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SOME OSCILLATION CRITERIA FOR SECOND ORDER NONLINEAR FUNCTIONAL ORDINARY DIFFERENTIAL EQUATIONS
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作者 E.M.E.Zayed M.A.El-Moneam 《Acta Mathematica Scientia》 SCIE CSCD 2007年第3期602-610,共9页
The main objective of this article is to study the oscillatory behavior of the solutions of the following nonlinear functional differential equations(a(t)x'(t))'+δ1p(t)x'(t) +δ2q(t)f(x(g(t))) ... The main objective of this article is to study the oscillatory behavior of the solutions of the following nonlinear functional differential equations(a(t)x'(t))'+δ1p(t)x'(t) +δ2q(t)f(x(g(t))) = 0,for 0 ≤ to≤ t, where 51 = :El and δ±1. The functions p,q,g : [t0, ∞) → R, f : R → are continuous, a(t) 〉 0,p(t) ≥0,q(t) 〉 0 for t ≥ to,lirn g(t) = ∞, and q is not identically zero on any subinterval of [to, ∞). Moreover, the functions q(t), g(t), and a(t) are continuously differentiable. 展开更多
关键词 Oscillatory and nonoscillatory solutions nonlinear functional differential equations
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A large-range convergence iterative method for solving a nonlinear functional equation
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作者 母丽华 沈继红 杜红 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第5期631-634,共4页
The existence and representation of the exact solution are given for a nonlinear functional equation in the reproducing kernel space. For a numerical computation, we present a large-range convergence iterative method ... The existence and representation of the exact solution are given for a nonlinear functional equation in the reproducing kernel space. For a numerical computation, we present a large-range convergence iterative method for solving the nonlinear functional equation. In the iterative method, the convergent condition is simple and the convergence is irrespective to the choice of the initial function. It is worthy to note that the presented method can be generalized to solve other nonlinear operator equations. 展开更多
关键词 非线性泛函方程 非线性积分方程 再生核 计算机理论
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Existence Theorem for a Nonlinear Functional Integral Equation and an Initial Value Problem of Fractional Order in L<sub>1</sub>(R<sub>+</sub>)
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作者 Ibrahim Abouelfarag Ibrahim Tarek S. Amer Yasser M. Aboessa 《Applied Mathematics》 2013年第2期402-409,共8页
The aim of this paper is to study the existence of integrable solutions of a nonlinear functional integral equation in the space of Lebesgue integrable functions on unbounded interval, L1(R+). As an application we ded... The aim of this paper is to study the existence of integrable solutions of a nonlinear functional integral equation in the space of Lebesgue integrable functions on unbounded interval, L1(R+). As an application we deduce the existence of solution of an initial value problem of fractional order that be studied only on a bounded interval. The main tools used are Schauder fixed point theorem, measure of weak noncompactness, superposition operator and fractional calculus. 展开更多
关键词 nonlinear functional Integral Equation VOLTERRA Operator Measure of Weak Noncompactness Fractional Calculus SCHAUDER Fixed Point Theorem
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Tool Condition Monitoring Based on Nonlinear Output Frequency Response Functions and Multivariate Control Chart
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作者 Yufei Gui Ziqiang Lang +1 位作者 Zepeng Liu Hatim Laalej 《Journal of Dynamics, Monitoring and Diagnostics》 2023年第4期243-251,共9页
Tool condition monitoring(TCM)is a key technology for intelligent manufacturing.The objective is to monitor the tool operation status and detect tool breakage so that the tool can be changed in time to avoid significa... Tool condition monitoring(TCM)is a key technology for intelligent manufacturing.The objective is to monitor the tool operation status and detect tool breakage so that the tool can be changed in time to avoid significant damage to workpieces and reduce manufacturing costs.Recently,an innovative TCM approach based on sensor data modelling and model frequency analysis has been proposed.Different from traditional signal feature-based monitoring,the data from sensors are utilized to build a dynamic process model.Then,the nonlinear output frequency response functions,a concept which extends the linear system frequency response function to the nonlinear case,over the frequency range of the tooth passing frequency of the machining process are extracted to reveal tool health conditions.In order to extend the novel sensor data modelling and model frequency analysis to unsupervised condition monitoring of cutting tools,in the present study,a multivariate control chart is proposed for TCM based on the frequency domain properties of machining processes derived from the innovative sensor data modelling and model frequency analysis.The feature dimension is reduced by principal component analysis first.Then the moving average strategy is exploited to generate monitoring variables and overcome the effects of noises.The milling experiments of titanium alloys are conducted to verify the effectiveness of the proposed approach in detecting excessive flank wear of solid carbide end mills.The results demonstrate the advantages of the new approach over conventional TCM techniques and its potential in industrial applications. 展开更多
