useful gradient
121Expectation-maximization algorithm — An expectation maximization (EM) algorithm is used in statistics for finding maximum likelihood estimates of parameters in probabilistic models, where the model depends on unobserved latent variables. EM alternates between performing an… …
122Convex optimization — Convex minimization, a subfield of optimization, studies the problem of minimizing convex functions over convex sets. Given a real vector space X together with a convex, real valued function defined on a convex subset of X, the problem is to find …
123Non-negative matrix factorization — NMF redirects here. For the bridge convention, see new minor forcing. Non negative matrix factorization (NMF) is a group of algorithms in multivariate analysis and linear algebra where a matrix, , is factorized into (usually) two matrices, and… …
124Hagen-Poiseuille equation — The Hagen Poiseuille equation is a physical law that describes slow viscous incompressible flow through a constant circular cross section. It is also known as the Hagen Poiseuille law, Poiseuille law and Poiseuille equation.Equationtandard fluid… …
125United States — a republic in the N Western Hemisphere comprising 48 conterminous states, the District of Columbia, and Alaska in North America, and Hawaii in the N Pacific. 267,954,767; conterminous United States, 3,022,387 sq. mi. (7,827,982 sq. km); with… …
126canals and inland waterways — ▪ waterway Introduction natural or artificial waterways used for navigation, crop irrigation, water supply, or drainage. Despite modern technological advances in air and ground transportation, inland waterways continue to fill a vital …
127Defining equation (physics) — For common nomenclature of base quantities used in this article, see Physical quantity. For 4 vector modifications used in relativity, see Four vector. Very often defining equations are in the form of a constitutive equation, since parameters of… …
128Geographic information system — GIS redirects here. For other uses, see GIS (disambiguation). A geographic information system, geographical information science, or geospatial information studies is a system designed to capture, store, manipulate, analyze, manage, and present… …
