传输网络波分化后对于维护的变化

随着业务逐渐IP化,传输网络正在由原来传统的SDH＋WDM向以WDM为主变化。但是相对目前传统WDM对光波长级的传送,SDH层在故障判断与定位、业务调度、小颗粒业务传送以及保护方式方面有一定的优势与便利性,因此随着传输网络逐渐波分化,对于传输网络的维护也与传纯的SDH＋WDM有所璺别。     

基于萤火虫算法的层间网络编码优化

在异构网络中,分层网络编码不仅可以解决信宿的不同接收速率要求,也可以提高网络吞吐量。其中,层间网络编码与层内网络编码相比可以获得更高的带宽利用率,因此层间网络编码的优化问题成为提高网络性能的一个关键问题。本文考虑单信源多信宿的网络,首先分析了层间网络编码模型的数学规划,再利用改进萤火虫算法(FA)的快速搜索能力实现链路的分层类型和层速率的优化分配,以此实现了网络吞吐量的提高。仿真结果证明,与仅优化链路分层类型的算法相比,此优化算法以较少的迭代次数实现优化并获得高吞吐量。     

基于FDMA系统的两跳中继网络的资源分配

首先介绍了一种可用于两跳中继网络的时分模式帧结构,然后基于该帧结构提出了一种资源分配算法.该算法包括两个步骤:第一个步骤是第一个时隙上的动态资源分配,第二个步骤是基站与中继站之间的最优化功率分配.两跳中继网络中下行存在三种链路:"基站-中继"链路、"基站-用户"链路和"中继-用户"链路,在系统资源有限的条件下,通过所提算法为这三种链路分配相应的带宽和功率,可以使得系统的吞吐量最大.仿真结果表明所提算法能够有效地提高系统的吞吐量.     

基于MLAG的三层码分多粒度光交换系统的性能研究

在波长交换的基础上,引入光码交换,并基于光码分复用(OCDM)建立了一种三层多粒度光交叉联接(MG-OXC)系统,并给出了一种新的业务疏导算法。该体系结构能够很好地改善业务疏导,减少使用波长数量,节省消耗端口数目,因此它可以简化路由设置,优化节点业务疏导的灵活性,提高系统性能。简要介绍了三层多粒度光交换体系的结构,并在端口节省方面进行了比较。通过在多路分层辅助图表(MLAG)上对交换结构网络模型和业务疏导链路建立的分析,以及对阻塞率和吞吐量的仿真,展现了该体系的良好性能。     

一种新型IP OVER WDM城域网的节点结构

提出了一种基于波分复用（WDM）,分组交换,副载波复用和波长变换技术的新型全光城域网节点结构,网络拓扑采用环形,网络节点采用可调输出固定输入的选波原则以利于数据的多重接入,副载波复用和基于级联半导体光放大器的波长变换,实现了射频副载波路由信息与基带IP数据包的同步复用和IP数据包的透明传输。     

基于可靠性的自由空间光网络路由算法

自由空间光(FSO)网络容易受天气等因素影响造成网络中断。为了提高光网络可靠性,同时均衡网络能耗,延长网络生命周期,首先综合考虑接收光信号强度和中断概率建立可靠性模型,利用可靠性模型对直传和中继链路方式进行对比分析,获取选择直传和中继方式的距离阈值。然后针对网络能耗均衡问题,考虑节点能量进行簇头选举,提出光学中继的能耗均衡路由算法(BEC-ORM)。最后利用Matlab仿真平台求取了BEC-ORM算法选择通信方式的距离阈值,以及最佳的簇头比例。同其他算法对比分析,结果表明该算法能有效提高自由空间光网络的可靠性和能耗均衡性。     

抗毁性WDM网状光网络中的P圈快速构造算法

p圈法是抗毁性网状WDM光网络中一种十分优秀的保护算法,在p圈配置到网状光网络的过程中,圈构造算法是设计的第一步.文中提出了一种快速圈挖掘算法(FCMA),本算法基于k-最短路由算法构造最小p图,通过圈扩展算法获得更多性能优良圈,文中给了启发式算法的具体步骤.通过计算机仿真表明,该算法实现快速圈构造,性能优于其它同类算法,适合网状光网络中的p圈快速构造.     

基于多维帧映射的光网络资源描述算法

通过分析光网络资源在复杂网络资源调度中的特点,提出了波分复用(WDM)网络的一种基于多维帧映射的光网络资源描述算法.该算法的设计旨在高效、准确描述光网络拓扑资源状态信息,为对光网络资源的高效利用与快速响应奠定基础.该算法采用多维的方式描述光网络资源状态信息,采用帧模块分层次、分布式的方式呈现光网络资源状态信息,实现资源的准确发现、快速更新、高效调度.通过示例分析证明,该算法可有效缩短资源发现的响应时间,很大程度地提高资源发现的准确性,有效地提高资源调度的效率.     

