基于全方位视觉的运动目标检测与定位方法

针对全方位视觉的运动目标检测,存在背景非常复杂,光照变化等噪声干扰明显等难点;在进行运动目标定位时,也需要消除当目标发生一定分裂时对定位结果的影响.为了滤出噪声,对目标准确定位,提出一种采用改进的背景消减法和区域成长法的运动目标检测与定位方法.本文首先采用背景消减法分割运动目标,在背景消减时利用最大方差比阈值法来滤除噪声,然后利用改进的区域成长法定位出目标.实验结果表明方法简单有效,能准确检测与定位出全方位视觉复杂背景下的运动目标.     

基于图像匹配的运动背景补偿方法

本文提出了在运动背景下车辆检测的一种有效的算法。首先对前后两帧进行稀疏块匹配，计算出摄像机全局运动速度和方向，经过运动补偿后再通过两帧差分检测出运动区域，最后利用形态学膨胀消除边缘断裂，后经过种子填充。计算连通域面积，去除噪声区域。实验表明，在运动背景的车辆检测应用上，能够较准确地提取出目标车辆。     

基于双阈值运动区域分割的AdaBoost行人检测算法

结合单目摄像机静止拍摄的视频序列使用背景差法或AdaBoost算法检测行人时分别存在易受噪声干扰或检测速度慢的问题,提出一种双阈值运动区域分割的AdaBoost快速行人检测算法。首先建立背景帧,利用前景帧与背景帧的差分图像拟合噪声曲线,提取噪声与亮暗运动目标的阈值,消除噪声,分割出运动区域;然后通过AdaBoost学习算法选择少量有效的Haar-like弱矩形特征构造强分类器;最后在运动区域利用强分类器检测是否包含行人。实验结果表明,该方法迅速缩小了检测范围,加快了检测速度,降低了误检率。     

一种改进的适用复杂场景的运动目标检测算法

针对传统运动目标检测算法中存在的“拖影”、光变干扰、阴影等问题,提出了一种改进的更具鲁棒性的检测算法.基于背景边缘检测差并通过两次结合帧间差分法以及颜色偏差用以消除噪声和减低运动目标边缘断裂现象,从而获取运动目标的完整轮廓,同时采用双向模板填充算法进行运动目标的分割,最后通过数学形态学滤波和连通域分析来进一步去除噪声和填补空洞,获得完整理想的运动目标区域.实验结果证明,相对于传统的帧差与背景差分检测算法,能够有效地克服阴影和光扰所产生的噪声问题,可以在复杂背景下准确地检测分割出运动目标,并满足实时性要求.     

一种快速的视频序列运动分割方法

提出一种视频序列运动分割的实时方法,该方法通过两次背景更新提取运动前景,其中长程背景更新检测噪声运动区域,并将长时间停留在场景中的物体纳入背景范围,短程背景更新利用单高斯分布模型实现对光线缓慢变化的适应。采用基于颜色空间的方法实现对阴影的消除,通过投影分割提取出不同的运动目标。试验证明该方法能够快速、精确地实现视频序列中多个运动目标的分割,消除背景噪声运动、目标阴影以及场景变化的影响。     

一种基于奇异点检测的光流场去噪方法

针对各种滤波方法对光流场进行去噪处理时会造成目标运动矢量改变的不足,提出一种基于奇异点检测的光流场去噪方法,利用表征信号奇异点特征的Lip指数建立噪声矢量判定准则,可以在目标无损的情况下检测出光流场噪声并消除。实验证明该方法能较好地消除噪声,同时不会造成目标运动矢量的损失。     

基于几何形状特征的运动目标判决方法

为了室内安全监控异常报警任务的需要,文章在对运动检测后的二值图像进行形态学后处理,消除细小噪声、平滑物体边界,对处理后仍保留的大面积伪运动目标区域,通过提取和分析面积、纵横比等几何形状特征参数,提出了一种运动目标判决方法.该方法有利于消除虚假报警,对基于安全报警系统的异常检测具有一定的意义.     

