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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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Desired Dynamic Equation for Primary Frequency Modulation Control of Gas Turbines
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作者 Aimin Gao Xiaobo Cui +2 位作者 Guoqiang Yu Jianjun Shu Tianhai Zhang 《Energy Engineering》 EI 2024年第5期1347-1361,共15页
Gas turbines play core roles in clean energy supply and the construction of comprehensive energy systems.The control performance of primary frequency modulation of gas turbines has a great impact on the frequency cont... Gas turbines play core roles in clean energy supply and the construction of comprehensive energy systems.The control performance of primary frequency modulation of gas turbines has a great impact on the frequency control of the power grid.However,there are some control difficulties in the primary frequency modulation control of gas turbines,such as the coupling effect of the fuel control loop and speed control loop,slow tracking speed,and so on.To relieve the abovementioned difficulties,a control strategy based on the desired dynamic equation proportional integral(DDE-PI)is proposed in this paper.Based on the parameter stability region,a parameter tuning procedure is summarized.Simulation is carried out to address the ease of use and simplicity of the proposed tuning method.Finally,DDE-PI is applied to the primary frequency modulation system of an MS6001B heavy-duty gas turbine.The simulation results indicate that the gas turbine with the proposed strategy can obtain the best control performance with a strong ability to deal with system uncertainties.The proposed method shows good engineering application potential. 展开更多
关键词 Gas turbine primary frequency modulation(PFM) desired dynamic equation(DDE) proportion-integral(PI)
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SOME OSCILLATION CRITERIA FOR A CLASS OF HIGHER ORDER NONLINEAR DYNAMIC EQUATIONS WITH A DELAY ARGUMENT ON TIME SCALES 被引量:1
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作者 Xin WU 《Acta Mathematica Scientia》 SCIE CSCD 2021年第5期1474-1492,共19页
In this paper,we establish some oscillation criteria for higher order nonlinear delay dynamic equations of the form[rnφ(⋯r2(r1x^(Δ))^(Δ)⋯)^(Δ)]^(Δ)(t)+h(t)f(x(τ(t)))=0 on an arbitrary time scale T with supT=∞,w... In this paper,we establish some oscillation criteria for higher order nonlinear delay dynamic equations of the form[rnφ(⋯r2(r1x^(Δ))^(Δ)⋯)^(Δ)]^(Δ)(t)+h(t)f(x(τ(t)))=0 on an arbitrary time scale T with supT=∞,where n≥2,φ(u)=|u|^(γ)sgn(u)forγ>0,ri(1≤i≤n)are positive rd-continuous functions and h∈C_(rd)(T,(0,∞)).The functionτ∈C_(rd)(T,T)satisfiesτ(t)≤t and lim_(t→∞)τ(t)=∞and f∈C(R,R).By using a generalized Riccati transformation,we give sufficient conditions under which every solution of this equation is either oscillatory or tends to zero.The obtained results are new for the corresponding higher order differential equations and difference equations.In the end,some applications and examples are provided to illustrate the importance of the main results. 展开更多
关键词 OSCILLATION nonlinear dynamic equations higher order equation delay dynamic equations time scale
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Oscillation of Second-order Nonlinear Dynamic Equation on Time Scales 被引量:7
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作者 YANG Jia-shan 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第2期172-179,共8页
: The oscillation for a class of second order nonlinear variable delay dynamic equation on time scales with nonlinear neutral term and damping term was discussed in this article. By using the generalized Riccati tech... : The oscillation for a class of second order nonlinear variable delay dynamic equation on time scales with nonlinear neutral term and damping term was discussed in this article. By using the generalized Riccati technique, integral averaging technique and the time scales theory, some new sufficient conditions for oscillation of the equation are proposed. These results generalize and extend many knownresults for second order dynamic equations. Some examples are given to illustrate the main results of this article. 展开更多
关键词 time scales dynamic equations nonlinear neutral term damping term variable delay Riccati transformation OSCILLATION
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Solution of general dynamic equation for nanoparticles in turbulent flow considering fluctuating coagulation 被引量:4
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作者 Jianzhong LIN Xiao jun PAN +1 位作者 Zhaoqin YIN Xiaoke KU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第10期1275-1288,共14页
