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Darboux transformation,positon solution,and breather solution of the third-order flow Gerdjikov–Ivanov equation
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作者 Shuzhi Liu Ning-Yi Li +1 位作者 Xiaona Dong Maohua Li 《Chinese Physics B》 2025年第1期195-202,共8页
The third-order flow Gerdjikov–Ivanov(TOFGI)equation is studied,and the Darboux transformation(DT)is used to obtain the determinant expression of the solution of this equation.On this basis,the soliton solution,ratio... The third-order flow Gerdjikov–Ivanov(TOFGI)equation is studied,and the Darboux transformation(DT)is used to obtain the determinant expression of the solution of this equation.On this basis,the soliton solution,rational solution,positon solution,and breather solution of the TOFGI equation are obtained by taking zero seed solution and non-zero seed solution.The exact solutions and dynamic properties of the Gerdjikov–Ivanov(GI)equation and the TOFGI equation are compared in detail under the same conditions,and it is found that there are some differences in the velocities and trajectories of the solutions of the two equations. 展开更多
关键词 third-order flow Gerdjikov-Ivanov equation solitons positons BREATHERS
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Hojman's theorem of the third-order ordinary differential equation
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作者 吕洪升 张宏彬 顾书龙 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第8期3135-3138,共4页
This paper extends Hojman's conservation law to the third-order differential equation. A new conserved quantity is constructed based on the Lie group of transformation generators of the equations of motion. The gener... This paper extends Hojman's conservation law to the third-order differential equation. A new conserved quantity is constructed based on the Lie group of transformation generators of the equations of motion. The generators contain variations of the time and generalized coordinates. Two independent non-trivial conserved quantities of the third-order ordinary differential equation are obtained. A simple example is presented to illustrate the applications of the results. 展开更多
关键词 third-order ordinary differential equation Lie symmetry Hojman's conservation law
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Prediction of ILI following the COVID-19 pandemic in China by using a partial differential equation
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作者 Xu Zhang Yu-Rong Song Ru-Qi Li 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期118-128,共11页
The COVID-19 outbreak has significantly disrupted the lives of individuals worldwide.Following the lifting of COVID-19 interventions,there is a heightened risk of future outbreaks from other circulating respiratory in... The COVID-19 outbreak has significantly disrupted the lives of individuals worldwide.Following the lifting of COVID-19 interventions,there is a heightened risk of future outbreaks from other circulating respiratory infections,such as influenza-like illness(ILI).Accurate prediction models for ILI cases are crucial in enabling governments to implement necessary measures and persuade individuals to adopt personal precautions against the disease.This paper aims to provide a forecasting model for ILI cases with actual cases.We propose a specific model utilizing the partial differential equation(PDE)that will be developed and validated using real-world data obtained from the Chinese National Influenza Center.Our model combines the effects of transboundary spread among regions in China mainland and human activities’impact on ILI transmission dynamics.The simulated results demonstrate that our model achieves excellent predictive performance.Additionally,relevant factors influencing the dissemination are further examined in our analysis.Furthermore,we investigate the effectiveness of travel restrictions on ILI cases.Results can be used to utilize to mitigate the spread of disease. 展开更多
关键词 partial differential equations INFLUENZA SIS model PREDICTION
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THE EXACT MEROMORPHIC SOLUTIONS OF SOME NONLINEAR DIFFERENTIAL EQUATIONS
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作者 刘慧芳 毛志强 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期103-114,共12页
We find the exact forms of meromorphic solutions of the nonlinear differential equations■,n≥3,k≥1,where q,Q are nonzero polynomials,Q■Const.,and p_(1),p_(2),α_(1),α_(2)are nonzero constants withα_(1)≠α_(2).Co... We find the exact forms of meromorphic solutions of the nonlinear differential equations■,n≥3,k≥1,where q,Q are nonzero polynomials,Q■Const.,and p_(1),p_(2),α_(1),α_(2)are nonzero constants withα_(1)≠α_(2).Compared with previous results on the equation p(z)f^(3)+q(z)f"=-sinα(z)with polynomial coefficients,our results show that the coefficient of the term f^((k))perturbed by multiplying an exponential function will affect the structure of its solutions. 展开更多
