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Abstract

In an earlier exercise some demographic methods were reformulated for application in a scientometric context. Age-pyramids based on annual publication output and citation impact was supplemented by the change of the mean age of the publications in the h-core at any time. Although the method was introduced to shed some demographic–scientometric light on the career of individual researchers, the second component, i.e., the age dynamics of the h-core can however be applied to higher levels of aggregation as well. However, the found paradigmatic shapes and patterns do not only characterise individual careers and positions, but are also typical of life cycles and subject-specific peculiarities. In the present study, the proposed approach is used to visualise the careers of scientists active in different fields of the sciences and social sciences and notably the second component, the h-core dynamics, is extended to the analysis of scientific journals from the same fields. In addition to the dynamics of productivity and citation impact, the evolution of co-authorship patterns of the same scientists is studied to capture another facet of individual academic careers.

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Abstract  

Q-measures express the bridging function of nodes in a network subdivided into two groups. An approach to Q-measures in the context of weighted or valued directed networks is proposed. This new approach uses flow centrality as the main concept. Simple examples illustrate the definition.

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Abstract  

This study aims at detecting the role of individual journals and uncovering structural patterns of information flow among scientific journals in a cross-citation network, using different bibliometric indicators and statistical methods of data analysis. Beyond measuring the individual journals’ position within the communication network, we shed light on their cognitive background as well. Language barrier and lacking internationality proved one of the main hindrances for integration into the communication network. Moreover, some document types hinder journals from establishing self-links. Against our expectations, we have found a clear divergence between strongly interlinked and high-entropy journals. Furthermore, the analysis of strong links among different fields allows the detection of high-interdisciplinary journals.

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Abstract  

Nanoscience and technology (NST) is a young scientific and technological field that has generated great worldwide interest in the past two decades. Previous bibliometric analyses have unmistakably demonstrated the remarkable growth of the global NST literature. While almost all published research articles in NST are in English, increasingly a larger share of NST publications is published in the Chinese language. Perplexingly, Chinese is the only language — apart from English — that displays an ascendant trend in the NST literature. In this brief note, we explore and evaluate three arguments that could explain this phenomenon: coverage bias, language preference, and community formation.

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Abstract  

The objective of this study is to use a clustering algorithm based on journal cross-citation to validate and to improve the journal-based subject classification schemes. The cognitive structure based on the clustering is visualized by the journal cross-citation network and three kinds of representative journals in each cluster among the communication network have been detected and analyzed. As an existing reference system the 15-field subject classification by Glänzel and Schubert (Scientometrics 56:55–73, <cite>2003</cite>) has been compared with the clustering structure.

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A space X is of countable type (resp. subcountable type) if every compact subspace F of X is contained in a compact subspace K that is of countable character (resp. countable pseudocharacter) in X. In this paper, we mainly show that: (1) For a functionally Hausdorff space X, the free paratopological group FP(X)and the free abelian paratopological group AP(X) are of countable type if and only if X is discrete; (2) For a functionally Hausdorff space X, if the free abelian paratopological group AP(X) is of subcountable type then X has countable pseudocharacter. Moreover, we also show that, for an arbitrary Hausdorff μ-space X, if AP 2(X) or FP 2(X) is locally compact, then X is a topological sum of a compact space and a discrete space.

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