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31.
本文介绍了目前流行于网络的信息推送技术RSS及RSS阅读器,同时以EI Village 2检索系统为例,介绍了RSS的订制及阅读方法.  相似文献   
32.
Ei Village 2和Web of Knowledge 数据库平台的比较分析   总被引:5,自引:0,他引:5  
以INSPEC数据库为例,比较和分析了Ei Village 2和Web of Knowledge在检索功能、检索结果的处理、整合功能、个性化服务、检索效率及管理功能等方面的异同,并对网络环境下数据库检索平台的评价与选择提出了建议。  相似文献   
33.
构建基于J2EE规范的数字图书馆模型的探讨   总被引:2,自引:0,他引:2  
从软件工程的角度分析,数字图书馆实质是一个分布式管理信息系统。构建数字图书馆,就是构建一个分布式管理信息系统。J2EE的多层次的分布式应用模型和一系列开发技术规范,为构建数字图书馆平台提供了可靠保证。图1。参考文献11。  相似文献   
34.
基于P2P的适应性信息检索系统的设计   总被引:3,自引:1,他引:3  
针对现有搜索引擎的不足,提出了一个基于P2P的适应性信息检索系统设计方案,详细介绍了系统的各主要模块的功能和技术方法,进而分析了该模型的优势。  相似文献   
35.
36.
基于词向量扩展的学术资源语义检索技术   总被引:1,自引:0,他引:1  
[目的/意义] 尝试以统计的方法为指导思想,探究基于词向量扩展的语义检索技术来提升学术资源的语义检索能力。[方法/过程] 利用自然语言处理、文本挖掘技术,对采集来的学术资源(主要是学术论文)元数据进行预处理,结合word2vec词向量生成工具和elasticsearch全文检索引擎搭建语义检索系统,对学术资源进行语义检索的探索研究。[结果/结论] 本文提出的方法能够有效提升学术信息的检索效果,一定程度上实现学术资源的语义检索,并为后续语义检索的进一步研究提供借鉴。  相似文献   
37.
We have studied the efficiency of research in the EU by a percentile-based citation approach that analyzes the distribution of country papers among the world papers. Going up in the citation scale, the frequency of papers from efficient countries increases while the frequency from inefficient countries decreases. In the percentile-based approach, this trend, which is uniform at any citation level, is measured by the ep index that equals the Ptop 1%/Ptop 10% ratio. By using the ep index we demonstrate that EU research on fast-evolving technological topics is less efficient than the world average and that the EU is far from being able to compete with the most advanced countries. The ep index also shows that the USA is well ahead of the EU in both fast- and slow-evolving technologies, which suggests that the advantage of the USA over the EU in innovation is due to low research efficiency in the EU. In accord with some previous studies, our results show that the European Commission’s ongoing claims about the excellence of EU research are based on a wrong diagnosis. The EU must focus its research policy on the improvement of its inefficient research. Otherwise, the future of Europeans is at risk.  相似文献   
38.
The world has been turned upside down by a global health emergency caused by the Covid-19. Given the high contagiousness of the virus and the need to contain its spread, social distancing rules, self-isolation policies, and geographical lockdowns have been enforced globally. Over the pandemic emergency the majority of the planned in-person meetings and congresses of national and international anatomical societies have been postponed or canceled. It is unclear what the future holds, but times of crisis often present possibilities for re-thinking old ways to achieve a more critical approach. It has become increasingly clear that traditional in-person congress formats of scientific societies need to be reevaluated. Over the past year and a half, two types of congressional modalities have been trialed to address the challenge of the pandemic as far as scientific meetings are concerned: the fully virtual congress, in which case the conference program is live streamed to all of the attendees, and the hybrid congress, in which case some of the attendees physically participate at the congress's venue while others interact via a virtual platform. The current study set out to investigate the technical difficulties, social challenges, costs and sustainability, logistics and management issues linked to holding various types of congresses in the post-Covid world. Anatomical societies throughout the world are actively striving to reshape their response to the current global emergency and to uncover new types of conference modalities in the effort to keep scientific exchange alive and flourishing in the post-Covid era.  相似文献   
39.
In fall 2016, the Columbia-Cornell collaboration in the area of Slavic & East European resource coordination and sharing celebrated its sixth year. The author reviews particulars of the development, implementation, and function of this program as well as some of the challenges that face such cross-institutional efforts.  相似文献   
40.
We first report discovery of the spinel-garnet-orthopyroxene granulite with pure CO2 fluid inclusions from the Fuyun region of the late Paleozoic Altay orogenic belt in Central Asia, NW China. The rock is characterized by an assemblage of garnet, orthopyroxene, spinel, cordierite, biotite, plagioclase and quartz. Symplectites of orthopyroxene and spinel, and orthopyroxene and cordierite indicate decompression under UHT conditions. Mineral chemistry shows that the or-thopyroxenes have high XMg and A12O3 contents (up to 9.23 wt%). Biotites are enriched in TiO2 and XMg and are stable under granulite facies conditions. The garnet and quartz from the rock carry monophase fluid inclusions which show peak melting temperatures of around -56.7℃, indicating a pure CO2 species being presented during the ultrahigh-T metamorphism in the Altay orogenic belt. The inclusions homogenize into a liquid phase at temperatures around 15.3-23.8℃ translating into CO2 densities of the order of 0.86-0.88 g/cm3. Based on prelim  相似文献   
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