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THE ASYMPTOTIC BEHAVIOR AND OSCILLATION FOR A CLASS OF THIRD-ORDER NONLINEAR DELAY DYNAMIC EQUATIONS
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作者 黄先勇 邓勋环 王其如 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期925-946,共22页
In this paper,we consider a class of third-order nonlinear delay dynamic equations.First,we establish a Kiguradze-type lemma and some useful estimates.Second,we give a sufficient and necessary condition for the existe... In this paper,we consider a class of third-order nonlinear delay dynamic equations.First,we establish a Kiguradze-type lemma and some useful estimates.Second,we give a sufficient and necessary condition for the existence of eventually positive solutions having upper bounds and tending to zero.Third,we obtain new oscillation criteria by employing the Potzsche chain rule.Then,using the generalized Riccati transformation technique and averaging method,we establish the Philos-type oscillation criteria.Surprisingly,the integral value of the Philos-type oscillation criteria,which guarantees that all unbounded solutions oscillate,is greater than θ_(4)(t_(1),T).The results of Theorem 3.5 and Remark 3.6 are novel.Finally,we offer four examples to illustrate our results. 展开更多
关键词 nonlinear delay dynamic equations NONOSCILLATION asymptotic behavior Philostype oscillation criteria generalized Riccati transformation
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Weak Fault Feature Extraction of the Rotating Machinery Using Flexible Analytic Wavelet Transform and Nonlinear Quantum Permutation Entropy
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作者 Lili Bai Wenhui Li +3 位作者 He Ren Feng Li TaoYan Lirong Chen 《Computers, Materials & Continua》 SCIE EI 2024年第6期4513-4531,共19页
Addressing the challenges posed by the nonlinear and non-stationary vibrations in rotating machinery,where weak fault characteristic signals hinder accurate fault state representation,we propose a novel feature extrac... Addressing the challenges posed by the nonlinear and non-stationary vibrations in rotating machinery,where weak fault characteristic signals hinder accurate fault state representation,we propose a novel feature extraction method that combines the Flexible Analytic Wavelet Transform(FAWT)with Nonlinear Quantum Permutation Entropy.FAWT,leveraging fractional orders and arbitrary scaling and translation factors,exhibits superior translational invariance and adjustable fundamental oscillatory characteristics.This flexibility enables FAWT to provide well-suited wavelet shapes,effectively matching subtle fault components and avoiding performance degradation associated with fixed frequency partitioning and low-oscillation bases in detecting weak faults.In our approach,gearbox vibration signals undergo FAWT to obtain sub-bands.Quantum theory is then introduced into permutation entropy to propose Nonlinear Quantum Permutation Entropy,a feature that more accurately characterizes the operational state of vibration simulation signals.The nonlinear quantum permutation entropy extracted from sub-bands is utilized to characterize the operating state of rotating machinery.A comprehensive analysis of vibration signals from rolling bearings and gearboxes validates the feasibility of the proposed method.Comparative assessments with parameters derived from traditional permutation entropy,sample entropy,wavelet transform(WT),and empirical mode decomposition(EMD)underscore the superior effectiveness of this approach in fault detection and classification for rotating machinery. 展开更多
关键词 Rotating machinery quantum theory nonlinear quantum permutation entropy Flexible Analytic Wavelet Transform(FAWT) feature extraction
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NONLINEAR TIME TRANSFORMATION METHOD FOR STRONG NONLINEAR OSCILLATION SYSTEMS 被引量:5
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作者 徐兆 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1992年第3期279-288,共10页
In this paper,a nonlinear time transformation method is presented for the analysis of strong nonlinear oscillation systems.This method can be used to study the limit cycle behavior of the autonomous systems and to ana... In this paper,a nonlinear time transformation method is presented for the analysis of strong nonlinear oscillation systems.This method can be used to study the limit cycle behavior of the autonomous systems and to analyze the forced vibration of a strong nonlinear system. 展开更多
关键词 strong nonlinear oscillation nonlinear time transformation method
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SYMMETRIES, BāCKLUND TRANSFORMATIONS AND BOUNDARY-INITIAL VALUE PROBLEMS FOR NONLINEAR CHROMATOGRAPHY EQUATION 被引量:1
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作者 王明亮 《Acta Mathematica Scientia》 SCIE CSCD 1995年第2期152-160,共9页
