We establish a new Kamenev-type theorem for a class of second-order nonlinear damped delay dynamic equations on a time scale by using the generalized Riccati transformation technique. The criterion obtained improves r...We establish a new Kamenev-type theorem for a class of second-order nonlinear damped delay dynamic equations on a time scale by using the generalized Riccati transformation technique. The criterion obtained improves related contributions to the subject. An example is provided to illustrate assumptions in our theorem are less restrictive.展开更多
We establish new Kamenev-type oscillation criteria for the half-linear partial differential equation with damping div(A(x)|| u||^p-2 u)+〈b(x),|| u||^p-2 u〉+c(x)|u|^p-2u=0(E)under quite general ...We establish new Kamenev-type oscillation criteria for the half-linear partial differential equation with damping div(A(x)|| u||^p-2 u)+〈b(x),|| u||^p-2 u〉+c(x)|u|^p-2u=0(E)under quite general conditions. These results are extensions of the recent results developed by Sun [Y.C. Sun, New Kamenev-type oscillation criteria of second order nonlinear differential equations with damping, J. Math. Anal. Appl. 291 (2004) 341-351] for second order ordinary differential equations in a natural way, and improve some existing results in the literature. As applications, we illustrate our main results using two different types of half-linear partial differential equations.展开更多
Firstly, a priori estimates are obtained for the existence and uniqueness of solutions of two dimensional KDV equations, and prove the existence of the global attractor, finally get the upper bound estimation of the H...Firstly, a priori estimates are obtained for the existence and uniqueness of solutions of two dimensional KDV equations, and prove the existence of the global attractor, finally get the upper bound estimation of the Hausdorff and fractal dimension of attractors.展开更多
In this paper,a new approach is devoted to find novel analytical and approximate solutions to the damped quadratic nonlinear Helmholtz equation(HE)in terms of the Weiersrtrass elliptic function.The exact solution for ...In this paper,a new approach is devoted to find novel analytical and approximate solutions to the damped quadratic nonlinear Helmholtz equation(HE)in terms of the Weiersrtrass elliptic function.The exact solution for undamped HE(integrable case)and approximate/semi-analytical solution to the damped HE(non-integrable case)are given for any arbitrary initial conditions.As a special case,the necessary and sufficient condition for the integrability of the damped HE using an elementary approach is reported.In general,a new ansatz is suggested to find a semi-analytical solution to the non-integrable case in the form of Weierstrass elliptic function.In addition,the relation between the Weierstrass and Jacobian elliptic functions solutions to the integrable case will be derived in details.Also,we will make a comparison between the semi-analytical solution and the approximate numerical solutions via using Runge-Kutta fourth-order method,finite difference method,and homotopy perturbation method for the first-two approximations.Furthermore,the maximum distance errors between the approximate/semi-analytical solution and the approximate numerical solutions will be estimated.As real applications,the obtained solutions will be devoted to describe the characteristics behavior of the oscillations in RLC series circuits and in various plasma models such as electronegative complex plasma model.展开更多
In this paper, the problem of determining the largest possible set of symmetries for an important nonlinear dynamical system: the two-dimensional damped Kuramoto-Sivashinsky ((21)) DKS ) equation is studied. By ...In this paper, the problem of determining the largest possible set of symmetries for an important nonlinear dynamical system: the two-dimensional damped Kuramoto-Sivashinsky ((21)) DKS ) equation is studied. By applying the basic Lie symmetry method for the (217)) DKS equation, the classical Lie point symmetry operators are obtained. Also, the optimal system of one-dimensional subalgebras of the equation is constructed. The Lie invariants as well as similarity reduced equations corresponding to infinitesimal symmetries are obtained. The nonclassicaJ symmetries of the (2D) DKS equation are also investigated.展开更多
In this work,the head-on collisions of the non-stationary dissipative soliton in ultracold neutral plasmas(UNPs)are investigated.The extended Poincare-Lighthill-Kuo(PLK)approach is adopted for reducing the fluid equat...In this work,the head-on collisions of the non-stationary dissipative soliton in ultracold neutral plasmas(UNPs)are investigated.The extended Poincare-Lighthill-Kuo(PLK)approach is adopted for reducing the fluid equations of the UNPs to two-counterpropagating damped Korteweg-de Vries(dKdV)equations.The dKdV equation is not an integrable Hamiltonian system,i.e.,does not have an exact solution.Thus,one of the main goal of this paper is to find a new general approximate analytical solution to the dKdV equation for investigating the mechanism of the propagation and interaction of the non-stationary dissipative solitons.The residual error is estimated for checking the accuracy of the new obtained solution.The approximate analytical soliton solutions are adopted for deriving the temporal phase shifts after the collision.The impact of physical parameters on the nonstationary dissipative soliton profile and the temporal phase shifts is discussed.The obtained results will contribute to understand the mechanism of propagation and interaction of many nonlinear phenomena in different nonlinear mediums such as ocean,sea,optical fiber,plasma physics,etc.展开更多
