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61.
Bao Tong Cui Maoan Han Huizhong Yang 《Journal of Computational and Applied Mathematics》2005,180(2):365-375
This paper deals with the oscillation problems of delay hyperbolic systems with impulses. Some sufficient conditions for oscillations of impulsive delay hyperbolic systems with Robin boundary conditions are obtained and the criteria of oscillation of the systems are established. 相似文献
62.
QiGuiYANG 《数学学报(英文版)》2005,21(1):17-30
By using the Riccati technique and the technique, new oscillation criteria are obtained for the second order matrix differential system(P(t)Y′(t))′ r(t)P(t)Y′(t) Q(t)Y(t) = 0, t≥t0.These results in the present paper generalize and improve many known conclusions. Furthermore, some results are different from the most known ones in the sense that they are based on the information only on a sequence of subintervals of [t0, ∞), rather than on the whole half-line. In particular, our results complement a number of existing results and handle the ease that is not covered by the known criteria. 相似文献
63.
This communication gives the corrigendum to the paper “Oscillation criteria for first-order impulsive differential equations with positive and negative coefficients” (JCAM (2007), doi:10.1016/j.cam.2007.06.016). 相似文献
64.
Using a generalization of Sturm’s comparison theorem, some new oscillation criteria are established for the matrix differential system with damping
under the hypothesis: P(t)=P∗(t)>0, Q(t)=Q∗(t), Y(t) are n×n matrices of real valued continuous functions on the interval [t0,∞), and R(t)=R∗(t)∈C1([t0,∞),Rn2). Our results are sharper than some previous results. 相似文献
(P(t)Y′)′+R(t)Y′+Q(t)Y=0
65.
The authors discuss the relation of the oscillation of the following two difference equations, where m ≥ 2, τ : N → N, N isthe set of integers, |n − τ(n)| ≤ Mfor n N0, M is a positive integer, is nondecreasing in x, xf(n, x)> 0, as x ≠ 0. Wewill show some relations of the oscillation of the above two equations. Especially, for m to be even, we establish the equivalenceof the oscillation of the above two difference equations. 相似文献
66.
New Kamenev-type oscillation criteria for second-order nonlinear differential equations with damping 总被引:1,自引:0,他引:1
Yuan Gong Sun 《Journal of Mathematical Analysis and Applications》2004,291(1):341-351
Some new oscillation criteria are established for the nonlinear damped differential equation (r(t)y′)′+p(t)y′+q(t)f(y)=0 that are different from most known ones in the sense that they are based on a class of new functions Φ(t,s,r) defined in the sequel. Our results are sharper than some previous results which can be seen by the examples at the end of this paper. 相似文献
67.
Wan-Tong Li 《Applied Mathematics Letters》1997,10(6):101-106
Consider the first-order neutral nonlinear difference equation of the form , where τ > 0, σi ≥ 0 (i = 1, 2,…, m) are integers, {pn} and {qn} are nonnegative sequences. We obtain new criteria for the oscillation of the above equation without the restrictions Σn=0∞ qn = ∞ or Σn=0∞ nqn Σj=n∞ qj = ∞ commonly used in the literature. 相似文献
68.
具有偏差变元的双曲型微分方程组解的振动性 总被引:65,自引:0,他引:65
本文获得了双曲型方程组在齐次Neumann,Dirichlet和Robin边值条件下,所有解振动的充分条件. 相似文献
69.
建立了非线性差分方程所有正解关于其正平衡点振动的充要条件,部分地解决了文[1]中的一个公开问题,同时还获得了方程的正平衡点渐近稳定的一个充分性判据. 相似文献
70.
A class of nonlinear coupled system for El Nino-Southern Oscillation(ENSO) model is considered.Using the asymptotic theory and method of variational iteration,the asymptotic expansion of the solution for ENSO models is obtained. 相似文献