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Taylor expansion of GPS observations equations / X. Jin (1995)
Titre : Taylor expansion of GPS observations equations Type de document : Monographie Auteurs : X. Jin, Auteur Editeur : Delft [Pays-Bas] : Delft University of Technology Année de publication : 1995 Collection : LGR-SERIES num. 11 Importance : 48 p. Format : 21 x 30 cm Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] équation linéaire
[Termes IGN] erreur systématique
[Termes IGN] matrice de covariance
[Termes IGN] phase GPS
[Termes IGN] série de Taylor
[Termes IGN] signal GPS
[Termes IGN] stabilité
[Termes IGN] système de référence céleste
[Termes IGN] temps de propagation
[Termes IGN] temps réelIndex. décimale : 30.60 Géodésie spatiale Résumé : (Auteur) In addition to giving an alternative derivation of GPS carrier observation equations, this research aims mainly at deriving the Taylor expansion of GPS observation equations.
The derivation of GPS carrier observation equations can be found in many literatures. The main difference between the alternative derivation of carrier observation equations and many others is that no assumptions in the former are made on the stability of the satellite clock. In addition. the alternative derivation can show clearly what the carrier observable ambiguity consists of, so that one can understand exactly what is cancelled in single, double or triple differences of carrier observations.
In order to solve GPS observation equations, one needs to know the transmission time of the GPS signal which is usually determined by using iterations or code observations. Since using iterations is rather time consuming, one should try to avoid this approach, especially in real time GPS applications. This research shows by a real data set that as large as one millisecond gross error can be included in a code observation. Therefore using code observations to determine the travel time of the GPS signal will possibly lead to seriously biased results. In addition, the use of code observations leads to that the coefficients of linearized GPS observation equations are functions of code observations, which makes it difficult to correctly compute the covariance matrix of the estimates of unknowns.
This research proves that GPS observation equations can be expanded in Taylor series which contains only up to first-order derivative quantities. Since the expansion does not contain the travel time of the GPS signal, solving it requires neither iterations nor code observations for the determination of the transmission time of the GPS signal. The use of the Taylor expansion of GPS observation equations can, therefore, save computing time and avoid the impacts of any gross errors in code observations on computed observations. Thus the expansion is particularly useful for real time high precision GPS applications. Additionally, the Taylor expansion of GPS observation equations makes it possible to show explicitly the exact coefficients of linearized GPS observation equations.Numéro de notice : 18212 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=55352 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 18212-01 30.60 Livre Centre de documentation Géodésie Disponible Zur analytischen Bahnberechnung künstlicher Erdsatelliten mittels konformer Transformationen / R. You (1995)
Titre : Zur analytischen Bahnberechnung künstlicher Erdsatelliten mittels konformer Transformationen Titre original : [Sur le calcul analytique d'orbite de satellites artificiels terrestres au moyen de transformations conformes] Type de document : Thèse/HDR Auteurs : R. You, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 1995 Collection : DGK - C Sous-collection : Dissertationen num. 440 Importance : 213 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-9483-3 Note générale : Bibliographie Langues : Allemand (ger) Descripteur : [Vedettes matières IGN] Techniques orbitales
[Termes IGN] équation linéaire
[Termes IGN] ERS-1
[Termes IGN] Lageos
[Termes IGN] mécanique orbitale
[Termes IGN] mouvement Képlerien
[Termes IGN] orbite
[Termes IGN] orbitographie
[Termes IGN] satellite GPS
[Termes IGN] transformation canoniqueRésumé : (Auteur) In this dissertation, the motions of satellites affected by conservative and nonconservative forces in the Newtonian mechanics are interpreted as geodesic motions. The dynamical geometrical properties of the motions are analyzed. In particular, the motions of satellites in the Newtonian Earth's gravitational field are explained as the minimal geodesic flows on Maupertuis' manifolds according to the Maupertuis' variational principle of least action. The Euclidean space, in which satellites move, is a conformal map of a Maupertuis' manifold. The Maupertuis' manifolds are in detail discussed. Their embedding is solved according to the Brinkmann's embedding theorem and illustrated for the elliptic Kepler motions and orbits perturbed by the Earth's oblateness.
