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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 nonlinear functional equation nonlinear Voherra integral equation reproducing kernel
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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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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 equation
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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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Dynamics Analysis of Active Variable Stiffness Vibration Isolator for Whole-Spacecraft Systems Based on Nonlinear Output Frequency Response Functions 被引量:3
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作者 Kefan Xu Yewei Zhang +2 位作者 Yunpeng Zhu Jian Zang Liqun Chen 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2020年第6期731-743,共13页
In order to improve the harsh dynamic environment experienced by heavy rockets during different external excitations,this study presents a novel active variable stiffness vibration isolator(AVS-VI)used as the vibratio... In order to improve the harsh dynamic environment experienced by heavy rockets during different external excitations,this study presents a novel active variable stiffness vibration isolator(AVS-VI)used as the vibration isolation device to reduce excessive vibration of the whole-spacecraft isolation system.The AVS-VI is composed of horizontal stiffness spring,positive stiffness spring,parallelogram linkage mechanism,piezoelectric actuator,acceleration sensor,viscoelastic damping,and PID active controller.Based on the AVS-VI,the generalized vibration transmissibility determined by the nonlinear output frequency response functions and the energy absorption rate is applied to analyze the isolation performance of the whole-spacecraft system with AVS-VI.The AVS-VI can conduct adaptive vibration suppression with variable stiffness to the whole-spacecraft system,and the analysis results indicate that the AVS-VI is efTective in reducing the extravagant vibration of the whole-spacecraft system,where the vibration isolation is decreased up to above 65%under different acceleration excitations.Finally,different parameters of AVS-VI are considered to optimize the whole-spacecraft system based on the generalized vibration transmissibility and the energy absorption rate. 展开更多
关键词 Vibration isolation Active variable stiffness vibration isolator nonlinear output frequency response functions(NOFRFs) TRANSMISSIBILITY
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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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Properties of Certain Nonlinear Integral Operator Associated with Janowski Starlike and Convex Functions 被引量:1
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作者 Liangpeng XIONG 《Journal of Mathematical Research with Applications》 CSCD 2016年第4期432-440,共9页
In this paper, we consider a general nonlinear integral operator Hαi, βi ( f1,..., fn ; g1,..., gn)(z). Some results including coefficient problems, univalency condition and radius of convexity for this integral... In this paper, we consider a general nonlinear integral operator Hαi, βi ( f1,..., fn ; g1,..., gn)(z). Some results including coefficient problems, univalency condition and radius of convexity for this integral operator are given. Furthermore, we discuss the mapping properties between Hαi,βi (f1 , fn, ; g1,..., gn)(z) and subclasses of analytic functions with bounded boundary rotation. The same subjects for some corresponding classes are shown upon specializing the parameters in our main results. 展开更多
关键词 analytic functions Janowski functions nonlinear integral operators functions with bounded boundary rotation SUBORDINATION
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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 SouthUniversity of Technology, Changsha 410083, China) 《Journal of Central South University》 SCIE EI CAS 1996年第2期102-106,共5页
The algorithm proposed by T. F. Colemen and A. R. Conn is improved in this paper, and the improved algorithm can solve nonlinear programming problem with quality constraints. It is shown that the improved algorithm po... The algorithm proposed by T. F. Colemen and A. R. Conn is improved in this paper, and the improved algorithm can solve nonlinear programming problem with quality constraints. It is shown that the improved algorithm possesses global convergence, and under some conditions, it possesses locally supperlinear convergence. 展开更多
关键词 nonlinear PROGRAMMING EXACT PENALTY function algorithm
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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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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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On the Role of Bond Function in Nonlinear Optical Property Calculations for HF,HCI,LiH,H_(2)O and NH_(3) 被引量:1
