Cellular/WLAN融合网络中基于优先级的动态负载传递算法

针对蜂窝网和无线局域网(WLAN)的融合网络,提出一种基于优先级的动态负载传递(PDLT)算法.呼叫接入控制的动态垂直切换由整个网络状态和业务特性以及终端位置信息联合触发.当蜂窝网络或WLAN中无可用带宽资源时,该算法能够将重叠覆盖区域中新的语音或者数据呼叫传递到尚有带宽资源的网络;同时,动态计算网络带宽资源占用情况,...     

Automatic target tracking on multi-resolution terrain

INTRODUCTION In this paper, we propose an automatic target tracking method in our real-time simulation and animation system of large-scale terrain field. Our system supplies autonomous guidance, navigation and control of moving objects, in order to efficiently perform related challenging missions in manufacture, entertainment, and other real-world applications. Our goal is to deploy a large number of moving vehicles upon a large-scale virtual terrain (essentially a 2D curved terrain surfa…     

多种网络业务并存的IEDF算法研究

文章以EDF算法为基础,提出一种改进的调度算法IEDF。在IEDF中,提出一种新的带宽调度策略,并在3种具体情况下进行业务流调度过程分析。同时,在SIM环境下进行仿真实验,仿真结果表明,和原EDF算法相比,IEDF算法有效保证了带宽,降低了时延,提升了Qos。     

Bandwidth allocation algorithm for aggregated tree in optical networks

Wavelength and bandwidth allocation is important for multicast communication in optical networks. In this paper, a new method based on scheduling theory is proposed. The proposed method formulates wavelength bandwidth capacity as a large rectangle and these multicast stream bandwidth requirements as small rectangles. It treats the wavelength and bandwidth allocation question as a rectangle packing problem. The proposed algorithm solves the problem by taking quasi-human strategy with Euclidian distance. It is an effective heuristic algorithm to quickly solve multicast stream bandwidth allocation problem in optical networks by theoretic analysis. Further simulation experiments show the bandwidth allocation algorithm can increase network utilization and have a good fairness performance for unicast stream and multicast stream in optical networks. The results indicate the effectiveness of the algorithm.     

Algorithm for Delay-Constrained Minimal Cost Group Multicasting

Group multicast routing algorithms satisfying quality of service requirements of real-time applications are essential for high-speed networks. A heuristic algorithm was presented for group multicast routing with bandwidth and delay constrained. A new metric was designed as a function of available bandwidth and delay of link, And source-specific routing trees for each member were generated in the algorithm by using the metric, which satisfy member＇s bandwidth and end-to-end delay requirements. Simulations over random network were carried out to compare the performance of the proposed algorithm with that from literature. Experimental results show that the algorithm performs better in terms of network cost and ability in constructing feasible multicast trees for group members. Moreover,the algorithm can avoid link blocking and enhance the network behavior efficiently.     

Path Planning and Tracking for Vehicle Parallel Parking Based on Preview BP Neural Network PID Controller

In order to diminish the impacts of external disturbance such as parking speed fluctuation and model uncertainty existing in steering kinematics, this paper presents a parallel path tracking method for vehicle based on preview back propagation(BP) neural network PID controller. The forward BP neural network can adjust the parameters of PID controller in real time. The preview time is optimized by considering path curvature, change in curvature and road boundaries. A fuzzy controller considering barriers and different road conditions is built to select the starting position. In addition, a kind of path planning technology satisfying the requirement of obstacle avoidance is introduced. In order to solve the problem of discontinuous curvature, cubic B spline curve is used for curve fitting. The simulation results and real vehicle tests validate the effectiveness of the proposed path planning and tracking methods.     

