Sergei Godunov in 1959, for solving partial differential equations. One can think of this method as a conservative finite volume method which solves exact, or approximate Riemann problems at each in... | Godunov method | 0.778933 |
94,941 | The ligands can be chelates like EDTA, and can enable the electrolyte to be in neutral or alkaline conditions under which metal aquo complexes would otherwise precipitate. By blocking the coordination of water to the metal, organic ligands can inhibit metal-catalyzed water-splitting reactions, resulting in higher volta... | Redox flow battery | 0.778933 |
94,942 | The approach combines the basic structure of aqueous-flow batteries, which use electrode material suspended in a liquid electrolyte, with the chemistry of lithium-ion batteries in both carbon-free suspensions and slurries with conductive carbon network. The carbon free semi-solid redox flow battery is also sometimes re... | Redox flow battery | 0.778932 |
94,943 | A cryptographic n {\displaystyle n} -multilinear map is a kind of multilinear map, that is, a function e: G 1 × ⋯ × G n → G T {\displaystyle e:G_{1}\times \cdots \times G_{n}\rightarrow G_{T}} such that for any integers a 1 , … , a n {\displaystyle a_{1},\ldots ,a_{n}} and elements g i ∈ G i {\displaystyle g_{i}\in G_{... | Cryptographic multilinear map | 0.778932 |
94,944 | Birkhoff, G. D. (1931). "Proof of the ergodic theorem". | Equidistribution theorem | 0.778932 |
94,945 | While this theorem was proved in 1909 and 1910 separately by Hermann Weyl, Wacław Sierpiński and Piers Bohl, variants of this theorem continue to be studied to this day. In 1916, Weyl proved that the sequence a, 22a, 32a, ... mod 1 is uniformly distributed on the unit interval. In 1937, Ivan Vinogradov proved that the ... | Equidistribution theorem | 0.778932 |
94,946 | Joseph M. Rosenblatt and Máté Weirdl, Pointwise ergodic theorems via harmonic analysis, (1993) appearing in Ergodic Theory and its Connections with Harmonic Analysis, Proceedings of the 1993 Alexandria Conference, (1995) Karl E. Petersen and Ibrahim A. Salama, eds., Cambridge University Press, Cambridge, ISBN 0-521-459... | Equidistribution theorem | 0.778932 |
94,947 | In mathematics, the equidistribution theorem is the statement that the sequence a, 2a, 3a, ... mod 1is uniformly distributed on the circle R / Z {\displaystyle \mathbb {R} /\mathbb {Z} } , when a is an irrational number. It is a special case of the ergodic theorem where one takes the normalized angle measure μ = d θ 2 ... | Equidistribution theorem | 0.778932 |
94,948 | Now, for any N, because of the Euler–Lagrange theorem, on shell (and only on-shell), we have Q = ∫ N Q d n x + ∫ ∂ N ∂ L ∂ ( ∂ μ φ ) Q d s μ ≈ ∫ ∂ N f μ d s μ . {\displaystyle {\begin{aligned}Q\left&=\int _{N}\leftQ\,\mathrm {d} ^{n}x+\int _{\partial N}{\frac {\partial {\mathcal {L}}}{\partial (\partial _{\mu }\var... | Noether's first theorem | 0.778932 |
94,949 | To get to the usual version of Noether's theorem, we need additional restrictions on the action. We assume S {\displaystyle {\mathcal {S}}} is the integral over M of a function L ( φ , ∂ μ φ , x ) {\displaystyle {\mathcal {L}}(\varphi ,\partial _{\mu }\varphi ,x)} called the Lagrangian density, depending on φ {\displa... | Noether's first theorem | 0.778932 |
94,950 | Suppose we have an n-dimensional oriented Riemannian manifold, M and a target manifold T. Let C {\displaystyle {\mathcal {C}}} be the configuration space of smooth functions from M to T. (More generally, we can have smooth sections of a fiber bundle over M.) Examples of this M in physics include: In classical mechanics... | Noether's first theorem | 0.778932 |
94,951 | Noether's theorem is an on shell theorem: it relies on use of the equations of motion—the classical path. It reflects the relation between the boundary conditions and the variational principle. Assuming no boundary terms in the action, Noether's theorem implies that ∫ ∂ N J μ d s μ ≈ 0. {\displaystyle \int _{\partial N... | Noether's first theorem | 0.778932 |
94,952 | Practically all modern receivers are of the superheterodyne design. The RF signal from the antenna may have one stage of amplification to improve the receiver's noise figure, although at lower frequencies this is typically omitted. The RF signal enters a mixer, along with the output of the local oscillator, in order to... | Radio receiver design | 0.778932 |
