Modeling Dynamic Evolution of Online Friendship Network

In this paper,we study the dynamic evolution of friendship network in SNS (Social Networking Site).Our analysis suggests that an individual joining a community depends not only on the number of friends he or she has within the community,but also on the friendship network generated by those friends.In addition,we propose a model which is based on two processes:first,connecting nearest neighbors;second,strength driven attachment mechanism.The model reflects two facts:first,in the social network it is a universal phenomenon that two nodes are connected when they have at least one common neighbor;second,new nodes connect more likely to nodes which have larger weights and interactions,a phenomenon called strength driven attachment (also called weight driven attachment).From the simulation results,we find that degree distribution P(k),strength distribution P(s),and degree-strength correlation are all consistent with empirical data.     

Three-dimensional flow driven pore-crack networks in porous composites: Boltzmann Lattice method and hybrid hypersingular integrals

This study introduces a hybrid hypersingular integral equation-Lattice Boltzmann method (HHIE-LBM) for analyzing extended 3D flow driven pore-crack networks problem in various porosity composites. First, the extended hybrid electronic-ionic, thermal, magnetic, electric and force coupled fields’ pressure and velocity boundary conditions for HHIE-LBM model are established, and the closed form solutions of extended distribution functions are given. Second, an extended 3D flow driven pore-crack networks problem in various porosity composites is translated into a coupled of HHIE-LBM equations, and the pore-crack networks propagation parameters are analyzed. Third, the extended dynamic stress intensity factors (EDSIFs) are calculated by using the parallel numerical technology and the visualization results are presented. Last, the relationship between the EDSIFs and the differential porosity is discussed, and several rules have been found, which can be utilized to understand the extended fluid flow mechanism in various porosity composites and analyze the extended fluid flow varying mechanism on coseismal slip.     

Dynamic Behavior of Entanglement Between Two Spatially Separated Atoms in Two Dissipative and Driven Cavity Fields

We consider two two-level atoms, interacting with two independent dissipative cavities, each of which is driven by an external source. The two cavity fields are both initially prepared in the coherent states, and the two two-level atoms are initiallyprepared in the singlet state |Ψ^-1 >=(|eg>-|ge>)/2^-1/2. We investigate the influence of the damping constant κ, the intensity of the external sources F,and the relative difference of the atomic couplings r on the entanglement between the two atoms. In the dispersive approximation, we find that the entanglement between the two atoms decreases with the time evolution, and the decreasing rate of entanglement depends on the values of F/κ, κ/ω, and r. For the givensmall values of F/κ and κ/ω, on the one hand, the increasing of r favors entanglement decreasing of the atomic system, on the other hand, when r→1 the entanglement decreasing becomes slower. With the increasing of the value ofκ/ω, the influence of r on the decreasing rate of entanglement becomes smaller, and gradually disappears for the big value of κ/ω.     

Study of the Katz–Lebowitz–Spohn model. The influence of an oscillatory driving field

The classic Katz–Lebowitz–Spohn (KLS) model is a lattice gas driven by an external field. In this paper, we study the critical behavior of the KLS model driven by an oscillatory field of strength E and period τ by means of both, Monte Carlo simulations and a coupled-map-lattice mean-field approach. It is found that, keeping the amplitude constant and changing the period, a novel phase transition between a non-equilibrium-stationary-state and an almost equilibrium-stationary-state takes place at a certain critical value τ_c.     

用单片机驱动线阵CCD的探讨

本文就弥补以往用单片机产生线阵 CCD驱动时序的不足进行了探讨 ;给出了使用 AVR单片机产生驱动TCD12 0 6线阵 CCD的具体实例及相应程序。其定时关系精确 ,驱动频率达到推荐的速率     

