Pair correlations in scale-free networks

Correlation between nodes is found to be a common and important property in many complex networks. Here we investigate degree correlations of the Barabasi－Albert (BA) scale-free model with both analytical results and simulations, and find two neighbouring regions, a disassortative one for low degrees and a neutral one for high degrees. The average degree of the neighbours of a randomly picked node is expected to diverge in the limit of infinite network size. As a generalization of the concept of correlation, we also study the correlations of other scalar properties, including age and clustering coefficient. Finally we propose a correlation measurement in bipartite networks.     

激光双光栅法测微小位移中光拍信号波形改进

通过理论分析和计算机模拟方法,对激光双光栅法测微小位移实验中出现的不规则光拍信号波形,即“毛刺”现象进行讨论,提出了改进双光栅微振动实验的方法,并获得了好的结果     

Strain and Phonon Confinement in Self－Assembled Ge Quantum Dot Superlattices Superlattices ＊

Raman scattering measurements were carried out in self-assembled Ge quantum dot superlattices grown bymolecular beam epitaxy. The characteristics of the Ge-Ge, Si-Ge, Si-SiLoc and Si-Si peaks were investigated,especially the Ge-Ge optical phonon frequency shift was emphasized, which was tuned by the phonon confinementand strain effects. The experimentally observed frequency shift values of the Ge-Ge peak frequency caused byoptical phonon confinement and strain in Ge quantum dots were discussed with quantitative calculations.