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Least squares support vector machine model for coordinate transformation / Yao Yevenyo Ziggah in Geodesy and cartography, vol 45 n° 1 (2019)
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Titre : Least squares support vector machine model for coordinate transformation Type de document : Article/Communication Auteurs : Yao Yevenyo Ziggah, Auteur Année de publication : 2019 Article en page(s) : pp 16 - 27 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] Ghana
[Termes IGN] méthode des moindres carrés
[Termes IGN] projection conforme
[Termes IGN] résidu
[Termes IGN] séparateur à vaste marge
[Termes IGN] transformation affine
[Termes IGN] transformation de coordonnéesRésumé : (auteur) In coordinate transformation, the main purpose is to provide a mathematical relationship between coordinates related to different geodetic reference frames. This gives the geospatial professionals the opportunity to link different datums together. Review of previous studies indicates that empirical and soft computing models have been proposed in recent times for coordinate transformation. The main aim of this study is to present the applicability and performance of Least Squares Support Vector Machine (LS-SVM) which is an extension of the Support Vector Machine (SVM) for coordinate transformation. For comparison purpose, the SVM and the widely used Backpropagation Neural Network (BPNN), Radial Basis Function Neural Network (RBFNN), 2D conformal and affine methods were also employed. To assess how well the transformation results fit the observed data, the root mean square of the residual horizontal distances and standard deviation were used. From the results obtained, the LS-SVM and RBFNN had comparable results and were better than the other methods. The overall statistical findings produced by LS-SVM met the accuracy requirement for cadastral surveying applications in Ghana. To this end, the proposed LS-SVM is known to possess promising predictive capabilities and could efficiently be used as a supplementary technique for coordinate transformation. Numéro de notice : A2019-482 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.3846/gac.2019.6053 Date de publication en ligne : 17/04/2019 En ligne : https://doi.org/10.3846/gac.2019.6053 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93629
in Geodesy and cartography > vol 45 n° 1 (2019) . - pp 16 - 27[article]Les représentations planes cylindriques de la terre / Françoise Duquenne in XYZ, n° 157 (décembre 2018 - février 2019)
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Titre : Les représentations planes cylindriques de la terre Type de document : Article/Communication Auteurs : Françoise Duquenne , Auteur Année de publication : 2018 Article en page(s) : pp 45 - 50 Note générale : bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Projections
[Termes IGN] convergence des méridiens
[Termes IGN] facteur d'échelle
[Termes IGN] latitude
[Termes IGN] ligne géodésique
[Termes IGN] module linéaire
[Termes IGN] projection cylindrique
[Termes IGN] projection Universal Transverse MercatorRésumé : (auteur) The purpose of this paper is to recall th fundamental concept of the plane cylindrical representations of the earth, especially those which are conformal. Amongst these, the most known and used projection throughout the world is the Universal Transverse Mercator (UTM). The algorithm of calculation presented here, developed by French IGN, has the advantage of using exact formulas and not limited developments like many others, and thus of beeing easily computerized. Numéro de notice : A2018-534 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91579
in XYZ > n° 157 (décembre 2018 - février 2019) . - pp 45 - 50[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 112-2018041 RAB Revue Centre de documentation En réserve L003 Disponible On determining orthometric heights from a corrector surface model based on leveling observations, GNSS, and a geoid model / Su-Kyung Kim in Journal of applied geodesy, vol 12 n° 4 (October 2018)
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Titre : On determining orthometric heights from a corrector surface model based on leveling observations, GNSS, and a geoid model Type de document : Article/Communication Auteurs : Su-Kyung Kim, Auteur ; Jihye Park, Auteur ; Daniel T. Gillins, Auteur ; Michael Dennis, Auteur Année de publication : 2018 Article en page(s) : pp 323 - 333 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] altitude orthométrique