To solve analytically the problems of satellite motions, the conformal Mapping of type KS transformation is introduced. In particular, a set of canonical KS elements for elliptic Kepler motions is derived. By virtue of this conformal transformation, the equations of the Kepler motion are regularized und transformed into linear differential equations. At the same time, the equations of the elliptic Kepler motion are also stabilized. These canonical KS elements are free from all singularities which occur in the classical Kepler elements. Especially, the solutions of the perturbation computation with the KS elements keep away from the strictly resonancelike amplification. An analytical solution of first order due to perturbations of an anisotropic terrestial gravitational field, the direct lunisolar influence, the tides of the earth, the relativistic gravitational effects, the atmospheric drag and the direct solar radiation pressure is given and compared with a numerical integration on the orbits of GPS, ERS1 and LAGEOS1.Numéro de notice : 28049 Affiliation des auteurs : non IGN Thématique : IMAGERIE/POSITIONNEMENT Nature : Thèse étrangère Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=63396 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 28049-01 21.10 Livre Centre de documentation Technologies spatiales Disponible 28049-02 21.10 Livre Centre de documentation Technologies spatiales Disponible Aufbau qualitativ hochwertiger Geländemodelle aus Höhenlinien / G. Aumann (1994)
Titre : Aufbau qualitativ hochwertiger Geländemodelle aus Höhenlinien Titre original : [Création d'un modèle numérique de terrain de grande qualité à partir de courbes de niveau] Type de document : Thèse/HDR Auteurs : G. Aumann, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 1994 Collection : DGK - C Sous-collection : Dissertationen num. 411 Importance : 97 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-9456-7 Note générale : Bibliographie Langues : Allemand (ger) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] discrétisation
[Termes IGN] extraction automatique
[Termes IGN] extraction de traits caractéristiques
[Termes IGN] interpolation
[Termes IGN] méthode des éléments finis
[Termes IGN] squelettisation
[Termes IGN] Triangulated Irregular NetworkIndex. décimale : 33.30 Photogrammétrie numérique Résumé : (Auteur) The present interest on countrywide high quality digital terrain models (DTM) was the reason for this thesis where possible strategies for the generation of high quality digital terrain models from contours are shown. The paper deals of two main subjects, the preparation of original data and the following generation of DTM.
The basic requirement for the generation of a high quality DTM is the preparation of good original data. Digitized contours only contain the geometrical information about the terrain, which is only one pan of the information received from contours. The geomorphological information, which is very important for the generation of a DTM is only given implicitly by digitized contours. In this paper a method was evaluated and tested, which utilizes the implicit geomorphological information of contours automatically. In practical examples it was demonstrated that this new procedure utilizes automatically the geomorphological information of contours, which is necessary for the generation of a high quality DTM. The skeleton lines automatically found by this procedure agree very well to those evaluated graphically.
The investigations on DTM generation from contours confirm the statement that it is very important for the DTM generation to include geomorphological information, too. Since digital terrain models structured by gridded networks have a fundamentally more simple data organization than digital terrain models structured by triangulated networks, they are prefered for the DTM generation for big areas. A triangulation of the original data cannot be avoided. The triangulation is needed to detect the skeleton lines and for the generation of the DTM. But this triangulation can be done stepwise in smaller parts. The generation of a filtered grid structured DTM by the method of finite elements is preferable for generating high quality digital terrain models for large areas. By this method for the DTM generation contours and skeleton lines are used as well as artificial reference points in areas without reference data.Numéro de notice : 28073 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse étrangère Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=63420 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 28073-01 33.30 Livre Centre de documentation Photogrammétrie - Lasergrammétrie Disponible 28073-02 33.30 Livre Centre de documentation Photogrammétrie - Lasergrammétrie Disponible Ausgleichungsrechnung in nichtlinearen Modellen / P. Lohse (1994)
Titre : Ausgleichungsrechnung in nichtlinearen Modellen Titre original : [Calcul de compensation dans les modèles non linéaires] Type de document : Thèse/HDR Auteurs : P. Lohse, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 1994 Collection : DGK - C Sous-collection : Dissertationen num. 429 Importance : 131 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 3-7696-9472-7 Note générale : Bibliographie Langues : Allemand (ger) Descripteur : [Vedettes matières IGN] Analyse numérique
[Termes IGN] modèle de Gauss-Markov
[Termes IGN] modèle non linéaire
[Termes IGN] programmation non linéaireRésumé : (Auteur) Within the framework of this thesis adjustment is investigated according to the least squares method in a nonlinear Gauss-Markoff model. The minimization of the least squares criterion regularly results in a solution of an optimization problem. The necessary condition for a local minimum (optimality of the first order) leads to the system of nonlinear normal equations. The sufficient condition for a local minimum (optimality of the second order) provides information about the admissibility of the least squares method. By means of the geometrical analysis of the minimum problem it is possible to successfully present a clear interpretation of the optimality criteria.