A novel algorithm for Ethernet-passive-optical-network dynamic bandwidth allocation based on threshold

The Ethernet passive optical network (EPON) is the next generation of broad-band network technique. A crucial issue in EPONs is the sharing of uplink bandwidth among optical network units (ONUs). This article provides a novel dynamic bandwidth allocation algorithm, i.e. threshold dynamic bandwidth allocation (TDBA), which is based on adaptive threshold, to increase resource utilization. The algorithm uses ONU data-transmitting rate to adjust optical line terminal (OLT) receiving data threshold from an ONU. Simulation results show that this algorithm can decrease average packet delay and increase network throughput in a 10G EPON system.     

Streaming and congestion control using scalable video coding based on H.264/AVC

INTRODUCTION Streaming of multimedia data over the Internet has rapidly increased in recent years. All commercial applications and most research in video streaming use conventional hybrid video coding. To adapt the data transmission rate on the server to the varying bandwidth caused by congestion in the Internet or to different available bandwidths of different clients, the simulcast solution is widely applied (Balk et al., 2003; Feamster et al., 2001; Schierl and Wiegand, 2004). A larg…     

Ad Hoc网络中最大最小公平性算法的改进

Ad Hoc网络的信道资源非常有限,且相邻节点之间竞争网络资源,公平有效的分配带宽成为Ad Hoc网络的重要研究方向。本文在已有的最大最小公平算法基础上,采用加权的最大群算法,并利用节点的代价值作为权值进行调节,保证了带宽的公平分配,而且有效的提高了网络资源的利用率。     

含公布电源配电网可靠性的评估方案研究

在原有配电网引入分布式电源的情况下,提出一种基于应用改进最小路法结合可靠性指标求解评估含分布式电源distributed generation（DG）的配电网可靠性评估方案。以IEEE-RBTS Bus6 系统为例进行不同方案的仿真。仿真结果表明,所提出的可靠性评估模型可以明显地改善配电网系统对用户提供电能的可靠性。     

基于多出口链路网络负载平衡模型研究

基于固定多出口链路网络,根据多目标优化理论方法,提出一种分割调度模型作为负载平衡的优化方法。动态选择最优路径,得到相应的网络链路多目标优化解。推导出了基于多约束条件下的循环择优路径算法。实验表明,算法适用于多链路各种负载下的流量优化,有效解决了宽带网络的大量用户接入及负载均衡问题。     

无线ad hoc网络最小均方负载均衡路由算法

Routing algorithm is a challenge for a mobile ad hoc network (MANET), but current routing protocols for MANETsconsider the path with minimum number of hops as the optimal path to a given destination. This strategy does not balancethe traffic load over a MANET, and may result in some disadvantages such as creating congested area, depleting power fasterand enlarging time delay in the nodes with heavy duties. In this paper, we propose a routing scheme that balances the loadover the network by selecting a path based on its mean load-square, the proposed routing metric can reflect not only the loadof the path, but also the load distribution along the path. Simulation results show effectiveness of this routing scheme onbalancing the load over all nodes in the network.     

基于KPKM算法的动目标检测与跟踪

针对均值偏移算法在跟踪目标发生形变和遮挡时丢失问题,提出了一种自适应目标检测、核函数带宽可变、Kalman滤波预测和重心轨迹跟踪的改进均值偏移算法（KPKM）。该算法利用目标检测中得到的外接矩形和重心作为均值偏移算法的初值,用改进的Kalman滤波器预测目标运动趋势,使本算法能沿着梯度方向快速收敛到目标中心。实验和仿真结果表明,该方法实现了在复杂场景下,对运动目标的精确检测和准确跟踪。     

Control method for exoskeleton ankle with surface electromyography signals

This paper is concerned with a control method for an exoskeleton ankle with electromyography (EMG) signals. The EMG signals of human ankle and the exoskeleton ankle are introduced. Then a control method is proposed to control the exoskeleton ankle using the EMG signals. The feed-forward neural network model applied here is composed of four layers and uses the back-propagation training algorithm. The output signals from neural network are processed by the wavelet transform. Finally the control orders generated from the output signals are passed to the motor controller and drive the exoskeleton to move. Through experiments, the equality of neural network prediction of ankle movement is evaluated by giving the correlation coefficient. It is shown from the experimental results that the proposed method can accurately control the movement of ankle joint. Project supported by the National High-Tech R&D Program (Grant No.2006AA04Z224), the Innovation Program of Shanghai Municipal Education Commission (Grant No.08ZZ48), and the Shanghai Leading Academic Discipline Project (Grant No.Y0102)     

