Distributed Borrowing Addressing Scheme for ZigBee/IEEE 802.15.4 Wireless Sensor Networks

This paper proposes a distributed borrowing addressing (DIBA) scheme to solve problems of failure in address assignments resulting from limited tree depth and width when the distributed address assignment mechanism is used in a ZigBee/IEEE 802.15.4 wireless sensor network. DIBA is a method of borrowing addresses from neighbor nodes for newly entering nodes and assigning the borrowed addresses. Its network or sensing coverage can increase with almost the same overhead as the existing method. DIBA is a simple and lightweight means of addressing and routing, making it suitable for wireless sensor networks. Simulations showed that DIBA is a distributed addressing scheme with consistently excellent performance.     

移动网络中数据业务关键性能指标KPI探讨

移动网络的性能评估是网络规划和优化建设的前提，数据业务的迅速发展为移动网络的性能评估提出新的课题，当前评价数据业务网络的关键性能指标主要有吞吐量、时延等，从网络的容量和质量角度出发提出每用户平均吞吐量和网络资源利用率两个关键性能指标，并分别进行理论分析，为数据业务网络的性能评估提供参考依据。     

一种Ad—hoc密钥维护优化方案

Ad-hoc网络节点之间的无线连接越多，网络通信跳数相对越少，但网络需要的密钥量越大，加重了密钥维护的负担，因此在通信跳数可接受的情况下应该尽量减少密钥量。定义了网络付出的代价，用来描述通信跳数和密钥量。以网络付出的代价最小为原则，设计了一种简单的密钥维护优化方案。将方案应用于一个Ad-hoc场景，推算结果表明该方案对密钥维护的优化是有效的。     

Different Epidemic Models on Complex Networks

Models for diseases spreading are not just limited to SIS or SIR. For instance, for the spreading of AIDS/HIV, the susceptible individuals can be classified into different cases according to their immunity, and similarly, the infected individuals can be sorted into different classes according to their infectivity. Moreover, some diseases may develop through several stages. Many authors have shown that the individuals＇ relation can be viewed as a complex network. So in this paper, in order to better explain the dynamical behavior of epidemics, we consider different epidemic models on complex networks, and obtain the epidemic threshold for each ease. Finally, we present numerical simulations for each case to verify our results.     

A concurrent two-layer restoration scheme for GMPLS WDM networks

Next generation backbone networks will likely consist of IP routers as well as optical cross connects (OXCs) and will deploy an optical control plane protocol. Generalized Multi Protocol Label Switching (GMPLS) has been proposed as the candidate of choice for the control plane. Optical fibers may carry large volumes of traffic and therefore adequate mechanisms must exist to enable the network to automatically recover from failures of fiber. In mission critical networks survivability becomes very important. We investigate the problem of autonomous recovery in such networks. The literature contains work in this area that investigates the problem of multilayer recovery. Such recovery had only been sequential in the sense that the published work recovers first in the optical domain, assuming the availability of redundant resources, and then proceeds to recover packet label switched paths. We report a recovery procedure for recovering packet label switch paths (packet LSPs) and lambda label switch paths (λLSP) concurrently. We have conducted an OPNET-based simulation study that compares the performance of the concurrent scheme with the previously published sequential two-layer recovery scheme. The study shows that the concurrent two-layer recovery scheme performs as much as forty-four percent faster than the sequential two-layer recovery scheme.     

聚合度在地域通信网关键节点识别中的应用

介绍了地域通信网的概念,分析了研究地域通信网关键节点识别的重要性。从网络的拓扑结构出发,给出了两种聚合度的定义方法,并把这两种定义方法应用到关键节点识别中,通过实例对两种方法进行分析对比它们的优缺点,得出方法二更适用于地域通信网这样复杂网络的关键节点识别中。     

Bibliography on Nullors and Their Applications in Circuit Analysis, Synthesis and Design

A bibliography on research work related to nullors and their applications in circuit analysis, synthesis and design, covering the period 1961–2000, is given.     

前向神经网络的神经元分层逐个线性优化快速学习算法

本文提出了一种新的前向神经网络快速分层学习算法.在此学习算法中,其优化策略为对输出层和隐层神经元的连接权值交替优化.对输出层权值优化算法采用基于广义逆的最小二乘递推算法,对隐层神经元的连接权值采取则对每个神经元逐个进行优化,而且采用正交变换加快每一步学习的计算速度和提高算法的数值稳定性.当学习过程停滞时采用随机扰动的方法摆脱过早收敛.数值实验表明,与BP动量因子法、牛顿型方法和现有的分层优化算法相比,新算法不仅学习速度快学习时间短,而且当网络规模增大时仍然比较有效.     

基于应用的实时网络管理

本文针对指挥信息系统实时网络管理需求，通过对现有网管系统组成、网络管理技术和功能的分析，提出指挥信息系统基于应用的实时网络管理设想。     

学校非线性编辑教学环境中存在的问题及其对策研究

论述目前学校非线性编辑教学环境中存在的问题,从教学需求角度分析解决问题的思路,并提出软硬件相结合构建多功能网络非线性编辑教学环境的应对策略。