关键词 intelligent manufacturing multivariate control chart nonlinear Autoregressive with eXogenous Input modelling nonlinear Output Frequency Response functions tool condition monitoring
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Six New Sets of the Non-Elementary Jef-Family-Functions that Are Giving Solutions to Some Second-Order Nonlinear Autonomous ODEs
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作者 Magne Stensland 《Journal of Applied Mathematics and Physics》 2023年第4期1077-1097,共21页
In this paper, we define some new sets of non-elementary functions in a group of solutions x(t) that are sine and cosine to the upper limit of integration in a non-elementary integral that can be arbitrary. We are usi... In this paper, we define some new sets of non-elementary functions in a group of solutions x(t) that are sine and cosine to the upper limit of integration in a non-elementary integral that can be arbitrary. We are using Abel’s methods, described by Armitage and Eberlein. The key is to start with a non-elementary integral function, differentiating and inverting, and then define a set of three functions that belong together. Differentiating these functions twice gives second-order nonlinear ODEs that have the defined set of functions as solutions. We will study some of the second-order nonlinear ODEs, especially those that exhibit limit cycles. Using the methods described in this paper, it is possible to define many other sets of non-elementary functions that are giving solutions to some second-order nonlinear autonomous ODEs. 展开更多
关键词 Non-Elementary functions Second-Order nonlinear Autonomous ODE Limit Cycle
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On the constructions of constant-composition codes from perfect nonlinear functions 被引量:1
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作者 LI Chao LI Qiang LING San 《Science in China(Series F)》 2009年第6期964-973,共10页
A new construction of constant-composition codes based on all known perfect nonlinear functions from Fqm to itself is presented, which provides a kind of unified constructions of constant-composition codes based on al... A new construction of constant-composition codes based on all known perfect nonlinear functions from Fqm to itself is presented, which provides a kind of unified constructions of constant-composition codes based on all known perfect nonlinear functions from F qm to itself.It is proved that the new constant-composition codes are optimal with respect to the Luo-Fu-Vinck-Chen bound, when m is an odd positive integer greater than 1.Finally, we point out that two constructions of constant-composition codes, proposed by Ding Cunsheng et al.in 2005, are equivalent to two special types of the new constant-composition codes. 展开更多
关键词 constant-composition codes perfect nonlinear functions quadratic forms
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Subfield Codes of Linear Codes from Perfect Nonlinear Functions and Their Duals
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作者 Dabin Zheng Xiaoqiang Wang +1 位作者 Yayao Li Mu Yuan 《Communications in Mathematical Research》 CSCD 2022年第2期157-183,共27页
Let F_(p)^(m) be a finite field with p^(m) elements,where p is an odd prime and m is a positive integer.Recently,[17]and[35]determined the weight distributions of subfield codes with the form C f={((T r(a f(x)+b x)+c)... Let F_(p)^(m) be a finite field with p^(m) elements,where p is an odd prime and m is a positive integer.Recently,[17]and[35]determined the weight distributions of subfield codes with the form C f={((T r(a f(x)+b x)+c)_(x∈F_(p)^(m)),T r(a)):a,b∈F_(p)^(m),c∈F_(p)}for f(x)=x^(2) and f(x)=x p k+1,respectively,where Tr(⋅)is the trace function from F_(p)^(m) to F_(p),and k is a nonnegative integer.In this paper,we further investigate the subfield code C f for f(x)being a known perfect nonlinear function over F_(p)^(m) and generalize some results in[17,35].The weight distributions of the constructed codes are determined by applying the theory of quadratic forms and the properties of perfect nonlinear functions over finite fields.In addition,the parameters of the duals of these codes are also determined.Several examples show that some of our codes and their duals have the best known parameters according to the code tables in[16].The duals of some proposed codes are optimal according to the Sphere Packing bound if p≥5. 展开更多
关键词 Subfield code perfect nonlinear function quadratic form weight distribution Sphere Packing bound
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EXISTENCE AND UNIQUENESS OF THE SOLUTION OF A CLASS OF NONLINEAR FUNCTIONAL DIFFERENTIAL EQUATIONS
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作者 Y.A.Fiagbedzi M.A.El-Gebeily 《Annals of Differential Equations》 2000年第4期381-390,共10页
The unicity of the solution, if any, of a class of nonlinear functional differential equations (fde) is established with the help of a transformation. The transformation reduces the fde to an ordinary differential eq... The unicity of the solution, if any, of a class of nonlinear functional differential equations (fde) is established with the help of a transformation. The transformation reduces the fde to an ordinary differential equation. Existence of the solution is established by means of a fixed point theorem. 展开更多
关键词 Golomb’s sequence nonlinear functional differential equation TRANSFORMATION ordinary differential equatio?
