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QEP Resources
QEP may refer to: * Quadrature encoder pulse, in a rotary encoder * Query plan or query execution plan, in a database software system * Quadratic eigenvalue problem In mathematics, the quadratic eigenvalue problemF. Tisseur and K. Meerbergen, The quadratic eigenvalue problem, SIAM Rev., 43 (2001), pp. 235–286. (QEP), is to find scalar eigenvalues \lambda, left eigenvectors y and right eigenvectors x such tha ..., a special case of nonlinear eigenproblem in mathematics * QEP Resources, a defunct American energy company. {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadrature Encoder
An incremental encoder is a linear or rotary electromechanical device that has two output signals, ''A'' and ''B'', which issue pulses when the device is moved. Together, the ''A'' and ''B'' signals indicate both the occurrence of and direction of movement. Many incremental encoders have an additional output signal, typically designated ''index'' or ''Z'', which indicates the encoder is located at a particular reference position. Also, some encoders provide a status output (typically designated ''alarm'') that indicates internal fault conditions such as a bearing failure or sensor malfunction. Unlike an absolute encoder, an incremental encoder does not indicate absolute position; it only reports changes in position and, for each reported position change, the direction of movement. Consequently, to determine absolute position at any particular moment, it is necessary to send the encoder signals to an '' incremental encoder interface'', which in turn will "track" and report the enc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Query Plan
In general, a query is a form of questioning, in a line of inquiry. Query may also refer to: Computing and technology * Query, a precise request for information retrieval made to a database or information system ** Query language, a computer language used to make queries into databases and information systems ** Query string, in the World Wide Web, is an optional part of a URL ** Web search query, a query entered by users into web search engines * Command-query separation (CQS), a concept in object-oriented programming, especially in the Eiffel programming language * jQuery, a lightweight JavaScript library that emphasizes interaction between JavaScript and HTML People with the name * Jeff Query (born 1967), an American football player * Nate Query, a musician Other uses * Query (complexity), a mapping from structures of one vocabulary to structures of another vocabulary * Query (Quaker), a question used for reflection and spiritual exercises among members of the Society of Fri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quadratic Eigenvalue Problem
In mathematics, the quadratic eigenvalue problemF. Tisseur and K. Meerbergen, The quadratic eigenvalue problem, SIAM Rev., 43 (2001), pp. 235–286. (QEP), is to find scalar eigenvalues \lambda, left eigenvectors y and right eigenvectors x such that : Q(\lambda)x = 0 ~ \text ~ y^\ast Q(\lambda) = 0, where Q(\lambda)=\lambda^2 A_2 + \lambda A_1 + A_0, with matrix coefficients A_2, \, A_1, A_0 \in \mathbb^ and we require that A_2\,\neq 0, (so that we have a nonzero leading coefficient). There are 2n eigenvalues that may be ''infinite'' or finite, and possibly zero. This is a special case of a nonlinear eigenproblem. Q(\lambda) is also known as a quadratic polynomial matrix. Applications A QEP can result in part of the dynamic analysis of structures discretized by the finite element method. In this case the quadratic, Q(\lambda) has the form Q(\lambda)=\lambda^2 M + \lambda C + K, where M is the mass matrix, C is the damping matrix and K is the stiffness matrix. Other applications ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
