In this paper, oscillatory properties of solutions of certain nonlinear hyperbolic partial differential equations are investigated and a series of sufficient conditions for oscillations of the equations are establishe...In this paper, oscillatory properties of solutions of certain nonlinear hyperbolic partial differential equations are investigated and a series of sufficient conditions for oscillations of the equations are established. The results fully indicate that the oscillations are caused by delay.展开更多
In order to improve the screening efficiency of vibrating screen and make vibration process smooth,a new type of magnetorheological (MR) damper was proposed. The signals of displacement in the vibration process during...In order to improve the screening efficiency of vibrating screen and make vibration process smooth,a new type of magnetorheological (MR) damper was proposed. The signals of displacement in the vibration process during the test were collected. The trispectrum model of autoregressive (AR) time series was built and the correlation dimension was used to quantify the fractal characteristics during the vibration process. The result shows that,in different working conditions,trispectrum slices are applied to obtaining the information of non-Gaussian,nonlinear amplitude?frequency characteristics of the signal. Besides,there is correlation between the correlation dimension of vibration signal and trispectrum slices,which is very important to select the optimum working parameters of the MR damper and vibrating screen. And in the experimental conditions,it is found that when the working current of MR damper is 2 A and the rotation speed of vibration motor is 800 r/min,the vibration screen reaches its maximum screening efficiency.展开更多
Some new sufficient conditions for the oscillation of the neutral equationddt[y(t)-R(t)y(t-r)]+P(t)y(t-τ)- Q(t)y(t-σ)=0, where P,Q,R∈C([t0,∞),R+) and r,τ,σ∈(0,∞),are obtained for the case whe...Some new sufficient conditions for the oscillation of the neutral equationddt[y(t)-R(t)y(t-r)]+P(t)y(t-τ)- Q(t)y(t-σ)=0, where P,Q,R∈C([t0,∞),R+) and r,τ,σ∈(0,∞),are obtained for the case where former results can not be applied in this paper.展开更多
Consider the second order nonlinear neutral delay differential equaiton[α(t)|(x(t)+p(t)x(t-τ))′| α-1 (x(t)+p(t)x(t-τ))′]′+q(t)|x(t-σ)| α-1 x(t-σ)=0. We obtain a sufficient condition for the oscillati...Consider the second order nonlinear neutral delay differential equaiton[α(t)|(x(t)+p(t)x(t-τ))′| α-1 (x(t)+p(t)x(t-τ))′]′+q(t)|x(t-σ)| α-1 x(t-σ)=0. We obtain a sufficient condition for the oscillation of all solutions of the above equation, our result extend and improve the result in .展开更多
In this paper, the sufficient conditions for the oscillation of all solutions of certain second order nonlinea neutral equations with continuous distributed delay.
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
We consider the nonlinear functional dynamic equation (p(t)[(r(t)x^△(t))^△]γ)^△+q(t)f(x(τ(t))) =0, for t≥t0,on a time scale T, where γ〉 0 is the quotient of odd positive integers, p, r, τ- ...We consider the nonlinear functional dynamic equation (p(t)[(r(t)x^△(t))^△]γ)^△+q(t)f(x(τ(t))) =0, for t≥t0,on a time scale T, where γ〉 0 is the quotient of odd positive integers, p, r, τ- and q are positive rd-continuous functions defined on the time scale 1F, and lirut→∞ τ(t) = ∞. The main aim of this paper is to establish some new sufficient conditions which guarantee that the equation has oscillatory solutions or the solutions tend to zero as →∞ τ. The main investigation depends on the Riccati substitution and the analysis of the associated Riccati dynamic inequality. Our results extend, complement and improve some previously obtained ones. In particular, the results provided substantial improvement for those obtained by Yu and Wang [J Comput Appl Math, 225 (2009), 531-540]. Some examples illustrating the main results are given.展开更多
文摘In this paper, oscillatory properties of solutions of certain nonlinear hyperbolic partial differential equations are investigated and a series of sufficient conditions for oscillations of the equations are established. The results fully indicate that the oscillations are caused by delay.
基金Project(50975098) supported by the National Natural Science Foundation of ChinaProject(2008HZ0002-1) supported by the Major Scientific and Technological Program of Fujian Province,China
文摘In order to improve the screening efficiency of vibrating screen and make vibration process smooth,a new type of magnetorheological (MR) damper was proposed. The signals of displacement in the vibration process during the test were collected. The trispectrum model of autoregressive (AR) time series was built and the correlation dimension was used to quantify the fractal characteristics during the vibration process. The result shows that,in different working conditions,trispectrum slices are applied to obtaining the information of non-Gaussian,nonlinear amplitude?frequency characteristics of the signal. Besides,there is correlation between the correlation dimension of vibration signal and trispectrum slices,which is very important to select the optimum working parameters of the MR damper and vibrating screen. And in the experimental conditions,it is found that when the working current of MR damper is 2 A and the rotation speed of vibration motor is 800 r/min,the vibration screen reaches its maximum screening efficiency.
文摘Some new sufficient conditions for the oscillation of the neutral equationddt[y(t)-R(t)y(t-r)]+P(t)y(t-τ)- Q(t)y(t-σ)=0, where P,Q,R∈C([t0,∞),R+) and r,τ,σ∈(0,∞),are obtained for the case where former results can not be applied in this paper.
文摘Consider the second order nonlinear neutral delay differential equaiton[α(t)|(x(t)+p(t)x(t-τ))′| α-1 (x(t)+p(t)x(t-τ))′]′+q(t)|x(t-σ)| α-1 x(t-σ)=0. We obtain a sufficient condition for the oscillation of all solutions of the above equation, our result extend and improve the result in .
文摘In this paper, the sufficient conditions for the oscillation of all solutions of certain second order nonlinea neutral equations with continuous distributed delay.
基金supported by National Key Basic Research Program of China (Grant No. 2013CB035604)National Natural Science Foundation of China (Grant Nos. 61034007, 51277116 and51107069)
文摘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.
基金supported by King Saud University,Dean-ship of Scientific Research,College of Science Research Centre
文摘We consider the nonlinear functional dynamic equation (p(t)[(r(t)x^△(t))^△]γ)^△+q(t)f(x(τ(t))) =0, for t≥t0,on a time scale T, where γ〉 0 is the quotient of odd positive integers, p, r, τ- and q are positive rd-continuous functions defined on the time scale 1F, and lirut→∞ τ(t) = ∞. The main aim of this paper is to establish some new sufficient conditions which guarantee that the equation has oscillatory solutions or the solutions tend to zero as →∞ τ. The main investigation depends on the Riccati substitution and the analysis of the associated Riccati dynamic inequality. Our results extend, complement and improve some previously obtained ones. In particular, the results provided substantial improvement for those obtained by Yu and Wang [J Comput Appl Math, 225 (2009), 531-540]. Some examples illustrating the main results are given.