Oscillation criterion for half-linear differential equations with periodic coefficients

In this paper, we present an oscillation criterion for second order half-linear differential equations with periodic coefficients. The method is based on the nonexistence of a proper solution of the related modified Riccati equation. Our result can be regarded as an oscillatory counterpart to the nonoscillation criterion by Sugie and Matsumura (2008). These two theorems provide a complete half-linear extension of the oscillation criterion of Kwong and Wong (2003) dealing with the Hill’s equation.     

时间尺度上具阻尼项的二阶半线性时滞动力方程的振动准则

利用广义Riccati变换和不等式技巧,研究了一类具阻尼项的二阶半线性时滞动力方程解的振动性质,在一定条件下,建立了四个新的振动准则,其结果不仅推广和改进了已知的一些结果,而且在时间尺度上统一了具阻尼项的二阶半线性时滞微分方程和差分方程解的振动性质.     

Oscillation of second-order half-linear delay dynamic equations with damping on time scales

By using the generalized Riccati transformation and the inequality technique, we establish a few new oscillation criterions for certain second-order half-linear delay dynamic equations with damping on a time scale. Our results extend and improve some known results, but also unify the oscillation of the second-order half-linear delay differential equation with damping and the second-order half-linear delay difference equation with damping.     

Linearization of second-order superlinear oscillation theorems

In this paper, for second-order superlinear differential equations, we present new oscillation criteria. Our results involve comparison with related linear and half-linear second-order differential equations, so that the known oscillation theorems from literature can be employed directly.     

Forced oscillation criteria for superlinear-sublinear elliptic equations via Picone-type inequality

Picone-type inequality is derived for a class of superlinear-sublinear elliptic equations with a forcing term, and oscillation results are established by utilizing the Picone-type inequality. Our approach is to reduce the multi-dimensional oscillation problems to one-dimensional oscillation problems for half-linear ordinary differential equations.     

一类二阶半线性泛函微分方程的振动性

研究二阶半线性中立型分布时滞微分方程,利用Riccati变换,积分平均和不等式技巧,得到了一切解均为振动的若干新的振动准则,推广和改进了最近文献中的一些结果.     

A remark on connection between conjugacy of half-linear differential equation and equation with mixed nonlinearities

In this paper new criteria for conjugacy of half-linear ordinary differential equations are derived by using a Riccati transformation. These criteria are used to derive nonexistence and oscillation results for an equation with mixed nonlinearities, which is viewed as a perturbation of a half-linear equation.     

Comparison theorems for oscillation of second-order half-linear differential equations

Summary We establish new comparison theorems on the oscillation of solutions of a class of perturbed half-linear differential equations. These improve the work of Elbert and Schneider [6] in which connections are found between half-linear differential equations and linear differential equations. Our comparison theorems are not of Sturm type or Hille--Wintner type which are very famous. We can apply the main results in combination with Sturm's or Hille--Wintner's comparison theorem to a half-linear differential equation of the general form (|x'|^α-1x')' + a(t) |x|^α-1x = 0.     

二阶半线性微分方程的振动定理

我们建立了二阶半线性微分方程(1)的新的振动定理,推广了Leighton和Kamenev的某些结果.     

Variational technique and principal solution in half-linear oscillation criteria

We investigate oscillatory properties of half-linear differential equations. The investigated half-linear equation is viewed as a perturbation of another (nonoscillatory) equation of the same form and perturbation is allowed both in the absolute term and in the derivative term. First, the Sturmian type theorem for solutions of the associated Riccati equation is established. In the second part of the paper we prove new half-linear oscillation criteria using the variational technique.     

Oscillation criteria for even-order half-linear functional differential equations with damping

In this paper, a class of even-order half-linear functional differential equations with damping are studied. By using the generalized Riccati transformation and the integral averaging technique, new oscillation criteria are obtained for all solutions of the equations, which generalize and improve some known results.     

Integral condition for oscillation of half-linear differential equations with damping

The purpose of this paper is to provide an oscillation theorem that can be applied to half-linear differential equations with time-varying coefficients. A parametric curve by the coefficients is focused in order to obtain our theorem. This parametric curve is a generalization of the curve given by the characteristic equation of the second-order linear differential equation with constant coefficients. The obtained theorem is proved by transforming the half-linear differential equation to a standard polar coordinates system and using phase plane analysis carefully.     

New results for oscillatory behavior of even-order half-linear delay differential equations

Some new oscillation results are presented that improve those reported in [C. Zhang, T. Li, B. Sun, and E. Thandapani, On the oscillation of higher-order half-linear delay differential equations, Appl. Math. Lett. 24 (2011) 1618–1621].     

偶阶半线性阻尼泛函微分方程的振动性

本文讨论了偶阶半线性阻尼泛函微分方程解的振动性质.利用广义Riccati变换和不等式技巧得到了所述方程的一切解均为振动的若干新的振动准则,推广和改进了一些文献中的结果.     

An oscillation criterion for forced half-linear differential equations with mixed nonlinearities

In this note, a new oscillation criterion for forced half-linear second order differential equations with mixed nonlinearities is obtained by using a generalized Riccati transformation. The result of this note generalizes and improves some previous results in the literature.     

偶阶半线性中立型分布时滞微分方程的振动性

摘要本文研究偶阶半线性中立型分布时滞微分方程,利用广义Riccati变换和积分平均技巧得到方程一切解均为振动的若干新的振动准则,推广和改进了一些文献中的结果.     

Sharp oscillation criteria for second-order neutral delay differential equations

This paper is a continuation of a recent work by the authors on the oscillatory properties of second-order half-linear neutral delay differential equations. Providing a new apriori bound for a nonoscillatory solution, we present a new oscillation criterion, which essentially improves the existing ones. In a particular nonneutral case, the obtained oscillation constant is unimprovable.     

Nonoscillation and oscillation of second-order impulsive differential equations with periodic coefficients

In this paper, we give a nonoscillation criterion for half-linear equations with periodic coefficients under fixed moments of impulse actions. The method is based on the existence of positive solutions of the related Riccati equation and a recently obtained comparison principle. In the special case when the equation becomes impulsive Hill equation new oscillation criteria are also obtained.     

Oscillation of the half-linear PDE in general exterior domains—the variational approach

In the paper a variational technique is used to show how to derive new oscillation criteria for the half-linear partial differential equation via the oscillation criteria for the ordinary half-linear differential equation. In contrast to the results usually found in the literature, general types of unbounded domains can be considered.     

An oscillation criterion for nonhomogeneous half-linear differential equations

By means of a classical inequality and an averaging technique, we obtain an oscillation criterion for nonhomogeneous half-linear differential equations. Our result is much more general than a recent result of Wong [1] and makes use of the oscillatory behavior of the forcing terms on intervals.