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作者 Zhi-ru., TAO Fu-ming, PAN Yuh-Kang, FENG Ji-Kang, SUN Chia-Chung(Department of Chemistry, Jilin University, Changchun, 130023, China Department of Chemiststry, Harvard University, Cambraidge, MA 02138 , USA Department of Chemistry, Boston College, Ches 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1997年第3期240-243,共4页
Dond function basis sets have been used to calculate the molecular nonlinear optical properties which include hyperpolarizability βo , polarizability ao , and dipole moment μo for six molecules. The calculations at ... Dond function basis sets have been used to calculate the molecular nonlinear optical properties which include hyperpolarizability βo , polarizability ao , and dipole moment μo for six molecules. The calculations at the fourth-order Moller-Plesset approximation (MP4) have recovered more than 90% of the experimental values βo , comparecl to that as low as 75% by the other authors. The calculated values of αo and iuo are also in good agreement with those of experiments and superior to that from other work. It is shown that the bond functions improve the calculated results at SCF level and especially at the level of the correction of electronic correlation (MP2 and MP4). 展开更多
关键词 Bond function nonlinear optical property MP4 calculation
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Direct adaptive control for nonlinear uncertain system based on control Lyapunov function method 被引量:1
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作者 Chen Yimei Han Zhengzhi Tang Houjun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期619-623,共5页
The problem of adaptive stabilization of a class of multi-input nonlinear systems with unknown parameters both in the state vector-field and the input vector-field has been considered. By employing the control Lyapuno... The problem of adaptive stabilization of a class of multi-input nonlinear systems with unknown parameters both in the state vector-field and the input vector-field has been considered. By employing the control Lyapunov function method, a direct adaptive controller is designed to complete the global adaptive stability of the uncertain system. At the same time, the controller is also verified to possess the optimality. Example and simulations are provided to illustrate the effectiveness of the proposed method. 展开更多
关键词 adaptive control control Lyapunov function nonlinear uncertain system optimality.
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Generalized Extended tanh-function Method for Traveling Wave Solutions of Nonlinear Physical Equations 被引量:6
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作者 CHANG JING GAO YI-XIAN AND CAI HUA 《Communications in Mathematical Research》 CSCD 2014年第1期60-70,共11页
In this paper, the generalized extended tanh-function method is used for constructing the traveling wave solutions of nonlinear evolution equations. We choose Fisher's equation, the nonlinear schr&#168;odinger equat... In this paper, the generalized extended tanh-function method is used for constructing the traveling wave solutions of nonlinear evolution equations. We choose Fisher's equation, the nonlinear schr&#168;odinger equation to illustrate the validity and ad-vantages of the method. Many new and more general traveling wave solutions are obtained. Furthermore, this method can also be applied to other nonlinear equations in physics. 展开更多
关键词 generalized tanh-function method nonlinear Schrodinger equation Fisher's equation
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New Application of bond Function Basis Sets──ab initio Calculations of Nonlinear OpticalProperties of Ch_4-1nF_n(n=1,2,3) 被引量:1
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作者 Li Zhi-ru, TAO Fu-ming, PAN Yuh-kang., FENG Ji-kang, WU Di., HUANG Xu-rid , SUN Ghia-Chung.(Department of Chemistry, Jilin University, Changchun, 130023 , CAina b $$Department of Chemistry, Harvard University, Chmberidge,MA 02138 , USA/Department of Chem 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1997年第3期235-239,共5页
On the basis of adding the bond functions (3s 3p 2d) to the basis sets 6-311G ( 2d 2p ) for increasing the efficiency of the basis sets , we have carried out the MP2 calculations of nonlinear optical properties includ... On the basis of adding the bond functions (3s 3p 2d) to the basis sets 6-311G ( 2d 2p ) for increasing the efficiency of the basis sets , we have carried out the MP2 calculations of nonlinear optical properties includintg dipole moment uo,polarizibili- ty ao and hyperpolarizability , for CH4-nFn (n = 1 , 2 , 3). The results are in good a- greement with those of experimentsl The roles of the bond functions in the calcula- tions are shown , i. e., the improved values of the properties are about 2%-7% at the SCF level and about 6%-30% at the correlated level (MP2). It is shown that the more important role of the bond functions in calculating is the im- provement of the effects of the corrections of electronic correlations and the increase of the effects is in the order of. In addition , it is also shown that the cal-, culated value of a property does not change with the bond-function location in our calculations except for the regions close to the nuclei in a molecule. 展开更多
关键词 Bond function MP2 nonlinear optical property
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