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Densification surveys in New South Wales coping with distortions / D.A. Kinlyside (1992)

Public Titre : Densification surveys in New South Wales coping with distortions Type de document : Monographie Auteurs : D.A. Kinlyside, Auteur Editeur : Kensington [Australie] : University of New South Wales Année de publication : 1992 Collection : Unisurv Report num. S-42 Importance : 202 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-0-85839-062-1 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux [Termes IGN] aberration instrumentale [Termes IGN] densification géodésique [Termes IGN] Nouvelle-Galles du Sud [Termes IGN] réseau géodésique [Termes IGN] transformation de coordonnées Index. décimale : 30.10 Systèmes de référence et réseaux géodésiques Résumé : (Auteur) This project reviews the traditional methods of estimating coordinates for points in horizontal geodetic densification networks within NSW (New South Wales). The primary control for these densification surveys consists of the station coordinates derived from the 1966 National Adjustment which have been assumed to be free of error. However, distortions in this primary control have become evident through the use of higher accuracy geodetic measurement techniques, such as lightwave EDM and space based positioning systems as well as improved methods of adjustment. The study quantifies the level of distortion in AGD66 within the confines of eastem NSW by comparing the existing coordinates with those estimated from a GPS network After transformation, the differences were found to be generally less than 0.5 metres, but systematic differences of about one metre appear in some areas of NSW. To demonstrate the effect of distortions propagating into secondary networks, a 300 x 300 km region in the central west of NSW was evaluated by combining all existing geodetic observations in a single adjustment. The theoretical aspects of several integration models, such as the weighted stations approach, were studied to determine their suitability for upgrading and densifying geodetic networks. The various models have certain compromises in either mathematical rigour or practicality. Numerical examples of the models are presented in which data is used ftom an existing primary and secondary densification network within the central west region of NSW. The problems involved in achieving and preserving the most accurate estimates for survey control coordinates in an operational environment are addressed. Particular attention is given to the least squares software capabilities, data management, network design and the analytical procedures currently used by the Land Information Centre, NSW Department of Lands. There is considerable scope for improvement in some of the present systems through the use of more effective data handling techniques. Future strategies for performing densification surveys in NSW will be significantly influenced by the trends in satellite surveying technology, the need for cadastral reform and the possibility of adopting a geocentric datum. The case for retaining the less accurate coordinates is compared with the acceptability of coordinate changes as new methods improve accuracy. Numéro de notice : 63991 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=61249

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
63991-01	30.10	Livre	Centre de documentation	Géodésie	Disponible