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991.
根据Cauchy微分中值定理表达式的结构引入辅助函数 F(x ,c)= f (x)- f (c)g(x)- g(c)(a< c< b),通过讨论其可导性,得到相关的几个不等式,由此得出Cauchy微分中值定理存在唯一“中值点”的一个条件,并给出其逆定理的一个较弱表述。 相似文献
992.
In this paper, sufficient conditions have been obtained for oscillation/nonoscillation of a class of homogeneous/nonhomogeneous linear difference equations of third order. 相似文献
993.
In this research, we study linear difference equations with constant coefficients subject to boundary conditions. Necessary and/or sufficient conditions for the existence of a unique solution will be established. The proofs of the existence and uniqueness theorems are established by means of special types of determinants called Mosaic Vandermonde determinants. 相似文献
994.
Chuanxi Qian 《Journal of Difference Equations and Applications》2013,19(2):163-175
In this paper, we establish a sufficient condition for every solution of the forced difference equation $$x_{n+1} - x_n + p_nx_{n-k} = r_n, \ \ n=0, 1, \ldots$$ 相似文献
995.
In this paper we study the solvability of nonlinear, discrete-time boundary value problems for functional equations. Conditions are established for the existence of solutions to problems of the form $$x(k + 1) = f(k, x(k)) + \lambda g(k, x(k)); \quad k = 0, 1, 2, \ldots$$ 相似文献
996.
C. Bereanu 《Journal of Difference Equations and Applications》2013,19(7):677-695
We use Brouwer degree to prove existence and multiplicity results for the periodic solutions of some nonlinear second-order and first-order difference equations. We obtain, in particular upper and lower solutions theorems, Ambrosetti–Prodi type results and sharp existence conditions for nonlinearities which are bounded from below or above. 相似文献
997.
We formally derive and rigorously justify the modulation equations of lowest order for the interaction of two modulated pulses on a one-dimensional nonlinear oscillator chain. We show that solutions with the initial form of the assumed ansatz preserve this form over time intervals with positive macroscopic length, and we show a bound on the possible shift of the envelope caused by the interaction. Thus, we rigorously justify and quantify the statement that under the given conditions there is almost no interaction of the modulated pulses. 相似文献
998.
Johnny Henderson 《Journal of Difference Equations and Applications》2013,19(7):1005-1018
We study the existence and non-existence of positive solutions of a system of nonlinear second-order difference equations with eigenvalues subject to multi-point boundary conditions. 相似文献
999.
S. Elaydi 《Journal of Difference Equations and Applications》2013,19(6):563-589
We present here a unified treatment of asymptotic theory of linear difference equations. This is based on anadapted theory of discrete dichotomy. The obtained results narrow the gap between Poincarés Theorem and (the discrete analoue of) Levinson's Theorem. 相似文献
1000.
Magdy H. Metry Allan R. Sampson 《Journal of computational and graphical statistics》2013,22(2):209-223
Abstract This article introduces an approach for characterizing the classes of empirical distributions that satisfy certain positive dependence notions. Mathematically, this can be expressed as studying certain subsets of the class SN of permutations of 1, …, N, where each subset corresponds to some positive dependence notions. Explicit techniques for it-eratively characterizing subsets of SN that satisfy certain positive dependence concepts are obtained and various counting formulas are given. Based on these techniques, graph-theoretic methods are used to introduce new and more efficient algorithms for constructively generating and enumerating the elements of various of these subsets of SN. For example, the class of positively quadrant dependent permutations in SN is characterized in this fashion. 相似文献