94,953 | The formal proof of the theorem utilizes the condition of invariance to derive an expression for a current associated with a conserved physical quantity. In modern (since c. 1980) terminology, the conserved quantity is called the Noether charge, while the flow carrying that charge is called the Noether current. The Noe... | Noether's first theorem | 0.778932 |
94,954 | All fine technical points aside, Noether's theorem can be stated informally: If a system has a continuous symmetry property, then there are corresponding quantities whose values are conserved in time. A more sophisticated version of the theorem involving fields states that: To every differentiable symmetry generated by... | Noether's first theorem | 0.778932 |
94,955 | PEG, PEO, and POE refer to an oligomer or polymer of ethylene oxide. The three names are chemically synonymous, but historically PEG is preferred in the biomedical field, whereas PEO is more prevalent in the field of polymer chemistry. Because different applications require different polymer chain lengths, PEG has tend... | Poly(ethylene glycol) | 0.778931 |
94,956 | In statistics, the generalized canonical correlation analysis (gCCA), is a way of making sense of cross-correlation matrices between the sets of random variables when there are more than two sets. While a conventional CCA generalizes principal component analysis (PCA) to two sets of random variables, a gCCA generalizes... | Generalized canonical correlation | 0.778929 |
94,957 | In three-dimensional hyperbolic geometry, the alternated order-6 hexagonal tiling honeycomb is a uniform compact space-filling tessellation (or honeycomb). As an alternation, with Schläfli symbol h{4,3,6} and Coxeter-Dynkin diagram or , it can be considered a quasiregular honeycomb, alternating triangular tilings and t... | Runcitruncated order-6 cubic honeycomb | 0.778929 |
94,958 | The version of the Nanotechnology Research and Development Act that the House passed in May 2003 called for a study of the technical feasibility of molecular manufacturing, but this study was removed to safeguard funding of less controversial research before it was passed by the Senate and signed into law by President ... | There's Plenty of Room at the Bottom | 0.778927 |
94,959 | More concretely, his stature and concept of atomically precise fabrication played a role in securing funding for nanotechnology research, illustrated by President Clinton's January 2000 speech calling for a Federal program: My budget supports a major new National Nanotechnology Initiative, worth $500 million. Caltech i... | There's Plenty of Room at the Bottom | 0.778927 |
94,960 | These and other developments hint that the retroactive rediscovery of "Plenty of Room" gave nanotechnology a packaged history that provided an early date of December 1959, plus a connection to Richard Feynman.Toumey's analysis also includes comments from scientists in nanotechnology who say that "Plenty of Room" did no... | There's Plenty of Room at the Bottom | 0.778927 |
94,961 | Interest in "Plenty of Room" in the scientific literature greatly increased in the early 1990s. This is probably because the term "nanotechnology" gained serious attention just before that time, following its use by Drexler in his 1986 book, Engines of Creation: The Coming Era of Nanotechnology, which cited Feynman, an... | There's Plenty of Room at the Bottom | 0.778927 |
94,962 | K. Eric Drexler later took the Feynman concept of a billion tiny factories and added the idea that they could make more copies of themselves, via computer control instead of control by a human operator, in his 1986 book Engines of Creation: The Coming Era of Nanotechnology.After Feynman's death, scholars studying the h... | There's Plenty of Room at the Bottom | 0.778927 |
94,963 | "There's Plenty of Room at the Bottom: An Invitation to Enter a New Field of Physics" was a lecture given by physicist Richard Feynman at the annual American Physical Society meeting at Caltech on December 29, 1959. Feynman considered the possibility of direct manipulation of individual atoms as a more robust form of s... | There's Plenty of Room at the Bottom | 0.778927 |
94,964 | This engaged another gear with holes along the circumference, where pebbles (calculus) were located, that were to drop one by one into a box. The distance traveled would thus be given simply by counting the number of pebbles. Whether this instrument was ever built at the time is disputed. | Odometer | 0.778925 |
