1,720,986 research outputs found
Language Extensions for Semantic Integration of Deductive Databases
No full text. A language in support of semantic integration of deductive databases is proposed. The language allows one to construct mediators by extending logic programming with a suite of operators for composing programs and message passing features. The abstract semantics and implementation techniques of the extensions are discussed, and an example of integration of databases supporting libraries and departments is used to illustrate the usefulness of the approach. 1 Introduction At present, in the database area, much attention is devoted to studying the possibility of integrating different databases or, in any case, databases which have been developed within other projects, and that may be resident at different sites [19]. This issue has been largely studied in the past decades giving rise to approaches such as federated databases, multidatabases, interoperable databases or mediators. Here, we focus on integration of deductive databases. The problem is twofold: -- at the lower level, how to..
Maximum Entropy Inference for Geographical Information Systems
No full textAn immediate problem in approaching GIS (Geographic Information Systems) consists in giving a sufficiently agreed definition of what GIS actually are. For present purposes it seems reasonable to consider GIS as being characterized by a twofold nature. On the one hand, GIS consist of a technology used for certain purposes. From this perspective, the crucial issues in GIS research amount to computing problems, both on the hardware and software level. On the other hand, however, GIS research is increasingly more focussed on theoretical issues concerning the representation of geographic information. According to the latter point of view GIS problems include, at the very least, issues of knowledge representation and reasoning. In this chapter we investigate some of the consequences deriving from approaching GIS from the latter point of view. In particular, we will be insisting on the fact that its s‘conceptual side’, so to speak, commits GIS research to achieving scientific goals which happen to be closely related to some of those pursued in Artificial Intelligence (AI) research.3 In doing so, we adopt a perspective according to which GIS are essentially construed as artificial intelligent agents reasoning about a certain classes of natural environments
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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