Abstract This paper is concerned with the initial-boundary value problem for damped wave equations with a nonlinear convection term in the half space R+{utt-txx+ut+f(u)x=0,t〉0,x∈R+,u(0,x)=u0(x)→u+,asx→...Abstract This paper is concerned with the initial-boundary value problem for damped wave equations with a nonlinear convection term in the half space R+{utt-txx+ut+f(u)x=0,t〉0,x∈R+,u(0,x)=u0(x)→u+,asx→+∞,ut(0,x)=u1(x),u(t,0)=ub.For the non-degenerate case f](u+) 〈 0, it is shown in [1] that the above initialboundary value problem admits a unique global solution u(t,x) which converges to the stationary wave φ(x) uniformly in x ∈ R+ as time tends to infinity provided that the initial perturbation and/or the strength of the stationary wave are sufficiently small. Moreover, by using the space-time weighted energy method initiated by Kawashima and Matsumura [2], the convergence rates (including the algebraic convergence rate and the exponential convergence rate) of u(t, x) toward φ(x) are also obtained in [1]. We note, however, that the analysis in [1] relies heavily on the assumption that f'(ub) 〈 0. The main purpose of this paper is devoted to discussing the case of f'(ub)= 0 and we show that similar results still hold for such a case. Our analysis is based on some delicate energy estimates.展开更多
Instead of the L^p estimates,we study the modulation space estimates for the solution to the damped wave equation.Decay properties for both the linear and semilinear equations are obtained.The estimates in modulation ...Instead of the L^p estimates,we study the modulation space estimates for the solution to the damped wave equation.Decay properties for both the linear and semilinear equations are obtained.The estimates in modulation space differ in many aspects from those in L^p space.展开更多
A novel approximate analytical solution to the linear damped Kawahara equation using a suitable hypothesis is reported for the first time.Based on the exact solutions(such as solitary waves,cnoidal waves,etc.)of the u...A novel approximate analytical solution to the linear damped Kawahara equation using a suitable hypothesis is reported for the first time.Based on the exact solutions(such as solitary waves,cnoidal waves,etc.)of the undamped Kawahara equation,the dissipative nonlinear structures like dissipative solitons and cnoidal waves are investigated.The obtained solution is considered a general solution,i.e.,it can be applied for studying the properties of all dissipative traveling waves described by the linear damped Kawahara equation.Our technique is not limited to solve the linear damped Kawahara equation only,but it can be used for solving a large number of non-integrable evolution equations related to the realistic natural phenomena.Moreover,the maximum global residual error in the whole space-time domain is estimated for checking the accuracy of the obtained solutions.The obtained solutions can help many researchers in explaining the ambiguities about the mechanisms of propagation of nonlinear waves in complex systems such as seas,oceans,plasma physics,and much more.展开更多
In this article,the main objective is to employ the homotopy perturbation method(HPM)as an alternative to classical perturbation methods for solving nonlinear equations having periodic coefficients.As a simple example...In this article,the main objective is to employ the homotopy perturbation method(HPM)as an alternative to classical perturbation methods for solving nonlinear equations having periodic coefficients.As a simple example,the nonlinear damping Mathieu equation has been investigated.In this investigation,two nonlinear solvability conditions are imposed.One of them was imposed in the first-order homotopy perturbation and used to study the stability behavior at resonance and non-resonance cases.The next level of the perturbation approaches another solvability condition and is applied to obtain the unknowns become clear in the solution for the firstorder solvability condition.The approach assumed here is so significant for solving many parametric nonlinear equations that arise within the engineering and nonlinear science.展开更多
基金supported by the Applied Mathematics Enhancement Program of Linyi University
文摘We establish a new Kamenev-type theorem for a class of second-order nonlinear damped delay dynamic equations on a time scale by using the generalized Riccati transformation technique. The criterion obtained improves related contributions to the subject. An example is provided to illustrate assumptions in our theorem are less restrictive.
