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排序方式: 共有1214条查询结果,搜索用时 15 毫秒
101.
In a Hilbert space H we consider evolution problems -du(t) A(t)u(t) on some interval [0, T], where every A(t): D(A(t)) 2 H is a maximal monotone operator, and the correspondence t A(t) is – in a suitable sense – of bounded variation or absolutely continuous. 相似文献
102.
This paper deals with -periodicity and regularity of solutions to the one dimensional nonlinear wave equation with -dependent coefficients
103.
M. I. D’yachenko 《Russian Mathematics (Iz VUZ)》2008,52(5):32-40
Earlier we introduced a continuous scale of monotony for sequences (classes M α, α ≥ 0), where, for example, M 0 is the set of all nonnegative vanishing sequences, M 1 is the class of all nonincreasing sequences, tending to zero, etc. In addition, we extended several results obtained for trigonometric series with monotone convex coefficients onto more general classes. The main result of this paper is a generalization of the well-known Hardy—Littlewood theorem for trigonometric series, whose coefficients belong to classes M α, where α ∈ ( $ \tfrac{1} {2} Earlier we introduced a continuous scale of monotony for sequences (classes M
α, α ≥ 0), where, for example, M
0 is the set of all nonnegative vanishing sequences, M
1 is the class of all nonincreasing sequences, tending to zero, etc. In addition, we extended several results obtained for
trigonometric series with monotone convex coefficients onto more general classes. The main result of this paper is a generalization
of the well-known Hardy—Littlewood theorem for trigonometric series, whose coefficients belong to classes M
α, where α ∈ (, 1). Namely, the following assertion is true.
Let α ∈ (, 1), < p < 2, a sequence a ∈ M
α, and . Then the series cos nx converges on (0,2π) to a finite function f(x) and f(x) ∈ L
p
(0,2π).
Original Russian Text ? M.I. D’yachenko, 2008, published in Izvestiya Vysshikh Uchebnykh Zavedenii, Matematika, 2008, No.
5, pp. 38–47. 相似文献
104.
Mostafa Nasri 《Optimization》2016,65(2):467-478
The analysis of the principal-agent problem usually requires the classical first-order approach (FOA). However, the validity of the FOA makes restrictive assumptions on the problem under consideration such as the convexity of the distribution function condition. The main aim of this paper is to compute the optimal wages and characterize a closed form solution to the risk-neutral principal-agent problem with limited liability constraints. The development in this paper mainly invokes certain techniques in the semi-infinite programming rather than the FOA. 相似文献
105.
In this article, we study the approximation of common zeros of non-self inverse strongly monotone operators defined on a closed convex subset C of a Hilbert space H. For a non-self family of operators, we introduce an iterative algorithm without relying on projections. Approximation of common fixed points for finite families of non-self strict pseudo-contractions in the sense of Browder-Petryshyn is also obtained. The novelty of our algorithm is that the coefficients are not given a priori and no assumptions are made on them, but they are constructed step by step in a natural way. 相似文献
106.
Javad Balooee Yeol Je Cho Mehdi Roohi 《Numerical Functional Analysis & Optimization》2016,37(3):284-303
A new class of contractive mappings called pointwise asymptotically ?-strict pseudo-contractions in Hilbert spaces is introduced and weak convergence of the sequence generated by Mann's iterative scheme to a fixed point of a uniformly Lipschitzian and pointwise asymptotically ?-strict pseudo-contractive mapping T in a Hilbert space is established. Also, a new kind of monotone hybrid method which is a modification of Mann's iterative scheme for finding a common fixed point of an infinitely countable family of uniformly Lipschitzian and pointwise asymptotically ?-strict pseudo-contractive mappings is proposed. Strong convergence of the sequence generated by the proposedmonotone hybrid method for an infinitely countable family of uniformly Lipschitzian and pointwise asymptotically ?-strict pseudo-contractive mappings in a Hilbert space is also shown. The results presented in this article extend and improve some known results in the literature. 相似文献
107.
邹庭桂 《新疆大学学报(理工版)》1987,(4)
本文运用微分不等式定理,定义了三阶拟线性全双曲方程特征问题的上下解,构造了收敛于特征问题解的一对上、下解单调序列,提供了寻求近似解的一种可行方法。 相似文献
108.
在自反Banach空间中引进并研究一类具有集值映射的广义强非线性变分不等式问题,并且证明了这类变分不等式解的存在性定理。结果修正、改进和推广了文献Cho Y.J等人的主要结果。 相似文献
109.
该文讨论了带有齐次超线性项μC和线性项D的混合单调算子A=B+μC+D的不动点的存在性.在不假设耦合下上解存在的条件下,得到了算子A的一个不动点定理,并且将所获结果应用到常微分方程两点边值问题、积分方程和椭圆型方程边值问题中,得到了新的结论.因而本质上推广和改进了已有的混合单调算子和相应的增算子的不动点定理. 相似文献
110.
Boubakari Ibrahimou Athanassios G. Kartsatos 《Nonlinear Analysis: Theory, Methods & Applications》2009,70(12):4350-4368
The purpose of this paper is to demonstrate the fact that the topological degree theory of Leray and Schauder may be used for the development of the topological degree theory for bounded demicontinuous (S+)-perturbations f of strongly quasibounded maximal monotone operators T in separable reflexive Banach spaces. Certain basic homotopy properties and the extension of this degree theory to (possibly unbounded) strongly quasibounded perturbations f are shown to hold. This work uses the well known embedding of Browder and Ton, and extends the work of Berkovits who developed this theory for the case T=0. Besides being an interesting mathematical problem, the existence of such a degree theory may, conceivably, become useful in situations where the use of the Leray–Schauder degree (via infinite dimensional compactness) is necessary. 相似文献