关键词 Nevanlinna theory nonlinear differential equations meromorphic functions entire functions
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Continuous-Time Channel Prediction Based on Tensor Neural Ordinary Differential Equation
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作者 Mingyao Cui Hao Jiang +2 位作者 Yuhao Chen Yang Du Linglong Dai 《China Communications》 SCIE CSCD 2024年第1期163-174,共12页
Channel prediction is critical to address the channel aging issue in mobile scenarios.Existing channel prediction techniques are mainly designed for discrete channel prediction,which can only predict the future channe... Channel prediction is critical to address the channel aging issue in mobile scenarios.Existing channel prediction techniques are mainly designed for discrete channel prediction,which can only predict the future channel in a fixed time slot per frame,while the other intra-frame channels are usually recovered by interpolation.However,these approaches suffer from a serious interpolation loss,especially for mobile millimeter-wave communications.To solve this challenging problem,we propose a tensor neural ordinary differential equation(TN-ODE)based continuous-time channel prediction scheme to realize the direct prediction of intra-frame channels.Specifically,inspired by the recently developed continuous mapping model named neural ODE in the field of machine learning,we first utilize the neural ODE model to predict future continuous-time channels.To improve the channel prediction accuracy and reduce computational complexity,we then propose the TN-ODE scheme to learn the structural characteristics of the high-dimensional channel by low-dimensional learnable transform.Simulation results show that the proposed scheme is able to achieve higher intra-frame channel prediction accuracy than existing schemes. 展开更多
关键词 channel prediction massive multipleinput-multiple-output millimeter-wave communications ordinary differential equation
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Pseudo S-Asymptotically(ω,c)-Periodic Solutions to Fractional Differential Equations of Sobolev Type
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作者 MAO Hang-ning CHANG Yong-kui 《Chinese Quarterly Journal of Mathematics》 2024年第3期295-306,共12页
In this paper,we firstly recall some basic results on pseudo S-asymptotically(ω,c)-periodic functions and Sobolev type fractional differential equation.We secondly investigate some existence of pseudo S-asymptotical... In this paper,we firstly recall some basic results on pseudo S-asymptotically(ω,c)-periodic functions and Sobolev type fractional differential equation.We secondly investigate some existence of pseudo S-asymptotically(ω,c)-periodic solutions for a semilinear fractional differential equations of Sobolev type.We finally present a simple example. 展开更多
关键词 Pseudo S-asymptotically(ω c)-periodic functions Evolution equations Sobolev type Fractional differential equations Existence and uniqueness
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The Hyers-Ulam Stability and Hyers-Ulam Instability for Some Nonhomogeneous Ordinary Differential Equations
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作者 DENG Jing-tao 《Chinese Quarterly Journal of Mathematics》 2024年第4期420-430,共11页
In this paper,we get a necessary and sufficient condition such that a class of differential inequalities hold.Using this necessary and sufficient condition,we prove that a class of first order nonhomogeneous ordinary ... In this paper,we get a necessary and sufficient condition such that a class of differential inequalities hold.Using this necessary and sufficient condition,we prove that a class of first order nonhomogeneous ordinary differential equations have the Hyers-Ulam stability.And then,we prove that some first order nonhomogeneous ordinary differential equations and some second order nonhomogeneous ordinary differential equations do not have the Hyers-Ulam instability under some suitable conditions. 展开更多
关键词 Hyers-Ulam stability Hyers-Ulam instability Ordinary differential equations Necessary and sufficient condition
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Oscillation of Systems of Parabolic Differential Equations with Deviating Arguments 被引量:1
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作者 邓立虎 王宏洲 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 2001年第1期12-16,共5页
