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Data update in a land information system / R.C. Mullin (1988)

Public Titre : Data update in a land information system Type de document : Monographie Auteurs : R.C. Mullin, Auteur Editeur : Kensington [Australie] : University of New South Wales Année de publication : 1988 Collection : Unisurv Report num. S-34 Importance : 170 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-0-85839-052-2 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées [Termes IGN] ArcInfo [Termes IGN] cadastre numérique [Termes IGN] données localisées [Termes IGN] jeu de données localisées [Termes IGN] mise à jour de base de données [Termes IGN] modèle conceptuel de données localisées [Termes IGN] système d'information géographique Résumé : (Auteur) This research deals with the problem of the on-going update of data exchanged in a land information network. In the past, major developments have been undertaken to enable the exchange of data between land information systems. Once a copy of a data set has been exchanged two questions must be faced : What happens to a copy of land information, collected and maintained by another agency, once it updates its information ? How are data updates propagated in a land information network ? A model of a land information network and the data update process have been developed. Based on these, a functional description of the database and software to perform data updating is presented. A prototype of the data update process was implemented using the ARC/INFO geographic information system. This was used to test four approaches to data updating. The four approaches are : bulk, block, incremental, and alert updates. A bulk update is performed by transferring a complete copy of an updated file and replacing the superseded file with the updated one. A block update requires that the data set be partitioned into blocks. When an update occurs, only the blocks which are affected need to be transferred. An incremental update approach records each feature which is added or deleted and transmits only the features needed to update the copy of the file. An alert is a marker indicating that an update has occurred. It can be placed in a file to warn a user that if he is active in an area containing markers, updated data is available. The four approaches to data updating have been tested using a cadastral data set. They have been shown to provide a variety of solutions to the update problem; covering a wide range of capability and performance requirements. Due to the variability of the data updating environment, it is not possible to develop specific criteria for the selection of optimum update policies. General criteria, which can be used in an iterative process, to reduce the number of available options and thus enable detailed investigations of the few most suitable approaches are presented. Numéro de notice : 63327 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=61194

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Code-barres	Cote	Support	Localisation	Section	Disponibilité
63327-01	37.10	Livre	Centre de documentation	Géomatique	Disponible