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71.
In the present paper, some new almost fixed point theorems and fixed point theorems for lower semicontinuous type multivalued mappings are obtained in metrizable H-spaces. 相似文献
72.
Based on new deformation theorems concerning strongly indefinite functionals, we give some new min-max theorems which are useful in looking for critical points of functionals which are strongly indefinite and satisfy Cerami condition instead of Palais-Smale condition. As one application of abstract results, we study existence of multiple periodic solutions for a class of non-autonomous first order Hamiltonian system
73.
IP Wai-Cheung WONG Heung XIE Zhongjie & LUAN YihuiDepartment of Applied Mathematics Hong Kong Polytechnic University Hong Kong China Department of Probability Statistics Peking University Beijing China 《中国科学A辑(英文版)》2004,47(1):52-64
The main purpose of this paper is to investigate the detection of jump points of a discontinuous function in the presence of a noise by the wavelet approach. A computing algorithm of our method is proposed and then applied to the daily exchange rate of US Dollar against Deutsche Mark. All the points detected by our method reflect very strong economic and political impacts. Other statistical methods to detect jump points have also been applied to the same exchange rate data. Our proposed method has produced more convincing empirical results than others. 相似文献
74.
In this paper, by the use of a fixed point theorem, many new necessary and sufficient conditions for the existence of positive solutions in C[0,1]∩C1[0,1]∩C2(0,1) or C[0,1]∩C2(0,1) are presented for singular superlinear and sublinear second-order boundary value problems. Singularities at t=0, t=1 will be discussed. 相似文献
75.
聚合公理系统的布尔值模型 总被引:2,自引:1,他引:2
本文以ZFc聚合公理系统为基础,构造了ZFc的布尔值模型,证明了关键定理9、定理15,使得ZF集合公理系统的布尔值模型VOn^(B)是聚合公理系统的布尔值模型〔VON^(B)〕的子模型,并且ZF集合公理组在〔VON^(B)〕中满足。 相似文献
76.
Nguyen Ngoc Luan 《Applicable analysis》2013,92(9):1694-1704
This paper establishes several new facts on generalized polyhedral convex sets and shows how they can be used in vector optimization. Among other things, a scalarization formula for the efficient solution sets of generalized linear vector optimization problems is obtained. We also prove that the efficient solution set of a generalized linear vector optimization problem in a locally convex Hausdorff topological vector space is the union of finitely many generalized polyhedral convex sets and it is connected by line segments. 相似文献
77.
利用单调迭代方法,在Banach空间研究了更为一般脉冲微分方程的初值问题的最小最大拟解的存在性及迭代逼近程序。 相似文献
78.
79.
Fu-bao Zheng Chang-wen Zhang Pei-ji Wang Hang-xing Luan 《Solid State Communications》2012,152(14):1199-1202
The electronic and magnetic properties of N-doped ZnO nanosheets are investigated by density functional theory using local spin density approximation. The results show that in an isolated N-doped ZnO nanosheet, there is a clear spontaneous polarization of N 2p state with a magnetic moment 1.0 μB/N. We also find that the doped nitrogen atoms in ZnO nanosheets have a clustering tendency with ferromagnetic coupling between them, and thus a high room-temperature ferromagnetic nature is expected. The ferromagnetic coupling in N-doped ZnO nanosheets can be attributed to the hole-mediated double-exchange mechanism through strong p–d interaction between nitrogen and zinc atoms. 相似文献
80.
理想气体的温度、体积和压强三个状态参量之间的关系由气体状态方程pV/T=恒量决定。当气体状态发生变化时,判断某一个参量的变化趋势是一个比较复杂的问题。如图1,为p—T图中的状态变化曲线,状态由A变化到B,判断体积的变化趋势。 相似文献