Methods for the determination of the total solution set of a nonlinear algebraic system of normal equations are elucidated. Subsequently there follows the geometrical discussion of the Gaufi-Newton Method as well as the Newton-Raphson Method, two methods of different order of differentiation for the iterative refinement of an initial approximation value.
Using the example of the resection problem (with distances) the results of the theoretical conside--rations are confirmed. Special emphasis is thereby placed on the determination of the total solution set of the system of normal equations as well as on the admissible solutions of the minimum pro-blem. Two methods are put forward for the computation of suitable initial values in the case of the iterative solution of the system of normal equations.
The final part of the work consists of a discussion regarding the geodetic resection and intersection problems with respect to the model choice and to the nonlinear normal equations.Numéro de notice : 28059 Affiliation des auteurs : non IGN Thématique : MATHEMATIQUE Nature : Thèse étrangère Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=63406 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 28059-01 23.40 Livre Centre de documentation Mathématiques Disponible 28059-02 23.40 Livre Centre de documentation Mathématiques Disponible Contouring, a guide to the analysis and display of spatial data / David F. Watson (1994)
Titre : Contouring, a guide to the analysis and display of spatial data Type de document : Monographie Auteurs : David F. Watson, Auteur Editeur : Oxford [Royaume-Uni] : Pergamon Press Année de publication : 1994 Autre Editeur : Amsterdam [Pays Bas] : Elsevier Collection : Computer methods in the geosciences num. 1 Importance : 321 p. Format : 15 x 24 cm + 1 disquette ISBN/ISSN/EAN : 978-0-08-040286-4 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] base de données topographiques
[Termes IGN] Basic
[Termes IGN] coordonnées horizontales
[Termes IGN] données localisées
[Termes IGN] gradient
[Termes IGN] interpolation spatiale
[Termes IGN] visualisation de donnéesIndex. décimale : 37.00 Géomatique - information géographique - infrastructure de données Numéro de notice : 62724 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Monographie DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=61115 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 62724-01 37.00 Livre Centre de documentation Géomatique Disponible Ein Modell für die hochgenaue Navigation autonomer flächenbeweglicher Fahrzeuge / J. Kusche (1994)PermalinkEstimation, modélisation et langage de déclaration et de manipulation de champs spatiaux continus / Dillon Pariente (1994)PermalinkEstimation of sea dynamic topography, ocean tides, and secular changes from Topex altimeter data / Y.M. Wang (1994)PermalinkGénération d'un MNT en milieu urbain à partir d'un couple de photographies aériennes / Tsitohaina Andrianjafiravelo (1994)PermalinkGeodätische Analyse inhomogener Deformationen mit nichtlinearen Transformationsfunktionen / J. Reinking (1994)PermalinkGeodätische Hauptaufgaben auf Flächen in kartesischen Koordinaten / K. Aringer (1994)PermalinkPermalinkIntroduction à la relativité générale / Jean-Claude Radix (1994)PermalinkIntroduction to the use of Geographic Information Systems for practical hydrology / A. Meijerink (1994)PermalinkMathématiques, enseignement de spécialité terminale TS programme 1994 / G. Bontemps (1994)Permalink