To study a class of boundary value problems of parabolic differential equations with deviating arguments, averaging technique, Green’s formula and symbol function sign(·) are used. The multi dimensional problem... To study a class of boundary value problems of parabolic differential equations with deviating arguments, averaging technique, Green’s formula and symbol function sign(·) are used. The multi dimensional problem was reduced to a one dimensional oscillation problem for ordinary differential equations or inequalities. Two oscillatory criteria of solutions for systems of parabolic differential equations with deviating arguments are obtained. 展开更多
关键词 systems of parabolic differential equations boundary value problem deviating arguments OSCILLATION
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Asymptotic Stability in the Large of Zero Solution of Second Order Nonlinear Differential Equation 被引量:2
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作者 王德利 谭远顺 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第2期13-16,共4页
There are many works on the asymptotic stability of second dimensional nonlinear differential equation. In particular, these results only concern with the system which includes one or two terms, whereas few works conc... There are many works on the asymptotic stability of second dimensional nonlinear differential equation. In particular, these results only concern with the system which includes one or two terms, whereas few works concern with system which includes more than two terms. In this paper, system which includes four nonlinear terms are studies. We obtain the global asymptotic stability of zero solution, and discard the condition which require the Liapunov function trends to infinity, and only require that the positive orbit is bounded. 展开更多
关键词 nonlinear differential equation zero solution globally asymptotic stability
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Existence of Periodic Solutions for Generalized Liénard-Typed Functional Differential Equations
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作者 贺小明 葛渭高 单文锐 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期325-328,共4页
The existence of periodic solutions for a kind of generalized Liénard typed functional differential equation is studied. By means of the continuation theorem of coincidence degree theory, existence criteria are ... The existence of periodic solutions for a kind of generalized Liénard typed functional differential equation is studied. By means of the continuation theorem of coincidence degree theory, existence criteria are established for the existence of periodic solutions and some previous results are extended. 展开更多
关键词 functional differential equation periodic solution coincidence degree
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Existence of Periodic Solutions of Nonlinear Neutral Differential Equation with Deviating Argument
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作者 任景莉 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 2002年第4期439-443,共5页
Existence criteria is established for the periodic solution of the nonlinear neutral delay differential equation x′(t)=f(t,x(t),x(t-τ 1(t)),x′(t-τ 2(t)))+p(t) by means of an abstract continuous theorem of k-set ... Existence criteria is established for the periodic solution of the nonlinear neutral delay differential equation x′(t)=f(t,x(t),x(t-τ 1(t)),x′(t-τ 2(t)))+p(t) by means of an abstract continuous theorem of k-set contractive operator and some analysis technique. 展开更多
关键词 neutral delay differential equation periodic solution Fredholm operator k-set contractive operator
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The Global Solutions of Impulsive Retarded Functional Differential Equations
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作者 王儒智 孙建安 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第3期94-99,共6页
In this paper, we present some results on the existence of the golbal solutions of nonlinear impulsive retarded functional differential equations.
关键词 Fréchet spaces Tychonoff fixed point Theorem impulsive retarded functional differential equations
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Existence of Many and Infinitely Many Periodic Solutions for Some Types of Differential Delay Equations
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作者 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 1993年第1期5-14,共10页
J.Kaplan and J.Yorke's method is extended to establish the exis- tence of many and infinitely many periodic solutions for the DDEs (t) =±f(x(t-1))±f(x(t-2))and (t)=±f(x(t-1).