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Approximation to Continuous Functions of Several Variables and Nonlinear Functions, Operators by Superpositions of Some Functions of One Variable 被引量:1
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作者 陈天平 《Chinese Science Bulletin》 SCIE EI CAS 1993年第23期1937-1940,共4页
At the Second International Conference of Mathematics, Hilbert raised 23 problems, which promoted the development of mathematics in the 20th century. Among them, the 13th problem can be described as follows: Can the s... At the Second International Conference of Mathematics, Hilbert raised 23 problems, which promoted the development of mathematics in the 20th century. Among them, the 13th problem can be described as follows: Can the solution of any algebraic equation be expressed by superpositions of some functions of one variable? Hilbert conjectured that the solution of the equation x^7+ax^3 +bx^2+cx+1=0, viewed as a function of a, b, c, 展开更多
关键词 APPROXIMATION SUPERPOSITION nonlinear functionALS and OPERATORS neural networks.
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Extended Group Foliation Method and Functional Separation of Variables to Nonlinear Wave Equations 被引量:9
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作者 QU Chang-Zheng ZHANG Shun-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4X期577-582,共6页
Generalized functional separation of variables to nonlinear evolution equations is studied in terms of the extended group foliation method, which is based on the Lie point symmetry method. The approach is applied to n... Generalized functional separation of variables to nonlinear evolution equations is studied in terms of the extended group foliation method, which is based on the Lie point symmetry method. The approach is applied to nonlinear wave equations with variable speed and external force. A complete classification for the wave equation which admits functional separable solutions is presented. Some known results can be recovered by this approach. 展开更多
关键词 非线性波方程 变量功能分离 对称群 扩展群
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Functional Variable Separation for Extended Nonlinear Elliptic Equations 被引量:4
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作者 ZHANG Shun-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3X期385-390,共6页
关键词 非线性椭圆方程 泛函变量分离 广义对称性 扩展
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Expanding the Tanh-Function Method for Solving Nonlinear Equations 被引量:12
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作者 Nassar Hassan Abdel-All Mohamed Abd-Allah Abdel-Razek Abd-Allah Kamel Seddeek 《Applied Mathematics》 2011年第9期1096-1104,共9页
In this paper, using the tanh-function method, we introduce a new approach to solitary wave solutions for solving nonlinear PDEs. The proposed method is based on adding integration constants to the resulting nonlinear... In this paper, using the tanh-function method, we introduce a new approach to solitary wave solutions for solving nonlinear PDEs. The proposed method is based on adding integration constants to the resulting nonlinear ODEs from the nonlinear PDEs using the wave transformation. Also, we use a transformation related to those integration constants. Some examples are considered to find their exact solutions such as KdV- Burgers class and Fisher, Boussinesq and Klein-Gordon equations. Moreover, we discuss the geometric interpretations of the resulting exact solutions. 展开更多
关键词 TANH-function Method nonlinear EQUATIONS SOLITARY WAVES
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A STUDY OF THE CONSTRUCTION OF LYAPUNOV FUNCTION FOR A CLASS OF FOURTH ORDER NONLINEAR SYSTEMS 被引量:1
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作者 梁在中 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第2期195-202,共8页
In the paper Lyapunov function for a fourth order linear system is given and stability of the trivial solutions to a class of.fourth order nonlinear systems is studied
关键词 nonlinear. stability. Lyapunov function
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NONLINEAR PROGRAMMING VIA AN EXACT PENALTY FUNCTION:CONVERGENCE RATE ANALYSIS 被引量:2
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作者 Li Xuequan Li Songren Han Xuili(Department of Applied Mathematics and Applied Software, Central SouthUniversity of Technology, Changsha 410083, China) 《Journal of Central South University》 SCIE EI CAS 1996年第2期102-106,共5页
NONLINEARPROGRAMMINGVIAANEXACTPENALTYFUNCTION:CONVERGENCERATEANALYSISLiXuequanLiSongrenHanXuili(Departmentof... NONLINEARPROGRAMMINGVIAANEXACTPENALTYFUNCTION:CONVERGENCERATEANALYSISLiXuequanLiSongrenHanXuili(DepartmentofAppliedMathematic... 展开更多
关键词 nonlinear PROGRAMMING EXACT PENALTY function algorithm
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Classification and Functional Separable Solutions to Extended Nonlinear Wave Equations 被引量:2
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作者 ZHANG Shun-Li LOU Sen-Yue +1 位作者 QU Chang-Zheng YUE Rui-Hong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4X期589-596,共8页
The generalized conditional symmetry approach is applied to study the variable separation of the extended wave equations. Complete classification of those equations admitting functional separable solutions is obtained... The generalized conditional symmetry approach is applied to study the variable separation of the extended wave equations. Complete classification of those equations admitting functional separable solutions is obtained and exact separable solutions to some of the resulting equations are constructed. 展开更多