In the present paper, an equation of nonlinear chromatography is derived from the physical chemistry A recursion formula of the symmetries of the equation as well as an infinite number of symmetries is found. A series... In the present paper, an equation of nonlinear chromatography is derived from the physical chemistry A recursion formula of the symmetries of the equation as well as an infinite number of symmetries is found. A series of Backlund transformations of the equation are constructed by means of the symmetries. The exact solutions of two boundary-initial value problems on the half straight line for the equation are given m terms of the solutions of the corresponding linear problems. 展开更多
关键词 SYMMETRIES Backlund transformations nonlinear boundary-initial value problems exact solutions equation of nonlinear chromatography
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N-Fold Darboux Transformation for the Nonlocal Nonlinear Schrodinger(NNLS)Equation with the Self-Induced PT-Symmetric Potential 被引量:2
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作者 Chaonan Duan Fajun Yu 《Journal of Applied Mathematics and Physics》 2018年第4期888-900,共13页
The Darboux transformation (DT) method is studied in a lot of local equations, but there are few of work to solve nonlocal equations by DT. In this letter, we solve the nonlocal nonlinear Schr&#246;dinger equation... The Darboux transformation (DT) method is studied in a lot of local equations, but there are few of work to solve nonlocal equations by DT. In this letter, we solve the nonlocal nonlinear Schr&#246;dinger equation (NNLSE) with the self-induced PT-symmetric potential by DT. Then the N-fold DT of NNLSE is derived with the help of the gauge transformation between the Lax pairs. Then we derive some novel exact solutions including the bright soliton, breather wave soliton. In particularly, the dynamic features of one-soliton, two-soliton, three-soliton solutions and the elastic interactions between the two solitons are displayed. 展开更多
关键词 Nonlocal nonlinear Schrodinger Equation N-Fold Darboux transformation Lax Pairs Exact Solution
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N-Fold Darboux Transformation for a Nonlinear Evolution Equation 被引量:2
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作者 Yannan Zhao 《Applied Mathematics》 2012年第8期943-948,共6页
In this paper, we present a N-fold Darboux transformation (DT) for a nonlinear evolution equation. Comparing with other types of DTs, we give the relationship between new solutions and the trivial solution. The DT pre... In this paper, we present a N-fold Darboux transformation (DT) for a nonlinear evolution equation. Comparing with other types of DTs, we give the relationship between new solutions and the trivial solution. The DT presented in this paper is more direct and universal to obtain explicit solutions. 展开更多
关键词 Darboux transformation Derivative nonlinear Schrodinger Equation Explicit Solution
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Generalized Darboux Transformation and Rational Solutions for the Nonlocal Nonlinear Schrodinger Equation with the Self-Induced Parity-Time Symmetric Potential 被引量:1
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作者 Jian Chen 《Journal of Applied Mathematics and Physics》 2015年第5期530-536,共7页
In this paper, I construct a generalized Darboux transformation for the nonlocal nonlinear Schrodinger equation with the self-induced parity-time symmetric potential. The N-order rational solution is derived by the it... In this paper, I construct a generalized Darboux transformation for the nonlocal nonlinear Schrodinger equation with the self-induced parity-time symmetric potential. The N-order rational solution is derived by the iterative rule and it can be expressed by the determinant form. In particular, I calculate first-order and second-order rational solutions and obtain their figures according to different parameters. 展开更多
关键词 Generalized Darboux transformation Rational Solutions Nonlocal nonlinear Schrodinger Equation
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Darboux Transformation and Soliton Solutions for Inhomogeneous Coupled Nonlinear Schr(o|¨)dinger Equations with Symbolic Computation
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作者 XUE Yu-Shan TIAN Bo +4 位作者 ZHANG Hai-Qiang LIU Wen-Jun LI Li-Li QI Feng-Hua ZHAN Yan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第11期888-896,共9页
With the aid of computation, we consider the variable-coefficient coupled nonlinear Schrodinger equations with the effects of group-velocity dispersion, self-phase modulation and cross-phase modulation, which have pot... With the aid of computation, we consider the variable-coefficient coupled nonlinear Schrodinger equations with the effects of group-velocity dispersion, self-phase modulation and cross-phase modulation, which have potential applications in the long-distance communication of two-pulse propagation in inhomogeneous optical fibers. Based on the obtained nonisospectral linear eigenvalue problems (i.e. Lax pair), we construct the Darboux transformation for such a model to derive the optical soliton solutions. In addition, through the one- and two-soliton-like solutions, we graphically discuss the features of picosecond solitons in inhomogeneous optical fibers. 展开更多
关键词 variable-coefficient coupled nonlinear Schrodinger equations optical solitons Darboux transformation symbolic computation
