Search (5 results, page 1 of 1)

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Abstract

This article describes the latest development of a generic approach to detecting and visualizing emerging trends and transient patterns in scientific literature. The work makes substantial theoretical and methodological contributions to progressive knowledge domain visualization. A specialty is conceptualized and visualized as a time-variant duality between two fundamental concepts in information science: research fronts and intellectual bases. A research front is defined as an emergent and transient grouping of concepts and underlying research issues. The intellectual base of a research front is its citation and co-citation footprint in scientific literature - an evolving network of scientific publications cited by research-front concepts. Kleinberg's (2002) burst-detection algorithm is adapted to identify emergent research-front concepts. Freeman's (1979) betweenness centrality metric is used to highlight potential pivotal points of paradigm shift over time. Two complementary visualization views are designed and implemented: cluster views and time-zone views. The contributions of the approach are that (a) the nature of an intellectual base is algorithmically and temporally identified by emergent research-front terms, (b) the value of a co-citation cluster is explicitly interpreted in terms of research-front concepts, and (c) visually prominent and algorithmically detected pivotal points substantially reduce the complexity of a visualized network. The modeling and visualization process is implemented in CiteSpace II, a Java application, and applied to the analysis of two research fields: mass extinction (1981-2004) and terrorism (1990-2003). Prominent trends and pivotal points in visualized networks were verified in collaboration with domain experts, who are the authors of pivotal-point articles. Practical implications of the work are discussed. A number of challenges and opportunities for future studies are identified.

Date

22. 7.2006 16:11:05

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Abstract

Aggregated journal-journal citation networks based on the Journal Citation Reports 2004 of the Science Citation Index (5,968 journals) and the Social Science Citation Index (1,712 journals) are made accessible from the perspective of any of these journals. A vector-space model Is used for normalization, and the results are brought online at http://www.leydesdorff.net/jcr04 as input files for the visualization program Pajek. The user is thus able to analyze the citation environment in terms of links and graphs. Furthermore, the local impact of a journal is defined as its share of the total citations in the specific journal's citation environments; the vertical size of the nodes is varied proportionally to this citation impact. The horizontal size of each node can be used to provide the same information after correction for within-journal (self-)citations. In the "citing" environment, the equivalents of this measure can be considered as a citation activity index which maps how the relevant journal environment is perceived by the collective of authors of a given journal. As a policy application, the mechanism of Interdisciplinary developments among the sciences is elaborated for the case of nanotechnology journals.

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Abstract

We propose an approach to visualizing the scientific world and its evolution by constructing minimum spanning trees (MSTs) and a two-dimensional map of scientific journals using the database of the Science Citation Index (SCI) during 1994-2001. The structures of constructed MSTs are consistent with the sorting of SCI categories. The map of science is constructed based on our MST results. Such a map shows the relation among various knowledge clusters and their citation properties. The temporal evolution of the scientific world can also be delineated in the map. In particular, this map clearly shows a linear structure of the scientific world, which contains three major domains including physical sciences, life sciences, and medical sciences. The interaction of various knowledge fields can be clearly seen from this scientific world map. This approach can be applied to various levels of knowledge domains.

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Abstract

"Im 21. Jahrhundert ist die entscheidende Herausforderung an Informationsdienstleister nicht, Informationen zugänglich, sondern sie optimal nutzbar zu machen", sagt Sabine Brünger-Weilandt, Geschäftsführerin von FIZ Karlsruhe, das den Online-Dienst STN International in internationaler Kooperation betreibt. Informationsprofis, so Brünger-Weilandt weiter, bräuchten hockentwickelte Software für strategisches Informationsmanagement. Als "Antwort auf diesen Bedarf" hat STN International eine neue Software zur Analyse und Visualisierung (A&V) von Rechercheergebnissen aus STN-Datenbanken entwickelt. STN® AnaVistT(TM) wurde auf der DGI Online-Tagung Ende Mai in Frankfurt am Main und auf Benutzertreffen in Frankfurt am Main, München und Essen vorgestellt. Seit 18. Juli 2005 ist das neue A&V-Werkzeug für die öffentliche Nutzung freigegeben (www.stn-international.de).
Die wichtigsten Funktionen von STN AnaVist sind: - Inhalte aus mehreren Datenbanken sind gleichzeitig auswertbar - Nutzer können Daten aus unterschiedlichen Ouellen suchen, analysieren und visualisieren, u.a. aus der Chemiedatenbank CAplusSM, der Patentdatenbank PCTFULL, und US-amerikanischen Volltextdatenbanken. - Einzigartige Beziehungen zwischen Datenelementen-nur STN AnaVist bietet die Möglichkeit, Beziehungen zwischen sieben unterschiedlichen Feldern aus Datenbankdokumenten - z.B., Firmen, Erfindern, Veröffentlichungsjahren und Konzepten-darzustellen. - Gruppierung und Bereinigung von Daten - vor der Analyse werden Firmen und ihre unterschiedlichen Namensvarianten von einem "Company Name Thesaurus" zusammengefasst. - Konzept-Standardisierung - Durch das CAS-Vokabular werden Fachbegriffe datenbankübergreifend standardisiert, so dass weniger Streuung auftritt. - Interaktive Präsentation der Beziehungen zwischen Daten und Diagrammenwährend der Auswertung können Daten zum besseren Erkennen der Beziehungen farblich hervorgehoben werden. - Flexible Erstellung der auszuwertenden Rechercheergebnisse - Rechercheergebnisse, die als Ausgangsdatensatz für die Analyse verwendet werden sollen, können auf zwei Arten gewonnen werden: zum einen über die in STN® AnaVist(TM) integrierte Konzept-Suchfunktion, zum anderen durch problemlose Übernahme von Suchergebnissen aus der bewährten Software STN Express® with Discover! TM Analysis Edition, Version 8.0

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Abstract

Die Zahl von Netzwerkakteuren steigt ebenso beständig wie die Menge an Inhalten, die von denselbigen produziert wird. Wir stellen visuell orientierte explorative Werkzeuge vor, die bisher unsichtbare Netzwerkprozesse und Zusammenhänge aus der Vogelperspektive darstellen sollen. Anhand unseres Projekts "MemeMapper" untersuchen wir weiters, wie wir als Designer und Entwickler dazu beitragen können, dass sich Nutzer effektiver informieren und an der Produktion von Inhalten in ihrem Netzwerk beteiligen können.