共查询到20条相似文献，搜索用时 15 毫秒
1.
A visual display of the most important universities in the world is the aim of this paper. It shows the topological characteristics and describes the web relationships among universities of different countries and continents. The first 1000 higher education institutions from the Ranking Web of World Universities were selected and their link relationships were obtained from Yahoo! Search. Network graphs and geographical maps were built from the search engine data. Social network analysis techniques were used to analyse and describe the structural properties of the whole of the network and its nodes. The results show that the world-class university network is constituted from national sub-networks that merge in a central core where the principal universities of each country pull their networks toward international link relationships. The United States dominates the world network, and within Europe the British and the German sub-networks stand out. 相似文献
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《Information processing & management》2023,60(2):103230
As a hot spot these years, cross-domain sentiment classification aims to learn a reliable classifier using labeled data from a source domain and evaluate the classifier on a target domain. In this vein, most approaches utilized domain adaptation that maps data from different domains into a common feature space. To further improve the model performance, several methods targeted to mine domain-specific information were proposed. However, most of them only utilized a limited part of domain-specific information. In this study, we first develop a method of extracting domain-specific words based on the topic information derived from topic models. Then, we propose a Topic Driven Adaptive Network (TDAN) for cross-domain sentiment classification. The network consists of two sub-networks: a semantics attention network and a domain-specific word attention network, the structures of which are based on transformers. These sub-networks take different forms of input and their outputs are fused as the feature vector. Experiments validate the effectiveness of our TDAN on sentiment classification across domains. Case studies also indicate that topic models have the potential to add value to cross-domain sentiment classification by discovering interpretable and low-dimensional subspaces. 相似文献
3.
Pekka Räsänen 《The Information Society》2013,29(4):219-228
This article examines to what extent the Nordic countries, which have been characterized as the world's leading information societies, show similar patterns of Internet use. The data consists of the Danish, Swedish, Norwegian, and Finnish sections of the European Social Survey 2002 ( n = 7539) and 2004 ( n = 7211). The similarities and differences in the Internet use are analyzed using sociodemographic and economic information. Temporal changes in the distribution of use between population groups and between countries are also examined. The findings indicate that there are clear disparities in the Internet use patterns, which have not evened out in the early 21st century. 相似文献
4.
In network science, the non-homogeneity of node degrees has been a concerning issue for study. Yet, with today''s modern web technologies, the traditional social communication topologies have evolved from node-central structures into online cycle-based communities, urgently requiring new network theories and tools. Switching the focus from node degrees to network cycles could reveal many interesting properties from the perspective of totally homogenous networks or sub-networks in a complex network, especially basic simplexes (cliques) such as links and triangles. Clearly, compared with node degrees, it is much more challenging to deal with network cycles. For studying the latter, a new clique vector-space framework is introduced in this paper, where the vector space with a basis consisting of links has a dimension equal to the number of links, that with a basis consisting of triangles has the dimension equal to the number of triangles and so on. These two vector spaces are related through a boundary operator, for example mapping the boundary of a triangle in one space to the sum of three links in the other space. Under the new framework, some important concepts and methodologies from algebraic topology, such as characteristic number, homology group and Betti number, will play a part in network science leading to foreseeable new research directions. As immediate applications, the paper illustrates some important characteristics affecting the collective behaviors of complex networks, some new cycle-dependent importance indexes of nodes and implications for network synchronization and brain-network analysis. 相似文献
5.
目前,京津冀区域医药产业已经形成一定规模的专利合作网络,该网络结构及其对医药企业专利产出的影响有待进一步探索。基于2011至2015年间的专利数据,以京津冀区域医药上市企业为搜索起点,依据组织间共同申请专利行为获取区域专利合作网络;在此基础上采用社会网络以及渗流理论分析方法解析该网络结构;最后结合上市企业年报数据实证该网络结构对上市企业专利产出的影响。结果显示京津冀区域医药产业专利合作网络整体以及北京地区子网和天津地区子网都是连通的,并且该网络整体的连通性主要由北京和天津地区所属结点来维持;该区域上市医药企业专利产出受到企业自身拥有的子网内以及子网间连接数量的正向影响,受其所属子网内部连通程度的负向影响。 相似文献
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7.
《Information processing & management》2001,37(1):147-161
This paper analyzes the features of the Swedish language from the viewpoint of mono- and cross-language information retrieval (CLIR). The study was motivated by the fact that Swedish is known poorly from the IR perspective. This paper shows that Swedish has unique features, in particular gender features, the use of fogemorphemes in the formation of compound words, and a high frequency of homographic words. Especially in dictionary-based CLIR, correct word normalization and compound splitting are essential. It was shown in this study, however, that publicly available morphological analysis tools used for normalization and compound splitting have pitfalls that might decrease the effectiveness of IR and CLIR. A comparative study was performed to test the degree of lexical ambiguity in Swedish, Finnish and English. The results suggest that part-of-speech tagging might be useful in Swedish IR due to the high frequency of homographic words. 相似文献
8.