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A Bilinear Bcklund Transformation and N-Soliton-Like Solution of Three Coupled Higher-Order Nonlinear Schrdinger Equations with Symbolic Computation
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作者 ZHU Hong-Wu TIAN Bo +2 位作者 MENG Xiang-Hua LI Juan XU Tao 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第9期689-695,共7页
A bilinear Baecklund transformation is presented for the three coupled higher-order nonlinear Schroedinger equations with the inclusion of the group velocity dispersion, third-order dispersion and Kerr-law nonlinearit... A bilinear Baecklund transformation is presented for the three coupled higher-order nonlinear Schroedinger equations with the inclusion of the group velocity dispersion, third-order dispersion and Kerr-law nonlinearity, which can describe the dynamics of alpha helical proteins in living systems as well as the propagation of ultrashort pulses in wavelength-division multiplexed system. Starting from the Baecklund transformation, the analytical soliton solution is obtained from a trivial solution. Simultaneously, the N-soliton-like solution in double Wronskian form is constructed, and the corresponding proof is also given via the Wronskian technique. The results obtained from this paper might be valuable in studying the transfer of energy in biophysics and the transmission of light pulses in optical communication systems. 展开更多
关键词 coupled higher-order nonlinear Schroedinger equations Baecklund transformation soliton solution Wronskian technique symbolic computation
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Soliton Solutions and Bilinear Bcklund Transformation for Generalized Nonlinear Schrdinger Equation with Radial Symmetry
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作者 江彦 田播 +2 位作者 刘文军 孙鲲 屈启兴 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第10期635-640,共6页
Investigated in this paper is the generalized nonlinear Schrodinger equation with radial symmetry. With the help of symbolic computation, the one-, two-, and N-soliton solutions are obtained through the bilinear metho... Investigated in this paper is the generalized nonlinear Schrodinger equation with radial symmetry. With the help of symbolic computation, the one-, two-, and N-soliton solutions are obtained through the bilinear method. B^cklund transformation in the bilinear form is presented, through which a new solution is constructed. Graphically, we have found that the solitons are symmetric about x = O, while the soliton pulse width and amplitude will change along with the distance and time during the propagation. 展开更多
关键词 generalized nonlinear SchrSdinger equation radial symmetry bilinear method symbolic computation soliton solutions Bgcklund transformation
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About Nonlinear Mechanism of Energy Transformation at Ion Implantation
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作者 S.G.Psakhie, K.P.Zolnikov, R.I.Kadyrov, G.E.Rudenskii, S.A.Vassiliev and Yu.P.Shatheev (Institute of Strength Physics and Materials Science, Russian Academy of Sciences, Siberian Branch, Tomsk, Russia) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1999年第6期581-582,共2页
The peculiarities of energy dissipation transferred by solitary waves on defects such as freesurface, grain boundary, region with high concentration of vacancies are studied. One of theways of description of the long ... The peculiarities of energy dissipation transferred by solitary waves on defects such as freesurface, grain boundary, region with high concentration of vacancies are studied. One of theways of description of the long range effect taking place at ion implantation in metallic materialsis suggested. 展开更多
关键词 About nonlinear Mechanism of Energy transformation at Ion Implantation
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Research on the Automation Control Information System Model based on the Chaos and Nonlinear Transformation
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作者 Leping Wang Yongyong Xiong 《International Journal of Technology Management》 2016年第8期69-71,共3页
In this paper, we conduct research on the automation control information system model based on the Chaos and nonlineartransformation. Electronic control automation system in the process of social and economic developm... In this paper, we conduct research on the automation control information system model based on the Chaos and nonlineartransformation. Electronic control automation system in the process of social and economic development plays the key role is obvious, it caneffectively encourage industry automation level is improved greatly, at the same time, electronic automation system control to the larger extenton saving the cost of enterprise. Electronic systems control automation industrial enterprises should also improve their in technical innovationability, to have independent intellectual property rights of electronic automation engineering control system. This paper combines the Chaos andnonlinear transformation principles to optimize the traditional system that is meaningful. 展开更多
关键词 Automation Control Information System Chaos and nonlinear transformation.