化学驱动的[2]轮烷型分子梭

机械互锁的轮烷型分子梭在分子机器化学领域具有重要的位置,可通过"积小为大"的方法在分子水平进行新材料的自组装.在外界的刺激下,大环分子可以在轴分子的不同识别位点间或态间往复穿梭,从而引起体系物理或化学性质的交替变化,这种变化又构成了一类基本的机械开关,可以用来执行特定的功能,在分子开关、信息储存和处理等领域具有潜在的应用前景,是超分子化学领域的研究热点.本文以[2]轮烷型分子梭的驱动力(外部刺激)为主线,分别从酸碱驱动、离子配位作用驱动和溶剂极性改变引起的疏水驱动等角度,综述了近年来化学驱动的[2]轮烷型分子梭在合成和应用方面的最新研究进展,同时介绍了其他力(如热力学参数熵、互锁体系中修饰基团尺寸大小、外加化学氧化剂或还原剂、得失电子引起的电化学氧化还原以及紫外-可见光照射诱发的偶氮苯顺反光异构化等方式)驱动的轮烷型分子梭的进展,最后对化学驱动的[2]轮烷型分子梭的未来发展趋势进行了展望.     

Exact wave functions for atomic electron interacting with photon fields

Many nonlinear quantum optical physics phenomena need more accurate wave functions and corresponding energy or quasienergy levels to account for. An analytic expression of wave functions with corresponding energy levels for an atomic electron interacting with a photon field is presented as an exact solution to the Schrödinger-like equation involved with both atomic Coulomb interaction and electron-photon interaction. The solution is a natural generalization of the quantum-field Volkov states for an otherwise free electron interacting with a photon field. The solution shows that an Nlevel atom in light form stationary states without extra energy splitting in addition to the Floquet mechanism. The treatment developed here with computing codes can be conveniently transferred to quantum optics in classical-field version as research tools to benefit the whole physics community.     

Effects of Ions Charge-Mass Ratio on Energy and Energy Spread of Accelerated Ions in Laser Driven Plasma

Effects of ions charge-mass ratio on energy and energy spread of accelerated ions in laser driven plasma are investigated in detail by proposing a simple double-layer model for a foil target driven by an ultrastrong laser. The radiation pressure acceleration mechanism plays an important role on the studied problem. For the ions near the plasma mirror, i.e. electrons layer, the dependence of ions energy on their charge-mass ratio is derived theoretically. It is found that the larger the charge-mass ratio is, the higher the accelerated ions energy gets. For those ions far away from the layer, the dependence of energy and energy spread on ions charge-mass ratio are also obtained by numerical performance. It exhibits that, as ions charge-mass ratio increases, not only the accelerated ions energy but also the energy spread will become large.     

磁驱动准等熵加载下Z切石英晶体的折射率

基于CQ4脉冲功率实验装置开展了Z-切石英晶体在磁驱动准等熵加载下的窗口折射率修正关系研究. 实验中采用激光波长1550 nm的双源光外差测速仪测量获得了LiF窗口和Z-切石英晶体窗口与不同厚度极板界面的粒子速度. 利用反积分方法由实验测得的LiF窗口与极板界面粒子速度计算得到了极板的加载磁压力历史; 以获得的磁压力为输入条件, 采用LS-DYNA计算软件正向计算得到石英晶体窗口与极板界面的真实粒子速度历史. 由实验获得的Z-切石英晶体窗口/极板界面表观粒子速度和计算得到的真实粒子速度, 获得了Z-切石英晶体弹性极限内的连续的折射率修正关系, 将其折射率修正关系的适用压力范围拓宽至14.55 GPa. 表观粒子速度与真实粒子速度关系采用线性拟合时, 折射率修正关系为n=1.087 (± 0.008)+0.4408ρ/ρ₀, 与冲击数据拟合的结果一致. 由折射率实验数据对Z-切石英晶体的极化率分析认为, 在其弹性极限压力范围内加载路径和温度对折射率的影响可以忽略.     

燃烧驱动连续波氟化氢(氘)化学激光器——三维列阵小孔喷管研究

文章针对燃烧驱动连续波氟化氢激光器分析了其喷管出口后的混合过程;同时也讨论了喷管设计参数、结构和加氢方式等对激光器输出功率、比功率的影响。实验表明在主喷管和副喷管之间混合距离为1.75mm时,用这种喷管的氟化氢激光器,比功率可达到 130J/g。