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"菲特"在浙江引发了全省性暴雨和大暴雨天气。本文主要是通过NECP资料从大尺度环流形势、动力、热力和水汽条件等方面分析台风暴雨特征和形成机理,结果表明:(1)从环流形势来看,暴雨可以分为两个阶段,第一阶段主要由台风环流造成,第二阶段由残余低压环流和冷空气共同作用而引发;(2)暴雨水汽来源为副高南侧的东风急流,"丹娜丝"的存在有利于较强水汽通量的维持;(3)低层辐合高层辐散的分布有利于"菲特"强度的维持,暴雨中心辐合辐散交替分布,近地面辐合的增强预示着暴雨增幅;(4)弱冷空气的侵入有利于低层能量锋区的加强,促进降水。 相似文献
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利用常规观测资料、自动气象站观测资料及NCEP1°×1°再分析资料,对2016年10月和2018年9月登陆我国华南沿海的2次台风在浙江省产生的暴雨过程进行对比分析,结果表明:(1)1622号台风“海马”暴雨属于台风本体环流降雨,1822号台风“山竹”暴雨属于台风远距离暴雨。(2)前者水汽主要来自南海,沿台风低压环流及副高边缘的偏南风急流向暴雨区输送,后者水汽主要来自东海和西太平洋,沿副高西南侧的东南气流向暴雨区输送,前者急流强度和水汽通量均强于后者。(3)前者过程后期才有干冷空气从底层侵入,强度较弱,暴雨中尺度系统特征不明显,降水对流性较弱,后者整个过程都有干冷空气侵入,前期来源于对流层低层,后期来源于对流层高层,冷空气的侵入激发了中尺度对流系统的发生发展,降水对流性较强。(4)2次过程的动力学特征也有所不同,前者正涡度中心发展高度比后者低,但强度偏强,后者辐合辐散发展高度比前者深厚,但强度偏弱。 相似文献
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《科技通报》2017,(9)
受1323号台风"菲特"登陆闽北和1324号台风"丹娜丝"沿127°E以东海域北上的共同影响,浙江省出现了大范围特大暴雨,降雨强度为历史台风第一位;降雨分布异常,最强降雨出现在浙江北部地区,而非台风登陆点附近的东南沿海地区。特别是"菲特"减弱消亡后,浙北地区特大暴雨依然持续。利用NCEP1°×1°再分析资料和多普勒雷达等非常规资料对其成因展开分析,发现"菲特"与"丹娜丝"构建的双台风偏东急流使浙江出现了水汽输送、低空辐合和强迫抬升等机制的加强和持续,引发中小尺度对流强烈发展,是本次双台风特大暴雨的主要影响机制。其中偏东急流在浙北地区长时间持续,并与弱冷空气结合,导致浙北14个县(市、区)过程雨量破当地台风最大过程雨量记录。 相似文献
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通过分析0505号台风“海棠”暴雨过程中的湿位涡及其各分量的变化,表明负值MPV1密集区与强降水中心相对应,MPV1的变化比降水量的变化有一定的提前量,且MPV1随高度向台风移动方向倾斜,这对预报台风移动路径和暴雨落区有一定的指导意义。 相似文献
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Marjorie Armstrong-Stassen Margaret Landstrom Ramona Lumpkin 《The Information Society》1998,14(2):153-164
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
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A joint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology his co-workers from Norway US 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 the National Academy of Sciences on September .…… 《中国科学院院刊(英文版)》2008,22(1):6-7
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
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Caroline Haythornthwaite 《The Information Society》2001,17(3):211-226
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
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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
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Puay Tang 《The Information Society》1998,14(1):19-31
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
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Milton Mueller 《The Information Society》2001,17(3):151-163
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
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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.…… 《中国科学院院刊(英文版)》2008,22(1):15-15
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
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《中国科学院院刊(英文版)》2014,(3)
<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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Chinese Scientists Use Earth Observation Technologies to Study and Protect Wild Camels 总被引:1,自引:0,他引:1
《中国科学院院刊(英文版)》2014,(3):267-268
<正>Chinese scientists plan to apply Earth Observation technologies to protect the critically endangered wild camels(Camelus ferus).With the help of remote sensing,satellite positioning,geographical information system and wireless sensors networks,they will be able to access the distribution and population of the wild camels and protect their habitats.The project will be carried out by the International Research Center for Wild Camel Conservation,which was jointly established earlier this year by the Institute of Remote Sensing and Digital Earth(RADI)of the Chinese 相似文献
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WANG Sijia 《中国科学院院刊(英文版)》2014,(2):192-194
<正>The Paul Gerson Unna Research Group on Dermatogenomics was founded in October 2012 at the Partner Institute for Computational Biology.The ultimate goal of the group is to understand the biology of skin and skin appendages. 相似文献