Dark soliton in one-dimensional Bose–Einstein condensate under a periodic perturbation of trap

The perturbation of a confining trap leads to the collective oscillation of a Bose--Einstein condensate, thereby the propagation of a dark soliton in the condensate is affected. In this study, periodic perturbation is employed to match the soliton oscillation. We find that the soliton dynamics depends sensitively on the coupling between the moving direction of the trap and that of the soliton. The soliton energy/depth evolves periodically, and a relevant shift in the soliton trajectory occurs as compared with the unperturbed case. Overall, the soliton oscillation frequency changes little even if the perturbation amplitude and frequency vary.     

Model for cascading failures with adaptive defense in complex networks

<正>This paper investigates cascading failures in networks by considering interplay between the flow dynamic and the network topology,where the fluxes exchanged between a pair of nodes can be adaptively adjusted depending on the changes of the shortest path lengths between them.The simulations on both an artificially created scale-free network and the real network structure of the power grid reveal that the adaptive adjustment of the fluxes can drastically enhance the robustness of complex networks against cascading failures.Particularly,there exists an optimal region where the propagation of the cascade is significantly suppressed and the fluxes supported by the network are maximal. With this understanding,a costless strategy of defense for preventing cascade breakdown is proposed.It is shown to be more effective for suppressing the propagation of the cascade than the recent proposed strategy of defense based on the intentional removal of nodes.     

阻尼作用下带对称双阱势的原子链中的洞孤子

采用多重尺度法,研究弱阻尼作用下带有对称双阱势的原子链,导出耗散型的非线性薛定谔方程,并对方程进行解析求解,给出阻尼作用下在链中传播的耗散型的洞孤子解.     

基于互补滤波的输电导线舞动轨迹还原算法

方向余弦矩阵算法(DCM算法)是工业级MEMS惯性传感器姿态解算常用算法。但由于受到外部机械振动和电磁环境影响,MEMS陀螺输出数据漂移较大,导致陀螺积分解算得出的姿态角误差会随着时间累积增长,因此须结合DCM算法与GPS或磁罗盘对陀螺计算出的角度进行误差修正。然而本文设计的导线舞动检测仪是直接安装于高电压架空输电线路表面,仪器处于很强的工频电磁干扰环境中,GPS和磁罗盘传感器失效,所以为了实时准确输出高压导线的运动轨迹,本文提出采用改进的DCM算法,即MEMS陀螺和加速度计的互补滤波算法;并设计出详细的导线舞动轨迹解算流程;最后以仿真测试验证该算法的正确性,并且在专用的舞动监测实验平台上证实了新型舞动监测仪样机的有效性。     

推导光栅衍射暗纹位置公式的简易方法

光栅衍射是普通物理等物理类教材中重要的必修内容．常用的普通物理教材对光栅衍射规律的描述通常忽略推导过程而只给出一些重要的结论,例如暗纹位置公式;或者仅作定性分析,例如明条纹宽度随缝数增多而变窄等．事实上,对于光栅衍射暗纹位置公式可以由振幅矢量法求解,     

Heat transport in coupled inhomogeneous chains

We first investigate the heat transport in a network model consisting of two coupled dimerized chains. Results indicate that the thermal resistance of each chain increases with the decrease of the mass ratio γ of the two types of atoms. Then, we find, when a light impurity or a heavy one is added in the two coupled homogeneous chains and coupled with a particle of another chain, the interface thermal resistances R_int^l and R_int^r present different dependences on the mass ratio γ'. Finally, a persistent circulation of energy current is observed in coupled inhomogeneous chains with two pairs of interchain coupling.     

Information diffusion on adaptive network

Based on the adaptive network, the feedback mechanism and interplay between the network topology and the diffusive process of information are studied. The results reveal that the adaptation of network topology can drive systems into the scale-free one with the assortative or disassortative degree correlations, and the hierarchical clustering. Meanwhile, the processes of the information diffusion are extremely speeded up by the adaptive changes of network topology.     

Immunization for scale-free networks by random walker

Based on the random walk and the intentional random walk, we propose two types of immunization strategies which require only local connectivity information. On several typical scale-free networks, we demonstrate that these strategies can lead to the eradication of the epidemic by immunizing a small fraction of the nodes in the networks. Particularly, the immunization strategy based on the intentional random walk is extremely efficient for the assortatively mixed networks.     

Link prediction based on a semi-local similarity index

Missing link prediction provides significant instruction for both analysis of network structure and mining of unknown links in incomplete networks. Recently, many algorithms have been proposed based on various node-similarity measures. Among these measures, the common neighbour index, the resource allocation index, and the local path index, stemming from different source, have been proved to have relatively high accuracy and low computational effort. In this paper, we propose a similarity index by combining the resource allocation index and the local path index. Simulation results on six unweighted networks show that the accuracy of the proposed index is higher than that of the local path one. Based on the same idea of the present index, we develop its corresponding weighted version and test it on several weighted networks. It is found that, except for the USAir network, the weighted variant also performs better than both the weighted resource allocation index and the weighted local path index. Due to the improved accuracy and the still low computational complexity, the indices may be useful for link prediction.     

中药复方的现代化研究

中医中药是中华民族在长期实践中积累和发展起来的伟大文化遗产,为中华民族的繁衍昌盛做出了巨大的贡献。中药复方（或称中药方剂）是中药用药的主要形式。它基于辩证的思想观点,按照君臣佐使的组方原则,选择恰当的药物定量配伍而成,是中医辩证论治理论的具体体现。中...