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1.
An addendum and correction to “Mathematical properties of Q-measures” (vol. 7, issue 3, pp. 737–745)
《Journal of Informetrics》2014,8(3):486-490
A correction is provided for the proof of a theorem announced in (Rousseau et al., 2013). We show, moreover, that in a network subdivided into three or more subgroups there is at most one node with global Q-measure equal to one. In case there are two subgroups then it is possible to have two nodes with global Q-measure equal to one. This characterization leads to a graphical representation of networks having the maximum possible number of nodes with Q-measure equal to one. 相似文献
2.
We analyze whether preferential attachment in scientific coauthorship networks is different for authors with different forms of centrality. Using a complete database for the scientific specialty of research about “steel structures,” we show that betweenness centrality of an existing node is a significantly better predictor of preferential attachment by new entrants than degree or closeness centrality. During the growth of a network, preferential attachment shifts from (local) degree centrality to betweenness centrality as a global measure. An interpretation is that supervisors of PhD projects and postdocs broker between new entrants and the already existing network, and thus become focal to preferential attachment. Because of this mediation, scholarly networks can be expected to develop differently from networks which are predicated on preferential attachment to nodes with high degree centrality. 相似文献
3.
Joshua D. Atkinson 《Mass Communication and Society》2013,16(3):227-247
This research utilized multilevel analysis to explore interactive alternative media production in a new social movement network. Interviews with audiences, local producers, and global producers provide evidence of interactivity between local audiences and local producers and between local producers and global producers. The local audiences provided encouragement to local producers through face-to-face interactions that aided in the establishment of organizational support for the local producers but acted as a discursive closure that blinded local producers to potential problems with their alternative media. The global producers revealed that they received content-oriented interactions from audiences via e-mail, which corresponded with data collected from the local producers who claimed to interact with global producers via e-mail. The findings establish a preliminary model of interactivity in alternative media production that links research concerning new social movement networks and alternative media and builds on research concerning the decentralized structure of new social movement networks. 相似文献
4.
《Microprocessing and Microprogramming》1996,41(10):715-731
This paper presents a hybrid approach to distributed mutual exclusion in which two algorithms are combined such that one minimizes message traffic and the other minimizes time delay. In a hybrid approach, sites are divided into groups, and two different algorithms are used to resolve local (intra-group) and global (inter-group) conflicts. In this paper, we develop a hybrid distributed mutual exclusion algorithm which uses Singhal's dynamic information structure algorithm [15] as the local algorithm to minimize time delay and Maekawa's algorithm [7] as the global algorithm to minimize message traffic. Compared to Maekawa's algorithm which needs O(√N) messages, but two time units delay between successive executions of the Critical Section (CS) (where N is the number of sites in the system), the proposed hybrid algorithm can reduce message traffic by 52% and time delay by 29% at the same time. 相似文献
5.
《Journal of Informetrics》2022,16(2):101291
Bibliographic coupling (BC) and co-citation (CC) are the two most common citation-based coupling measures of similarity between scientific items. One can interpret these measures as second-neighbor relations distinguished by the direction of the citation: BC is a similarity between two citing items, whereas CC is that between two cited items. A previous study proposed a two-layer node split network that can emulate clusters of coupling measures in a computationally efficient manner; however, the lack of intralayer links makes it impossible to obtain exact similarities. Here, we propose novel methods to estimate intralayer similarity on a node split network using personalized PageRank (PPR) and neural embedding (EMB). We demonstrate that PPR is strongly correlated with the coupling measures. Moreover, our proposed method can yield precise similarities between items even if they are distant from each other. We also show that many links with high similarity are missing in the original BC/CC network, which suggests that it is essential to consider long-range similarities. Comparative experiments on global and local edge sampling suggest that local sampling is stable for PPR in node split networks. This analysis offers valuable insights into the process of searching for significantly related items regarding each coupling measure. 相似文献
6.