[Termes IGN] coefficient de corrélation
[Termes IGN] compensation de coordonnées
[Termes IGN] erreur en position
[Termes IGN] géoïde gravimétrique
[Termes IGN] hauteur ellipsoïdale
[Termes IGN] North American Vertical Datum 1988
[Termes IGN] Oregon (Etats-Unis)
[Termes IGN] système de référence altimétrique
[Vedettes matières IGN] AltimétrieRésumé : (auteur) Leveling is a traditional geodetic surveying technique that has been used to realize a vertical datum. However, this technique is time consuming and prone to accumulate errors, where it relies on starting from one station with a known orthometric height. Establishing orthometric heights using Global Navigation Satellite Systems (GNSS) and a geoid model has been suggested [14], but this approach may involve less precisions than the direct measurements from leveling. In this study, an experimental study is presented to adjust the highly accurate leveling observations along with orthometric heights derived from GNSS observations and a geoid model. For the geoid model, the National Geodetic Survey’s gravimetric geoid model (TxGEOID16B) and hybrid geoid model (GEOID12B) were applied. Uncertainties in the leveled height differences, GNSS derived heights, and the geoid models were modeled, and a combined adjustment was implemented to construct the optimal combination of orthometric, ellipsoidal, and geoid height at each mark. As a result, the discrepancy from the published orthometric heights and the CSM (Corrector Surface Model) based adjusted orthometric heights with GEOID12B showed a mean and RMS of -8.5 mm and 16.6 mm, respectively, while TxGEOID16B had a mean and RMS of 28.9 mm and 34.6 mm, respectively. It should be emphasized that this approach was not influenced by the geodetic distribution of the stations where the correlation coefficients between the distance from the center of the surveying network and the discrepancy from the published heights using TxGEOID16B and GEOID12B are 0.03 and 0.36, respectively. Numéro de notice : A2018-672 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1515/jag-2018-0014 Date de publication en ligne : 29/08/2018 En ligne : https://doi.org/10.1515/jag-2018-0014 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91004
in Journal of applied geodesy > vol 12 n° 4 (October 2018) . - pp 323 - 333[article]The problem of double longitudes on Glavač’s map / Marina Viličić in Cartographic journal (the), Vol 55 n° 3 (August 2018)
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Titre : The problem of double longitudes on Glavač’s map Type de document : Article/Communication Auteurs : Marina Viličić, Auteur ; Miljenko Lapaine, Auteur Année de publication : 2018 Article en page(s) : pp 217 - 234 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cartographie ancienne
[Termes IGN] carte ancienne
[Termes IGN] Croatie
[Termes IGN] dix-septième siècle
[Termes IGN] longitude
[Termes IGN] méridien
[Termes IGN] régression linéaireRésumé : (Auteur) Stjepan Glavač (1627-1680) produced a map of Croatia dated 1673, on which two meridians appear twice, 40°/51° and 41°/52°. The only written source regarding Glavač’s map is the dedication, which forms an integral part of the map. It does not say which prime meridians Glavač relied on, so in our research we attempted to establish what those prime meridians might have been. We approached the problem of the double longitudes using linear regression, through which we wanted to examine the relation of Glavač’s longitudes to modern values. An essential part of the research was a comparison of Glavač’s map with maps by his predecessors and contemporaries which show approximately the same prime meridians. The maps analysed, with their written values for the longitudes of certain places, indicated that the selection of prime meridians at that time was not entirely reliable. A further problem seemed to be the knowledge of the position of islands chosen as points of departure for longitudes. We concluded that the points of departure for Glavač’s dual longitudes were Palma, one of the Canary Islands, and the islands of Corvo and Flores in the Azores. Numéro de notice : A2018-517 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00087041.2017.1386343 Date de publication en ligne : 18/10/2018 En ligne : https://doi.org/10.1080/00087041.2017.1386343 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91322