基于遗传算法的层间等级网络编码优化

面向单信源异构信宿网络,研究了层间等级网络编码的编码类型优化。基于遗传算法,提出了一种最优编码类型的快速搜索方案。该方案充分考虑了信源输出链路上进行的层间等级网络编码的编码类型对整个网络传输性能的影响,将网络总吞吐量作为评价编码类型优劣的标准,设计了符合层间等级网络编码本质特性的遗传操作。实验结果表明,与分层组播网络编码和基于现有启发式算法的层间等级网络编码相比,基于本文方案实现的层间等级网络编码能够为单信源异构信宿网络获得更高的网络总吞吐量。     

IP业务传输在SDH传输网上的实现

基于TCP/IP协议的计算机网络和电话通信网络,二者各自独立,分别用于IP分组业务和64K电话业务的传输和交换。本项目可充分利用电话通信网络的SDH传输网富裕的带宽资源,传输IP分组交换业务。     

Modelling photosystem I as a complex interacting network

In this paper, we model the excitation energy transfer (EET) of photosystem I (PSI) of the common pea plant Pisum sativum as a complex interacting network. The magnitude of the link energy transfer between nodes/chromophores is computed by Forster resonant energy transfer (FRET) using the pairwise physical distances between chromophores from the PDB 5L8R (Protein Data Bank). We measure the global PSI network EET efficiency adopting well-known network theory indicators: the network efficiency (Eff) and the largest connected component (LCC). We also account the number of connected nodes/chromophores to P700 (CN), a new ad hoc measure we introduce here to indicate how many nodes in the network can actually transfer energy to the P700 reaction centre. We find that when progressively removing the weak links of lower EET, the Eff decreases, while the EET paths integrity (LCC and CN) is still preserved. This finding would show that the PSI is a resilient system owning a large window of functioning feasibility and it is completely impaired only when removing most of the network links. From the study of different types of chromophore, we propose different primary functions within the PSI system: chlorophyll a (CLA) molecules are the central nodes in the EET process, while other chromophore types have different primary functions. Furthermore, we perform nodes removal simulations to understand how the nodes/chromophores malfunctioning may affect PSI functioning. We discover that the removal of the CLA triggers the fastest decrease in the Eff, confirming that CAL is the main contributors to the high EET efficiency. Our outcomes open new perspectives of research, such comparing the PSI energy transfer efficiency of different natural and agricultural plant species and investigating the light-harvesting mechanisms of artificial photosynthesis both in plant agriculture and in the field of solar energy applications.     

Software-Defined Space-Air-Ground Integrated Network Architecture with the Multi-Layer Satellite Backbone Network

Under the background of the rapid development of ground mobile communication, the advantages of high coverage, survivability, and flexibility of satellite communication provide air support to the construction of space information network. According to the requirements of the future space information communication, a software-defined Space-Air-Ground Integrated network architecture was proposed. It consisted of layered structure satellite backbone network, deep space communication network, the stratosphere communication network and the ground network. The SpaceAir-Ground Integrated network was supported by the satellite backbone network. It provided data relay for the missions such as deep space exploration and controlled the deep-space spacecraft when needed. In addition, it safeguarded the anti-destructibility of stratospheric communication and assisted the stratosphere to supplement ground network communication. In this paper, algorithm requirements of the congestion control and routing of satellite backbone protocols for heterogeneous users’ services were proposed. The algorithm requirements of distinguishing different service objects for the deep space communication and stratospheric communication network protocols were described. Considering the realistic demand for the dynamic coverage of the satellite backbone network and node cost, the multi-layer satellite backbone network architecture was constructed. On this basis, the proposed Software-defined Space-Air-Ground Integrated network architecture could be built as a large, scalable and efficient communication network that could be integrated into space, air, and ground.     