网络计量学中的共链分析是一种新兴方法,也被认为是文献计量学中共引分析在网络文献的延伸。为了考察两者的实际关系,对专利技术公司和学术机构分别进行共链分析,将得到的多维尺度分析聚类图分别与专利共引和论文共引聚类图比较,得出共链分析与共引分析两种方法的相似性与差异性。同时发现,结合专利、论文、网页内容的共引与共链组合方法能够全方位地反映行业的情况,可以作为行业情报研究的有效方法之一。 相似文献
9.
情报学领域网络引文衰减规律研究——以三种核心期刊为例 总被引：3，自引：0，他引：3
随着互联网的普及,越来越多的学术论文将网络信息作为参考文献源,但这些网络引文相对于传统引文更加容易衰减。选取中文图书情报领域的三种核心期刊,对其1999-2008十年中发表的学术论文的网络引文进行分类处理,统计这些URL的衰减原因,计算中文图书情报领域核心期刊网络引文的半衰期,分析年际数量变化、域名和深度与其衰减规律的联系。并从URL特征、网络引文格式、网络信息来源等几个方面对缓解网络引文衰减提出6点建议。 相似文献
10.
《Information processing & management》2002,38(1):111-140
This research is a part of ongoing study to better understand citation analysis on the Web. It builds on Kleinberg's research (J. Kleinberg, R. Kumar, P. Raghavan, P. Rajagopalan, A. Tomkins, Invited survey at the International Conference on Combinatorics and Computing, 1999) that hyperlinks between web pages constitute a web graph structure and tries to classify different web graphs in the new coordinate space: out-degree, in-degree. The out-degree coordinate is defined as the number of outgoing web pages from a given web page. The in-degree coordinate is the number of web pages that point to a given web page. In this new coordinate space a metric is built to classify how close or far are different web graphs. Kleinberg's web algorithm (J. Kleinberg, Proceedings of the ACM-SIAM Symposium on Discrete Algorithms, 1998, pp. 668–677) on discovering “hub web pages” and “authorities web pages” is applied in this new coordinate space. Some very uncommon phenomenon has been discovered and new interesting results interpreted. This study does not look at enhancing web retrieval by adding context information. It only considers web hyperlinks as a source to analyze citations on the web. The author believes that understanding the underlying web page as a graph will help design better web algorithms, enhance retrieval and web performance, and recommends using graphs as a part of visual aid for search engine designers. 相似文献
11.
我国各学科学术期刊网络资源利用状况探析 总被引：2，自引：0，他引：2
为探究我国学术研究中对网络资源利用情况，本文采用信息计量学方法，利用国内各大学术期刊数据库，对我国学术期刊中的网络引文进行了全面、翔实的统计，利用大量的数据和图表分析了各学科学术期刊利用网络资源的差异，归结了网络引文发展过程中呈现的四个阶段。 相似文献
12.
Web 2.0环境下学术交流的社会网络分析 ——以博客为例 总被引：3，自引：0，他引：3
本文将Web 2.0环境下的学术交流网络作为研究对象,以图书馆学、情报学领域博客交流网络为例,从学者间交流和沟通的角度寻找并勾画出学者之间交流网络的结构,同时运用社会网络分析方法对相应的参数和指标进行中心度分析、小团体分析和小世界效应的验证,以期从完善结构的角度促进科研人员之间的信息沟通和交流. 相似文献
13.
Many operational IR indexes are non-normalized, i.e. no lemmatization or stemming techniques, etc. have been employed in indexing. This poses a challenge for dictionary-based cross-language retrieval (CLIR), because translations are mostly lemmas. In this study, we face the challenge of dictionary-based CLIR in a non-normalized index. We test two optional approaches: FCG (Frequent Case Generation) and s-gramming. The idea of FCG is to automatically generate the most frequent inflected forms for a given lemma. FCG has been tested in monolingual retrieval and has been shown to be a good method for inflected retrieval, especially for highly inflected languages. S-gramming is an approximate string matching technique (an extension of n-gramming). The language pairs in our tests were English–Finnish, English–Swedish, Swedish–Finnish and Finnish–Swedish. Both our approaches performed quite well, but the results varied depending on the language pair. S-gramming and FCG performed quite equally in all the other language pairs except Finnish–Swedish, where s-gramming outperformed FCG. 相似文献
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学术概念扩散的引文编年展示——以“临床试验中的利益冲突”为例 总被引：2，自引：0，他引：2
本文采用引文编年可视化程序,辨析学术界对于"临床试验中的利益冲突"这一概念理解和认识发展的脉络,对于其在学科领域之间扩散的路径进行梳理;识别其在时空中传播的特征,发现与此概念联系密切的研究论题。 相似文献
15.
