基于改进Mean-Shift与自适应Kalman滤波的视频目标跟踪

提出一种改进的Mean-Shift和自适应Kalman滤波器相结合的视频运动目标跟踪算法。对选定的跟踪目标,采用三帧差和区域增长法分割目标并得到主颜色信息。在跟踪过程中,利用自适应的Kalman滤波器估计每一帧的起始迭代位置,再利用改进的Mean-Shift算法得到跟踪位置并作为测量值反馈给自适应Kalman滤波器,并引入遮挡率因子以自适应地调节Kalman估计参数。实验结果表明,该算法能对视频中的运动目标实现检测和连续跟踪,对遮挡也有较好的鲁棒性。     

结合Kalman滤波器的Mean-Shift跟踪算法

针对经典Mean-Shift算法要求相邻两帧间目标模板区域必须重叠的缺陷,结合Kalman滤波器,提出了改进算法。算法首先将Kalman滤波器预测的目标位置作为Mean-Shift算法中的初始搜索中心进行跟踪,然后再将Mean-Shift算法得到的新的目标位置作为下一帧Kalman滤波器的输入参数,循环执行。实验证明,该算法能够解决由于目标运动速度突然变化以及目标快速运动情况下所带来的相邻两帧间目标模板区域非重叠问题,而且对于一般的遮挡问题也能得到较好的效果。     

基于Mean-Shift的卡尔曼粒子滤波车辆跟踪算法研究

在视频车辆跟踪算法中针对传统粒子滤波的非线性、非高斯性可能导致跟踪过程的不准确性,提出一种基于Mean-Shift的卡尔曼(Kalman)粒子滤波算法。该算法利用建立基于目标颜色直方图特征模型对视频车辆目标进行建模,并将其与Kalman滤波相结合进行更新;通过采用Mean Shift算法将Kalman滤波器引用到粒子滤波器当中,通过预测迭代,从而达到对车辆的运行轨迹的修正。将先验信息预测与粒子滤波相结合在保持跟踪系统整体上的非线性、非高斯性,兼顾了卡尔曼滤波局部的线性高斯特性。实验结果表明,该方法与传统粒子滤波方法相比,具有较好的实时性和较高的准确率,能够准确稳定地对目标车辆进行跟踪。     

团块与Mean-Shift结合的局部遮挡目标跟踪

传统的基于Mean-Shift的目标跟踪方法利用目标的全局特征进行跟踪,在局部遮挡情况下跟踪效果不佳。提出一种基于团块建模和Mean-Shift相结合的利用目标局部特征的运动目标跟踪方法,对目标进行团块建模,利用Mean-shift算法对各团块进行跟踪,在此基础上确定目标新位置。该方法能够在目标发生局部遮挡时,自动选取未被遮挡的团块的跟踪结果来确定目标的位置。为了提高方法对背景干扰的鲁棒性,采用背景加权的Mean-Shift算法。实验结果表明：该方法在局部遮挡的情况下可较好地进行目标跟踪,跟踪效果优于报导的基于Mean-Shift的方法。     

基于改进射线矢量法的手部轮廓与手势实时跟踪方法

目前,在视频分析和处理过程中,运动物体的实时检测和与轮廓跟踪作为计算机视觉分析识别的基础,已变得越来越重要了.改进了传统的射线矢量法表示物体形状的方法,并结合拆分法和聚合法对单帧图像进行分割,以得到完整而准确的手部曲线,在相邻帧之间采用了Kalman滤波器估计帧间手部运动的轨迹来实现跟踪过程.该方法很好地克服了传统射线矢量法所无法表示的形状的缺陷,能够准确地跟踪手部的运动以及各种手势.     

基于运动估计的Kalman滤波视频对象跟踪

提出了一种利用Kalman滤波对运动目标的形心进行预测,从而实现视频对象跟踪的算法。首先进行视频对象分割,求出运动目标的形心。再利用视频序列中连续两帧的形心和运动矢量信息,用Kalman滤波对运动目标的形心在下一帧的位置进行预测,从而快速、有效地自动跟踪多个目标对象。实验结果表明,该算法对运动目标的出现和消失,以及非刚性物体的尺度变化和变形,具有较强的鲁棒性。     

海上运动目标跟踪系统的设计

为实现对海上运动目标的实时跟踪,克服跟踪效果易受到严重遮挡影响的缺点,建立了一套实时跟踪系统,并且结合目标的运动信息与新的模型更新策略,对均值漂移与卡尔曼滤波器相结合的跟踪算法做出了改进.当运动船只被遮挡的比例较大时,先用估计出的目标速度矢量更新卡尔曼滤波器,并用相应的模型更新策略更新目标模型以提高模型相似性度量的精确性,再单独利用滤波器进行跟踪,取得了较好的跟踪效果.实验结果表明,该系统可以较好地实现海上运动目标的跟踪,并且改进后的算法具有良好的实时性和鲁棒性.     

一种改进的移动机器人轨迹跟踪迭代学习方法

通过对轮式移动机器人轨迹跟踪优化问题的研究,提出了一种适应性强、收敛速度快且跟踪误差小的迭代滤波学习控制方法,充分发挥了迭代学习控制和Kalman滤波算法的优势,通过引入状态补偿项和设计新的迭代学习增益矩阵对迭代学习律进行了改进。改进的迭代学习控制能够更快速、更精确、更有效地跟踪期望的圆轨迹。采用离散的Kalman滤波器对干扰和噪声进行滤波,抑制了干扰和噪声对轨迹跟踪的影响,使该控制算法更适合于工程应用。计算机实验和仿真表明该方法具有较好的轨迹跟踪能力。     

窗宽自适应Mean-Shift跟踪算法

针对固定窗宽Mean-Shift算法在目标运动速度过快或尺度发生明显变化时可能导致跟踪失败的问题,提出一种窗宽自适应的Mean-Shift跟踪算法。该方法基于均值漂移矢量预测跟踪窗口中心位置,同时自动调整跟踪窗口大小,保证目标始终处于跟踪窗口内部,使算法得以准确定位目标;在确定空间位置后,利用基于Bhattacharyya系数的二分法自动选取窗口缩放比例,得到与目标尺度一致的跟踪窗口。实验结果证明,该方法能很好地定位目标的空间位置和尺度。     

一种基于Kalman滤波的视频对象跟踪方法

为了更加准确地预测对象的位置和运动，利用刚体运动模型导出最佳Kalman系数，通过Kalman反馈滤波器对Moscheni等人提出的视频对象分割与跟踪算法进行改进，提出了一种将离散Kalman滤波技术用于视频序列的对象跟踪方法。这种方法可用于有关场景描述的各种应用领域中，如在机器视觉的研究中，对动态场景进行分析与理解；在基于对象的视频编码中（如MPEG-4），对视频对象进行分割后，分别进行编码，从而改善编码的可分级性及编码效率。实验结果表明，采用这种方法可以有效地改善时间-空间分割和目标跟踪，有助于更好地理解动态场景，并表现出良好的鲁棒性。     

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.     

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.     

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.     

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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