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Titre : Geoidbestimmung mit geopotentiellen Koten Titre original : [La détermination du géoïde avec des cotes géopotentielles] Type de document : Thèse/HDR Auteurs : M. Feistritzer, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 1998 Collection : DGK - C Sous-collection : Dissertationen num. 486 Importance : 90 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-9526-7 Note générale : Bibliographie Langues : Allemand (ger) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] cote géopotentielle
[Termes IGN] ellipsoïde (géodésie)
[Termes IGN] géoïde terrestre
[Termes IGN] isostasie
[Termes IGN] potentiel de pesanteur terrestre
[Termes IGN] problème de DirichletIndex. décimale : 30.41 Géoïde Résumé : (Auteur) Starting from geopotential numbers as data a new method of downward continuation of the disturbing potential into the interior of the earth onto an approximating surface of the geoid is introduced. In contrast to many other methods an ellipsoid of revolution is used as a reference surface instead of a sphere and furthermore the potential itself is continued downward and not derivatives of the potential (gravity anomalies, deflections of the vertical, gradiometry data). The influence of the topographic masses and their isostatic compensation is taken into account with a remove-restore technique where the kernel of the Newton-Integral is expanded into converging spherical harmonics series. The downward continuation is then performed by a generalized Tikhonov regularisation method which obtains minimal errors and it must be added that both random as well as often omitted systematic parts are considered. The downward continued disturbing potential is then used for geoid determination by using Bruns formula. To check theory test calculations have been performed for the area of Baden-Wiirttemberg. Numéro de notice : 67049 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=61691 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 67049-01 30.41 Livre Centre de documentation Géodésie Disponible 67049-02 30.41 Livre Centre de documentation Géodésie Disponible Mehrdimensionale Interpolation von Meteorologischen Feldern zur Berechnung der Brechungsbedingungen in der Geodäsie / Hans Arnold Hirter (1998)
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Titre : Mehrdimensionale Interpolation von Meteorologischen Feldern zur Berechnung der Brechungsbedingungen in der Geodäsie Titre original : [Interpolation multidimensionnelle de campagnes météorologiques pour le calcul des modalités de la réfraction en géodésie] Type de document : Thèse/HDR Auteurs : Hans Arnold Hirter, Auteur Editeur : Zurich : Institut für Geodäsie und Photogrammetrie IGP - ETH Année de publication : 1998 Collection : IGP Mitteilungen, ISSN 0252-9335 num. 064 Importance : 116 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-906467-11-5 Note générale : Bibliographie Langues : Allemand (ger) Descripteur : [Vedettes matières IGN] Rayonnement électromagnétique
[Termes IGN] collocation
[Termes IGN] correction troposphérique
[Termes IGN] covariance
[Termes IGN] interpolation
[Termes IGN] propagation troposphérique
[Termes IGN] réfraction
[Termes IGN] réfraction atmosphérique
[Termes IGN] signal GPSIndex. décimale : 24.30 Rayonnement électromagnétique Résumé : (Auteur) The refractive effects in geodetic applications are known as unpleasant sources of errors. Microwave sources, as being used with Global Positioning System (GPS) are subjected to the physical laws of refraction when traversing the atmosphere. There are two methods to reduce the tropospheric error: The first is modeling the atmospheric effects and the second is to estimate the tropospheric parameters. Here we focus our attention on modeling of the troposphere.
The magnitude of the effects depends upon the index of refraction and its spatial distribution as well as its temporal fluctuation. The index of refraction depends upon the frequency of the electromagnetic measuring beam and the actual state of the troposphere being relevant to refraction. The index of refraction can be described by the meteorological magnitudes such as pressure, temperature and humidity. If the refractive relationships are known respectively the values of the pressure, temperature and humidity alongside the entire beam the Path Delay can be determined for the latter. For calculating the Path Delay at an arbitrary location and arbitrary time the discrete meteorological data being sampled has to be inter- respectively extrapolated. Precisely this fact is being taken into account by the method of Krigings or Collocation. On the basis of arbitrarily distributed samples acquired in space and time, the collocation permits to execute a 4-dimensional modeling by taking into account simple approximated physical models. The deviation from this approximation is explained by the functional model with two stochastic segments (signal and noise). The physical model is adapted optimally to the measured values by the collocation.
