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1.
本文通过分析红外图像中的小目标和背景特征,提出了基于Contourlet变换和支持向量回归(SVR)自适应滤波器的检测方法。该方法首先采用Contourlet变换抑制背景杂波;然后用基于SVR的自适应滤波器对高频系数进行滤波处理,可以大大提高图像的信噪比;最后根据目标运动的连续性和轨迹的一致性检测小目标,并利用流水线结构的序列处理方法进一步提高检测性能。最终实验结果表明:该方法可显著提高红外小目标的检测概率,实现远距离弱小目标的检测。  相似文献   

2.
本文主要分析了智能视颇分析技术.研究了视频监视系统中的运动目标检测与跟踪方法,提出了基于背景统计模型估计的方法在基于运动目标检测与跟踪算法的智能视频监控系统中的实际应用方案,并设计了基于智能视频分析技术的数字化监狱网络监管系统的实现方案,包括基于DSP处理和单片机控制的运动目标检测与跟踪系统的硬件组成方案,和基于运动目标检测与跟踪算法的智能视频监控系统控制图像处理电路以及算法流程.  相似文献   

3.
利用雷达图像的特点,通过边缘检测,轮廓跟踪,图像融合等一系列的方法,得到雷达图像和背景图像的融合。实验结果表明,文章所运用的方法在雷达图像处理中是非常有效的。  相似文献   

4.
目标跟踪问题的应用背景是雷达数据处理,即雷达在搜索到目标并记录目标的位置数据,对测量到的目标位置数据(称为点迹)进行处理,自动形成航迹,并对目标下一时刻位置预测。本文讨论在蒙特卡罗方法下采用Kalman滤波方法对单个目标航迹进行预测,借助于Matlab仿真工具评估实验效果。  相似文献   

5.
本文提出一种低空补盲雷达剩余杂波点迹过滤方法,该技术采用实时处理方式,对每一个新报入的点迹立即按照检测规则采用帧间处理技术进行识别处理。可把低空补盲雷达上报的点迹识别为固定地物杂波类点迹、运动目标类点迹、孤立噪声类点迹和待确认可疑类点迹共四类,大大减轻后续的点迹处理负担并提升目标的跟踪效果。  相似文献   

6.
在强干扰环境下对多载波雷达信号的幅度检测是实现空中目标打击的关键技术。传统方法中,对雷达信号的幅度检测采用时频耦合算法,如果信号和背景噪声有很强干扰和多载波特征时,检测性能不好。提出一种基于分数阶Fourier时频耦合的信号幅度检测算法。构建强干扰环境,描述雷达信号的宽度和深度等特征量,对多载波雷达信号进行分数阶Fourier变换,对目标回波的尺度和时延进行估计,求解相位模糊数搜索结合解,得到雷达信号参数相位补偿结果,根据雷达信号特征量聚点塑造特征量模型运算雷达信号的特征量聚点,获取高特征量聚集区域,通过后置的高阶累积量切片,使信号的累积量增大,而噪声被抑制提高了检测精度。仿真实验表明,算法的检测概率较高,幅度检测能很好地跟踪信号幅度的变化。  相似文献   

7.
微弱目标的检测与跟踪是通过利用诸如雷达传感器、光学传感器、视觉传感器等提供初始观测信息,发现对象并估计对象的状态(例如,姿态,速度,航迹等)参数。文章对微弱目标的检测与跟踪技术领域的专利申请进行了数据分析,对该领域专利申请量、技术原创国与目标国、申请人分布等进行了统计分析。  相似文献   

8.
视频运动目标检测和跟踪技术是智能视频监控的关键技术。基于这两方面展开研究,提出了自适应场境的运动目标跟踪方法。系统由背景差分实现目标检测,由目标区域LK光流预测实现目标跟踪,并融合了"运动"背景局部更新来实现跟踪系统对环境的自适应性。最后用VC++和OpenCV软件平台设计了监控系统的演示环境,在简单场景中实现了运动目标的检测和跟踪,初步验证了系统算法的可行性和可实现性。  相似文献   

9.
《科技风》2015,(20)
现有交通监控系统中所应用的各种技术只能对交通的流量特征进行监控,无法对交通状况做出及时有效的判断,细分交通的不同状态。本文在运动目标检测和跟踪的基础上,提出一种基于智能视觉识别,全新的信息获取和处理技术与交通多状态识别系统。该交通监控系统利用监控图像帧差灰度变化区间,进一步研究目标的行为状态和方式。对更新图像背景,图像处理和计算机视觉具有较高的检测精度。  相似文献   

10.
由于传统Camshift算法在运动目标被遮挡、受到背景同色干扰、运动过快时存在跟踪失败问题,因而文中提出一种融合目标检测与混合特征描述的跟踪算法。针对传统单一的颜色直方图的描述,提出基于感知哈希算法、纹理特征与颜色特征相融合的混合特征表达方式表征运动目标区域。针对目标运动过快或者被遮挡的干扰,引入Kalman滤波来预测目标出现的位置,并结合运动目标检测,加快目标搜索过程,提高Camshift算法在目标跟踪与搜索时的准确性与时效性。选取不同场景下的多组视频进行实验,结果表明,跟踪算法具有较好的鲁棒性,验证了算法的有效性。  相似文献   

11.
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China's science enterprise by making S&T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party's Leading-member Group at CAS, which was held from 7 to 11 January in Beijing.  相似文献   

12.
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors.  相似文献   

13.
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants."  相似文献   

14.
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007.  相似文献   

15.
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction.  相似文献   

16.
Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies.  相似文献   

17.
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means.  相似文献   

18.
Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP.  相似文献   

19.
Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.  相似文献   

20.
Prof. SUN Changpu from the CAS Institute of Theoretical Physics and coworkers from University of Basel in Switzerland have worked out a way --at least in theory --to split a beam of molecules according to their chirality. The technique involves passing the molecules through three different laser beams and is similar to the famous Stern-Gerlach effect, whereby a beam of atoms passing through a magnetic field is split in two according to the atoms' spin states (Phys. Rev. Lett. 99 130403).  相似文献   

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