A new averaged general dynamic equation (GDE) for nanoparticles in the turbulent flow is derived by considering the combined effect of convection, Brownian diffusion, turbulent diffusion, turbulent coagulation, and ... A new averaged general dynamic equation (GDE) for nanoparticles in the turbulent flow is derived by considering the combined effect of convection, Brownian diffusion, turbulent diffusion, turbulent coagulation, and fluctuating coagulation. The equation is solved with the Taylor-series expansion moment method in a turbulent pipe flow. The experiments are performed. The numerical results of particle size distribu- tion correlate well with the experimental data. The results show that, for a turbulent nanoparticulate flow, a fluctuating coagulation term should be included in the averaged particle GDE. The larger the Schmidt number is and the lower the Reynolds number is, the smaller the value of ratio of particle diameter at the outlet to that at the inlet is. At the outlet, the particle number concentration increases from the near-wall region to the near-center region. The larger the Schmidt number is and the higher the Reynolds num- ber is, the larger the difference in particle number concentration between the near-wall region and near-center region is. Particle polydispersity increases from the near-center region to the near-wall region. The particles with a smaller Schmidt number and the flow with a higher Reynolds number show a higher polydispersity. The degree of particle polydispersity is higher considering fluctuating coagulation than that without considering fluctuating coagulation. 展开更多
关键词 NANOPARTICLE general dynamic equation (GDE) fluctuating coagulation term particle distribution turbulent pipe flow
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INVESTIGATION ON KANE DYNAMIC EQUATIONSBASED ON SCREW THEORY FOR OPEN-CHAIN MANIPULATORS 被引量:3
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作者 刘武发 龚振邦 汪勤悫 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第5期627-635,共9页
First,screw theory,product of exponential formulas and Jacobian matrix are introduced.Then definitions are given about active force wrench,inertial force wrench,partial velocity twist,generalized active force,and gene... First,screw theory,product of exponential formulas and Jacobian matrix are introduced.Then definitions are given about active force wrench,inertial force wrench,partial velocity twist,generalized active force,and generalized inertial force according to screw theory.After that Kane dynamic equations based on screw theory for open-chain manipulators have been derived. Later on how to compute the partial velocity twist by geometrical method is illustrated. Finally the correctness of conclusions is verified by example. 展开更多
关键词 screw theory partial velocity twist open-chain manipulator Kane dynamic equation
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OSCILLATION CRITERIA FOR SECOND ORDER NONLINEAR DYNAMIC EQUATIONS WITH p-LAPLACIAN AND DAMPING 被引量:2
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作者 Taher S.HASSAN Qingkai KONG 《Acta Mathematica Scientia》 SCIE CSCD 2013年第4期975-988,共14页
This paper concerns the oscillation of solutions of the second order nonlinear dynamic equation with p-Laplacian and damping(r(t)φ(x^△(t))^△+p(t)φα(x^△α(t)+q(t)f(xδ(t))=0on a time scale T w... This paper concerns the oscillation of solutions of the second order nonlinear dynamic equation with p-Laplacian and damping(r(t)φ(x^△(t))^△+p(t)φα(x^△α(t)+q(t)f(xδ(t))=0on a time scale T which is unbounded above. Sign changes are allowed for the coefficient functions r, p and q. Several examples are given to illustrate the main results. 展开更多
关键词 OSCILLATION dynamic equations time scales
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Hyers-Ulam Stability of First Order Nonhomogeneous Linear Dynamic Equations on Time Scales 被引量:1
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作者 Shen Yong-hong Li Yong-jin Li Yong 《Communications in Mathematical Research》 CSCD 2019年第2期139-148,共10页
This paper deals with the Hyers-Ulam stability of the nonhomogeneous linear dynamic equation x~?(t)-ax(t) = f(t), where a ∈ R^+. The main results can be regarded as a supplement of the stability results of the corres... This paper deals with the Hyers-Ulam stability of the nonhomogeneous linear dynamic equation x~?(t)-ax(t) = f(t), where a ∈ R^+. The main results can be regarded as a supplement of the stability results of the corresponding homogeneous linear dynamic equation obtained by Anderson and Onitsuka(Anderson D R, Onitsuka M. Hyers-Ulam stability of first-order homogeneous linear dynamic equations on time scales. Demonstratio Math., 2018, 51: 198–210). 展开更多
关键词 Hyers-Ulam stability ■-derivative time scale linear dynamic equation
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New Oscillation Criteria for Second Order Half-Linear Neutral Type Dynamic Equations on Time Scales 被引量:1
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作者 Faisal Al-Dheleai Elmetwally Elabbasy 《Journal of Applied Mathematics and Physics》 2021年第9期2376-2398,共23页
