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1.
吴胜  苏琴 《情报探索》2011,(11):104-106
指出已有的研究没有将网站定位分析结果和网站开发联系起来。考虑到网站的特点,结合面向资源的思想,提出了面向资源的网站定位模型。利用该模型进行网站定位分析时,要依次考虑网站的类型、用户和内容。利用该模型进行网站定位分析时,分析结果可以直接作为网站开发的基础。  相似文献   

2.
石敏力 《科技通报》2012,28(4):174-175,184
首先介绍灰度模型的目标定位算法,在该算法基础上提出了一种改进的算法,将主动形状模型的灰度图像中目标定位算法应用到视频图像中,同时针对处理结果进行科学评价。实验结果证明了本文提出算法的可行性和高效性。  相似文献   

3.
目的:研究三维模型交互式定位确定断层图像感兴趣结构像素坐标值的方法。方法:提出一种结合VTK(Visualization Toolkit)可视化工具包的提取类库功能与针刺取点算法特点的方法,通过交互式操作获取三维模型世界坐标,实现断层图像结构定位。结果:以中国可视化人体数据集肠道数据为基础,构建了一段肠道三维模型。通过交互式定位技术得到断层图像感兴趣结构的像素坐标。结论:实验结果表明,该定位技术实现方法可行,具有良好的交互性和精确度。  相似文献   

4.
本文主要讨论了杆的影子坐标与日期时间和经纬度的关系,将太阳和地球的系统作为天球系统处理,利用了穷举法、粒子群优化算法、参数拟合等算法,建立了影子长短模型、经纬度判断模型解决了如何利用影子进行定位的问题。  相似文献   

5.
为有效对运动图像的目标特征进行较好定位与跟踪,提出了一种基于多权值相似均衡的运动图像循环定位跟踪算法。该算法首先利用颜色与纹理构建运动图像的空间特征分布跟踪模型,通过特征聚类对运动图像自动划分目标空间,然后根据目标模型的相似函数计算多个特征权值对目标模型进行选择性均衡,并结合特征权值自适应迭代定位跟踪信息,以最大程度地对运动图像的细节特征进行定位跟踪。实验结果表明,该算法优于传统的定位跟踪方法,尤其在跟踪目标受到外界干扰时能够得到比较理想的跟踪效果。  相似文献   

6.
本文以城市供水管网的爆管定位为核心研究内容,通过对该问题的初步研究过程中,为城市供水管网系统建设及事故的安全处理解决提供合理的解决方案,并建立了爆管检测定位的神经网络模型,以期达到故障点的快速定位。  相似文献   

7.
定位技术是无线传感器网络的重要技术之一,其中基于RSSI测距的定位技术以便捷、精确度高成为首选技术。文章为了实现对商场走失儿童的快速定位设计了一个基于RSSI和三边定位技术的实时定位系统。该系统利用4G网络进行定位请求,RSSI测距技术对未知节点进行测距,最后基于三边定位技术编写算法。该算法经过仿真实验精度完全符合要求。  相似文献   

8.
孙涛 《科技广场》2010,(3):51-53
本文利用误差改正模型方法,得到精密单点定位总模型,利用这个模型对多个历元数据进行解算,并与非改正结果进行了比较、分析。分析结果表明,模型能够显著提高单点定位的精度。  相似文献   

9.
孙涛 《科技广场》2011,(3):46-48
本文利用误差改正模型方法,得到精密单点定位总模型,利用这个模型对多个历元数据进行解算,并与非改正结果进行了比较、分析。分析结果表明模型能够显著提高单点定位的精度。  相似文献   

10.
恐怖人员在网络中发送恐怖信息时,根据恐怖信息来源的网络节点能够实现对恐怖人员的准确定位。恐怖人员发送恐怖信息与正常信息的属性不同,伪装性较强。利用传统的恐怖信息挖掘方法进行恐怖人员定位时,固有的恐怖信息被伪装,难以进行恐怖信息的准确挖掘,造成恐怖人员定位准确性降低。为此,提出一种基于聚类算法的网络中恐怖信息挖掘方法。在网络信息中筛选有价值的恐怖信息特征,从而为恐怖信息挖掘提供依据。利用聚类算法,对所有恐怖信息特征进行聚类处理,能够实现对网络中恐怖信息的挖掘,最终实现了对恐怖人员的定位。实验结果表明,利用该方法进行网络中恐怖信息挖掘,能够实现对恐怖人员的准确定位。  相似文献   

11.
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   

12.
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   

13.
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   

14.
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   

15.
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.  相似文献   

16.
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   

17.
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   

18.
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   

19.
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.  相似文献   

20.
<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  相似文献   

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