基金Supported by the National Natural Science Foundation of Guangdong Province under Grant (No.8451063101000730)
文摘We establish new Kamenev-type oscillation criteria for the half-linear partial differential equation with damping div(A(x)|| u||^p-2 u)+〈b(x),|| u||^p-2 u〉+c(x)|u|^p-2u=0(E)under quite general conditions. These results are extensions of the recent results developed by Sun [Y.C. Sun, New Kamenev-type oscillation criteria of second order nonlinear differential equations with damping, J. Math. Anal. Appl. 291 (2004) 341-351] for second order ordinary differential equations in a natural way, and improve some existing results in the literature. As applications, we illustrate our main results using two different types of half-linear partial differential equations.
文摘Firstly, a priori estimates are obtained for the existence and uniqueness of solutions of two dimensional KDV equations, and prove the existence of the global attractor, finally get the upper bound estimation of the Hausdorff and fractal dimension of attractors.
基金Taif University Researchers Supporting Project number(TURSP-2020/275),Taif University,Taif,Saudi Arabia.
文摘In this paper,a new approach is devoted to find novel analytical and approximate solutions to the damped quadratic nonlinear Helmholtz equation(HE)in terms of the Weiersrtrass elliptic function.The exact solution for undamped HE(integrable case)and approximate/semi-analytical solution to the damped HE(non-integrable case)are given for any arbitrary initial conditions.As a special case,the necessary and sufficient condition for the integrability of the damped HE using an elementary approach is reported.In general,a new ansatz is suggested to find a semi-analytical solution to the non-integrable case in the form of Weierstrass elliptic function.In addition,the relation between the Weierstrass and Jacobian elliptic functions solutions to the integrable case will be derived in details.Also,we will make a comparison between the semi-analytical solution and the approximate numerical solutions via using Runge-Kutta fourth-order method,finite difference method,and homotopy perturbation method for the first-two approximations.Furthermore,the maximum distance errors between the approximate/semi-analytical solution and the approximate numerical solutions will be estimated.As real applications,the obtained solutions will be devoted to describe the characteristics behavior of the oscillations in RLC series circuits and in various plasma models such as electronegative complex plasma model.
文摘In this paper, the problem of determining the largest possible set of symmetries for an important nonlinear dynamical system: the two-dimensional damped Kuramoto-Sivashinsky ((21)) DKS ) equation is studied. By applying the basic Lie symmetry method for the (217)) DKS equation, the classical Lie point symmetry operators are obtained. Also, the optimal system of one-dimensional subalgebras of the equation is constructed. The Lie invariants as well as similarity reduced equations corresponding to infinitesimal symmetries are obtained. The nonclassicaJ symmetries of the (2D) DKS equation are also investigated.
基金funded by the Deanship of Scientific Research at Princess Nourah bint Abdulrahman University through the Fasttrack Research Funding Program.