94,965 | Intersubband transitions (also known as intraband transitions) are dipolar allowed optical excitations between the quantized electronic energy levels within the conduction band of semiconductor heterostructures. Intersubband transitions when coupled with an optical resonator form new, mixed-state photons. This mixing i... | Intersubband transitions | 0.778925 |
94,966 | Symmetries are of prime importance in physics and are closely related to the hypothesis that certain physical quantities are only relative and unobservable. Symmetries apply to the equations that govern the physical laws (e.g. to a Hamiltonian or Lagrangian) rather than the initial conditions, values or magnitudes of t... | Time translational symmetry | 0.778923 |
94,967 | In mathematics, the Littlewood–Richardson rule is a combinatorial description of the coefficients that arise when decomposing a product of two Schur functions as a linear combination of other Schur functions. These coefficients are natural numbers, which the Littlewood–Richardson rule describes as counting certain skew... | Littlewood-Richardson coefficient | 0.778922 |
94,968 | Correspondence was central to science in the Victorian era. In his early years, most of the letters Darwin filed away were directly relevant to one of his ongoing scientific projects in geology, invertebrate zoology, and other fields. Most letters, however, were stuck onto "spits", as Darwin called them, and when his s... | Darwin Correspondence Project | 0.778921 |
94,969 | Life and Letters of Charles Darwin vol 1 at Project Gutenberg Life and Letters of Charles Darwin vol 2 at Project Gutenberg More Letters of Charles Darwin vol 1 at Project Gutenberg More Letters of Charles Darwin vol 2 at Project Gutenberg Letters on Geology The Complete Work of Charles Darwin Online Life and Letters a... | Darwin Correspondence Project | 0.778921 |
94,970 | The Kaufmann vortex, also known as the Scully model, is a mathematical model for a vortex taking account of viscosity. It uses an algebraic velocity profile. This vortex is not a solution of the Navier–Stokes equations.Kaufmann and Scully's model for the velocity in the Θ direction is: V Θ ( r ) = Γ 2 π r r c 2 + r 2 {... | Kaufmann vortex | 0.77892 |
94,971 | In physics, coherent backscattering is observed when coherent radiation (such as a laser beam) propagates through a medium which has a large number of scattering centers (such as milk or a thick cloud) of size comparable to the wavelength of the radiation. The waves are scattered many times while traveling through the ... | Coherent backscattering | 0.778919 |
94,972 | In mathematics, Eisenstein–Kronecker numbers are an analogue for imaginary quadratic fields of generalized Bernoulli numbers. They are defined in terms of classical Eisenstein–Kronecker series, which were studied by Kenichi Bannai and Shinichi Kobayashi using the Poincaré bundle.Eisenstein–Kronecker numbers are algebra... | Eisenstein–Kronecker number | 0.778919 |
94,973 | The theorem has a natural interpretation in the theory of finite Markov chains (where it is the matrix-theoretic equivalent of the convergence of an irreducible finite Markov chain to its stationary distribution, formulated in terms of the transition matrix of the chain; see, for example, the article on the subshift of... | Perron–Frobenius theorem | 0.778918 |
94,974 | For any non-negative matrix A its Perron–Frobenius eigenvalue r satisfies the inequality: r ≤ max i ∑ j a i j . {\displaystyle r\;\leq \;\max _{i}\sum _{j}a_{ij}.} This is not specific to non-negative matrices: for any matrix A with an eigenvalue λ {\displaystyle \scriptstyle \lambda } it is true that | λ | ≤ max i ∑ j... | Perron–Frobenius theorem | 0.778918 |
94,975 | All statements of the Perron–Frobenius theorem for positive matrices remain true for primitive matrices. The same statements also hold for a non-negative irreducible matrix, except that it may possess several eigenvalues whose absolute value is equal to its spectral radius, so the statements need to be correspondingly ... | Perron–Frobenius theorem | 0.778918 |
