1,720,958 research outputs found
La derivazione cartografica in ambiente GIS della CTR numerica della Regione Sardegna alla scala 1:50.000
No full textPUNTI GEODETICI FONDAMENTALI DELLA SARDEGNA: COORDINATE NEI SISTEMI DI RIFERIMENTO NAZIONALE E INTERNAZIONALI
No full textMultiscale representation: a data generalization workflow and quality evaluation experience in GIS enviroment
No full textConcerning geographic data representation, what a user need is specific tools for the representation and evaluation of the data on which the decision process relies. In cartographic applications, users need to deal with maps of the same geographic region at different levels of abstractions. Usually it’s used to maintain one database per level detail; a multiscale representation GIS would allow storing all original geographical information in a single database, and enforce the consistency of the different representations through appropriate, automatic generalization processes.
In this paper we deal with the problem of geographic data generalization, beginning from a generalization workflow by improving specific routines.
To aim the goals of the generalization process, we used the ESRI ArcGIS 8.1 platform. Inside this enviroment it have been implemented some generalization functionalities by improving appropriate ruotines in Visual Basic language. After a presentation of the generalization workflow, all cartographic constraints, of geometric, topological and semantic nature, governing the generalization process, are specified. In the next step these constraints will be translated into tools for assessing the need and the quality of generalization solutions. These tools are associated with a particular data model. For that data model the constraints can be best translated to measures and generalization algorithms and parameterized. This framework is based on constraints that are used to control the process and represent the user requirements in a way the system can manage to reach a quality close to these requirements; it reflects the idea that more than one acceptable solution may exist to a given generalization problem. The goal was the production of a topographic map at scale 1:50000, 1:100000 and 1:250000 from the “Carta Tecnica Regionale”, CTR, (official regional cartography) of the “Regione Autonoma della Sardegna”, RAS, (Regional Administration of Sardinia), at scale 1:10000, in a GIS environment.
According with the official national and international standards, we provide the definition of the characteristics and associated quality evaluation tool to be used in order to validate the geographic data
Trattamento della CTR numerica della Regione Sardegna per la organizzazione dei dati geografici nel SIT
No full textLa generalizzazione cartografica automatica in ambiente GIS
No full textThe paper shows the results achieved by the research group of the University of Cagliari in the field mapping automatic generalization. Particularly the work concerned this objectives:
- study of a model for the generalization of geographical data from 1:10.000 to 1:25.000, 1:50.000, 1:100.000 and 1:250.000;
- development of the model for automatic generalization;
- test on digital cartography;
- verification of the results achieved in terms of precision, of comprehensibility and truthfulness.
The process is mostly carried out according to auto and semi-automatic procedures within an ESRI ArcGIS software platform, version 8.1
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
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