In this paper, we will study the oscillatory properties of the second order half-linear dynamic equations with distributed deviating arguments on time scales. We obtain several new sufficient conditions for the oscill... In this paper, we will study the oscillatory properties of the second order half-linear dynamic equations with distributed deviating arguments on time scales. We obtain several new sufficient conditions for the oscillation of all solutions of this equation. Our results not only unify the oscillation of second order nonlinear differential and difference equations but also can be applied to different types of time scales with sup T = ∞. Our results improve and extend some known results in the literature. Examples which dwell upon the importance of our results are also included. 展开更多
关键词 dynamic equation Oscillatory Solutions NEUTRAL Deviating Arguments
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COORDINATION OF THE MOTION PARAMETERS WITHIN STEP-BY-STEP INTEGRATION FOR DYNAMIC EQUATION
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作者 HuangQingfeng WangQuanfeng HuYunchang 《Acta Mechanica Solida Sinica》 SCIE EI 2004年第1期27-31,共5页
A method is presented that coordinates the calculation of the displacement, velocity and acceleration of structures within the time-steps of different types of step-by-step integration. The dynamic equation is solved ... A method is presented that coordinates the calculation of the displacement, velocity and acceleration of structures within the time-steps of different types of step-by-step integration. The dynamic equation is solved using an energy equation and the calculating data of the original method. The method presented is better than the original method in terms of calculating postulations and is in better conformity with the system's movement. Take the Wilson-θ method as an example. By using the coordination process, the calculation precision has been greatly im proved (reducing the errors by approximately 90% ), and the greater part of overshooting of the calculation result has been eliminated. The study suggests that the mal-coordination of the motion parameters within the time-step is the major factor that contributes to the result errors of step-by-step integration for the dynamic equation. 展开更多
关键词 step-by-step integration motion parameters COORDINATION dynamic equation en- ergy equation
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Research and Application of Dynamic Equation for Full Frontal Impact
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作者 Sheng Tian 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第3期101-106,共6页
Full frontal impact theory needs researching and exploring to satisfy the primary safety design of occupant restraint system,avoiding the increasingly "engineering"trend in order to develop and design safety... Full frontal impact theory needs researching and exploring to satisfy the primary safety design of occupant restraint system,avoiding the increasingly "engineering"trend in order to develop and design safety vehicle. After occupant restraint system is simulated by using linear elastic stiffness k,the occupant-vehicle frontal rigid barrier impact model is established. Dynamic equation of dummy chest coupling vehicle is built for full frontal impact based on ordinary vehicle deceleration by Hooke law,and the equation is solved by comparing coefficient and satisfying boundary qualifications. While relative vehicle characteristic parameters are kept unchanging,the actual vehicle deceleration is fitted to the simplified equivalent square wave( ESW),tipped equivalent square wave( TESW) and equivalent dual trapezoids wave( EDTW). Phase angle  and amplitude A of dynamic equations based on ESW,TESW and EDTW are calculated and deduced. The results show that: the dynamic equation of dummy chest coupling vehicle can be well utilized to instruct the primary safety design of full frontal impact for objective vehicle to satisfy chest deceleration demands and the equation based on TESW is best for this design. 展开更多
关键词 vehicle engineering full frontal impact dynamic equation DECELERATION simplified wave occupant restraint system
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POSITIVE SOLUTIONS FOR p-LAPLACIAN DYNAMIC EQUATIONS ON TIME SCALES
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作者 Geng Fengjie Zhu Deming Li Hongzhi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2007年第1期69-77,共9页
The three-point boundary value problems of p-Laplacian dynamic equations on time scales are investigated. By using Krasnosel'skii's fixed-point theorem and fixed-point index theorem, criteria are achieved for the ex... The three-point boundary value problems of p-Laplacian dynamic equations on time scales are investigated. By using Krasnosel'skii's fixed-point theorem and fixed-point index theorem, criteria are achieved for the existence of at least one, two or 2n positive solutions. Furthermore, some examples are included to illustrate the main theorems. 展开更多
关键词 time scale jump operator three-point boundary value problem dynamic equation cone.