文摘In this work,the head-on collisions of the non-stationary dissipative soliton in ultracold neutral plasmas(UNPs)are investigated.The extended Poincare-Lighthill-Kuo(PLK)approach is adopted for reducing the fluid equations of the UNPs to two-counterpropagating damped Korteweg-de Vries(dKdV)equations.The dKdV equation is not an integrable Hamiltonian system,i.e.,does not have an exact solution.Thus,one of the main goal of this paper is to find a new general approximate analytical solution to the dKdV equation for investigating the mechanism of the propagation and interaction of the non-stationary dissipative solitons.The residual error is estimated for checking the accuracy of the new obtained solution.The approximate analytical soliton solutions are adopted for deriving the temporal phase shifts after the collision.The impact of physical parameters on the nonstationary dissipative soliton profile and the temporal phase shifts is discussed.The obtained results will contribute to understand the mechanism of propagation and interaction of many nonlinear phenomena in different nonlinear mediums such as ocean,sea,optical fiber,plasma physics,etc.
基金This work was supported by two grants from the National Natural Science Foundation of China under contracts 10431060 and 10329101 respectively.
文摘Abstract This paper is concerned with the initial-boundary value problem for damped wave equations with a nonlinear convection term in the half space R+{utt-txx+ut+f(u)x=0,t〉0,x∈R+,u(0,x)=u0(x)→u+,asx→+∞,ut(0,x)=u1(x),u(t,0)=ub.For the non-degenerate case f](u+) 〈 0, it is shown in [1] that the above initialboundary value problem admits a unique global solution u(t,x) which converges to the stationary wave φ(x) uniformly in x ∈ R+ as time tends to infinity provided that the initial perturbation and/or the strength of the stationary wave are sufficiently small. Moreover, by using the space-time weighted energy method initiated by Kawashima and Matsumura [2], the convergence rates (including the algebraic convergence rate and the exponential convergence rate) of u(t, x) toward φ(x) are also obtained in [1]. We note, however, that the analysis in [1] relies heavily on the assumption that f'(ub) 〈 0. The main purpose of this paper is devoted to discussing the case of f'(ub)= 0 and we show that similar results still hold for such a case. Our analysis is based on some delicate energy estimates.
基金supported by National Natural Science Foundation of China(Grant Nos.11201103 and 11471288)supported by the China Scholarship Council
文摘Instead of the L^p estimates,we study the modulation space estimates for the solution to the damped wave equation.Decay properties for both the linear and semilinear equations are obtained.The estimates in modulation space differ in many aspects from those in L^p space.
基金the Deanship of Scientific Research(DSR)at King Abdulaziz University,Jeddah,under grant No.(G:42-665-1442).
文摘A novel approximate analytical solution to the linear damped Kawahara equation using a suitable hypothesis is reported for the first time.Based on the exact solutions(such as solitary waves,cnoidal waves,etc.)of the undamped Kawahara equation,the dissipative nonlinear structures like dissipative solitons and cnoidal waves are investigated.The obtained solution is considered a general solution,i.e.,it can be applied for studying the properties of all dissipative traveling waves described by the linear damped Kawahara equation.Our technique is not limited to solve the linear damped Kawahara equation only,but it can be used for solving a large number of non-integrable evolution equations related to the realistic natural phenomena.Moreover,the maximum global residual error in the whole space-time domain is estimated for checking the accuracy of the obtained solutions.The obtained solutions can help many researchers in explaining the ambiguities about the mechanisms of propagation of nonlinear waves in complex systems such as seas,oceans,plasma physics,and much more.
文摘In this article,the main objective is to employ the homotopy perturbation method(HPM)as an alternative to classical perturbation methods for solving nonlinear equations having periodic coefficients.As a simple example,the nonlinear damping Mathieu equation has been investigated.In this investigation,two nonlinear solvability conditions are imposed.One of them was imposed in the first-order homotopy perturbation and used to study the stability behavior at resonance and non-resonance cases.The next level of the perturbation approaches another solvability condition and is applied to obtain the unknowns become clear in the solution for the firstorder solvability condition.The approach assumed here is so significant for solving many parametric nonlinear equations that arise within the engineering and nonlinear science.