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151.
152.
首先,在不具有任何凸性结构的拓扑空间中引入Fan-Browder映射的概念.然后,证明了一个新的关于Fan-Browder映射的连续选择定理,其中定义域是非紧的,值域是不具有任何凸性结构的拓扑空间的子集.作为应用,给出了一些不动点定理、叠合点定理和一个非空交定理.这些新的概念和定理统一和推广了许多已有的结果. 相似文献
153.
丁协平 《应用数学和力学(英文版)》2005,26(12):1547
A new notion of finite continuous topological space (in short, FC-space)with out convexity structure was introduced. A new continuous selection theorem was established in FC-spaces. By applying the continuous selection theorem, some new coincidence theorems for two families of set-valued mappings defined on product space of noncompact FC-spaces are proved under much weak assumptions. These results generalize many known results in recent literature. Some applications will be given in a follow-up paper. 相似文献
154.
测量了Ti,Ni,Cu,Al以及Si的符合多普勒展宽谱。对于Ni的多普勒展宽谱,采用最小二乘法拟合得出其中的源强度。给出了源修正前后湮没量子在Si中的多普勒展宽谱,讨论了源成分的影响。用高斯-抛物线模型拟合多普勒展宽谱,将多普勒展宽谱中自由电子的湮没贡献和束缚电子的湮没贡献分开,进而探讨了只对束缚电子的湮没贡献做源修正的方法。In the present work, Coincidence Doppler Broadening (CDB) measurements have been performed for five elements i.e. Ti, Ni, Cu, Al and Si. As to the CDB spectra of Ni, we obtained the annihilation fraction of positron-electron pairs in the source by least square fitting. After source correction, spectra for Si are also given to indicate the influence of source components. CDB spectra were simulated with Gauss-Parabola model to separate annihilation contribution of core electrons from outermost electrons. Furthermore, a new source correction method, i.e. source correction will be done only in the contribution of core electron, has been presented 相似文献
155.
Graph‐theoretic method on the periodicity of multipatch dispersal predator‐prey system with Holling type‐II functional response 下载免费PDF全文
《Mathematical Methods in the Applied Sciences》2018,41(9):3323-3334
We study the periodicity of multipatch dispersal predator‐prey system with Holling type‐II functional response in this paper. By providing a new method, we overcome the difficulty to get the priori bounds estimation of unknown solutions of operator equation Lu=λNu. Graph theory with coincidence degree theory is used, and a sufficient criterion for the periodicity of the system is obtained. The criterion presented in this paper is closely related with topological structure of dispersal network and can be verified easily. Finally, a numerical example is also provided to verify the effectiveness of theoretical results. 相似文献
156.
157.
NEWVERSIONOFKKMTHEOREMINPROBABILISTICMETRICSPACESWITHAPPLICATIONSZhangShisheng(张石生)YeolJeCho(赵烈济)WuXiang(吴鲜)(ReceivedMay7,199... 相似文献
158.
159.
在Menger PM-空间中,引入广义β-可容许映射的概念。在不要求两映射可交换的情况下,利用迭代法,建立了广义β-可容许映射的二元重合点定理。获得了一些新的结果,推广和改进了相关文献中的不动点定理和二元重合点定理。最后,给出了主要结果的一个应用。 相似文献
160.
The phase change between periodic signals is regular. Research on the regular phenomenon between periodic signals is helpful to improve the precision of some measurements and develop some new measurement methods. So it is necessary to analyze the characteristics of the greatest common factor frequency and the least common multiple period universally existing in periodic signals. The regulation of the quantitative phase shift resolution between periodic signals is presented.The cause of difference in phase characteristics between periodic signals is explained well. In this paper we propose different application prospects based on the regular phenomenon between periodic signals, with focusing on the methods for high precision frequency measurement and transient stability measurement. The experimental results are satisfactory. 相似文献