The zenith Path Delays (in the order of 2 m) calculated with the model can be inserted directly into the evaluation software of the GPS. As opposed to the standard models, the GPS-evaluation with Path Delays yields more consistent solutions which imply that the variance of the GPS solution is being reduced. Using the modeled Path Delays in the local Turtmann GPS testing-network with large height-differences, the repeatability of the height measurements is significantly increased (up to a factor of 2).Numéro de notice : 67046 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse étrangère DOI : 10.3929/ethz-a-001591486 En ligne : http://dx.doi.org/10.3929/ethz-a-001591486 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=61689 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 67046-01 24.30 Livre Centre de documentation Physique Disponible 67046-02 24.30 Livre Centre de documentation Physique Disponible
Titre : Modex : signaux et systèmes, [réimpression de 2007] Type de document : Guide/Manuel Auteurs : Stéphane Mallat, Auteur Editeur : Palaiseau : Ecole Polytechnique EP Année de publication : 1998 Importance : 137 p. Format : 21 x 30 cm Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Traitement du signal
[Termes IGN] compression d'image
[Termes IGN] compression de données
[Termes IGN] convolution (signal)
[Termes IGN] filtrage linéaire
[Termes IGN] filtre passe-bande
[Termes IGN] filtre passe-bas
[Termes IGN] modèle par fonctions rationnelles
[Termes IGN] quantité discrète
[Termes IGN] repliement de spectre
[Termes IGN] série de Fourier
[Termes IGN] signal aléatoire
[Termes IGN] signal analogique
[Termes IGN] traitement d'image
[Termes IGN] traitement du signal
[Termes IGN] transformation de Fourier
[Termes IGN] transformation de Laplace
[Termes IGN] transformation en ZIndex. décimale : 24.20 Traitement du signal Numéro de notice : 13957 Affiliation des auteurs : non IGN Thématique : IMAGERIE/POSITIONNEMENT Nature : Manuel de cours Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=46363 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 13957-01 24.20 Livre Centre de documentation Physique Disponible 13957-02 24.20 Livre Centre de documentation Physique Disponible
Titre : On the Unification of Indonesian Local Height Systems Type de document : Thèse/HDR Auteurs : Khafid, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 1998 Collection : DGK - C Sous-collection : Dissertationen num. 488 Importance : 110 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-9528-1 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes de référence et réseaux
[Termes IGN] archipel
[Termes IGN] données altimétriques
[Termes IGN] données GPS
[Termes IGN] données ITGB
[Termes IGN] Earth Gravity Model 1996
[Termes IGN] harmonique sphérique
[Termes IGN] Indonésie
[Termes IGN] Java (île de)
[Termes IGN] niveau moyen des mers
[Termes IGN] problème des valeurs limites
[Termes IGN] réseau altimétrique local
[Termes IGN] Sumatra
[Termes IGN] système de référence altimétriqueIndex. décimale : 30.10 Systèmes de référence et réseaux géodésiques Résumé : (Auteur) Height systems are usually referred to the mean sea level at tide gauges. Due to the deviation of mean sea level from one equipotential surface of the Earth's gravity field, the geoid, off-sets exist between the various height systems. These off-sets also affect derived quantities such as gravity anomalies. As long as the direct determination of the potential difference between two datum points, by geodetic levelling and gravimetry , is possible the connection, i.e. unification, of height systems is straightforward. It is a serious problem, however, whenever height datum zones are disconnected by sea. With the advent of advanced space positioning techniques and satellite altimetry new solution strategies for the worldwide unification of height systems came into discussion. This investigation deals with the regional unification of height systems for the area of the Indonesian archipelago.
It is a well-known fact that height datum unification is a global problem. However under certain circumstances it is possible to restrict the unification to a certain part of the Earth. Solution strategies make use of a land, a sea and an integrated component. The sea approach is based on satellite altimetry and oceanic levelling, the land approach on space positioning and spirit levelling, including tide gauge registrations. The link between both components is the solution of the geodetic boundary value problem applied regionally, with the aim to provide potential differences between the various vertical datum systems.