《Journal of Informetrics》2023,17(1):101358
Extant studies suggest that the proximity between the researchers and their structural positioning in the collaboration network may influence productivity and performance in collaboration research. In this paper, we analyze the co-authorship networks of the three countries, viz. the USA, China, and India, constructed in consecutive non-overlapping 5-year long time windows from bibliometric data of research papers published in the past decade in the rapidly evolving area of Artificial Intelligence and Machine Learning (AI&ML). Our analysis relies on the observations ensued from a comparison of the statistical properties of the evolving networks. We consider macro-level network properties which describe the global characteristics, such as degree distribution, assortativity, and large-scale cohesion etc., as well as micro-level properties associated with the actors who have assumed central positions, defining a core in the network assembly with respect to closeness centrality measure. For the analysis of the core actors, who are well connected with a large number of other actors, we consider share of their affiliations with domestic institutes. We find dominant representation of domestic affiliations of the core actors for high productivity cases, such as China in the second time window and the USA in the first and second both. Our study, therefore, suggests that the domestic affiliation of the core actors, who could access network resources more efficiently than other actors, influences and catalyzes the collaborative research. 相似文献
7.
Research carried out in 2011 in Kirinyaga district, Kenya, shows how sense-making theory and methodology can be used to assess the use of local agricultural and external knowledge by small-scale farmers and its effects on small-scale agriculture. Two knowledge systems, the local knowledge system and the external or scientific knowledge system, are considered dominant. The two systems can be synergistic and small-scale farmers have mixed them in their farming activities. Blending systems improve communication, livelihoods, and economies within local communities, and increases their participation in development. Data were collected in focus group discussions with farmers' groups and interviews with individual farmers. Results show that most farmers in Kirinyaga use external agricultural information in their farming practices. A significant number use combined external agricultural information and local knowledge, which forms a third knowledge system. This third system requires the validation of the farmers' innovations and documentation of the knowledge for wider dissemination. Information providers should adopt policies that promote the use of the three knowledge systems by small-scale farmers. 相似文献
8.
Collaboration networks have primarily been studied in developed economies. In this paper, we present a comprehensive analysis of co-inventor networks in a small but thriving OECD economy in Latin America: Chile. Using a dataset for patents granted in the country between 1989 and 2018, we study a variety of statistical properties for five different co-inventor networks. We show that these networks exhibit power-law, small-world, and preferential attachment properties, all of which have been used to describe networks in more advanced economies. We also highlight some apparent differences in collaboration patterns between networks (and inventors) and we reveal the precarious nature of the network of local inventors by confirming the community structure property. Evidence for strong positive autocorrelation between highly and lowly productive inventors is presented via methods used in spatial econometrics. Our results show that the inventor system in Chile is highly fragmented, which emphasizes the need for strong government intervention in steering research funding, and for more collaboration between inventors, especially local ones. 相似文献
9.
There is minimal research on the cross-cultural needs, priorities, and behaviors of international participants immersed in contemporary culturally alien information environments. Through a quantitative analysis of Internet use patterns of international teaching assistants (ITA) studying in graduate school at a representative university in the United States, the authors discover communication-information convergences in ITAs’ use of the Internet as a “glocal” network, connecting the “global” and “local” dimensions in their everyday lives. The paper identifies dual functions of the Internet considered meaningful to the ITAs in the diaspora, namely: (1) to engage in various communication activities with friends and family in their home countries (the “global”), thereby providing psychological comfort and overcoming social isolation; and (2) to conduct information gathering activities that establish coping mechanisms for ITAs in their new homes in the United States (the “local”). The paper presents empirical data highlighting correlations between communication and information intersections in ITAs’ use of the Internet. Findings extend past Internet research and user studies in traditional communication and information research, which only alluded to these communication-information convergence processes, to better understand how international people use the Internet in present-day cross-cultural contexts of interaction. 相似文献
10.