一种改进的基于混合高斯模型的运动目标检测算法

运动目标检测是实现目标跟踪和行为分析等任务的基础。在运动目标检测中,消除背景与噪声的干扰,从而将运动目标从图像中分离出来一直是研究的重点。混合高斯模型法被广泛地应用于运动目标检测,对存在小幅度运动的背景有较好的抗干扰能力,并且能提取出较完整的运动目标,但是同时存在噪声干扰,且对阴影抑制效果较差。针对传统混合高斯模型法的不足,提出一种改进的基于混合高斯模型的运动目标检测算法,利用帧差法对光照突变适应性较好和算法简单的特点,将传统混合高斯模型法与和四帧差法结合。实验结果表明,该方法能够有效地消除复杂环境中的噪声,并对阴影有一定的抑制作用,提高了运动目标检测的准确性和完整性。     

体育视频中的运动员检测与跟踪

利用自适应高斯混合模型对视频图像进行建模,从图像序列中获取背景图像并提取运动区域,利用像素的颜色信息从背景图像中提取绿色球场。为提高运动员检测的准确度,利用纹理相似性度量方法消除运动区域中的阴影,用形态学方法消除区域内的裂缝,根据球场信息去除球场外的噪声。改进了CamShift算法,并应用该算法对运动员进行跟踪。     

基于相关系数的运动目标检测算法

运动目标检测是实现目标跟踪、交通监控、行为分析等任务的基础。通过计算相邻两帧之间对应行和列的相关系数,利用运动目标区域相关系数相对较小的特点,分割出运动目标区域,进而利用逐点匹配算法准确地检测出运动目标。该算法可以使用于复杂背景下多运动目标的检测,算法具有运算量小,对噪声不敏感等特点。实验表明,该算法可以准确分离检测出所有运动目标,稳定性好,运行速度快,适合于对运动目标的实时检测。     

Notes on terrorism and data processing

Terrorism relies on mindless violence to achieve its objectives. Historically it has been employed as a conscious strategy to retain or achieve power by both purportedly legitimate governmental bodies and their opponents. Modern terrorists have begun to refocus their efforts on disruption of the social fabric. Terrorists have failed to recognize the role of DP in perpetuating the social/economic structure, but there have been isolated acts of terrorist violence directed at computer facilities since February 1969. There are many vulnerabilities in DP that terrorists could exploit for their own ends.     

Thermodynamic modeling of Cr–Nb and Zr–Cr with extension to the ternary Zr–Nb–Cr system

The total energies of Laves phases in the Cr–Nb and Zr–Cr systems have been calculated by the pseudo-potential VASP code with a full relaxation of all structural parameters. The special quasirandom structures (SQSs) have been constructed and their total energies have been calculated by the VASP code to predict the enthalpies of mixing for bcc and hcp solid solution phases. The phonon calculations for the C14 and C15 Laves phases have been performed to analyze the phase stability at elevated temperatures. The experimental study on the Zr–Cr system has been carried out at different temperatures to determine the phase boundaries. Based on these results, thermodynamic models of Cr–Nb and Zr–Cr with extension to the ternary Zr–Nb–Cr systems have been developed in this work by using the CALPHAD approach.     

Introducing the personal software process

The personal software process (PSP) has been developed by the Software Engineering Institute (SEI) to address the improvement needs of individual software engineers. It should also be of help to small projects and modest-sized software organizations. In a one-semester graduate-level course, engineers are introduced to measurement, planning, and quality control methods. A defined sequence of programming exercises are used to illustrate these methods and the exercise data are used to provide the students with feedback on their performance. The PSP course has been taught at five universities at both the graduate and senior undergraduate level. Various PSP introduction methods have also been tried at four industrial organizations, but the course format has also been found most effective. Results to date indicate that PSP training motivates engineers to use disciplined methods and it helps them to achieve significant quality and productivity improvements. While PSP principles have been demonstrated with software engineering students, their effectiveness has not yet been measured in industrial practice. This paper describes the PSP process, the strategic approach and experience to date.This work is supported by the US Department of Defense.     

A New Efficiency-Weighted Strategy for Continuous Human/Robot Cooperation in Navigation

Autonomous robots are capable of navigating on their own. Shared control approaches, however, allow humans to make some navigation decisions. This is typically executed either by overriding the human or the robot control at some specific situations. In this paper, we propose a method to allow cooperation between humans and robots at each point of any given trajectory so that both have some weight in the emergent behavior of the mobile robot. This is achieved by evaluating their efficiencies at each time instant and combining their commands into a single order. In order to achieve a seamless combination, this procedure is integrated into a bottom-up architecture via a reactive layer. We have tested the proposed method using a real robot and several volunteers, and results have been satisfactory both from a quantitative and qualitative point of view.     