关键词 difference differential equation periodic solution SYMMETRY
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On Algebroid Solutions of Generalized Complex Differential Equations
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作者 高凌云 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第1期20-25,共6页
Using the Nevanlinna theory of the value distribution of meromorphic functions, we investigate the existence problem of admissible algebroid solutions of generalized complex algebraic differential equations and obtain... Using the Nevanlinna theory of the value distribution of meromorphic functions, we investigate the existence problem of admissible algebroid solutions of generalized complex algebraic differential equations and obtain some results. 展开更多
关键词 algebroid functions admissible solution generalized differential equations
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THE BASIC THEORY OF SOLUTIONS OF FUNCTIONAL DIFFERENTIAL EQUATIONS WITH BOUNDED DELAY IN THE SPACE OF INTEGRABLE FUNCTIONS
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作者 刘永清 李远清 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 1997年第7期67-73,共7页
在可积函数空间中讨论有界滞量泛函微分方程,建立其解的基本理论,包括解的存在性,唯一性及延展性。
关键词 有界滞量的泛函微分方程 存在性 唯一性 延展性 可积函数空间
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ON THE GROWTH OF SOLUTIONS OF A CLASS OF HIGHER ORDER DIFFERENTIAL EQUATIONS 被引量:28
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作者 陈宗煊 孙光镐 《Acta Mathematica Scientia》 SCIE CSCD 2004年第1期52-60,共9页
In this paper, authors investigate the order of growth and the hyper order of solutions of a class of the higher order linear differential equation, and improve results of M. Ozawa, G. Gundersen and J.K. Langley, Li C... In this paper, authors investigate the order of growth and the hyper order of solutions of a class of the higher order linear differential equation, and improve results of M. Ozawa, G. Gundersen and J.K. Langley, Li Chun-hong. 展开更多
关键词 differential equation entire function HYPER-ORDER
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New exact solutions to some difference differential equations 被引量:15
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作者 王振 张鸿庆 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第10期2210-2215,共6页
In this paper, we use our method to solve the extended Lotka-Volterra equation and discrete KdV equation. With the help of Maple, we obtain a number of exact solutions to the two equations including soliton solutions ... In this paper, we use our method to solve the extended Lotka-Volterra equation and discrete KdV equation. With the help of Maple, we obtain a number of exact solutions to the two equations including soliton solutions presented by hyperbolic functions of sinh and cosh, periodic solutions presented by trigonometric functions of sin and cos, and rational solutions. This method can be used to solve some other nonlinear difference-differential equations. 展开更多
关键词 difference differential equation soliton solutions Lotka-Volterra equation discrete KdV equation
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THE GROWTH OF SOLUTIONS OF SYSTEMS OF COMPLEX NONLINEAR ALGEBRAIC DIFFERENTIAL EQUATIONS 被引量:19
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作者 高凌云 《Acta Mathematica Scientia》 SCIE CSCD 2010年第3期932-938,共7页
We investigate the problem of growth order of solutions of a type of systems of non-linear algebraic differential equations, and extend some results of the growth order of solutions of algebraic differential equations... We investigate the problem of growth order of solutions of a type of systems of non-linear algebraic differential equations, and extend some results of the growth order of solutions of algebraic differential equations to systems of algebraic differential equations. 展开更多
关键词 Growth order algebraic differential equations entire function
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On the Conjecture of Gackstatter and Laine Concerning Algebraic Differential Equations
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作者 邱青 韩国平 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第2期16-21,共0页
In this paper we investigate the form of a class of complex differential equations withadmissible solution and obtain a main result.
关键词 admissible solution form of complex differential equations the value distribution
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OSCILLATORY BEHAVIOUR OF A CLASS OF NONLINEAR DIFFERENTIAL EQUATIONS OF THIRD ORDER 被引量:10
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作者 A. Tiryaki Department of Mathematics, Gazi University Faculty of Arts and Sciences Teknik Okullar, 06500 Ankara, Turkey S. (Yaman) Pasinlio■u Department of Mathematics, Hacettepe University, 06532 Beytepe, Ankara, Turkey 《Acta Mathematica Scientia》 SCIE CSCD 2001年第2期182-188,共7页
This paper investigates the oscillatory and nonoscillatory behaviour of solu- tions of a class of third order nonlinear differential equations. Results extend and improve some known results in the literature.
关键词 Oscillatory solution nonoscillatory solution behaviour of solution nonlinear differential equation
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