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121.
An Affirmative Result of the Open Question on Determining Function Jumps by Spline Wavelets
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We study the open question on determination of jumps for functions raised by Shi and Hu in 2009. An affirmative answer is given for the case that spline-wavelet series are used to approximate the functions. 相似文献
122.
In this paper, we calculate the number of spanning trees in prism and antiprism graphs corresponding to the skeleton of a prism and an antiprism. By the electrically equivalent transformations and rules of weighted generating function, we obtain a relationship for the weighted number of spanning trees at the successive two generations. Using the knowledge of difference equations, we derive the analytical expressions for enumeration of spanning trees. In addition, we again calculate the number of spanning trees in Apollonian networks, which shows that this method is simple and effective. Finally we compare the entropy of our networks with other studied networks and find that the entropy of the antiprism graph is larger. 相似文献
123.
Bo Chen Fangyue Chen Junbiao Guan Genaro J. Mart ''{ i}nez 《Journal of Applied Analysis & Computation》2016,6(4):1164-1179
By introducing a sequence-block transformation and vector-block transformation, we explore the dynamical properties of hybrid cellular automation (HCA) and hybrid cellular automation with memory (HCAM) in the framework of symbolic dynamics. As the local evolution rules of HCA and HCAM are not-uniform, the new uniform cellular automata (CAs) with multiple states are constructed by specifical the block transformations. Furthermore, because the new CA rules are topologically conjugate with the originals, the complex dynamics of the HCA and HCAM rules can be investigated via the new CA rules. 相似文献
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125.
本文研究了两个离散网络之间的广义同步,其中每个网络的节点动力学是不同的,节点数目也没有要求是相等的.通过使用辅助系统方法,我们给出了基于李雅普诺夫稳定性理论的广义同步定理.最后,用数值例子来验证定理的有效性. 相似文献
126.
《Communications in Nonlinear Science & Numerical Simulation》2010,15(9):2536-2545
In this paper, the problem of synchronizing two chaotic gyros in the presence of uncertainties, external disturbances and dead-zone nonlinearity in the control input is studied while the structure of the gyros, parameters of the dead-zone and the bounds of uncertainties and external disturbances are unknown. The dead-zone nonlinearity in the control input might cause the perturbed chaotic system to show unpredictable behavior. This is due to the high sensitivity of these systems to small changes in their parameters. Thereby, the effect of these issues should not be ignored in the control design for these systems. In order to eliminate the effects from the dead-zone nonlinearity, in this paper, a robust adaptive fuzzy sliding mode control scheme is proposed to overcome the synchronization problem for a class of unknown nonlinear chaotic gyros. The main contribution of our paper in comparison with other works that attempt to solve the problem of dead-zone in the synchronization of chaotic gyros is that we assume that the structure of the system, uncertainties, external disturbances, and dead-zone are fully unknown. Simulation results are provided to illustrate the effectiveness of the proposed method. 相似文献
127.
本文采用直流磁控溅射法在三种不同的下电极(BEs)上制备了ZnO薄膜, 获得了W/ZnO/BEs存储器结构. 研究了不同的下电极材料对器件电阻开关特性的影响. 研究结果表明, 以不同下电极所制备的器件都具有单极性电阻开关特性. 在低阻态时, ZnO薄膜的导电机理为欧姆传导, 而高阻态时薄膜的导电机理为空间电荷限制电流. 不同下电极与ZnO薄膜之间的肖特基势垒高度对电阻开关过程中的操作电压有较大的影响, 并基于导电细丝模型对不同下电极上ZnO薄膜的低阻态阻值及reset电流的变化进行了解释.
关键词:
ZnO薄膜
电阻开关
下电极 相似文献
128.
The real rectangular tensors arise from the strong ellipticity condition problem in solid mechanics and the entanglement problem in quantum physics. In this paper, we study the singular values/vectors problem of real nonnegative partially symmetric rectangular tensors. We first introduce the concepts of l k,s -singular values/vectors of real partially symmetric rectangular tensors. Then, based upon the presented properties of l k,s -singular values /vectors, some properties of the related l k,s -spectral radius are discussed. Furthermore, we prove two analogs of Perron-Frobenius theorem and weak Perron-Frobenius theorem for real nonnegative partially symmetric rectangular tensors. 相似文献
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130.
研究一类微分-差分方程组的对称和等价群变换.采取内禀的无穷小算子方法,给出了方程组的内禀对称和等价群变换.为结合抽象Lie代数结构,给方程完全分类提供了理论基础. 相似文献