关键词 非线性波方程 扩展性 功能分离解 广义性 对称性
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A DUAL-RELAX PENALTY FUNCTION APPROACH FOR SOLVING NONLINEAR BILEVEL PROGRAMMING WITH LINEAR LOWER LEVEL PROBLEM 被引量:7
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作者 万仲平 王广民 吕一兵 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期652-660,共9页
The penalty function method, presented many years ago, is an important nu- merical method for the mathematical programming problems. In this article, we propose a dual-relax penalty function approach, which is signifi... The penalty function method, presented many years ago, is an important nu- merical method for the mathematical programming problems. In this article, we propose a dual-relax penalty function approach, which is significantly different from penalty func- tion approach existing for solving the bilevel programming, to solve the nonlinear bilevel programming with linear lower level problem. Our algorithm will redound to the error analysis for computing an approximate solution to the bilevel programming. The error estimate is obtained among the optimal objective function value of the dual-relax penalty problem and of the original bilevel programming problem. An example is illustrated to show the feasibility of the proposed approach. 展开更多
关键词 nonlinear bilevel programming penalty function approach dual-relax strategy
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Construction of Control Lyapunov Functions for a Class of Nonlinear Systems 被引量:5
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作者 CAI Xiu-Shan HAN Zheng-Zhi WANG Xiao-Dong 《自动化学报》 EI CSCD 北大核心 2006年第5期796-799,共4页
The construction of control Lyapunov functions for a class of nonlinear systems is considered. We develop a method by which a control Lyapunov function for the feedback linearizable part can be constructed systematica... The construction of control Lyapunov functions for a class of nonlinear systems is considered. We develop a method by which a control Lyapunov function for the feedback linearizable part can be constructed systematically via Lyapunov equation. Moreover, by a control Lyapunov function of the feedback linearizable part and a Lyapunov function of the zero dynamics, a control Lyapunov function for the overall nonlinear system is established. 展开更多
关键词 nonlinear systems control Lyapunov functions semiglobal stabilization zero dynamics.
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Universal construction of control Lyapunov functions for a class of nonlinear systems 被引量:1
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作者 Cai Xiushan Wang Xiaodong Zhang Haoran 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期598-602,共5页
A method is developed by which control Lyapunov functions of a class of nonlinear systems can be constructed systematically. Based on the control Lyapunov function, a feedback control is obtained to stabilize the clos... A method is developed by which control Lyapunov functions of a class of nonlinear systems can be constructed systematically. Based on the control Lyapunov function, a feedback control is obtained to stabilize the closed-loop system. In addition, this method is applied to stabilize the Benchmark system. A simulation shows the effectiveness of the method. 展开更多
关键词 control Lyapunov functions nonlinear systems stabilization.
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SVM with Quadratic Polynomial Kernel Function Based Nonlinear Model One-step-ahead Predictive Control 被引量:12
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作者 钟伟民 何国龙 +1 位作者 皮道映 孙优贤 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第3期373-379,共7页
A support vector machine (SVM) with quadratic polynomial kernel function based nonlinear model one-step-ahead predictive controller is presented. The SVM based predictive model is established with black-box identifica... A support vector machine (SVM) with quadratic polynomial kernel function based nonlinear model one-step-ahead predictive controller is presented. The SVM based predictive model is established with black-box identification method. By solving a cubic equation in the feature space, an explicit predictive control law is obtained through the predictive control mechanism. The effect of controller is demonstrated on a recognized benchmark problem and on the control of continuous-stirred tank reactor (CSTR). Simulation results show that SVM with quadratic polynomial kernel function based predictive controller can be well applied to nonlinear systems, with good performance in following reference trajectory as well as in disturbance-rejection. 展开更多
关键词 SVM 二次方程式 多项式 非线性模型 预测模型 运算法则 控制论
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Synchronizing spatiotemporal chaos in the coupled map lattices using nonlinear feedback functions 被引量:1
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作者 FangJin-Qing MKAli 《Nuclear Science and Techniques》 SCIE CAS CSCD 1997年第3期129-135,共7页
SynchronizingspatiotemporalchaosinthecoupledmaplaticesusingnonlinearfedbackfunctionsTheworkissupportedbyfund... SynchronizingspatiotemporalchaosinthecoupledmaplaticesusingnonlinearfedbackfunctionsTheworkissupportedbyfundingtoFangJinQi... 展开更多
关键词 浑沌 同步时空浑沌 非线性反馈函数
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