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Fault Diagnosis Method of Rolling Bearing Based on ESGMD-CC and AFSA-ELM
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作者 Jiajie He Fuzheng Liu +3 位作者 Xiangyi Geng Xifeng Liang Faye Zhang Mingshun Jiang 《Structural Durability & Health Monitoring》 EI 2024年第1期37-54,共18页
Incomplete fault signal characteristics and ease of noise contamination are issues with the current rolling bearing early fault diagnostic methods,making it challenging to ensure the fault diagnosis accuracy and relia... Incomplete fault signal characteristics and ease of noise contamination are issues with the current rolling bearing early fault diagnostic methods,making it challenging to ensure the fault diagnosis accuracy and reliability.A novel approach integrating enhanced Symplectic geometry mode decomposition with cosine difference limitation and calculus operator(ESGMD-CC)and artificial fish swarm algorithm(AFSA)optimized extreme learning machine(ELM)is proposed in this paper to enhance the extraction capability of fault features and thus improve the accuracy of fault diagnosis.Firstly,SGMD decomposes the raw vibration signal into multiple Symplectic geometry components(SGCs).Secondly,the iterations are reset by the cosine difference limitation to effectively separate the redundant components from the representative components.Additionally,the calculus operator is performed to strengthen weak fault features and make them easier to extract,and the singular value decomposition(SVD)weighted by power spectrum entropy(PSE)can be utilized as the sample feature representation.Finally,AFSA iteratively optimized ELM is adopted as the optimized classifier for fault identification.The superior performance of the proposed method has been validated by various experiments. 展开更多
关键词 Symplectic geometry mode decomposition calculus operator cosine difference limitation fault diagnosis AFSAELM model
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GENERALIZED FRACTIONAL CALCULUS OF THE ALEPH-FUNCTION INVOLVING A GENERAL CLASS OF POLYNOMIALS
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作者 R.K.SAXENA D.KUMAR 《Acta Mathematica Scientia》 SCIE CSCD 2015年第5期1095-1110,共16页
The object of this article is to study and develop the generalized fractional calcu- lus operators given by Saigo and Maeda in 1996. We establish generalized fractional calculus formulas involving the product of R-fun... The object of this article is to study and develop the generalized fractional calcu- lus operators given by Saigo and Maeda in 1996. We establish generalized fractional calculus formulas involving the product of R-function, Appell function F3 and a general class of poly- nomials. The results obtained provide unification and extension of the results given by Saxena et al. [13], Srivastava and Grag [17], Srivastava et al. [20], and etc. The results are obtained in compact form and are useful in preparing some tables of operators of fractional calculus. On account of the general nature of the Saigo-Maeda operators, R-function, and a general class of polynomials a large number of new and known results involving Saigo fractional calculus operators and several special functions notably H-function, /-function, Mittag-Leffier function, generalized Wright hypergeometric function, generalized Bessel-Maitland function follow as special cases of our main findings. 展开更多
关键词 generalized fractional calculus operators a general class of polynomials R-function H-FUNCTION /-function generalized Wright hypergeometric function Mittag-Leffler function generalized Bessel-Maitland function
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From Translation to Linear and Linear Canonical Transformations
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作者 Tan Si Do 《Applied Mathematics》 2022年第6期502-522,共21页
In order to obtain with simplicity the known and new properties of linear canonical transformations (LCTs), we show that any relation between a couple of operators (A,B) having commutator identical to unity, called du... In order to obtain with simplicity the known and new properties of linear canonical transformations (LCTs), we show that any relation between a couple of operators (A,B) having commutator identical to unity, called dual couple in this work, is valuable for any other dual couple, so that from the known translation operator exp(a&#8706;<sub>x</sub>) one may obtain the explicit form and properties of a category of linear and linear canonical transformations in 2N-phase spaces. Moreover, other forms of LCTs are also obtained in this work as so as the transforms by them of functions by integrations as so as by derivations. In this way, different kinds of LCTs such as Fast Fourier, Fourier, Laplace, Xin Ma and Rhodes, Baker-Campbell-Haussdorf, Bargman transforms are found again. 展开更多
关键词 Dual operators Fundamental Law of operator calculus Newtonian Binomial and Translation Linear and Linear Canonical Transforms From Fourier to Gauss and LCTs’ Transforms
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Lucas Symbolic Formulae and Generating Functions for Chebyshev Polynomials
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作者 Do Tan Si 《Journal of High Energy Physics, Gravitation and Cosmology》 2021年第3期914-924,共11页
This work shows that each kind of Chebyshev polynomials may be calculated from a symbolic formula similar to the Lucas formula for Bernoulli polynomials. It exposes also a new approach for obtaining generating functio... This work shows that each kind of Chebyshev polynomials may be calculated from a symbolic formula similar to the Lucas formula for Bernoulli polynomials. It exposes also a new approach for obtaining generating functions of them by operator calculus built from the derivative and the positional operators. 展开更多
