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1.
介绍了用备份路由实现主动网资源预留再协商技术。研究出一种新的网络路由算法,由于采用矩阵降阶变换方式并遵循逻辑代数运算规则计算,因此绝对收敛且易于编程实现。算法适用于任何复杂拓扑结构的网络路由计算,一次性计算可得到符合通信传输规则的端到端全部路由,并弥补了以往算法无法获得全部路由的缺陷。举例证明算法的正确性,简要介绍了路由算法应用于主动网资源预留再协商问题上的一些具体参考措施。  相似文献   

2.
介绍了在链路状态路由协议中的一次性签名算法的应用,然后以距离向量路由协议中的B.R.Smith等的路由认证方案为研究对象,提出了一次性认证算法在距离向量路由协议中的应用方法,分析了其产生的作用。  相似文献   

3.
一种无线传感器网路由算法的设计与实现   总被引:1,自引:0,他引:1  
孙强  徐晨  袁红林  包志华 《电子工程师》2006,32(12):67-69,80
讨论了无线传感器网络的特殊性,分析了其路由算法的需求。借鉴Ad Hoc网中比较成熟的AODV(Ad Hoc按需平面距离矢量)协议和DSR(动态源路由)协议,采用了按需驱动的路由策略,优化了路由建立和维护算法,提出了RODR(简化的按需路由)协议。采用该路由算法的网络协议已在由ATmega128L微处理器和CC2420构成的节点机上实现,通过组网实验,初步验证了其可行性。  相似文献   

4.
一种贪婪地理路由协议的改进算法   总被引:1,自引:0,他引:1  
《现代电子技术》2016,(11):16-20
贪婪转发策略广泛应用于无线传感网络(WSNs)的地理路由协议中,但是,该协议存在数据包丢失严重以及在遭遇路由空洞时路由效率低下的不足。为此,提出一种贪婪地理路由协议的改进算法,记为GPSR-I算法。GPSR-I算法在选择下一跳转发节点时,利用节点离目的节点距离、方向以及节点密度信息计算度量值,然后依据该度量值决策下一跳转发节点。仿真数据表明,与GPSR相比,GPSR-I算法能够有效降低平均端到端传输时延、路由开销,并提高了数据包传输率。  相似文献   

5.
0624342按需自组织路由算法的设计[刊,中]/杨甫//信息安全与通信保密.—2006,(6).—94-97(L)按需自组织路由算法是一种按需方式的分布式路由算法,它把网络路由的自组织和移动用户位置管理两种独立的功能有机地结合起来,减少了在网络自组织时算法对网络资源的消耗,提高了路由算法的效率。论文介绍了无线移动自组织互联网络的系统体系结构以及当前具有代表性的自组织算法,详细描述了我们设计使用的一种按需自组织路由算法的操作与设计。参8 0624343 IDS误报漏报率的计算和检测方法[刊,中]/姜春祥//信息安全与通信保密.—2006,(6).—90-91(L) 0624344 Loewner矩阵Moore-Penrose逆的快速算法[刊,中]/仝秋娟//合肥工业大学学报(自然科学版).—2006,29 (6).—798-800(C).0624345混沌最优化算法在结构最优化设计中应用[刊,中]/高健//合肥工业大学学报(自然科学版).—2006,29 (6).—751-754(C)  相似文献   

6.
针对无线传感器网络路由算法中的3维空洞问题,该文提出3维胞元空间路由(3D Cell Space Routing,3D-CSR)算法.该算法针对贪婪算法中空洞区域无法路由的情况,利用3维胞元空间模型将这些空洞区域的边界加以确定,进一步运用胞元路由机制完成路由过程.同时,单个胞元内部采用了自适应选举机制,使其中的胞父节点保持活跃并参与路由而其余胞子节点保持休眠状态,以平衡网络能量消耗.仿真结果验证了3维胞元空间模型与3D-CSR 算法的正确性和有效性,与3D-GPR(3D Grid Position-based Routing)和3D-CFace (3D Coordinate Face)算法比较,3D-CSR 的消息发送率与节点存活率更高.  相似文献   

7.
以AODV(无线自组网按需平面距离矢量路由)协议为原型,针对WMN(无线Mesh网)中传统AODV协议路由判据单一从而导致路由性能较差的缺陷,采用跨层设计方法为WMN设计了一种新的IAODV(优化的AODV)协议。在路由计算过程中通过跨层操作机制提取节点当前负载和链路投递率这两个影响链路质量的因素,结合路由跳数设计出合理的路由判决函数。理论分析和NS2仿真结果证明,这种路由优化机制提高了吞吐量,降低了网络时延,并且能够达到负载均衡的路由效果。  相似文献   

8.
TrANTHOCNET:信任性蚁群自组织路由算法   总被引:1,自引:0,他引:1       下载免费PDF全文
刘衍珩  张婧  王健 《电子学报》2012,40(2):319-326
 移动自组网依靠多点协作完成路由任务,可信的路由协议需要节点之间建立一定的信任关系,但大多数信任路由模型只追求路由的信任性而忽略了健壮性.本文基于ANTHOCNET算法,设计了兼顾信任性和健壮性的TrANTHOCNET算法.引入模糊Petri网的形式化推理算法处理节点之间的不确定关系,并利用位置信息对信息素实时更新以提高路由健壮性.实验结果表明TrANTHOCNET较ANTHOCNET、AODV和T-AODV均表现出较强的抵抗恶意节点攻击的能力,在路由性能方面也验证了本算法的有效性.  相似文献   

9.
为提高移动自组织网络(mobile ad hoc network,MANET)路由查询效率,通过对P2P(peer-to-peer)网络与MANET的交叉研究,在DSR协议基础上引入Chord算法,提出双向路由模型BPDSR.BPDSR双向路由发现算法和路由资源共享算法,降低了查询复杂度,减少了路由失效和绕路问题.通过BPDSR算法性能分析和NS--2仿真实验表明,BPDSR路由模型的路由效率明显提高.  相似文献   

10.
针对多维矢量计算多约束服务质量路由出现实际传输路径与源节点期望路径并非一致问题,研究提出矢量映射方式的多约束服务质量路由计算方法。通过数学方法和物理概念相结合的方式,从原理上阐述了新算法矢量映射的合理性,并通过算例和仿真实验方式验证,新算法只需一次性计算就可以获得源节点到各节点保持路径一致的路由。  相似文献   

11.
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.  相似文献   

12.
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.  相似文献   

13.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.  相似文献   

14.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.  相似文献   

15.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.  相似文献   

16.
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.  相似文献   

17.
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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.  相似文献   

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