巧用两只弹簧的组合 加深对简谐振动的理解

如果放在光滑桌面上的物体只受一只弹簧的作用，那么物体所作的运动是简揩运动．简谐运动是一种最简单的基本运动，它的动力学特点是物体所受合力满足F=-kx，该力叫回复力．简谐运动的特点是具有周期性，周期T=2π√m/k，其中m是振动物体质量，k是回复力     

常用通信接口技术的探讨

在过去两年里，用于消除IC、电路板和系统之间数据传输瓶颈的接口标准层出不穷，本文将就通信应用标准部件的某些最流行的标准进行分析，并研究众多新标准出现的原因，此外还探讨设计者如何解决互用性的难题。     

10GbE成为主流

数年来，具有10Gbps速度的下一代以太网一直处于即将成为主流的状况。一段时间以来，网络的某些区域已在使用光学技术，并且随着流量的增加，对10GbE数据速率的需求正在增长。但是，需要一种比上一代以太网复杂许多的技术，用于在100m长的铜缆上运行10GbE。这一要求导致了昂贵的MAC（媒体访问控制器）和交换芯片，以及昂贵而又不方便的PHY层接口芯片，由此限制了快速LAN用于那些覆盖数据中心内较短距离的高性能应用。     

下一代网格状光传送网的生存性探讨

随着网格状网拓扑在新一代光传送网中的应用，基于网格状网的光传送网生存性成为一个值得研究的课题。从光层保护入手，首先分析了网格状网生存性的主要特征；接着对网格状网的保护与恢复进行了总结与归纳，并介绍了不同保护机制的应用特点；最后对网格状网中多层联合保护策略进行了较为深入的探讨。     

液晶光阀光电导层光吸收系数的研究

用化学气相沉积法制备了液晶光阀中光电导层———非晶硅薄膜,从实验中得出最佳制备工艺的参数取值。给出了用包络线法测量非晶硅薄膜光吸收系数的原理,测量了样品的光吸收系数随波长的变化规律。得到样品在最佳工艺条件下的光吸收系数高于1×103cm-1。     

欠驱动系统Pendubot的模糊控制策略

本文针对欠驱动Pendubot机器人系统，提出一种简单可靠的摇起及平衡控制策略。通过利用模糊控制及全状态反馈控制技术来分别设计摇起控制器及平衡控制器，其中模糊摇起控制器的设计使得系统的摇起可靠性得到大大的加强，并缩短了响应时间，两个控制器的转换通过转换装置实现。最后的仿真结果验证了算法的有效性。     

近年西方国家通信网发展动态

首先说明西方国家通信网近年发展变迁情况，然后对IP与WDM的结合使用、光数据网的发展、密集波分多路的应用和光网中通路的保护4个主要方面作了具体说明。     

Experimental Creation of Entanglement Using Separable States

We experimentally demonstrate that the entanglement can be created on two distant particles using separable states. We show that two working particles can share some entanglement, while one ancilla particle always remains separable from the two working particles during the experimental evolution of the system. Our experiment can be viewed as a benchmark to illustrate the idea that no prior entanglement is necessary to create entanglement.     

Dissociative Chemisorption of an H2（v,j） Molecule on Rigid Ni （100） Surface： Dependence on Surface Topologies and Initial Rovibrational States of the Molecules

The H2(v,j) Ni(100) collision system has been studied to understand the effects of the surface sites and initial rovibrational states of the molecule on molecule-surface interactions, by a quasiclassical molecular dynamic simulation method. Dissociative adsorption of an H2 molecule on the rigid Ni(100) surface is investigated at topologically different three sites of the surface. Interaction between the molecule and Ni surface was described by a London-Eyring-Polani-Sato (LEPS) potential. Dissociative chemisorption probabilities of the H2(v, j) molecule on various sites of the surface are presented as a function of the translation energies between 0.001-1.0eV. The probabilities obtained at each collision site have unique behaviour. At lower collision energies, indirect processes enhance the reactivity, effects of the rotational excitations and impact sites on the reactivity are more pronounced. The results are compared with the available studies. The physical mechanisms underlying the results and quantum effects are discussed.     

Effects of External Electric Field on Ferroelectric Superlattice with Two Alternating Layers

The effects of the external electric field on the ferroelectric superlattice with two alternating layers have been studied using the transverse Ising model based on the effective-field theory with the differential technique. The hysteresis loops and susceptibility of the system have been given. The stronger the external electric field, the smaller the susceptibility, reflecting that the polarization is weaker.