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71.
The velocity of a particle detector in granular flow can be regarded as the combination of rolling and sliding velocities. The study of the contribution of rolling velocity and sliding velocity provides a new explanation to the relative motion between the detector and the local granular flow. In this study, a spherical detector using embedded inertial navigation technology is placed in the chute granular flow to study the movement of the detector relative to the granular flow. It is shown by particle image velocimetry (PIV) that the velocity of chute granular flow conforms to Silbert's formula. And the velocity of the detector is greater than that of the granular flow around it. By decomposing the velocity into sliding and rolling velocity, it is indicated that the movement of the detector relative to the granular flow is mainly caused by rolling. The rolling detail shown by DEM simulation leads to two potential mechanisms based on the position and drive of the detector. 相似文献
72.
从复杂网络的节点路径长度范围的角度来研究病毒传播的局域控制,分析了在不同拓扑结构的复杂网络中进行局域控制的有效性.研究表明,局域控制对WS小世界网络、BA无标度网络和ER随机网络三类复杂网络均有效,但只有WS小世界网络存在零感染的控制范围最优值d=3;对于长程连边的分布存在距离偏好的Kleinberg小世界网络,随着依赖度的增大,病毒传播率临界值增加,同时局域范围控制的效果得到加强.
关键词:
复杂网络
病毒传播
局域控制
路径长度 相似文献
73.
74.
A modified spatially extended Tang-Othmer Ca2+ model is used to study intracellular Ca2+ spiral waves numerically.It is found that,as a local stimulation,the local agonist-binding on the cell membrane,which enhances the local concentration of the messenger molecule inositol 1,4,5-trisphosphate(IP 3),can influence the dynamics of the spiral waves.1) Strong enough stimuli can change the spiral wave from a meandering to a rigidly rotating one.2) On the other hand,strong enough stimuli can suppress the spiral wave from the system.It provides the theoretical clue for controlling the spiral waves by stimulating the cell membrane. 相似文献
75.
Coherent control of negative refraction based on local-field enhancement and dynamically induced chirality 下载免费PDF全文
This paper studies the electromagnetic response of a coherently driven dense atomic ensemble to a weak probe.It finds that negative refraction with little absorption may be achieved in the presence of local-field enhanced interaction and dynamically induced chirality.The complex refractive index governing the probe refraction and absorption depends critically on the atomic density,the steady population distribution,the coherence dephasings,and the frequency detunings,and is also sensitive to the phase of the driving field because the photonic transition paths form a close loop.Thus,it can periodically tune the refractive index at a fixed frequency from negative to positive values and vice versa just by modulating the driving phase.Moreover,the optimal negative refraction is found to be near the probe magnetic resonance,which then requires the electric fields of the probe and the drive being on two-photon resonance due to the dipole synchronisation. 相似文献
76.
77.
Two isolated pentagon rule satisfying isomers of C76 are optimized. And 1(D2) isomer is reconfirmed to be the relative more stable one. The X-ray absorption near-edge structure (XANES) spectra are theoretically characterized by the hybrid density functional theory (DFT) method in combination with the full core-hole potentials. Isomer identification of XANES spectra for Cr6 is found and XANES spectra dependence on local structure of fullerene is discussed. 相似文献
78.
Effect of Lorentz local field correction on propagation of ultrashort laser pulse in one-dimensional para-nitroaniline (PNA) molecules 下载免费PDF全文
This paper investigates the effect of Lorentz local field correction (LFC) on the propagation of ultrashort laser pulses in a para-nitroaniline molecular medium under resonant and nonresonant conditions by solving numerically the full-wave Maxwell-Bloch equations beyond slowly-varying envelope approximation and rotating-wave approximation. The effect of the LFC is considerably obvious when pulses with large areas propagate in the dense molecular medium. In the case of resonance,the group velocity of the sub-pulses split from the incident pulse along propagation is severely decreased by the LFC,especially for the latest sub-pulse. However,in the case of nonresonance,the influence of the LFC on the temporal evolution of the pulse is less obvious and lacks homogeneity with an increase in incident pulse area,propagation distance and molecular density. 相似文献
79.
80.
Local discontinuous Galerkin method for solving Burgers and coupled Burgers equations 总被引:1,自引:0,他引:1 下载免费PDF全文
In the current work, we extend the local discontinuous Galerkin method to a more general application system. The Burgers and coupled Burgers equations are solved by the local discontinuous Galerkin method. Numerical experiments are given to verify the efficiency and accuracy of our method. Moreover the numerical results show that the method can approximate sharp fronts accurately with minimal oscillation. 相似文献