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Dynamic equations for curved submerged floating tunnel
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作者 董满生 葛斐 +1 位作者 张双寅 洪友士 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第10期1299-1308,共10页
In virtue of reference Cartesian coordinates, geometrical relations of spatial curved structure are presented in orthogonal curvilinear coordinates. Dynamic equations for helical girder are derived by Hamilton princip... In virtue of reference Cartesian coordinates, geometrical relations of spatial curved structure are presented in orthogonal curvilinear coordinates. Dynamic equations for helical girder are derived by Hamilton principle. These equations indicate that four generalized displacements are coupled with each other. When spatial structure degenerates into planar curvilinear structure, two generalized displacements in two perpendicular planes are coupled with each other. Dynamic equations for arbitrary curvilinear structure may be obtained by the method used in this paper. 展开更多
关键词 submerged floating tunnel (SFT) dynamic equations Hamilton principle curved girder
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The General Solution and Ulam Stability of Second Order Linear Dynamic Equations on Time Scales
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作者 Yonghong SHEN Yongjin LI 《Journal of Mathematical Research with Applications》 CSCD 2020年第5期493-506,共14页
By using the variation of parameters, this paper deals with the general solution and Ulam stability of second order linear dynamic equations with variable coefficients on time scales.In particular, we also obtain the ... By using the variation of parameters, this paper deals with the general solution and Ulam stability of second order linear dynamic equations with variable coefficients on time scales.In particular, we also obtain the Ulam stability of second order linear dynamic equations with constant coefficients under different cases. 展开更多
关键词 Ulam stability second order linear dynamic equations time scales
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GENERAL DYNAMIC EQUATION AND DYNAMICAL CHARACTERISTICS OF VISCOELASTIC TIMOSHENKO BEAMS
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作者 肖灿章 计伊周 常保平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第2期177-184,共8页
In this paper, a governing differential equation of viscoelastic Timoshenko beam including both extension and shear viscosity is developed in the time domain by direct method. To measure the complex moduli and three p... In this paper, a governing differential equation of viscoelastic Timoshenko beam including both extension and shear viscosity is developed in the time domain by direct method. To measure the complex moduli and three parameters of standard linear solid, the forced vibration technique of beam is successfully used for PCL and PMMA specimens. The dynamical characteristics of viscoelastic Timoshenko beams, especially the damping properties, are derived from a considerable number of numerical computations. The analyses show that the viscosity of materials has great influence on dynamical characteristics of structures, especially on damping, and the standard linear solid model is the better one for describing the dynamic behavior of high viscous materials. 展开更多
关键词 GENERAL dynamic equation AND dynamicAL CHARACTERISTICS OF VISCOELASTIC TIMOSHENKO BEAMS
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Smolyak Type Sparse Grid Collocation Method for Uncertainty Quantification of Nonlinear Stochastic Dynamic Equations
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作者 石红芹 何军 《Journal of Shanghai Jiaotong university(Science)》 EI 2015年第5期612-617,共6页
This paper develops a Smolyak-type sparse-grid stochastic collocation method(SGSCM) for uncertainty quantification of nonlinear stochastic dynamic equations.The solution obtained by the method is a linear combination ... This paper develops a Smolyak-type sparse-grid stochastic collocation method(SGSCM) for uncertainty quantification of nonlinear stochastic dynamic equations.The solution obtained by the method is a linear combination of tensor product formulas for multivariate polynomial interpolation.By choosing the collocation point sets to coincide with cubature point sets of quadrature rules,we derive quadrature formulas to estimate the expectations of the solution.The method does not suffer from the curse of dimensionality in the sense that the computational cost does not increase exponentially with the number of input random variables.Numerical analysis of a nonlinear elastic oscillator subjected to a discretized band-limited white noise process demonstrates the computational efficiency and accuracy of the developed method. 展开更多