94,976 | In matrix theory, the Perron–Frobenius theorem, proved by Oskar Perron (1907) and Georg Frobenius (1912), asserts that a real square matrix with positive entries has a unique eigenvalue of largest magnitude and that eigenvalue is real. The corresponding eigenvector can be chosen to have strictly positive components, an... | Perron–Frobenius theorem | 0.778918 |
94,977 | In organometallic chemistry, a dicarbollide is an anion of the formula 2-. Various isomers exist, but most common is 1,2-dicarbollide derived from ortho-carborane. These dianions function as ligands, related to the cyclopentadienyl anion. Substituted dicarbollides are also known such as − (pyridine bonded to B) and 2- ... | Dicarbollide | 0.778918 |
94,978 | More generally, it can be extended to the case of non-negative compact operators, which, in many ways, resemble finite-dimensional matrices. These are commonly studied in physics, under the name of transfer operators, or sometimes Ruelle–Perron–Frobenius operators (after David Ruelle). In this case, the leading eigenva... | Perron–Frobenius theorem | 0.778918 |
94,979 | The Perron–Frobenius theorem describes the properties of the leading eigenvalue and of the corresponding eigenvectors when A is a non-negative real square matrix. Early results were due to Oskar Perron (1907) and concerned positive matrices. Later, Georg Frobenius (1912) found their extension to certain classes of non-... | Perron–Frobenius theorem | 0.778918 |
94,980 | Since 2005, production of solar cells in China has expanded 100-fold. As Chinese renewable manufacturing has grown, the costs of renewable energy technologies have dropped. Innovation has helped, but the main driver of reduced costs has been market expansion.See also renewable energy in the United States for US-figures... | Renewable energy policy | 0.778917 |
94,981 | In 2013, China led the world in renewable energy production, with a total capacity of 378 GW, mainly from hydroelectric and wind power. As of 2014, China leads the world in the production and use of wind power, solar photovoltaic power and smart grid technologies, generating almost as much water, wind and solar energy ... | Renewable energy policy | 0.778917 |
94,982 | Based on REN21's 2014 report, renewables contributed 19 percent to our energy consumption and 22 percent to our electricity generation in 2012 and 2013, respectively. This energy consumption is divided as 9% coming from traditional biomass, 4.2% as heat energy (non-biomass), 3.8% hydro electricity and 2% electricity fr... | Renewable energy policy | 0.778917 |
94,983 | In 2008 for the first time, more renewable energy than conventional power capacity was added in both the European Union and United States, demonstrating a "fundamental transition" of the world's energy markets towards renewables, according to a report released by REN21, a global renewable energy policy network based in... | Renewable energy policy | 0.778917 |
94,984 | Global ethanol production for transport fuel tripled between 2000 and 2007 from 17 billion to more than 52 billion litres, while biodiesel expanded more than tenfold from less than 1 billion to almost 11 billion litres. Biofuels provide 1.8% of the world's transport fuel and recent estimates indicate a continued high g... | Renewable energy policy | 0.778917 |
94,985 | The IEA has identified three actions which will allow renewable energy and other clean energy technologies to "more effectively compete for private sector capital". "First, energy prices must appropriately reflect the "true cost" of energy (e.g. through carbon pricing) so that the positive and negative impacts of energ... | Renewable energy policy | 0.778917 |
94,986 | However, in some cases poor investment designs have caused bankruptcies and low returns, and unrealistic promises have been shown to be far from reality. Nuclear power plants were closed, and the existing nine plants will close earlier than planned, in 2022. One factor that has inhibited efficient employment of new ren... | Renewable energy policy | 0.778917 |
94,987 | The phase-out of Germany's fleet of nuclear reactors, to be complete by 2022, is a key part of the program.Legislative support for the Energiewende was passed in late 2010 and includes greenhouse gas (GHG) reductions of 80–95% by 2050 (relative to 1990) and a renewable energy target of 60% by 2050. These targets are am... | Renewable energy policy | 0.778917 |