[目的/意义]分析通证知识社区的知识分享网络结构,有助于把握区块链背景下的虚拟社区知识分享和传播规律。[方法/过程]以国内通证知识社区代表——币乎网为研究对象,通过网络爬虫方式获取币乎用户样本数据,采用社会网络分析和内容分析方法,运用UCINET工具对社区用户的知识分享网络进行网络特征分析。[结果/结论]样本网整体呈现出小世界效应和无标度网络特征;中心性高的核心用户对社区知识贡献和传播的影响力较高;通证激励有助于挖掘社区中的优质内容。 相似文献
16.
王保成 《中国科技期刊研究》2017,28(8):736-740
【目的】了解国内外图书馆学情报学期刊网站可用性是否存在差异及差异的来源。【方法】 以国内18种、国外21种高影响力的图书馆学情报学期刊网站为分析对象,采用可达性、可读性、网站响应速度和网站链接效果进行比较测评。【结果】 国内外图书馆学情报学期刊在网站可用性方面存在一定程度的差异,国内图书馆学情报学期刊网站在可用性方面有一定的改进空间。【结论】 国内期刊应当更多地从使用者的角度考虑网站建设,科技期刊网站的可用性应根据不同的语言进行有针对性的评价。 相似文献
17.
高校科研人员学术影响力综合评价在推动国家、高校和高校科研人员的整体综合全面发展中起着非常重要的作用。在科学2.0时代下,有必要将传统计量指标和替代计量指标结合起来实现更为全面有效的评价应用。鉴于此,本文基于ResearchGate网站平台抓取以北京工业大学科研人员为例的高校科研人员在网络媒体上呈现的影响力指标数据,并结合传统的引文计量指标数据,在数据分析中采用定性和定量相结合的方法,采用主成分分析和天际线的方法构建指标体系和评价模型,通过指标赋权作出综合评价。为科研人员学术影响力综合评价提供新视角,提出新思路,对具体评价结果进行解析,为完善高校教师科研评价体制的相应对策做出了重要贡献。 相似文献
18.
We study scaled group consensus problems of the first/second-order multi-agent dynamics under continuous/discrete-time settings. For a directed multi-agent network with finite sub-networks, the scaled group consensus is concerned with this case that all the sub-networks reach consensus, separately, while maintain the given ratios among the multiple consensus. First/second-order distributed protocols with continuous/discrete data are designed to solve the scaled group consensus problems, and then necessary and sufficient criteria are established to guarantee the agents’ states reaching the scaled group consensus asymptotically applying both algebraic and analytical tools. Finally, the effectiveness of the theoretical results are verified by several simulation examples. 相似文献
19.
为推动华东地区医产学研协同创新体系专业化建设,基于该区域内2004—2021年授权发明专利数据分析其医产学研合作发展状况,并以6年为时间窗格,利用社会网络分析方法分析其医产学研专利合作网络演化特征。结果表明：2004—2021年华东地区医产学研合作逐渐发展为规模较大、合作密度较高的网络,并在不同时期内呈现出较为明显的演化趋势,网络规模与合作频次不断增加,子网络数量和规模也呈现增长趋势;上海、江苏和浙江发挥排头兵作用,其中以浙江大学为首的高校和以中国科学院上海药物研究所为首的研究院的作用尤为突出,高校和研究所占据网络的核心地位并逐渐形成多中心合作子网络,而医药大企业并未起到重要的作用。根据研究发现,提出加快技术成果转化、激发核心节点带动作用、加强企业主导地位和提高医疗机构参与度等进一步推动华东地区医产学研协同创新发展的对策建议。 相似文献
20.
针对学术评价中多属性评价方法和组合评价方法众多,从而导致学术评价结果众多,评价公信力下降问题,优选多属性评价方法成为解决问题的较好途径。线性多属性评价相对成熟,非线性多属性评价的选取是首要问题,基于BP人工神经网络,以非线性多属性评价值作为输出,评价指标作为输入,通过训练人工神经网络,可以得到评价指标权重,进而和评价值评价指标的相关系数进行比较,通过检验非线性多属性评价方法的逻辑一致性来进行评价方法的选取。以JCR2017数学期刊为例,分别采用主成分分析、因子分析、TOPSIS进行评价,然后再基于BP人工神经网络模型进行选取。研究结果表明:非线性多属性评价方法的选择问题是学术评价的基础问题;BP人工神经网络可以用来辅助进行非线性评价方法的选取;采用BP人工神经网络辅助选取非线性评价方法必须具备一定的适用条件。 相似文献