关键词 sparse grid Smolyak algorithm stochastic dynamic equation uncertainty quantification
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On the Oscillation of Second-Order Nonlinear Neutral Delay Dynamic Equations on Time Scales
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作者 Quanxin Zhang Xia Song Li Gao 《Journal of Applied Mathematics and Physics》 2016年第6期1080-1089,共10页
Based on Riccati transformation and the inequality technique, we establish some new sufficient conditions for oscillation of the second-order neutral delay dynamic equations on time scales. Our results not only extend... Based on Riccati transformation and the inequality technique, we establish some new sufficient conditions for oscillation of the second-order neutral delay dynamic equations on time scales. Our results not only extend and improve some known theorems, but also unify the oscillation of the second-order nonlinear delay differential equation and the second-order nonlinear delay difference equation on time scales. At the end of this paper, we give an example to illustrate the main results. 展开更多
关键词 OSCILLATION dynamic equations NEUTRAL Time Scale
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Kamenev-type criteria for nonlinear damped dynamic equations 被引量:13
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作者 BOHNER Martin LI TongXing 《Science China Mathematics》 SCIE CSCD 2015年第7期1445-1452,共8页
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
关键词 OSCILLATION second-order dynamic equation nonlinear damped delay equation time scale
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Oscillation of fourth-order delay dynamic equations 被引量:7
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作者 ZHANG Cheng Hui AGARWAL Ravi P. +1 位作者 BOHNER Martin LI Tong Xing 《Science China Mathematics》 SCIE CSCD 2015年第1期143-160,共18页
This paper is concerned with oscillatory behavior of a class of fourth-order delay dynamic equations on a time scale.In the general time scales case,four oscillation theorems are presented that can be used in cases wh... This paper is concerned with oscillatory behavior of a class of fourth-order delay dynamic equations on a time scale.In the general time scales case,four oscillation theorems are presented that can be used in cases where known results fail to apply.The results obtained can be applied to an equation which is referred to as Swift-Hohenberg delay equation on a time scale.These criteria improve a number of related contributions to the subject.Some illustrative examples are provided. 展开更多
关键词 Swift-Hohenberg equation OSCILLATION delay dynamic equation FOURTH-ORDER time scale
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Oscillation of Third-order Delay Dynamic Equations on Time Scales 被引量:6
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作者 YANG Jia-shan 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第3期447-456,共10页
This paper is concerned with the oscillatory behavior of a class of third-order noonlinear variable delay neutral functional dynamic equations on time scale. By using the generalized Riccati transformation and inequal... This paper is concerned with the oscillatory behavior of a class of third-order noonlinear variable delay neutral functional dynamic equations on time scale. By using the generalized Riccati transformation and inequality technique, we establish some new oscilla- tion criteria for the equations. Our results extend and improve some known results, but also unify the oscillation of third-order nonlinear variable delay functional differential equations and functional difference equations with a nonlinear neutral term. Some examples are given to illustrate the importance of our results. 展开更多
关键词 OSCILLATION time scales delay dynamic equations l^iccati transformation non-linear neutral term
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