关键词 Chebyshev Polynomials Lucas Symbolic Formula Generating Functions by operator calculus
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The Differential Transform
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作者 Eng. Mahmoud Abu Hilal 《Journal of Applied Mathematics and Physics》 2021年第8期1978-1992,共15页
One of the methods of mathematical analysis in many cases makes it possible to reduce the study of differential operators, pseudo-differential operators and certain types of integral operators and the solution of equa... One of the methods of mathematical analysis in many cases makes it possible to reduce the study of differential operators, pseudo-differential operators and certain types of integral operators and the solution of equations containing them, to an examination of simpler algebraic problems. The development and systematic use of operational calculus began with the work of O. Heaviside (1892), who proposed formal rules for dealing with the differentiation operator d/dt and solved a number of applied problems. However, he did not give operational calculus a mathematical basis;this was done with the aid of the Laplace transform;J. Mikusi<span style="white-space:nowrap;">&#324;</span>ski (1953) put operational calculus into algebraic form, using the concept of a function ring <a href="#ref1">[1]</a>. Thereupon I’m suggesting here the use of the integration operator dt to make an extension for the systematic use of operational calculus. Throughout designing and analyzing a control system, we need to treat the functionality of the system with respect to time. The reaction of the system instructs us how to stable it by amplifiers and feedbacks <a href="#ref2">[2]</a>, thereafter the Differential Transform is a good tool for doing this, and it’s a technique to frustrate difficulties we may bump into, also it has the methods to find the immediate reaction of the system with respect to infinitesimal (tiny) time which spares us from the hard work in finding the time dependent function, this could be done by producing finite series. 展开更多
关键词 Operational calculus Time Domain Differential Domain Serieses Difference to Differential Equation
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Discrete Fractional Birkhoff Equations in Terms of Time Scales
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作者 宋传静 张毅 《Journal of Donghua University(English Edition)》 EI CAS 2017年第3期430-435,共6页
In order to study discrete fractional Birkhoff equations for Birkhoffian systems,the method of isochronous variational principle is used in this paper. Discrete fractional Pfaff-Birkhoff principle in terms of time sca... In order to study discrete fractional Birkhoff equations for Birkhoffian systems,the method of isochronous variational principle is used in this paper. Discrete fractional Pfaff-Birkhoff principle in terms of time scales is presented. Discrete fractional Birkhoff equations with left and right discrete operators of Riemann-Liouville type are established and some special cases including classical discrete Birkhoff equations,discrete fractional Hamilton equations and discrete fractional Lagrange equations are discussed. Finally,an example is devoted to illustrate the results. 展开更多
关键词 Liouville fractional Riemann operators variational devoted calculus illustrate scales integer
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Operational Solution to the Nonlinear Klein-Gordon Equation
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作者 G.Bengochea L.Verde-Star M.Ortigueira 《Communications in Theoretical Physics》 SCIE CAS CSCD 2018年第5期506-512,共7页
We obtain solutions of the nonlinear Klein-Gordon equation using a novel operational method combined with the Adomian polynomial expansion of nonlinear functions. Our operational method does not use any integral trans... We obtain solutions of the nonlinear Klein-Gordon equation using a novel operational method combined with the Adomian polynomial expansion of nonlinear functions. Our operational method does not use any integral transforms nor integration processes. We illustrate the application of our method by solving several examples and present numerical results that show the accuracy of the truncated series approximations to the solutions. 展开更多
关键词 operational calculus partial differential equations nonlinear Klein-Gordon equation
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Improved algebraic method for linear continuous-time model identification
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作者 Wuhua Hu Jianfeng Mao 《Journal of Control and Decision》 EI 2014年第2期180-189,共10页
Recently a novel algebraic method was proposed for linear continuous-time model identification,which has attracted extensive attention in the literature.This work reveals its connection to classic identification metho... Recently a novel algebraic method was proposed for linear continuous-time model identification,which has attracted extensive attention in the literature.This work reveals its connection to classic identification methods,discusses a limitation and presents a useful modification of the method.The discussions are supported by analysis and numerical experiments. 展开更多
关键词 linear continuous-time model model identification operational calculus least squares instrumental variables derivative estimation
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