一种基于Q-Learning策略的自适应移动物联网路由新算法

针对移动物（车）联网的路由问题,通过对车辆的运动特点及造成链路断裂的原因进行的详细分析,我们建立了链路维持时间模型,并将维持时间作为设计路由算法的重要参数.Q-Learning作为一种启发式机器学习策略,能够通过与周围环境交互来动态地调整路由路径.基于此,我们设计了一种自适应的路由新算法.它将学习任务分散在每一个车辆节点中,通过周期性的与周围节点交换信标信息来维护可靠的路由路径.利用NS-2模拟器对该算法的性能进行了评估,结果表明,在不同的网络场景中,该算法在递交率、端到端的延时以及平均跳数等方面均表现出很好的效果.     

软件定义网络一致性协同更新算法

为实现软件定义网络的一致性更新,本文提出一种协同利用分段路由、顺序更新、两步复制三种机制的更新算法.算法首先启用分段路由机制,尝试用现有路径规则拼接待更新数据流的最终路径,并根据最终路径是否能由现有规则拼接,将数据流分为可拼接与不可拼接两种.对于可拼接流,分段路由可将最终路径信息封装入数据包包头,使得数据包能立即沿最终路径转发.对于不可拼接流,算法计算最长一致性更新序列,并按照此序列依次更新节点,最后利用两步复制机制来完成剩余未更新节点的更新.并且经实验验证,算法比之前研究提出的算法不仅消耗更少的三态内容寻址存储器的空间资源,并且有更好的适用性与稳定性.     

面向绿色互联网的低功耗多播路由算法

基于路径节点驱动策略,提出了一种绿色互联网中的一对多组播路由算法,充分利用路径节点共享路径,生成低功耗最短路径树,提高用户QoS满意度。基于CERNET2拓扑仿真实现了该算法,通过与现有的能量感知启发式路由算法在网络功耗、路由成功率和运行时间等方面的性能对比,表明本文提出的算法具有更好的性能。     

一种基于蚁群算法和非线性长度的多约束路由算法

在分析了多种路由算法的基础上,设计了一种基于蚁群算法的多约束路由算法。该算法采用了非线性路径长度,通过蚂蚁的周游获得长度更短的多约束路径。仿真表明,该算法在最短路径获取和路由发现成功率方面都有高效的表现。     

移动自组网模糊逻辑QoS动态源路由算法

该文提出了一种新的移动Ad hoc网络QoS路由算法:模糊逻辑QoS动态源路由算法。算法从模糊理论的思想出发,将业务的多个QoS参数进行综合评判产生一类以语言变量描述的请求,在修改动态源路由协议为多径路由算法的基础之上,对比各条路径综合模糊路由状态,选择出最适合业务请求的路径。仿真显示算法在支持QoS的同时对移动Ad hoc网络因拓扑动态变化而引起的信息不精确性有很好的适应度。     

一种传感器网络的分布式多播路由优化算法

传感器感知的信息需要通过网络传送给感兴趣目标节点,传统网络中的多播技术往往能耗高、实时性不够理想,不利于在传感器网络中使用。针对 WSN中节点对网络拓扑未知,该文先将多播路由问题演化为最优多播路径问题,通过启发式算法求解分布式最优路径,并通过一种基于贪婪思想的裁剪合并策略优化多播路由树,直至整个网络得到最优路径,最后并结合了节点区域集中以及无线多播特性,提出了 DCast 路由算法。最后通过仿真实验与uCast, SenCast等经典的传感器网络的多播路由算法仿真比较,可以得出其算法在时延性以及能耗等方面性能有优势。     

无线传感器网络高可靠低维护地理路由协议

无线传感器网络地理路由协议要求节点根据少量本地路由信息将数据分组传输路由到目标节点。为了消除路由环,地理路由算法通常需要将网络拓扑平面化。然而现有的平面化算法要么假设节点的通信半径是一固定值,在实际应用中不适用;要么对每一条链路都进行检测是否有交叉链路,路由维护代价很高。针对以上问题,提出一种具有高可靠性和低维护成本的地理路由协议RPR(region partitioning-based routing),其基本思想是将网络划分为规则多边形区域,并在贪心路由失败时将多边形区域内的所有节点看作一个虚拟节点进行周边路由。多边形区域间通信能够降低平均路由路径长度,从而提高了路由的可靠性。基于区域划分的网络平面化策略不需要检测和删除相交链路,因此减少了路由维护开销。模拟实验结果显示,RPR协议比现有方法的平均路由路径长度更短,路由维护开销更低。     

基于AODV且考虑拓扑信息的节能路由算法

提出了一种基于AODV的节能路由算法EBF-AODV.该算法在路由发现过程中,源节点设置一个阈值,中间节点根据本节点拓扑变化情况决定如何处理路由请求分组,目的节点综合考虑路径上的可用能量和路由跳数,选择最佳路径.通过仿真证明了该算法的有效性.     

基于可靠路径稳定性估计的MANET路由发现算法研究

提出一种基于可靠路径剩余生存期（RPL, residual path lifetime）估计的MANET路由发现算法（RLE-RPLP）,该算法充分考虑相邻链路剩余生存期相关性,建立优化的多跳路径RPL统计特性分析,提供了更可靠的路由稳定性评估。通过仿真分别与忽略链路RLL相关性的源路由协议及已有稳定性路由协议进行对比。仿真结果表明,RLE-RPLP算法能有效提高网络吞吐量并减少路由重建次数;当节点移动度较高或网络负载较大时,在吞吐量、路由开销等方面均优于已有的稳定性路由对比算法。     

基于业务感知和策略选择的认知路由算法

提出了一种基于业务感知和策略选择的认知路由(cognitive network routing)算法。该算法面向认知网络环境综合考虑了网络资源、业务流、策略选择等要素,在获知网络中业务流的宏观特征和需求的前提下,首先通过离线资源分配将网络资源按照业务流的固有分配特征预先配置给不同类型的业务流,然后通过在线路径计算实时得出各个业务流的最优路径。仿真实验验证了认知路由算法的有效性,对比于MIRA、SWP路由算法,CNR算法可以提高网络资源利用率,避免因资源不均衡产生的网络拥塞,能够在业务流和资源2个层面优化网络性能。     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Nanoimprint Lithography -A Next Generation High Volume Lithography Technique

IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.     

Influence of PVK ： NPB hole transporting layer on the characteristics of organic light-emitting devices

A doping system consisting of NPB and PVK is employed as a composite hole transporting layer （CHTL）. By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK ： NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK ： NPB at 1：3.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.     

Analysis of error performance on Turbo coded FDPIM

Due to variable symbol length of digital pulse interval modulation（DPIM）, it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation（FDPIM） method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.