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61.
Cristinel Mortici 《Czechoslovak Mathematical Journal》2005,55(3):709-718
In this paper we give some new results concerning solvability of the 1-dimensional differential equation y′ = f(x, y) with initial conditions. We study the basic theorem due to Picard. First we prove that the existence and uniqueness result
remains true if f is a Lipschitz function with respect to the first argument. In the second part we give a contractive method for the proof
of Picard theorem. These considerations allow us to develop two new methods for finding an approximation sequence for the
solution. Finally, some applications are given. 相似文献
62.
It is proved that if μ and v be finite measures on a measurable space (X,S) and v is absolutely continuous with respect to v, then it is holds that L(^*S,^*v) C L(^*S,^*v), while L(^*S,^*v) and L(^*S,^*v) are the Loeb algebras with respect to measure spaces (X,S,μ) and(X,S,μ). 相似文献
63.
蔡建平 《Annals of Differential Equations》2004,20(1):14-20
This paper investigates the periodic boundary value problems for a class of second order functional differential equations. The monotone iterative technique and the maximum principle are applied to obtain the existence of maximal and minimal solutions. 相似文献
64.
65.
Using the full-potential linearized augmented plane wave (FP-LAPW) method, we have studied the effect of chemistry on the average intercalation voltage (AIV) caused by the Na ions intercalating into transition metal oxides. The effect of transition metal was systematically studied by varying M=Co, Ni and Mn in NaMO2 and fixing the α-NaFeO2 layered structure. The effect of the guest atoms into the host material is discussed in terms of the structural and electronic properties. Comparatively to Li intercalation, a significant electron transfer towards transition metal was found. This observation suggests that the transition metal contribute to the AIV determination and confirms the common assumption that intercalated electron reduces M4+ to M3+. 相似文献
66.
杜毅 《新疆大学学报(理工版)》2004,21(3):258-266
本文将讨论非终生免疫性传染病模型解的适定性及正则性;同时证明了整体解的存在,以及解对初值的连续依赖。 相似文献
67.
Framstad N. C. Øksendal B. Sulem A. 《Journal of Optimization Theory and Applications》2004,121(1):77-98
We give a verification theorem by employing Arrow's generalization of the Mangasarian sufficient condition to a general jump diffusion setting and show the connections of adjoint processes to dynamic programming. The result is applied to financial optimization problems. 相似文献
68.
Nicholas A. Loehr 《Discrete Mathematics》2004,280(1-3):233-236
This note generalizes André's reflection principle to give a new combinatorial proof of a formula for the number of lattice paths lying within certain trapezoids. 相似文献
69.
The authors establish the Hilbertian invariance principle for the empirical process of a stationary Markov process, by extending the forward-backward martingale decomposition of Lyons-Meyer-Zheng to the Hilbert space valued additive functionals associated with general non-reversible Markov processes. 相似文献
70.