不规则单帧运动图像中三维姿态矫正技术研究

不规则单帧运动图像在目标成像与识别过程中会产生畸变和边缘动态失真,成像效果不好。提出一种基于RGB位平面分解的不规则单帧图像三维矫正技术,设计RGB位平面分解模型并对图像像素遍历机制进行改进,对单帧运动图像进行全局运动参数估计。把不规则的单帧运动图像纹理结构信息反映到灰度场空间中,得到图像全局运动空间单元三维姿态嵌入隐秘信息传导函数,实现对三维姿态矫正。实验结果表明,改进算法得到的姿态矫正偏移量比传统方法缩小,矫正精度较高,峰值信噪比提高,展示算法的优越性能,在运动图像融合和识别等领域具有很好的应用价值。     

视频帧色差突变图像的背景检测参量提取

对视频帧中运动目标提取是计算机视觉研究的重点课题,对视频帧色差突变图像的背景检测常受到背景色差干扰,目标检测性能不好。提出一种基于视频序列的双背景建模的视频帧色差突变图像的背景检测和参量提取算法,背景建模加入了光照突变处理机制,进行色差补偿。计算视频帧差背景内的突变信息感知概率和统计概率,对视频图像进行滑动平均建模,采用模极大值法进行边缘检测,得到基于灰度方差的视频帧色差稳定性检测的判别函数。将当前帧与背景帧相减,建立滑动平均背景模型,提取其背景差异性特征参量。仿真结果表明,该算法的检测性能较好,当背景发生变化时,如光照突变、人群数目突然增大时,具有较好的背景检测性能,处理光照突变方面的图像平滑性较好。     

跳水运动视频中的运动目标分割

针对跳水运动视频中的人体运动目标分割问题,提出一种简单有效的基于颜色特征运动目标检测及分割算法。首帧进行图像预处理,利用色相和亮度两个分量加强颜色差异,然后使用OTSU算法对图像进行阈值分割。结合RGB颜色空间启发式肤色聚类结果确定运动目标所在的连通区域,最终完成首帧运动目标的自动检测。有效地克服了复杂背景变化的影响,能够快速实现跳水运动目标的分割,且对运动对象的快速整体运动有较强的鲁棒性。     

运动目标在复杂背景中的检测

运动目标轮廓的有效提取,对于目标识别和跟踪是非常重要的,但是大量的背景景物增加了目标检测的难度。文中针对复杂背景下红外序列图像的特点,提出了一种实用的运动目标检测算法。首先,通过canny边缘检测算法,对输入图像进行边缘检测,然后把相邻两帧边缘图像进行场景对准,计算出相应的场景平移参数,根据这些参数,平移帧图像后做差分处理。在残差图像中,根据局部熵的图像分割法,对图像进行二值化处理,最终获得了比较完整的运动目标。实验表明,这种方法是有效的,且性能良好。     

运动目标在复杂背景中的检测

运动目标轮廓的有效提取，对于目标识别和跟踪是非常重要的，但是大量的背景景物增加了目标检测的难度。文中针对复杂背景下红外序列图像的特点，提出了一种实用的运动目标检测算法。首先，通过canny边缘检测算法，对输入图像进行边缘检测，然后把相邻两帧边缘图像进行场景对准，计算出相应的场景平移参数，根据这些参数，平移帧图像后做差分处理。在残差图像中，根据局部熵的图像分割法，对图像进行二值化处理，最终获得了比较完整的运动目标。实验表明，这种方法是有效的，且性能良好。     

基于改进的OTSU算法的视频处理

针对跳水运动视频中的人体运动目标分割问题,提出利用颜色信息进行运动目标检测和分割的算法。首先采用色相和亮度两个彩色分量加强图像中的颜色差异,使用OTSU算法对图像进行阈值分割,同时结合RGB颜色空间启发式肤色聚类,确定运动目标所在的连通区域,从而完成首帧运动目标的自动检测。在后续帧的处理中,以数学形态学方法进行自适应运动区域预测,运用改进的OTSU算法,提高了分割速度。实验表明,本方法有效地克服了复杂背景变化的影响,能够快速实现跳水运动目标的分割,且对运动对象的快速运动有较强的鲁棒性。     

