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排序方式: 共有642条查询结果,搜索用时 31 毫秒
1.
In this paper we investigated the stability of fractional order fuzzy cellular neural networks with leakage delay and time varying delays. Based on Lyapunov theory and applying bounded techniques of fractional calculation, sufficient criterion are established to guarantee the stability. Hybrid feedback control is applied to derive the proposed results. Finally, numerical examples with simulation results are given to illustrate the effectiveness of the proposed method. 相似文献
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In Mader (2010), Mader conjectured that for every positive integer and every finite tree with order , every -connected, finite graph with contains a subtree isomorphic to such that is -connected. In the same paper, Mader proved that the conjecture is true when is a path. Diwan and Tholiya (2009) verified the conjecture when . In this paper, we will prove that Mader’s conjecture is true when is a star or double-star and . 相似文献
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《Discrete Mathematics》2021,344(12):112601
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PVDF, poly(vinylidene fluoride), as a semi-crystalline polymer, has interesting electroactive properties but usual melt and solution processing techniques result in its thermodynamically favored non-polar α-phase. By comparison, poly(vinylidene fluoride-trifluoroethylene) P(VDF-TrFE), PT for short, directly crystallizes in the polar β-phase under the same conditions as PVDF. In this study, blend thin films comprising PVDF and P(VDF-TrFE) were prepared by solvent casting method. The difference in the crystallization behavior is comprehensively investigated between the polymers: PVDF, P(VDF-TrFE), and the resulting blend films. It is found that replacement of the fluoride atom in TrFE monomer induces a strong steric hindrance that may alter the crystallization process to become more favorable for nucleation of the PVDF β-phase. To figure out the effect of TrFE content on the crystallization behavior and electroactive properties, films with different blend ratios of PVDF and P(VDF-TrFE) were prepared. We found that the PVDF films exhibit higher crystallization activation energy (ΔE) as PT content increases. The atomic force microscopy (AFM) in the piezoresponse force microscopy (PFM) mode illustrated that P5T5 films with equal contents of PVDF and P(VDF-TrFE) induced the highest d33 values. 相似文献
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Wei Xiong Jinquan Xu Zhengke Miao Yang Wu Hong-Jian Lai 《Discrete Mathematics》2017,340(12):2995-3001
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Threshold dynamics of a nonlinear multi‐group epidemic model with two infinite distributed delays 下载免费PDF全文
Xiaomei Feng Kai Wang Fengqin Zhang Zhidong Teng 《Mathematical Methods in the Applied Sciences》2017,40(7):2762-2771
The global stability of equilibria is investigated for a nonlinear multi‐group epidemic model with latency and relapses described by two distributed delays. The results show that the global dynamics are completely determined by the basic reproduction number under certain reasonable conditions on the nonlinear incidence rate. Moreover, compared with the results in Michael Y. Li and Zhisheng Shuai, Journal Differential Equations 248 (2010) 1–20, it is found that the two distributed delays have no impact on the global behaviour of the model. Our study improves and extends some known results in recent literature. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Characterizations of the BMO and Lipschitz Spaces via Commutators on Weak Lebesgue and Morrey Spaces
Acta Mathematicae Applicatae Sinica, English Series - We prove that the weak Morrey space WM is contained in the Morrey space $$M_{{q_1}}^p$$ for 1 ≤ q1 < q ≤ p < ∞.... 相似文献
9.
Generalized synchronization of discrete systems 总被引:1,自引:0,他引:1
Generalized synchronization of two discrete systems was discussed. By constructing appropriately nonlinear coupling terms, some sufficient conditions for determining the generalized synchronization between the drive and response systems were derived. In a positive invariant and bounded set, many chaotic maps satisfy the sufficient conditions. The effectiveness of the sufficient conditions is illustrated by three examples. 相似文献
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