94,988 | The Energiewende (German for energy transition) is the transition by Germany to a low carbon, environmentally sound, reliable, and affordable energy supply. The new system will rely heavily on renewable energy (particularly wind, photovoltaics, and biomass) energy efficiency, and energy demand management. Most if not a... | Renewable energy policy | 0.778917 |
94,989 | The International Solar Energy Society has stated that "historical incentives for the conventional energy resources continue even today to bias markets by burying many of the real societal costs of their use".Fossil-fuel energy systems have different production, transmission, and end-use costs and characteristics than ... | Renewable energy policy | 0.778917 |
94,990 | Public policy has a role to play in renewable energy commercialization because the free market system has some fundamental limitations. As the Stern Review points out: "In a liberalised energy market, investors, operators and consumers should face the full cost of their decisions. But this is not the case in many econo... | Renewable energy policy | 0.778917 |
94,991 | Poor public perception of renewable energy system aesthetics. Lack of stakeholder/community participation and co-operation in energy choices and renewable energy projects.With such a wide range of non-technical barriers, there is no "silver bullet" solution to drive the transition to renewable energy. So ideally there ... | Renewable energy policy | 0.778917 |
94,992 | Imperfect capital markets, which includes failure to internalize all costs of conventional energy (e.g., effects of air pollution, risk of supply disruption) and failure to internalize all benefits of renewable energy (e.g., cleaner air, energy security). Inadequate workforce skills and training, which includes lack of... | Renewable energy policy | 0.778917 |
94,993 | Lack of information dissemination and consumer awareness. Higher capital cost of renewable energy technologies compared with conventional energy technologies. Inadequate financing options for renewable energy projects, including insufficient access to affordable financing for project developers, entrepreneurs and consu... | Renewable energy policy | 0.778917 |
94,994 | Large-scale renewables may also encounter problems if they are sited in areas far from existing grids." Lack of government policy support, which includes the lack of policies and regulations supporting deployment of renewable energy technologies and the presence of policies and regulations hindering renewable energy de... | Renewable energy policy | 0.778917 |
94,995 | Benjamin K. Sovacool has argued that "some of the most surreptitious, yet powerful, impediments facing renewable energy and energy efficiency in the United States are more about culture and institutions than engineering and science".The obstacles to the widespread commercialization of renewable energy technologies are ... | Renewable energy policy | 0.778917 |
94,996 | Developing countries with renewable energy targets include China, India, Indonesia, Malaysia, the Philippines, Thailand, Brazil, Egypt, Mali, and South Africa. The targets set by many developing countries are quite modest when compared with those in some industrialized countries.Renewable energy targets in most countri... | Renewable energy policy | 0.778917 |
94,997 | Setting national renewable energy targets can be an important part of a renewable energy policy and these targets are usually defined as a percentage of the primary energy and/or electricity generation mix. For example, the European Union has prescribed an indicative renewable energy target of 12 percent of the total E... | Renewable energy policy | 0.778917 |
94,998 | The disproportiation of niobium(IV) chloride can be used to make tetrachlorobis(tetrahydrofuran) niobium, a useful synthon in NbIV chemistry due to the lability of the attached tetrahydrofuran ligands. This compound can be synthesized by first reacting NbCl5 with aluminium in acetonitrile followed by addition of tetrah... | Niobium tetrachloride | 0.778917 |
94,999 | Maya astronomy was naked-eye astronomy based on the observations of the azimuths of the rising and setting of heavenly bodies. City planning and alignment was often arranged in line with astronomical paths and events. The Maya also believed that the will and actions of gods could be interpreted in the alignment of the ... | Mayan astronomy | 0.778916 |
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