Context-aware broadcasting approaches in mobile ad hoc networks

The aim of this paper is to compare different context-aware broadcasting approaches in mobile ad hoc networks (MANETs) and to evaluate their respective performances. Message broadcasting is one of the core challenges brought up by distributed systems and has therefore largely been studied in the context of traditional network structures, such as the Internet. With the emergence of MANETs, new broadcasting algorithms especially geared at these networks have been introduced. The goal of these broadcasting algorithms is to ensure that a maximum number of nodes deliver the broadcasted message (reliability), while ensuring that the minimum number of nodes retransmit the broadcasted message (efficiency), in order to save their resources, such as bandwidth or battery. In recent years, as more and more mobile devices have become context-aware, several broadcasting algorithms have been introduced that take advantage of contextual information in order to improve their performance. We distinguish four approaches with respect to context: (1) context-oblivious approaches, (2) network traffic-aware approaches, (3) power-aware approaches, and (4) location-aware approaches. This paper precisely aims at presenting these four different broadcasting approaches and at measuring the performance of algorithms built upon them.     

Multiapplication smart card: Towards an open smart card?

Smart cards were invented four decades ago so as to keep data secrets and to process them secretly. Even though their main goal are still the same today, the smart cards have been subject to many evolutions at both their hardware and software levels. Indeed they have been the target of numerous attacks and new demands from the market. These demands have expanded their domains of application. When they were born and during some thirty years smart cards have been monolithic platforms with a fixed piece of software dedicated to one single application. But in the mid 90's, some technologies appeared that have broken this situation by enabling to easily host several applications on the same card. These new technologies have changed the business models and pushed the smart cards towards new domains and to a world where they will integrate lots of new functionalities.The aim of this paper is to give an overview of the evolution of the smart cards (and of their application domains) from monolithic static pieces of hardware and software to a flexible multiapplication platforms. This paper also explores the possibilities to see open multiapplication cards in the future and exposes the breakthroughs that are required to achieve in order to produce such cards.     

Power Consumption Modeling of Skid-Steer Tracked Mobile Robots on Rigid Terrain

Power consumption is a key element in outdoor mobile robot autonomy. This issue is very relevant in skid-steer tracked vehicles on account of their large ground contact area. In this paper, the power losses due to dynamic friction have been modeled from two different perspectives: 1) the power drawn by the rigid terrain and 2) the power supplied by the motors. Comparison of both approaches has provided new insight on skid steering on hard flat terrains at walking speeds. Experimental power models, which also include traction resistance and other power losses, have been obtained for two different track widths over marble flooring and asphalt with Auriga- beta, which is a full-size mobile robot. To this end, various internal probes have been set at different points of the power stream. Furthermore, new energy implications for navigation of these kinds of vehicles have been deduced and tested.     

It’s time to put smart cards in loyal shoppers’ pockets

When it comes to managing customer relationships, the majority of companies are making serious mistakes, says Professor Merlin Stone of the Bristol Business School at the University of the West of England. Marketeers have been obsessed with obtaining a single, centralised, real-time updated view of their customers and they have been distracted by the Internet and mobile telephony. As result they have overlooked the smart card, which could be the very integrating tool that they need.     

Enhancing Organizational Resilience Through Emergency Planning: Learnings from Cross‐Sectoral Lessons

After every emergency exercise or actual incident, reports are circulated that usually identify lessons that have been learned from the event. This paper identifies recurring themes from the lessons learned that can be widely applied across sectors. Typically, lessons are expressed in a form that is specific to the actual event that has transpired, the sector in which it has occurred, and the aims of the reporting organization. Reports relating to seven incidents that have occurred in the United Kingdom and internationally, from a range of sectors and with varying parameters, have been reviewed. It is concluded that organizations can become wiser by looking at incidents outside their own sector and by using these recurring themes to explore the resilience of their emergency plans. Recommendations are also made for best practices to improve the learning of lessons within organizations.     

Mobile educational features in authoring tools for personalised tutoring

One important field where mobile technology can make significant contributions is Education. In the fast pace of modern life, students and instructors would appreciate using constructively some spare time that they may have, in order to work on lessons at any place, even when away from offices, classrooms and labs where computers are usually located. In this paper, we describe a mobile authoring tool that we have developed and is called Mobile Author. Mobile Author can be used by human instructors either from a computer or a mobile phone to create their own Intelligent Tutoring Systems (ITSs) and to distribute them to their students. After the ITSs have been created, students can also use any computer or mobile phone to have access to theory and tests. The tutoring systems can assess the students' performance, inform the data-bases that record the students' progress and provide advice adapted to the needs of individual students. Finally, instructors can monitor their students' progress and communicate with their students during the course. The mobile features of both the authoring tool itself and the resulting ITSs from it have been evaluated by instructors and students, respectively. The results of the evaluation showed that mobile features are indeed considered useful.