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61.
Sergei Yu. Pilyugin 《Journal of Dynamics and Differential Equations》2007,19(3):747-775
We study the C
1-interiors of sets of diffeomorphisms of a closed smooth manifold with various limit shadowing properties. It is shown that,
for some natural analogs of the usual limit shadowing property, the corresponding C
1-interiors coincide with the set of Ω-stable diffeomorphisms. The same problem is considered for two-sided analogs of the
limit shadowing property.
To Pavol Brunovsky on the occasion of his 70th birthday. 相似文献
62.
We prove that any C1-stable weakly shadowable volume-preserving diffeomorphism defined on a compact manifold displays a dominated splitting E ⊕ F. Moreover, both E and F are volume-hyperbolic. Finally, we prove the version of this result for divergence-free vector fields. As a consequence, in low dimensions, we obtain global hyperbolicity. 相似文献
63.
We prove that the two-sided limit shadowing property is among the strongest known notions of pseudo-orbit tracing. It implies shadowing, average shadowing, asymptotic average shadowing and specification properties. We also introduce a weaker notion that is called two-sided limit shadowing with a gap and prove that it implies shadowing and transitivity. We show that those two properties allow to characterize topological transitivity and mixing in a class of expansive homeomorphisms and hence they characterize transitive (mixing) shifts of finite type. 相似文献
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66.
Second‐order statistics of system with N‐branch microdiversity and L‐branch macrodiversity operating over gamma shadowed Nakagami‐m fading channels
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Nikola M. Sekulović Mihajlo Č. Stefanović Daniela M. Milović Selena Ž. Stanojčić 《International Journal of Communication Systems》2014,27(2):390-400
The problem concerning short‐term fading and long‐term fading (shadowing) and their deleterious effects on wireless systems performance has been in focus for a long time. In this paper, motivated by the results of propagation measurements in land‐mobile and indoor‐mobile systems, and by the fact that gamma distribution can describe shadowing reliably, Nakagami‐m distribution is used to model the signal envelope and gamma distribution is used to model the average signal power. Receive diversity with maximal‐ratio combining and selection combining is implemented at the microlevel and macrolevel, respectively. The general case is explored, which assumes that microdiversity and macrodiversity are provided through arbitrary number of channels. Because shadowing has larger correlation distance than short‐term fading, correlated macrodiversity channels are studied. This paper investigates the dynamics of the received signal. A novel rapidly converging infinite‐series expression for average level crossing rate and average fade duration are obtained. Numerical results are graphically presented to examine the impact of fading severity, shadowing severity, number of diversity branches at the microlevel, number of base stations and correlation between base stations to the system's performance. Computer simulations are also performed to verify the validity and the accuracy of proposed theoretical analysis. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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跳-扩散模型下的再装期权定价 总被引:2,自引:0,他引:2
本文建立股票价格的跳过程为Poisson过程,跳跃高度服从对数正态分布时股票价格过程的随机微分方程,在风险中性的假设下找到等价鞅测度,利用鞅方法,用较简单的数学推导得到了股票价格服从跳-扩散过程的欧式再装期权定价公式. 相似文献
69.
Anewapproachforrealizingtheopticalmorphologicaldilationof1-DgrayimagesHUANGGuoliang;JINGuofan;WUMinxian;YANYingbai(Dept.o,Pre... 相似文献
70.
A Optical Scheme for Parallelly Realizing the Morphological Erosion of 1-D Gray ImagesAOpticalSchemeforParallellyRealizingthe... 相似文献