in Cartographic journal (the) > Vol 55 n° 3 (August 2018) . - pp 217 - 234[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 030-2018031 RAB Revue Centre de documentation En réserve L003 Disponible The triangulated affine transformation parameters and barycentric coordinates of Turkish Permanent GPS Network / Kutubuddin Ansari in Survey review, vol 50 n° 362 (August 2018)
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Titre : The triangulated affine transformation parameters and barycentric coordinates of Turkish Permanent GPS Network Type de document : Article/Communication Auteurs : Kutubuddin Ansari, Auteur ; Ozsen Corumluoglu, Auteur ; Payal Verma, Auteur Année de publication : 2018 Article en page(s) : pp 412 - 415 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] barycentre
[Termes IGN] Eurasia Fixed Reference Frame
[Termes IGN] réseau géodésique permanent
[Termes IGN] transformation affine
[Termes IGN] transformation de coordonnées
[Termes IGN] TurquieRésumé : (Auteur) There are several computational approaches and methods to produce the complete solutions of geometry problems and they give sufficient computational strength for geodetic networks. Every approach and method has their advantages and drawbacks. Barycentric coordinates, also called areal coordinates, provide a new knock approach for geometry problems of such networks. This coordinate system offers triangular finite elements which are quite different from the usual Cartesian coordinate system. Actually, barycentric coordinates are a natural system of coordinates for the affine geometry. The modified approach for the affine transformation and barycentric coordinate system has been introduced and discussed, respectively in the study whether the affine transformation improves the results deteriorated by geometry of a GPS network. For this aim, general affine transformation of six-parameters between Eurasia Fixed Reference Frame (EUREF) and International Terrestrial Reference Frame (ITRF) for Turkish Permanent Global Positioning System Network (TPGN) has been computed. The affine transformation results show that the effects of the first and second translation parameters are in negative and positive directions, respectively. The third and sixth parameters are almost constant, on the other hand the fourth and fifth have a very small positive effect. Additionally, three triangular networks of GPS stations, at different locations in Turkey as a numerical example of barycentric coordinates, have also been presented. In the numerical example, the coordinate values of EUREF and ITRF have some differences after the decimal point, but the barycentric coordinates have very small amount of differences (sixth digit after decimal) which proves that the modified approach is meaningful. Numéro de notice : A2018-447 Affiliation des auteurs : non IGN Thématique : INFORMATIQUE/POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/00396265.2017.1297016 Date de publication en ligne : 05/03/2017 En ligne : https://doi.org/10.1080/00396265.2017.1297016 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91032
in Survey review > vol 50 n° 362 (August 2018) . - pp 412 - 415[article]Extension de fuseau de la projection de Mercator Transverse : Application au réseau géodésique primordial Algérien / Bachir Gourine in XYZ, n° 155 (juin - août 2018)PermalinkLe CNIG et les références géodésiques / Françoise Duquenne in XYZ, n° 154 (mars - mai 2018)PermalinkLes systèmes de référence terrestre et leurs réalisations : cas des territoires français / Françoise Duquenne in XYZ, n° 154 (mars - mai 2018)PermalinkPermalinkAssessing the quality of GEOID12B model through field surveys / Ahmed F. Elaksher in Journal of applied geodesy, vol 12 n° 1 (January 2018)PermalinkHeight biases of SRTM DEM related to EGM96: from a global perspective to regional practice / A. Üstün in Survey review, vol 50 n° 358 (January 2018)PermalinkIntroduction to multiple regression equations in datum transformations and their reversibility / Andrew Carey Ruffhead in Survey review, vol 50 n° 358 (January 2018)PermalinkConcept of AHRS algorithm designed for platform independent IMU attitude alignment / Dariusz Tomaszewski in Reports on geodesy and geoinformatics, vol 104 n° 1 (December 2017)PermalinkAppraisal of the Hellenic Geodetic Reference System 1987 based on backward-transformed ITRF coordinates using a national velocity model / M. Chatzinikos in Survey review, vol 49 n° 356 (November 2017)PermalinkWeighted coordinate transformation formulated by standard least-squares theory / D. Mihajlovic in Survey review, vol 49 n° 356 (November 2017)Permalink