引入视觉显著性的多特征融合跟踪

针对大多数目标跟踪算法采用单一特征描述目标,在背景区域出现相似的干扰特征时跟踪精确度较低的问题,提出了一种引入视觉显著性的多特征融合的目标跟踪算法。首先,采用视觉显著性机制处理颜色直方图得到显著性特征,再使用混合特征策略融合显著性特征和BRISK(binary robust invariant scalable keypoints)特征,获取目标前景和背景模型;其次,运用双向光流检测和误差度量提取动态特征,并使用自适应搜索机制提取候选目标区域的静态特征,融合动态特征和静态特征;最后,根据匹配算法估算目标跟踪框的自适应尺度及中心,确定目标在当前帧图像中所处的位置。实验结果表明,该算法能够处理强烈光照变化、目标尺度变化、快速运动及部分遮挡等情况下的目标跟踪问题,并实时稳定地获得单目标跟踪结果。     

基于SCM的虹膜干扰区域去除算法

为了提高虹膜识别率,提出了一种新的睫毛及眼睑区域定位算法。为了提取呈不同角度分布的睫毛,结合SCM模型和动态交叉熵准则对归一化虹膜图像进行多次迭代,根据图像的灰度分布特性,选取合适迭代结果,对多幅迭代图像进行边缘像素点跟踪融合来获得理想的干扰区域轮廓定位。采用高斯金字塔尺度变换与霍夫变换相结合的方法对眼睑的类椭圆区域进行拟合,进而获得连续的眼睑边缘,实现对归一化虹膜图像中干扰区域的准确定位。实验结果验证了方法的有效性。     

基于运动目标特征的关键帧提取算法

针对运动类视频特征不易提取且其关键帧结果中易产生较多漏检帧的问题,提出基于运动目标特征的关键帧提取算法。该算法在强调运动目标特征的同时弱化背景特征,从而防止由于运动目标过小而背景占据视频画面主要内容所导致的漏检和冗余现象。根据视频帧熵值将颜色变化明显的帧作为部分关键帧,对颜色未发生突变的帧根据运动物体的尺度不变特征变换（SIFT）获得帧内运动目标的特征点;最后分别根据帧熵值及运动物体SIFT点分布提取视频关键帧。实验表明该算法所得关键帧结果集不仅漏检率较低且能够准确地表达原视频内容。     

基于视觉感知的运动目标跟踪算法

针对运动目标跟踪问题, 为解决跟踪过程中因遮挡、目标尺度变化等易造成跟踪失败的现象, 提出一种基于视觉感知的跟踪算法。该算法以神经元响应为视觉特征, 首先从自然图像中学习初级视皮层细胞感受野; 然后计算背景图像和视频序列图像的神经元响应并得出差值, 与动态阈值比较, 识别出运动目标, 通过迭代实现目标跟踪。多类别实验结果表明, 该算法实现了运动目标稳定跟踪, 目标跟踪准确率达93. 5%且鲁棒性增强, 与典型算法Camshift和SIFT相比, 提高了跟踪算法的准确性和鲁棒性。     

基于小波的大脑图像边界跟踪算法研究

准确提取医学图像中目标的边界在图像处理分析和医疗应用领域具有重要意义。针对大脑图像中纹理复杂,难以区分非正常区域和正常区域边界的问题,本文提出了一种基于小波多尺度分析的边界跟踪方法。该方法首先对原始大脑图像进行小波变换,得到图像的多分辨率表示,然后利用一种改进的轮廓跟踪算法对最低分辨率的图像进行跟踪,最终获得了大脑中非正常区域的边界。实验结果表明该算法可以有效地去除噪声以及脑部正常纹理的干扰,提取出目标特别是非正常区域的边界特征,执行效率高,跟踪准确。     

多分辨率LK光流联合SURF的跟踪方法

针对交通监控中运动目标形变、雾霾天气、高速、光照不均、部分遮挡等复杂情况导致Lucas-Kanade（LK）算法跟踪不稳定问题,提出基于多分辨率LK光流算法联合快速鲁棒性特征（SURF）的跟踪算法。所提算法构建图像多分辨率小波金字塔,解决传统LK算法中同一像素点帧间大尺度运动易丢失问题;同时联合SURF尺度不变特征变换算法,提取特征点进行光流跟踪,并制定自适应模板实时更新策略;在减少光流计算量的同时增强运动目标抗复杂环境的能力。实验结果表明,新方法中特征点匹配准确快速,自适应性强,在交通复杂化境中跟踪稳定。     

改进的抗遮挡MeanShift目标跟踪算法

传统MeanShift目标跟踪算法通过bin-bin颜色直方图表示目标特征,直方图中往往会混入背景颜色信息,造成跟踪不准确;同时由于MeanShift算法具有局部最优性,当目标受到严重遮挡丢失后,不能对目标重新定位跟踪。为了解决上述问题,在颜色直方图和抗遮挡能力方面进行了改进。利用交叉bin颜色直方图代替传统的bin-bin颜色直方图表示目标特征,减少背景颜色的干扰,提高MeanShift算法跟踪精度;当目标受到严重遮挡丢失后,通过一种尺度变化调整机制,在全局范围内搜索目标位置,提高MeanShift算法抗遮挡能力。实验显示,改进后的算法不仅在背景干扰大时对目标的跟踪精度更高,而且当目标受到严重遮挡丢失后,也能够对目标重新定位跟踪。     

基于颜色布局描述子的改进ViBe算法

针对ViBe算法在检测运动目标时会有“鬼影”产生和在动态背景下会对目标检测过程中产生干扰造成运动目标误检的问题,结合颜色布局描述子（CLD）提取关键帧进行三帧差分、形态学后处理的技术,提出一种改进的ViBe算法。首先,通过CLD提取视频关键帧图像;然后,将所选取关键帧图像进行三帧差分,通过差分结果将含有运动目标的背景模型进行填充,得到真实的背景图像,再对运动目标进行检测,以达到消除鬼影的目的;最后,在背景模型更新的阶段加入自适应阈值的形态学处理技术,消除动态背景模型中的干扰信息。实验结果表明,所提算法在运动目标检测时在避免鬼影、抗动态背景干扰等方面表现出优越性,在相似度量阈值选取为0.67到0.72时,所提算法的准确率最高可以达到99.4%,可以理想地检测出运动目标的位置信息。     

利用Jetson TK1平台的行人运动目标跟踪系统

针对图像检测识别和目标跟踪技术中存在的抗遮挡性弱、无法应对目标丢失、对目标多尺度变化适应不了等问题,设计开发了基于Jetson TK1平台及计算机视觉OpenCV(Open Source Computer Vision Library)的行人运动目标跟踪系统,利用GPU高效图像处理能力,结合改进的KCF(Kernelized Correlation Filters)跟踪算法,实现对监控区域内行人的运动跟踪。实验结果表明,Jetson TK1平台的行人运动目标跟踪系统稳定可靠,具有良好的抗遮挡性和准确性。     

改进曲波变换的在图像角点检测中的应用研究

角点是图像目标的重要局部特征,角点检测在目标跟踪、运动估计、相机定标等方面都有重要的应用.曲波变换基于多尺度几何分析的思想,以边缘为基本元素能够同时获得对图像平滑区域和边缘部分的稀疏表达,是一种更适合图像处理特点的多尺度变换.为降低曲波的数据冗余性,采用有限脊波变换对曲波进行改进,并在此基础上提出利用Mallat模极大值原理进行角点检测的算法,实验结果表明该方法即使在有噪声的情况下仍然具有较高的稳定性和鲁棒性.     

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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