基于运动帧补偿的多媒体块匹配稳像仿真实现

在对高速运动目标的多媒体视频采集中,因为风力、高速抖动等原因导致视频和图像采集模糊,稳定性差,需要进行对视频和图像等多媒体素材进行电子稳像处理,提高对图像目标的识别和检测能力。传统方法中采用块匹配方法构建电子稳像算法,因为运动帧补偿效果不好,稳像效果较差。提出一种基于运动帧补偿的多媒体块匹配电子稳像算法,进行GSM随机场建模和进行像素点关联传递迭代优化,将图像的前一帧作为参考帧对当前帧进行参数补偿,求得的全部帧图像对应的运动参数,实现对电子稳像算法改进。仿真实验表明,算法能保留图像中的特征的同时去除图像中含有的抖动,稳像处理性能较传统方法优越。改进方法在电子侦察、远程目标识别等领域具有优越的应用前景。     

基于边缘提取的会议视频图像快速解码算法研究

针对传统视频图像解码算法进行解码运算时,存在解码后视频图像失真率高、解码效率低的问题,提出基于边缘提取的会议视频图像快速解码算法.该算法采用边缘提取方法预处理会议视频图像,以获得会议视频图像的边缘掩膜,根据边缘掩膜对会议视频图像进行平滑处理.通过自适应抽帧方法增大视频图像中的序列场景,抽取未发生跳变的图像帧数.采用双向运动补偿插帧方法填充运动矢量,完成会议视频图像的快速解码.实验结果表明,所提出的基于边缘提取的会议视频图像快速解码算法,边缘提取误差低、解码失真率低、解码效率高,具有较高的实际应用价值.     

加速鲁棒特征匹配模糊动态场景混淆去除算法

动态场景曝光图像较为模糊,混淆复杂,对动态场景混淆去除是实现基于动态场景图像识别的运动目标检测的关键。针对传统方法中模糊混淆点配准不精,去混性能不好的问题,提出一种采用加速鲁棒特征匹配的模糊动态场景混淆去除算法,设计图像序列块曝光生成模型和边缘检测算法,抑制运动场景混淆图像边缘凹点灰度特征和混淆干扰,设计并行处理的分块检测方案提高处理速度,采用加速鲁棒特征匹配方法实现混淆去除。实验结果表明,采用该算法进行模糊动态场景图像的混淆去除处理,特征匹配精度高,去除混淆效果较好,在色彩自然效果保持和实时性方面优越传统方法,在基于图像处理的快速运动目标识别和动态场景恢复等领域具有很好的应用前景。     

随机体育运动图像捕捉点虚拟重建中凌乱误差控制

运动员进行不同的运动项目时,关节所成的角度,运动速度有差异,造成特征捕捉点不能很好对应关键区域,形成特征凌乱对应误差,影响形状基计算的准确性。传统的体育运动图像三维重建算法,受到形状基凌乱的影响,后期建模准确性很难控制。因此提出随机体育运动图像捕捉点虚拟重建中凌乱误差控制算法。利用因式分解法,建立人体运动时的三维动态仿真模型,运用stolt变换将所有图像捕获点的的方位偏移率调整为相同,使其在进行特征匹配时不会产生过大误差,对于过大的凌乱残余误差,进行三阶运动补偿,实现人体运动图像序列中的三维动态仿真建模。实验结果表明,这种算法提高了人体运动图像序列三维动态仿真的真实性。     

Students' Reactions to the Introduction of Videoconferencing for Classroom Instruction

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.     

Cooler temperatures inductive to locust outbreaks

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.     

Exploring Multiplexity: Social Network Structures in a Computer-Supported Distance Learning Class

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.     

Low doses of a red wine ingredient figh diabetes in mice

Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said.     

The Role of Intermediating Institutions in the Diffusion of Electronic Data Interchange (EDI): How Industry Associations Intervened in Denmark, Finland, and Hong Kong

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.     

How Electronic Publishers are Protecting Against Piracy: Doubts About Technical Systems of Protection

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.     

Rough Justice: A Statistical Assessment of ICANN's Uniform Dispute Resolution Policy

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.     

Prevalence of soft neurological signs in Chinese people

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.     

Molecular motor assembly of a biomimetic system

Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction.     

Monoculture Rubber Plantations Have Negative Ef ects on Controlling Splash Erosion

<正>In Xishuangbanna,one of China’s most biodiverse regions,landscape has changed dramatically during the past three decades due to the conversion of tropical rainforest to rubber plantations.In steep areas,terraces are often constructed before planting rubber trees,which causes two important changes in the soil:the destabilization of soil in the bench terraces and the increased vulnerability of unvegetated riser faces to erosion.Few studies have documented the nature and intensity of erosion on bench terraces.Prof.LIU Wenjie and his colleagues from the Xishuangbanna Tropical Botanical Garden(XTBG)conducted a study in Menglun County(21°5′39″N,101°15′55″E),Xishuangbanna to evaluate the influence