How does the collaboration network of researchers coalesce around a scientific topic? What sort of social restructuring occurs as a new field develops? Previous empirical explorations of these questions have examined the evolution of co-authorship networks associated with several fields of science, each noting a characteristic shift in network structure as fields develop. Historically, however, such studies have tended to rely on manually annotated datasets and therefore only consider a handful of disciplines, calling into question the universality of the observed structural signature. To overcome this limitation and test the robustness of this phenomenon, we use a comprehensive dataset of over 189,000 scientific articles and develop a framework for partitioning articles and their authors into coherent, semantically related groups representing scientific fields of varying size and specificity. We then use the resulting population of fields to study the structure of evolving co-authorship networks. Consistent with earlier findings, we observe a global topological transition as the co-authorship networks coalesce from a disjointed aggregate into a dense giant connected component that dominates the network. We validate these results using a separate, complimentary corpus of scientific articles, and, overall, we find that the previously reported characteristic structural evolution of a scientific field's associated co-authorship network is robust across a large number of scientific fields of varying size, scope, and specificity. Additionally, the framework developed in this study may be used in other scientometric contexts in order to extend studies to compare across a larger range of scientific disciplines. 相似文献
11.
《Government Information Quarterly》2018,35(1):109-122
Despite the expectation that social media use in the public sector contributes to enhancing government responsiveness to citizens, few empirical studies exist on whether social media use actually leads to more responsive public administration in practice and how social media are used by governments to build citizen-centric governance. The purpose of this study is to examine what roles are played by mayors and public officials in social media networks to increase government responsiveness. Thus, we adopt social network analysis (SNA) to the Twitter network of public services as well as carry out a case study on interactions among the mayor, local government, and citizens via Twitter in Seoul, Korea. The research findings show that the mayor of Seoul plays the most important role as a bridging hub in the Twitter network. Specifically, the mayor serves as a bridge between different clusters of citizens and public officials as well as a hub for the most connected users in the network. The mayor's role as a bridging hub in the Twitter network contributes to enhancing government responsiveness by making possible to overcome the disconnection between citizens and the local government, and information asymmetry among the mayor, public officials, and citizens. 相似文献
12.
浅谈图书馆网络的管理 总被引：2，自引：0，他引：2
图书馆是学校的数据信息中心,网络是否能正常发挥作用还要看网络的管理。图书馆网络管理与单机管理有重要区别,需要排除网络在管理中的一切障碍,同时要积极防范外界对图书馆网络的破坏和攻击。 相似文献
13.
本文以新浪微博"时尚"标签下的用户作为研究样本,基于样本用户间以及整个新浪微博用户间的关注关系分别构建了"相互关注"网络与"共同关注"网络,运用社会网络分析法揭示了微博中该标签领域的权威人物及网络成员之间的关系,并进一步对比分析了"相互关注"和"共同关注"的网络属性差异以及差异产生的原因。此外,本文还分析了表征人气的粉丝数、博文转发数、博文评论数这三个指标之间的相关性及其与社会网络分析指标的相关性,对微博核心用户的确定问题进行了讨论。 相似文献
14.
科学研究的目的在于创造知识,并应用理论成果解决我国社会、经济、文化等发展中的实际问题。将论文发表在国际期刊上可以让更多的国际同行了解我国最新的科研成果,为我国获得更多的国际影响力,所以在过去二十多年里SCI论文成为我国科研考核的一个重要指标。在这种科研评价导向下,我国学者发表的国际论文数量已居世界第一位,而大量来自国内同行的引用使得我国国际论文的被引量排名世界第二。本文提取1990至2015年Web of Science论文及其引文的数据,分析不同国家、不同学科在国家层次的自引情况,并在不同国家、不同学科之间进行比较。研究发现,在排除国内同行的自引后,我国国际论文的真实国际影响力仍然有限,除了临床医学和物理等少数学科外,其他学科仍然低于全球平均水平。 相似文献
15.
Andrea Kavanaugh Ankit Ahuja Samah Gad Sloane Neidig Manuel A. Pérez-Quiñones Naren Ramakrishnan John Tedesco 《Government Information Quarterly》2014
Being able to debate, reflect, form opinions, consider counter evidence and make informed decisions is a foundation of civic life in democratic societies. Government benefits from broad participation in collective decision making in terms of sustainable outcomes (e.g., greater consensus) and quality of life in our cities and communities. These collective decision making capabilities are undermined by a strange combination of diminishing (or extinct) local print media, especially local newspapers, and by its obverse, a plethora of information and communication opportunities that are scattered across numerous disparate and decentralized websites and resources (e.g., webpages, RSS feeds, social network software, email, listservs, podcasts, tweets). To address this problem, a number of news aggregators have emerged that capture local content from dispersed sites. To facilitate civic engagement, these sites also need to support social interaction and information exchange. In this paper we review the state of the art in local news aggregation in the U.S. and their support for social affordances (social trust, networks and interaction) that are essential to civic participation. We present a system we call the Virtual Town Square (VTS) that we have developed for local news aggregation that supports social affordances. We summarize briefly the design strategies and techniques (e.g., algorithms) we used to cluster topics and user generated content derived from existing local sources. This system should lead to a replicable model for other U.S. communities. 相似文献
16.
