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1.
In this paper, some sufficient and necessary conditions are established for the oscillatory of solutions for nonlinear functional difference equations, which extend and improve some corresponding results obtained and are discrete analogues of the corresponding results for the continuous version.  相似文献   

2.
Fixed point and common fixed point results for mappings satisfying quasi-contractive conditions expressed in the terms of c-distance on TVS-valued cone met-ric spaces (without the underlying cone which is not normal) are obtained, and P-property and Q-property for mappings in the terms of c-distance are discussed. Our results generalize and improve many known results.  相似文献   

3.
Characterization theorems for abundant sernigroups having a quasi-ideal quasi-adequate transversal are obtained. Our results generalize and amplify the related results of Satio on regular semigroup obtained in 1985 and Kong obtained in 2007 respectively. Some recent results on this topic given by Guo-Shum are strengthened. In particular, the structure of such an abundant semigroup is described.  相似文献   

4.
Using the integral average technique and a new function,some new oscillation criteria related to Euler integral are obtained for second order nonlinear differential equations with damping and forcing. Our results are of a higher degree of generality than some previous results. Information about the distribution of the zeros of solutions to the system is also obtained.  相似文献   

5.
ON PERIODIC DYNAMICAL SYSTEMS   总被引:5,自引:0,他引:5       下载免费PDF全文
The authors investigate the existence and the global stability of periodic solution for dynamical systems with periodic interconnections, inputs and self-inhibitions. The model is very general, the conditions are quite weak and the results obtained are universal.  相似文献   

6.
In this paper, the authors show some monotonicity and concavity of the classical psi function, by which several known results are improved and some new asymptotically sharp estimates are obtained for this function. In addition, applying the new results to the psi function,the authors improve the well-known lower and upper bounds for the approximate evaluation of Euler's constant γ.  相似文献   

7.
In this paper, we study a bounded-below singular Hamiltonian system. Sufficient and necessary conditions are obtained for the existence and the number of eigenvalues on the left-axis. The main results of this paper are the extension and improvement of Weyl spectral theorem for singular second order differential equations.  相似文献   

8.
In this paper,the complete convergence and complete moment convergence for maximal weighted sums of extended negatively dependent random variables are investigated.Some sufficient conditions for the convergence are provided.In addition,the Marcinkiewicz–Zygmund type strong law of large numbers for weighted sums of extended negatively dependent random variables is obtained.The results obtained in the article extend the corresponding ones for independent random variables and some dependent random variables.  相似文献   

9.
This paper studies the global and local properties of the trajectories of Gaussian random fields with stationary increments and proves sufficient conditions for Strassen's functional laws of the iterated logarithm at zero and infinity respectively.The sets of limit points of those Gaussian random fields are obtained.The main results are applied to fractional Riesz-Bessel processes and the sets of limit points of this field are obtained.  相似文献   

10.
We establish Berry-Esseen bounds and Cramér type large deviations for the eigenvalues of Wigner Hermitian matrices in the bulk and at the edge cases. Similar results are also obtained for covariance matrices.  相似文献   

11.
刘易成  李志祥 《数学学报》2006,49(5):1067-107
本文获得了几个压缩型映射的不动点定理,改进了相应文献的结果.应用该定理,给出了一类时滞积分方程的正概周期解的存在性结果.推广了已有的结果.  相似文献   

12.
Existence and uniqueness results for three-point boundary value problems for the third order nonlinear differential equations are obtained. The results are better than those obtained recently by Barr and Sherman, using extra conditions.  相似文献   

13.
独立与NA列部分和的精致渐近性   总被引:8,自引:2,他引:6  
成凤旸  王岳宝 《数学学报》2004,47(5):965-972
令{X,Xi:i≥1)为属于非退化稳定分布一般吸引场的独立同分布随机变量列,Sn=∑i=1nXi.本文对十分广泛的拟权函数和边界函数得到了Sn的精致渐近的结果和正态吸引场强平稳NA列部分和的精致渐近的结果,改进并推广了Wang等的结果,从而使此前关于独立列和NA列部分和精致渐近性方面的许多经典的和最新的结果都可以包括在本文的框架之内.  相似文献   

14.
研究了一类具有多个时滞的二阶非线性差分方程,利用数学归纳法和Lebesgue控制收敛定理得出了其有界解振动的充分必要条件及其任一解与解的差分振动的充分条件,所得结果包含和推广了已有的结果.  相似文献   

15.
In this paper the influence of the gravity field, relaxation times and initial stress on propagation of Rayleigh waves in an orthotropic magneto-thermoelastic solid medium has been investigated. The solution of the more general equations are obtained for thermoelastic coupling by Helmoltz’s theorem. The frequency equation which determines Rayleigh wave velocity have been obtained. Many special cases are investigated from the present problem. Numerical results analyzing the frequency equation are obtained and presented graphically. Relevant results of previous investigations are deduced as special cases from these results. The results indicate that the effect of initial stress, magnetic field and gravity field are very pronounced.  相似文献   

16.
We present some results for the global attractivity of solutions for fractional differential equations involving Riemann-Liouville fractional calculus. The results are obtained by employing Krasnoselskii’s fixed point theorem. Similar results for fractional differential equations involving Caputo fractional derivative are also obtained by using the classical Schauder’s fixed point theorem. Several examples are given to illustrate our main results.  相似文献   

17.
《代数通讯》2013,41(4):1513-1550
In this paper we study closed sub-bimodules of normalizing bimodules over semiprime rings. We extend the main results which are known for centred bimodules and several other results which are new even for centred bimodules are also obtained. In particular, we prove that the theorem on one-to-one correspondence between closed submodules obtained in former papers for centred bimodules is also true for normalizing bimodules. Finally, we give some applications of the main results.

  相似文献   

18.
Solutions for a class of nonlinear second-order differential equations, arising in diffusion of chemically reactive species of a non-Newtonian fluid immersed in a porous medium over a stretching sheet, are obtained. Furthermore, using the Brouwer fixed point theorem, existence results are established. Moreover, the exact analytical solutions (for some special cases) are obtained. The results obtained for the diffusion characteristics reveal many interesting behaviors that warrant further study of the effects of reaction rate on the transfer of chemically reactive species.  相似文献   

19.
徐西安 《应用数学》2006,19(3):606-612
本文首先使用拓扑度和不动点指数方法,得到了关于抽象空间中算子方程变号解及多个变号解存在的几个结果,然后将所得结果应用于一类含脉冲三点边值问题,得到了变号解及多个变号解的存在性结果.  相似文献   

20.
Strong differential subordination and superordination results are obtained for analytic functions in the open unit disk by investigating appropriate classes of admissible functions. New strong differential sandwich-type results are also obtained.  相似文献   

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