基于SLSD道路网络模型的最优路径算法

提出了基于单线单向（SLSD）道路网络的最优路径算法.不同于传统网络,在SLSD网络中,路元素被抽象成网络的节点,且都是单向单线的;而道路节点被抽象成网络的链接.该网络模型可以很好地表述拐弯限制、回路以及多条道路存在于2个路口等只有超图模型才能很好表示的真实路网情形.基于此网络模型,给出了相关的最优路径算法,并且证明了将超图转化为SLSD道路网络后,A＊及Diskstra算法可以不加修改直接用于计算任何真实路网的最优路径.最后,结合新加坡道路网络数据,给出了一个预先计算的两步法最优路径算法及其计算结果,验证了所提出的模型和算法.     

边缘节点缓存替换策略研究

缓存替换机制是内容中心网络研究的重点,在解决网络时延与网络带宽拥堵等问题中发挥着重要作用。针对目前边缘侧量节点设备缓存空间的有限性,提出一种基于猴群算法的优化方案。该方案可合理地对边缘设备缓存内容进行置换,有效提高边缘量设备请求命中率。通过在猴群算法的猴群爬过程中引入文件流行度等引导因子、在望过程中改进猴群视野范围等方法找到最优解。仿真实验结果显示了不同大小的边缘设备缓存空间请求命中率。与传统算法相比,该方案可有效提高请求命中率。     

Incremental min-period retiming algorithm for FPGA synthesis based on influence of fan-outs

An improved linear-time retiming algorithm is proposed to incrementally optimize the clock period,especially considering the influence of the in-out degree of the critical combinational elements.Firstly,the critical elements are selected from all the critical combinational elements to retime.Secondly,for the nodes that cannot be performed with such retiming,register sharing is implemented while the path delay is kept unchanged.The incremental algorithm can be applied with the technology mapping to minimize the critical path delay and obtain fewer registers in the retimed circuit with the near-optimal clock period.Compared with Singh’s incremental algorithm,experiments show that the proposed algorithm can reduce the flip-flop count by 11% and look-up table(LUT) count by 5% while improving the minimum clock period by 6%.The runtime is also reduced by 9% of the design flow.     

基于PCNN的交通系统路径优化算法研究

分析了脉冲耦合神经网络的路径寻优原理,针对交通诱导系统的要求提出了脉冲耦合神经网络的简化方法和应用模型,给出了基于脉冲耦合神经网络简化模型的最短路径的算法.通过算例,显示出其具有较高的寻优效率和收敛性.     

基于Diffserv模型的队列调度加权优化算法

在Diffserv模型的基础上提出了一种基于WRR调度算法的加权优化算法，给出了该算法的实现方法．加权优化算法是根据网络中各业务数据的实际流量动态的调整其对应的权值。还能根据该节点的实际负载状况，提供动态的带宽分配。     

An optimal quality adaptation mechanism for end-to-end FGS video FGS video transmission

In this paper, we propose a novel optimal quality adaptation algorithm for MPEG-4 fine granular scalability (FGS) stream over wired network. Our algorithm can maximize perceptual video quality by minimizing video quality variation and increasing available bandwidth usage rate. Under the condition that the whole bandwidth evolution is known, we design an optimal algorithm to select layer. When the knowledge of future bandwidth is not available, we also develop an online algorithm based on the optimal algorithm. Simulation showed that both optimal algorithm and online algorithm can offer smoothed video quality evolution.