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Breather and its interaction with rogue wave of the coupled modified nonlinear Schrodinger equation
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作者 王明 徐涛 +1 位作者 何国亮 田雨 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第5期350-356,共7页
We investigate the coupled modified nonlinear Schr?dinger equation.Breather solutions are constructed through the traditional Darboux transformation with nonzero plane-wave solutions.To obtain the higher-order localiz... We investigate the coupled modified nonlinear Schr?dinger equation.Breather solutions are constructed through the traditional Darboux transformation with nonzero plane-wave solutions.To obtain the higher-order localized wave solution,the N-fold generalized Darboux transformation is given.Under the condition that the characteristic equation admits a double-root,we present the expression of the first-order interactional solution.Then we graphically analyze the dynamics of the breather and rogue wave.Due to the simultaneous existence of nonlinear and self-steepening terms in the equation,different profiles in two components for the breathers are presented. 展开更多
关键词 coupled modified nonlinear Schr?dinger equation Darboux transformation BREATHER rouge wave
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A NONLINEAR TRANSFORMATION AND A BOUNDARY-INITIAL VALUE PROBLEM FOR A CLASS OF NONLINEAR CONVECTION-DIFFUSION EQUATIONS 被引量:2
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作者 王明亮 江寿桂 白雪 《Acta Mathematica Scientia》 SCIE CSCD 2001年第1期114-120,共7页
With the aid of a nonlinear transformation, a class of nonlinear convection-diffusion PDE in one space dimension is converted into a linear one, the unique solution of a nonlinear boundary-initial value problem for th... With the aid of a nonlinear transformation, a class of nonlinear convection-diffusion PDE in one space dimension is converted into a linear one, the unique solution of a nonlinear boundary-initial value problem for the nonlinear PDE can be exactly expressed by the nonlinear transformation, and several illustrative examples are given. 展开更多
关键词 nonlinear transformation convection-diffusion PDE boundary-initial value problem exact explicit solutions
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Application of Unscented Transformation for Nonlinear State Smoothing 被引量:6
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作者 WANG Xiao-Xu PAN Quan +1 位作者 LIANG Yan ZHAO Chun-Hui 《自动化学报》 EI CSCD 北大核心 2012年第7期1107-1112,共6页
关键词 非线性状态 最优平滑 UT变换 应用 最小均方误差 KALMAN 离散系统 状态估计
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A Bäcklund Transformation of a Kind of Nonlinear Wave Equation
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作者 HAI Wenhua 《Chinese Physics Letters》 SCIE CAS CSCD 1993年第7期389-392,共4页
Applying the method of canonical,transformation,we studied the nonlinear wave equationφ_(xx)-φ_(tt)=dF(φ)/dφ.A Bäcklund transformation(BT)of this equation is obtained.Combining BT of this equation with the we... Applying the method of canonical,transformation,we studied the nonlinear wave equationφ_(xx)-φ_(tt)=dF(φ)/dφ.A Bäcklund transformation(BT)of this equation is obtained.Combining BT of this equation with the well-known BT of sine-Gordon equation(SGE),a formula of nonlinear superposition which contains some arbitrary functions of x and t has been established.This formula leads to a kind of general solution of SGE through its some known solutions.The general soliton solutions and their properties are simply discussed. 展开更多
关键词 EQUATION nonlinear transformation
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Transformation of Nonlinear Surface Gravity Waves under Shallow-Water Conditions
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作者 Iftikhar B. Abbasov 《Applied Mathematics》 2010年第4期260-264,共5页
This article describes transformation of nonlinear surface gravity waves under shallow-water conditions with the aid of the suggested semigraphical method. There are given profiles of surface gravity waves on the cres... This article describes transformation of nonlinear surface gravity waves under shallow-water conditions with the aid of the suggested semigraphical method. There are given profiles of surface gravity waves on the crests steepening stages, their leading edges steepening. There are discussed the spectral component influence on the transformation of surface wave profile. 展开更多
关键词 nonlinear SURFACE GRAVITY WAVES SHALLOW-WATER Semigraphical Method transformation of SURFACE Wave Profile
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Numerical Simulation of Nonlinear Surface Gravity Waves Transformation under Shallow-Water Conditions
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作者 Iftikhar B. Abbasov 《Applied Mathematics》 2012年第2期135-141,共7页
This work considers the problems of numerical simulation of non-linear surface gravity waves transformation under shallow bay conditions. The discrete model is built from non-linear shallow-water equations. Are result... This work considers the problems of numerical simulation of non-linear surface gravity waves transformation under shallow bay conditions. The discrete model is built from non-linear shallow-water equations. Are resulted boundary and initial conditions. The method of splitting into physical processes receives system from three equations. Then we define the approximation order and investigate stability conditions of the discrete model. The sweep method was used to calculate the system of equations. This work presents surface gravity wave profiles for different propagation phases. 展开更多
关键词 Equations of SHALLOW-WATER Numerical Modelling nonlinear SURFACE GRAVITY WAVES transformation of SURFACE Wave Profile
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Extended Mapping Transformation Method and Its Applications to Nonlinear Partial Differential Equation(s)
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作者 ZHAO Hong BAI Cheng-Lin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第3X期473-478,共6页
In this paper, we extend the mapping transformation method through introducing variable coefficients.By means of the extended mapping transformation method, many explicit and exact general solutions with arbitrary fun... In this paper, we extend the mapping transformation method through introducing variable coefficients.By means of the extended mapping transformation method, many explicit and exact general solutions with arbitrary functions for some nonlinear partial differential equations, which contain solitary wave solutions, trigonometric function solutions, and rational solutions, are obtained. 展开更多
关键词 nonlinear partial differential equations extended mapping transformation method exact solutions
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A NEW APPROACH TO BACKLUND TRANSFORMATIONSOF NONLINEAR EVOLUTION EQUATIONS
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作者 范恩贵 张鸿庆 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第7期645-650,共6页
In this paper, a new approach to Backlund transformations of nonlinear evolution equations is presented. The results obtained by this procedure are completely the same as that by Painleve truncating expansion.
关键词 nonlinear evolution equation Backlund transformation Lax pair
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