一种基于拓扑约束的多核跟踪算法

针对视觉跟踪中常见的目标部分遮挡和尺度变化问题,提出了一种基于拓扑约束的多核跟踪算法.首先,提取满足空间分布的位于目标与背景所在边界的Harris角点作为多核跟踪器的中心,然后,采用拓扑约束对多个跟踪结果进行优化,选取跟踪性能好的核跟踪器,构造仿射变换模型,进而得到最终跟踪结果和目标尺度变化信息.实验结果表明,本文算法能对目标进行准确跟踪,并能有效地处理目标的部分遮挡和尺度变化问题.     

一种基于相互作用多模型的目标跟踪方法及应用

首先，对传统的KLM滤波器及在跟踪机动目标的缺点和不足作了介绍，然后介绍强跟踪滤波及相互作用的多模型滤波器，采用相互作用的多模型滤波器对机动性很大的目标进行跟踪，分析IMM算法在机动目标跟踪中的优势。最后，采用部队的实际数据进行仿真，对它们的跟踪效果做了比较。     

一种新的机动目标模型及其自适应跟踪算法

在当前统计模型的基础上,结合实时输入估计算法(Feng xinxi等,1996)的思想,提出了一种新的机动目标模型,并利用其方差调整关系建立了自适应跟踪算法。大量仿真结果表明该模型能够准确描述目标的各种机动情况,跟踪算法具有良好的跟踪性能,具有实际应用价值。     

改进质心跟踪算法在实时空中目标跟踪中的应用研究

针对光电探测跟踪系统的应用,分析低空运动目标在空天背景中电视成像的特点以及常见背景成像特点。提出该场景下检测区域中点的表示方式,并以此为权重,在TMS320DM8168Davinci平台中实现实时加权质心跟踪算法。实验证明,该方法能够在嵌入式平台实现低空运动目标实时跟踪。     

一种解决遮挡问题的跟踪方法

针对图像跟踪领域中因遮挡产生的漂移问题,提出一种基于直方图比的背景加权的Mean Shift算法和Kalman预测滤波器融合的方法。本文方法通过改进目标模型来优化Bhattacharyya系数值,增大目标正常跟踪状态下和遮挡状态下Bhattacharyya系数的差值,提高遮挡判定的有效性,进而提高遮挡时的跟踪性能。通过实验证明,基于直方图比的背景加权的Mean Shift算法和Kalman预测滤波器融合的方法可有效解决遮挡跟踪问题。     

一种跳频信号实时跟踪与参数估计方法

现有的跳频信号处理方法往往需要积累足够长的样本数据,缺乏实时快速运算的能力,无法处理高速跳频信号。在小样本条件下提出一种跳频信号实时跟踪和参数估计方法。根据跳频信号的频域稀疏性建立信号模型,引入稀疏贝叶斯学习(SBL)算法解决多观测向量(MMV)信号重构问题。在构建新的判决统计量基础上,推导一种保持恒虚警概率的跳变时刻检测方法,设计滑动策略实现跳频信号的实时跟踪。分别利用几何重心法和最小二乘法估计每跳(hop)的载波频率和来波方向(DOA)。实验证明,新方法在低信噪比(SNR)下具有更低的虚警概率,参数估计精确度得到明显提升。     

一种新的步进自动跟踪方法

本文首先介绍了步进自动跟踪的两种常用方式及其所面临的问题,在此基础上建立了基于梯度步进的最佳路径搜索方法.仿真表明这种基于梯度步进的算法,在不影响精度的条件下,运算简单,减少了步进次数.     

一种门限实时自适应的小目标跟踪处理方法

分析了跟踪雷达在对小目标检测和跟踪时采用中心门限固定方法存在的缺陷,提出了一种中心门限实时自适应变化的小目标跟踪处理方法,该方法能够有效地消除目标背景杂波强度起伏较大时对小目标捕获和跟踪的影响,提高了复杂的杂波背景下对掠海小目标的快速捕获和稳定跟踪能力.     

一种基于异步传感器网络的空间目标分布式跟踪方法

为解决传感器网络在空间目标分布式跟踪过程中的异步采样及通信延迟问题,该文提出一种异步分布式信息滤波算法(ADIF)。首先,局部传感器与相邻节点之间以一定的拓扑结构传递带采样时标的局部状态信息和量测信息,然后将收到的异步信息按时间排序,使用ADIF算法进行计算,分别对目标状态进行估计。该方法实现简单,传感器间通信的次数少,支持网络拓扑的实时变化,适用于空间目标监测中的多目标跟踪问题。该文分别对空间单目标、多目标跟踪进行了仿真,结果表明算法可以有效解决异步传感器滤波问题,分布式滤波精度一致逼近于集中式结果。

     

An efficient fault-tolerant distributed channel allocation algorithm for cellular networks

A channel allocation algorithm in a cellular network consists of two parts: a channel acquisition algorithm and a channel selection algorithm. Some of the previous works in this field focused on centralized approaches to allocating channels. But, centralized approaches are neither scalable nor reliable. Recently, distributed dynamic channel allocation algorithms have been proposed, and they have gained a lot of attention due to their high reliability and scalability. But, in most of the algorithms, the cell that wants to borrow a channel has to wait for replies from all its interference neighbors and, hence, is not fault-tolerant. In this paper, we propose a new algorithm that is fault-tolerant and makes full use of the available channels. It can tolerate the failure of mobile nodes as well as static nodes without any significant degradation in service.     