网络时代的三大基本定律与骨干网容量的演进

文章首先分析了新时期的巨大挑战及其对网络的深远影响,特别指出了网络面临的巨大容量压力。接下来分别就主宰网络时代的三个基本定律：摩尔定律、光纤定律和迈特卡尔夫定律的内涵、影响和技术极限进行了论述。最后探讨了骨干网传输链路、传送节点和业务节点的容量演进策略。     

电磁驱动分置式斯特林制冷机综合网络模型

根据系统动力学建立了电磁驱动分置式斯特林制冷机整机的综合网络模型。该模型综合分析了电磁驱动分置式斯林特制冷机的流体网络，热声网络以及机电网络的有关研究成果，并加以完善，比较全面地反映了电磁驱动分置式斯林制冷机各个方面的动态特性，以此为基础编制的制冷机整机仿真程序，为分置式斯林特林制冷机的整机优化设计，离线调机，在线控制等行为提供了依据。     

Deterministic global optimization approach to steady-state distribution gas pipeline networks

Natural gas is normally transported through a vast network of pipelines. A pipeline network is generally established either to transmit gas at high pressure from coastal supplies to regional demand points (transmission network) or to distribute gas to consumers at low pressure from the regional demand points (distribution network). In this study, the distribution network is considered. The distribution network differs from the transmission one in a number of ways. Pipes involved in a distribution network are often much smaller and the network is simpler, having no valves, compressors or nozzles. In this paper, we propose the problem of minimizing the cost of pipelines incurred by driving the gas in a distribute non-linear network under steady-state assumptions. In particular, the decision variables include the length of the pipes’ diameter, pressure drops at each node of the network, and mass flow rate at each pipeline leg. We establish a mathematical optimization model of this problem, and then present a global approach, which is based on the GOP primal-relaxed dual decomposition method presented by Visweswaran and Floudas (Global optimization in engineering design. Kluwer book series in nonconvex optimization and its applications. Kluwer, Netherlands, 1996), to the optimization model. Finally, results from application of the approach to data from gas company are presented.     

面向对象的神经网络类库

提出一种面向对象的神经网络类库的构造方法。该类库采用面向对象的方法，集成了当前比较成熟的人工神经网络模型，充分利用了ＯＯＰ方法的继承性、封装性和多态性，便于在现有基础上派生出新的神经网络模型。该类库将被用于实现一种最新的同步振荡神经网络－ＬＥＧＩＯＮ网络。由于系统的结构性和代码的可重用性，既有利于科研工作者进行神经网络的研究，也便于工程人员的神经网络应用。     

信息网络--现代信息工程学的前沿

信息网络正在各地迅猛崛起,并以史所罕见的规模和速度生长成为世界性社会基础结构,深刻地改变着人们的生产方式、工作方式、学习方式、交往方式、生活方式和思维方式,成为工程学界以至整个社会普遍关注的集点、热点和前沿。文章旨在从理论上廓清信息网络的概念,阐明为什么信息网络对于科学技术的进步、对于世界经济和人类社会的发展能够产生如此巨大和深远的作用与影响。在此基础上,论述信息网络在现代工程学中的作用与地位,以及信息网络工程学在当前的主要研究内容和方向。     

A TWO-PHASE NETWORK DESIGN HEURISTIC FOR MINIMUM COST WATER DISTRIBUTION SYSTEMS UNDER A RELIABILITY CONSTRAINT

This paper presents a two-phase design and optimization procedure for constructing a pipe network water distribution system having a built-in degree of reliability. The first phase is comprised of an algorithm called TREESEARCH which iteratively constructs a tree pipe network. Starting with a shortest-path based tree, the procedure employs a linear programming subproblem to systematically modify this tree by adding and deleting one link at a time, with the aim of reducing the cost of the network while satisfying the flow continuity, energy balance, and pressure head requirement constraints. The second phase of the algorithm, called REDUNDANCY, is concerned with the issue of reliability. In this phase, the tree network constructed by the algorithm TREESEARCH is augmented through the addition of links so that there are at least two arc-disjoint paths from each source node to every demand node it serves. This augmentation is performed through the use of a set covering problem which recommends the links to be added, and a Hardy-Cross solver for redesigning the perturbed network to ensure feasibility, while attempting to minimize the overall design cost. The two phases are coordinated by applying algorithm REDUNDANCY to several candidate solutions presented by TREESEARCH. Two example problems from the literature, one involving a single source and the other a multiple source network, are solved using the proposed procedure. The solutions obtained have a smaller cost than those previously obtained by other researchers.     

快速以太校园网结构设计研究

目的 研究适用于切实可行的、符合校园网络技术发展的快速以太校园网络结构。方法 通过需求分析寻找网络传输瓶颈，分析相关以太网技术。结果与结论 提出一种快速以太校园网络结构，这种结构能够满足校园网信息传输需求。     

一类非对称离散Hopfieid网络的收敛性

讨论了一类特殊的非对称离散Ｈｏｐｆｉｅｌｄ网格在串行和并行两种方式下的收敛性问题。证明了该类网络在串行方式下至多经２ｎ步（ｎ为神经元个数）可收敛到平衡点；在并行方式下或者收敛到一平衡点或者进人２─圈。