This study examines global collaborative creativity through patentometrics and social network analysis. Because patents are a direct output of innovative activities, cross-border patents are used to analyze the trend of global collaborative creativity. The results show linear growth of cross-border patents, while numerous inventors have grown exponentially for collaborative creativity. The number of inventors for global collaborative creativity trends have increased more rapidly than the number of patents. The network for global collaborative creativity is denser and shows a growing trend over a five-year interval. Both observed and cosine-normalized numbers of k-cores in global collaborative creativity show a growing trend, while the cosine-normalized k-cores increase slowly compared to the observed one. Similarly, the social network analysis confirms a growing network of global collaborative creativity, which is dense despite its small degree of growth. This study also found that high values of “betweenness” tend to spread from core countries to periphery countries. Collaborative creativity has globalized but remains concentrated in core countries such as the U.S., the UK, France, Germany, and Canada. 相似文献
17.
Julie Uldam 《广播与电子媒介杂志》2013,57(3):431-434
This study examines the attitudes and the selection criteria of U.S. television journalists toward international news. Q factor analysis of 3I journalists from major national networks and local television stations reveals that journalists select international news based on market demands and local relevance. The findings strikingly delineate along the line between network versus local television. Network journalists manifest a global view, selecting international news with diverse themes, while local television journalists adopt a more pragmatic stance due to business pressures and audience demands, choosing international news with a local angle. All, however, emphasize timeliness and U.S. involvement in news selection. 相似文献
18.
《图书馆管理杂志》2013,53(3):93-107
Summary Despite numerous cooperative collection development endeavors, the building of library collections has remained a highly individual and local practice. The physicality of bound volumes has posed a distinct limitation on our ability to share collections, although libraries have made huge strides in recent years. Electronic resources and the ability to digitize our physical holdings offer the potential to redirect our investments in collection building to the creation of a global network that would serve an international community of scholars. By facilitating the creation of discipline-based portals to knowledge resources, librarians can channel their efforts to the benefit of many without sacrificing the quality of local relationships. To accomplish this, libraries need to develop collectively built and managed Web sites that supplant the need for autonomous, selector-created “webliographies” and that greatly expand the number of sources that can be identified and described. Selectors, freed of the individual responsibility to shoulder the increasingly heavy and ultimately unsustainable load of tracking a proliferation of resources in a variety of formats and states of publication, can turn their attention to the capture of more elusive, but important, material; to more detailed evaluation of the use of information resources; toward improvements in the user interface of portals; or toward the transformation of scholarly communication, with the discipline-based portal serving as a magnet for attracting new forms of scholarly thought and research. 相似文献
19.
高校图书馆座位资源配置的帕累托优化解决方案 总被引：1，自引：0，他引：1
20.
Little is known about how public sector organisations capitalise on the potential of social networking sites (SNSs) as communication channels. Previous research is short on theoretical models and managerial insights into the success of local governments' online communication strategies. The purpose of this study is to explore how successfully local governments utilise SNSs for managing their external communication with citizens. Using a multi-method analysis of 15,941 posts and 19,290 comments on the Facebook pages of the 25 largest German cities, we make five contributions to research and practice. First, we analyse the properties and topics of government posts to draw a rich picture of how local governments use Facebook as a communications channel. Second, we conceptualise success in governments' online communications in terms of the frequency and polarity of citizens' reactions, which we use for third, evaluating government communication behaviour in SNSs. Fourth, we identify which benefits SNSs offer that traditional communication channels do not provide. Fifth, we offer guidelines for improving the online communication strategies of local governments using SNSs. 相似文献