基于多属性分类的雷达目标跟踪算法

传统目标跟踪算法无法有效利用目标的属性信息,而已有的基于PN学习的雷达目标跟踪算法获取目标属性信息过少,在杂波更为复杂的实际环境中仍然存在滤波能力不足的情形。针对这一问题,提出基于SVM多属性分类器的目标跟踪滤波算法。该算法在原有的PN学习算法基础上,扩宽了系统获取雷达数据信息的维度。这些数据更好地反映了目标和杂波的特征,使得雷达识别杂波的能力增强。仿真实验表明:该算法在强杂波环境下有效地提升了目标跟踪的精度。     

多传感器多目标跟踪的粒子PHD滤波算法

针对单传感器跟踪系统的缺陷,提出了基于粒子概率假设密度(PHD)滤波的多传感器多目标跟踪算法.这种算法不仅避免了多传感器多目标跟踪的数据关联问题,而且在漏检、目标密集、航迹交叉、小范围内目标数多的杂波环境下能够稳定、精确地估计目标状态和目标数.仿真实验比较了单传感器粒子PHD滤波与多传感器的粒子PHD滤波的跟踪性能,验证了该方法的跟踪性能和精度.     

基于自适应遗传PHD滤波的多群目标跟踪方法

针对标准的概率假设密度（PHD）滤波算法在杂波环境下对群目标跟踪误差较大的问题,提出一种基于自适应遗传PHD滤波的多群目标跟踪方法。该方法在PHD粒子滤波的基础上,利用选择概率减少了新生粒子的数量。为了有效抽取交叉粒子,在时间更新阶段引入当前量测与群目标间的马氏距离。为了提高预测粒子的鲁棒性,推导出自适应交叉与变异操作方案。仿真实验表明,所提出的方法能有效跟踪杂波环境下的多群目标,具有目标总数估计稳定、运动状态估计准确的特点。     

多目标跟踪中一种改进的高斯混合PHD滤波算法

高斯混合概率假设密度（GM-PHD）滤波是一种杂波环境下多目标跟踪问题算法,针对算法中存在的目标漏检和距离相近时精度下降的问题,提出一种改进的高斯混合PHD滤波算法。该算法在高斯混合框架下通过修正PHD递归方程,有效地解决了漏检引起的有用信息丢失问题;利用权值判断高斯分量是否用于提取目标状态,避免了具有较高权值的高斯分量合并在一起,从而改善目标相互接近时的跟踪性能。仿真实验表明,改进算法在滤波精度和目标数估计方面均优于传统的GM-PHD算法。     

高精度RBP-模糊推理复合学习系统

该文提出了高精度RBP-模糊推理复合学习系统.系统主要由基于鲁棒估计的鲁棒BP 学习环节和基于混合合成推理的模糊推理环节构成.该学习系统的主要特点是可由鲁棒BP 算法和min-max,max-min模糊推理算法简单地实现.最后通过在目标跟踪问题中应用结 果,表示了该算法的高精度和鲁棒性.     

基于M估计的非线性鲁棒检测卡尔曼滤波算法

针对传统鲁棒非线性滤波在观测噪声为非高斯强干扰噪声情况下,滤波性能下降的问题,提出一种利用卡方检测法预判断的非线性鲁棒检测滤波算法。该算法通过卡方检测设置门限,剔除突变野值,利用M估计修正量测更新。仿真实验对比了几种典型非线性滤波方法在不同观测噪声环境下的性能。所提算法在非高斯强干扰噪声情况下,比传统鲁棒滤波算法估计精度平均提高了25.5%;估计方差平均减少了18.3%。实验结果表明:所提算法可以抑制观测量非高斯强干扰噪声的影响,提高滤波精度及稳定性。     

多目标联合检测与估计的误差界

在随机有限集框架下提出了当杂波和漏检存在时基于最优子模式分配距离的多目标联合检测与估计(JDE) 误差界. 此处的JDE 是指同时估计目标个数和存活目标状态. 算例1 展示了该误差界随传感器检测概率和杂波密度的变化趋势; 算例2 利用多假设跟踪, 概率假设密度(PHD) 和势PHD 滤波器对该误差界的有效性进行了验证.

     

一种改进的TLD动态手势跟踪算法

针对目前动态手势跟踪算法TLD(跟踪-学习-检测)算法在手势目标遮挡后易出现跟踪漂移的不足,提出了一种改进的TLD动态手势跟踪算法.在跟踪器跟踪成功后,引入遮挡窗的方法进行手势目标遮挡的判定.若出现部分遮挡,则由TLD学习器处理;若出现严重遮挡,则在TLD的跟踪器中加入卡尔曼滤波器来预测估计当前帧中手势可能存在的区域,缩小跟踪器的搜索范围,提高跟踪器的处理速度;并在TLD检测器中加入基于马尔可夫模型的方向预测器,缩小检测器的检测范围,增强检测器对相似手势轨迹的判别能力.实验结果证明,改进后的TLD算法在不同的实验环境下均有较强的鲁棒性,能够快速准确地进行动态手势运动轨迹的跟踪,并且改善了手势目标遮挡后易出现跟踪漂移的问题.     

恒虚警率PDAF的弱点状目标跟踪技术性能分析

PDAF与PDAF-AI算法广泛应用于雷达目标检测与微弱点状目标跟踪领域,两者不同之处在于PDAF-AI算法在利用目标位置、运动速率的基础上多加了目标的亮度信息通过Kalman滤波器去估计目标下一时刻的状态。PDAF-AI改变了传统PDAF算法忽略目标亮度信息的不足,它应具有更好的跟踪性能。通过对这两种算法跟踪性能的对比分析研究：带亮度的概率数据关联滤波器技术PDAF-AI总体上比传统的PDAF技术具有更好的实时跟踪性能,然而在强杂波或跟踪区域存在高亮杂波的情况下PDAF-AI的跟踪性能可能会有所下降。     

结合Boosting方法与SVM的多核学习跟踪算法

针对传统算法在外界环境及目标运动导致外形变化的影响下跟踪效果不稳定的问题,提出一种鲁棒的多核学习跟踪算法,将Boosting提升方法引入到多核学习框架中,用比传统多核学习算法更少的样本训练,构建出基于互补性特征集和核函数集的弱分类器池,从中将多个单核的弱分类器组合出一个多核的强分类器,从而在出现较强背景干扰、目标被遮挡的情况下仍能正确地对候选图块中的背景和目标进行分类。对不同视频序列的测试结果表明,与同样采用Boosting方法的OAB算法及近年跟踪精度高的LOT算法相比,该算法能够在复杂环境下更准确地跟踪到目标。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.     

Call for Papers The 6^th International Conference on Grid and Cooperative Computing

Recent years have seen rapid advances in various grid-related technologies, middleware, and applications. The GCC conference has become one of the largest scientific events worldwide in grid and cooperative computing. The 6th international conference on grid and cooperative computing (GCC2007) Sponsored by China Computer Federation (CCF),Institute of Computing Technology, Chinese Academy of Sciences (ICT) and Xinjiang University ,and in Cooperation with IEEE Computer Soceity ,is to be held from August 16 to 18, 2007 in Urumchi, Xinjiang, China.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and     

Editorial:Brain-machine interface(BMI) and cyborg intelligence

正Brain-machine interfaces(BMIs)aim at building a direct communication pathway between the brain and an external device,and represent an area of research where significant progress has been made during the past decade.Based on BMIs,mind information can be read out by neural signals to control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate     

SCIENCE CHINA Information Sciences SUBJECT INDEX TO VOLUME 57(2014)

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