An algorithm for optimal assignment of a wavelength in a tree topology and its application in WDM networks

In this paper, we present a polynomial time algorithm that gives an optimal solution to the routing and wavelength assignment (RWA) problem in a tree topology. One of the major design issues in wavelength-division multiplexed networks is the assignment of the limited number of wavelengths among network stations so that greater capacity can be achieved. The problem of RWA is known to be NP-hard problem. Many researchers have tackled the problem of RWA with a number of efficient heuristic algorithms. This paper presents an algorithm that optimally assigns a single wavelength to maximize one-hop traffic in a tree topology. The algorithm uses dynamic programming and is shown to be optimal with a time complexity of O(N/sup 4/). We also propose a heuristic scheme to use our optimal algorithm for wavelength assignment in a general graph. The heuristic works on the tree subgraphs of a given graph and the remaining spare wavelengths can be assigned with an existing RWA policy.     

An efficient multitarget tracking algorithm for car applications

A new and efficient tracking algorithm for vehicle collision warning and collision avoidance systems using car radar is proposed. The target-to-measurement data association is accomplished using the decision logic algorithm based on order statistics. The simulation and experimental results are presented to demonstrate its performance.     

An efficient topology reconfiguration algorithm for high speed connection-oriented LANs

This paper deals with the design and performance issues of a protocol, proposed for dynamic topology reconfiguration in high-speed connection-oriented local area networks (LANs). A distributed reconfiguration algorithm is introduced where each network node maintains the minimum-hop-tree connectivity information, corresponding to all the physically reachable network interfaces within the local subnetwork. An incremental and adaptive tree-maintenance strategy is designed for keeping a reconfiguration process isolated from the unaffected parts of the network. A call-by-call routing algorithm, working on top of this reconfiguration protocol, is also proposed with multiple heuristics for optimizing the end-to-end connection hop-count and network load distribution. Simulation results illustrating the correctness and performance of these protocols are included in this paper. Issues regarding a prototype implementation of the presented protocols are also discussed. © 1997 John Wiley & Sons, Ltd.     

Efficient distributed address assignment algorithm based on topology maintenance in ZigBee networks

Adopting the borrowed address algorithm can decrease the orphan nodes in ZigBee networks that use distributed address assignment mechanism （DAAM）. The existing borrowed address algorithms can increase the success rate of address assignment, but they have defects such as greater cost of overhead and time in founding network caused by breaking topology. To solve such problems, we propose an more efficient distributed borrowed address assignment algorithm based on topology maintenance （A2BTM） that has a topology maintenance function. It borrows address firstly from the offspring nodes in the same branch for the orphan nodes and replies distributed the request of the borrowed address message immediately, to maintain the network topology and decrease the overhead and time spent on the mechanism of borrowed address. Theoretical and simulation analyses manifest that AZBTM algorithm outperforms DAAM and its improved algorithms in terms of the overhead and time spent in founding network, on the premise of keeping a higher success rate of address assignment. Furthermore, A2BTM can lessen the influence from detour phenomenon efficiently.     

An efficient distributed orientation algorithm (Corresp.)

An algorithm for constructing and maintaining full information on the structure of a communication network is presented. The algorithm uses distributed computation. It can be used as an information-gathering step, to be followed by special-purpose algorithms which are to be executed within the nodes, without any additional communication. The load of the lines of the network is measured and shown to be better than any known algorithm for determining connectivity, suggesting shortest path, routing, etc., when the number of topological changes is big enough. It is shown that the network will recover in finite time from a finite number of topological changes in the network. Other, more powerful, recovery criteria are also given.     

An efficient dynamic multicast traffic-grooming algorithm for WDM networks

With the growth of multi-granularity multicast applications, there comes into being a huge gap between the bandwidth of a wavelength provided and a multicast traffic required in the wavelength division multiplexing (WDM) networks. The dynamic multicast traffic-grooming is an effective way for WDM networks to improve the wavelength utilization and decrease the traffic blocking probability. A novel switching node architecture with the multicast switching matrix and traffic-grooming fabric is studied in the paper. Then, an efficient dynamic multicast traffic-grooming algorithm is proposed for the architecture. According to the ratio of network available grooming port number to network transceiver number, the proposed algorithm estimates whether the traffic-grooming port is a scarce resource for input traffic and chooses the appropriate grooming strategy. If the traffic-grooming port is scarce, the minimized use grooming port strategy is designed for the coming traffic. On the contrary, the minimized use node transceiver strategy is applied for the coming traffic. Simulation results show that the proposed algorithm can groom traffic efficiently with low blocking probability and high network throughput constraint by limiting number of node transceivers and grooming ports.     

A distributed algorithm for energy efficient and fault tolerant routing in wireless sensor networks

Wireless Networks - Energy conservation and fault tolerance are the most two important challenging issues for the development of large scale wireless sensor networks (WSNs). Failure of cluster...     

Active networks for efficient distributed network management

The emerging next generation of routers exhibit both high performance and rich functionality, such as support for virtual private networks and QoS. To achieve this, per-flow queuing and fast IP filtering are incorporated into the router hardware. The management of a network comprising such devices and efficient use of the new functionality introduce new challenges. A truly distributed network management system is an attractive candidate to address these challenges. We describe how active network techniques can be used to allow fast and easy deployment of distributed network management applications in IP networks. We describe a prototype system where legacy routers are enhanced with an adjunct active engine, which enables the safe execution and rapid deployment of new distributed management applications in the network layer. This system can gradually be integrated in today's IP network, and allows smooth migration from IP to programmable networks. This is done with an emphasis on efficient use of network resources, which is somewhat obscure by many of today's high-level solutions     

An energy efficient clustering routing algorithm for wireless sensor networks

~~An energy efficient clustering routing algorithm for wireless sensor networks1. Mainwaring A, Polastre J, Szewczyk R, et al. Wireless sensor networks for habitat monitoring. Proceedings of the ACM International Workshop on Wireless Sensor Networks and A…