The five fundamental elements related to unification of height systems are investigated individually. Mean sea surface heights are determined by satellite radar altimetry, precise orbit ephemerides and corrections for tides and mesoscale ocean variations. By applying collinear pass analysis, crossover adjustment and a least-squares fit to the TOPEX/POSEIDON (T/P) mean sea surface, the mean sea surface in Indonesian waters is determined using the combined altimetry data from the missions Geosat/ERM, ERS-1/35 days, and T/P with an estimated accuracy of 10 cm. The high resolution data set of the ERS-1/168 days repeat mission has been processed with a simplified procedure. The result is consistent with that of the combination solution. As second element sea surface topography is derived from ocean levelling employing hydrographic data. The sea surface topography for Indonesian waters, especially in the eastern Indonesian region, is computed using several oceanographic data sets, the spherical harmonic model of the old Levitus data set up to degree and order 36, data from the Snellius-I and II expeditions, and the recent data set of the World Ocean Atlas 1994. The accuracy of ocean levelling depends on the measurement errors, data sampling and the reference surface. The assumption of a level of no motion at a certain depth, in this investigation 2000 dB is required to eliminate a fundamental indeterminancy. It is a problematic assumption. Further improvement will be possible once better data coverage and higher accuracy measurements are available. To increase the accuracy of local height datum connection, as third element the relative geoid computation is investigated. The relative geoid computation with inclusion of the height off-sets as unknowns should be the appropriate strategy for the solution of height datum connection over small distances between computation points. Finally as fourth and fifth element, the levelling network and the possibility of geodetic space techniques (GPS and VLBI) for height datum connection in Indonesia are reviewed. The levelling networks of Sumatra, Java, Kalimantan, Bali, Lombok, Sulawesi East Timor, Maluku, Seram have been extended by BAKOSURTANAL in recent years. A geodynamic GPS network is under development in the context of the GEODYSSEA project. They offer a promising prospect for use in a precise regional vertical datum connection. From the comparison of sea surface topography as derived from steric levelling and from altimetry and a spherical harmonic geoid model (EGM96) up to degree and order 360, it can be concluded that sea surface topography as computed from the World Ocean Atlas 1994 can be used for preliminary Indonesian height datum connections. The sea surface topography in the South-West coast of Sumatra is about -16 cm, in the South coast of Java it increases from -14 cm (west) to -8 cm (east).Numéro de notice : 28005 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=63352 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 28005-01 30.10 Livre Centre de documentation Géodésie Disponible 28005-02 30.10 Livre Centre de documentation Géodésie Disponible
Titre : Photogrammétrie analytique : traitement des perspectives centrales Type de document : Guide/Manuel Auteurs : Philippe Hottier , Auteur
Editeur : Champs-sur-Marne : Ecole nationale des sciences géographiques ENSG Année de publication : 1998 Importance : 80 p. Format : 21 x 30 cm Langues : Français (fre) Descripteur : [Vedettes matières IGN] Photogrammétrie analytique
[Termes IGN] angle de visée
[Termes IGN] matrice
[Termes IGN] perspectiveIndex. décimale : 33.20 Photogrammétrie analytique Numéro de notice : 13285 Affiliation des auteurs : IGN (1940-2011) Thématique : IMAGERIE Nature : Manuel de cours IGN Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=46276 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 13285-01 33.20 Livre Centre de documentation En réserve M-103 Disponible PermalinkPermalinkPermalinkReconstruction automatique des courbes de niveau à partir de cartes scannées en couleurs / François Dupont (1998)
PermalinkVerwendung und Bewertung von a-priori Information bei potentiell singulären Inversionsproblemen am Beispiel der gravimetrischen Bestimmung von Dichteverteilungen / P.L. Smilde (1998)
PermalinkPermalinkDiscrete visibility problems and graph algorithms / E. Puppo in International journal of geographical information science IJGIS, vol 11 n° 2 (February 1997)
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