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Zur Bestimmung des Erdschwerefeldes unter Verwendung des Maximum-Entropie-Prinzips / Rüdiger Lehmann (1994)
Titre : Zur Bestimmung des Erdschwerefeldes unter Verwendung des Maximum-Entropie-Prinzips Titre original : [Sur la détermination du champ de pesanteur terrestre en utilisant le principe d'entropie maximale] Type de document : Thèse/HDR Auteurs : Rüdiger Lehmann, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 1994 Collection : DGK - C Sous-collection : Dissertationen num. 425 Importance : 103 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-7696-9468-0 Note générale : Bibliographie Langues : Allemand (ger) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] Baltique, mer
[Termes IGN] champ de pesanteur local
[Termes IGN] distribution de Gauss
[Termes IGN] entropie
[Termes IGN] harmonique sphérique
[Termes IGN] levé gravimétrique
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] problème inverse
[Termes IGN] système non linéaireIndex. décimale : 30.40 Géodésie physique Résumé : (Auteur) The thesis deals with the problem of determining the outer gravity field of the Earth based on a finite number of data affected by measurement errors. It is described as a discrete inverse problem in an informational framework suggested by Tarantola and Valette (1982). Based on a conjunction operation for different states of information, a very general solution scheme for such problems is provided. For the first time we give a complete axiomatic foundation of this operation.
The mainstay of this work is the application of the solution scheme to the problem of modelling the disturbing potential in the outer space of the Earth. It is necessary to extend the scheme to account for unknown variance components, namely the squares of the unavoidable modellization errors. The result is not immediately a spatial potential function, but a state of information for the value of the disturbing potential at any point in the outer space, being the result of the conjunction of the states of information available. The solution scheme does not suggest a certain type of model for the representation of the potential, e.g. spherical harmonics could be used. Here the method of point masses in free (optimized) positions serves as an illustrating example.
For the definition of the probability distributions used we exclusively rely on the maximum entropy principle. This gives the least informative state of information consistent with given constraints. In this context the problem of constructing probability distributions for mass anomalies inside the Earth subject to spectral constraints for the outer gravity field is treated. The solution is presented for point mass anomalies and a number of practically occuring spectral constraints, both on a sphere as well as in a tangential plane.
In general, the probability distributions finally obtained for the representation of the state of information on the disturbing potential cannot be expressed analytically, because a multidimensional integral is not analytically tractable. However, two special cases exist, where an analytical solution is possible. Then we obtain either a t-distribution or a normal distribution for the disturbing potential value, both very well suited for estimation. In the remaining cases the resulting probability distributions can only be described by means of characteristic parameters. First of all, we investigate both the expectation as well as the mode (maximum likelihood point). Again, as the multidimensional integrals involved have no analytical solution, both can in general not be computed directly. Without numerical integration only the joint mode over the space of model parameters, modellization error squares, and the disturbing potential can be computed. This is accomplished by solving a nonlinear equation system.
If any, only the method of Monte Carlo integration is powerful enough to provide numerical approximates for the multidimensional integrals to be evaluated. The crucial point here is the proper choice of the pseudorandom distributions. For truely large dimension numbers even expensively determined pseudorandom distributions fall short. In a simple synthetic simulation study we compute marginal probability distributions for model parameters, for the modellization errors as well as for the disturbing potential by means of the Monte Carlo integration technique. In a larger scale simulation example, modelled close to the real behaviour of the gravity field in the Gulf of Bothnia, we try to assess biases of the maximum likelihood estimate. The Monte Carlo integration as well as the average second order remainder assessment do not agree well. Here the only conclusion to be drawn is: The biases do not form the largest constituent of the posterior errors in the results.
Finally we compute a local gravity field based on real data on the Gulf of Bothnia. We process more than 11000 gravimetric and more than 900 altimetric data. The results are two maximum likelihood solutions for up to 750 point masses in free positions. The first is based exclusively on the gravimetric data. The predicted geoid fits the altimetrically surveyed sea surface within 11 cm, that is not much more than the actual error of the altimetry. The second solution also includes the altimetry. Unlike the original method of point masses in free positions, we are now able to handle problems with different types of data, different data accuracies, as well as inhomogeneous spatial data coverage. This indicates the power of the suggested approach.Numéro de notice : 28063 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Thèse étrangère Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=63410 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 28063-01 30.40 Livre Centre de documentation Géodésie Disponible 28063-02 30.40 Livre Centre de documentation Géodésie Disponible Geodesy and geophysics / J. Kakkuri (1993)
Titre : Geodesy and geophysics : lectures notes for NKG autumn school 1992 organized by Nordiska kommissionen for geodesi, Korpilampi, Finland, 7-13 september 1992 Type de document : Monographie Auteurs : J. Kakkuri, Auteur Editeur : Helsinki : Finnish Geodetic Institute FGI Année de publication : 1993 Collection : Publications of the Finnish Geodetic Institute, ISSN 0085-6932 num. 115 Importance : 200 p. Format : 18 x 25 cm ISBN/ISSN/EAN : 978-951-711-155-3 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] Baltique, mer
[Termes IGN] Fennoscandie
[Termes IGN] géoïde
[Termes IGN] géophysique
[Termes IGN] niveau moyen des mers
[Termes IGN] océanographie
[Termes IGN] rebond post-glaciaire
[Termes IGN] variation séculaireIndex. décimale : 30.40 Géodésie physique Note de contenu : ANDERSEN, O.B. : Preface
EKMAN, M. : Postglacial rebound and sea level phenomena, with special refernce to Fennoscandia and Baltic Sea
KAKKURI, J. : The stress phenomenon in the Fennoscandian Shield
KNUDSEN, P. : Altimetry for geodesy and oceanography
TORGE, W. : Gravimetry and tectonics
VERMEER, M. : Terrain reduction and griding techniques for geoid determination
VERMEER, M. : Geoid determination using frequency domain techniques.Numéro de notice : 60928 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Recueil / ouvrage collectif Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=44218 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 60928-01 30.40 Livre Centre de documentation Géodésie Disponible 60928-02 67.02 Livre Centre de documentation Indéterminé Disponible Vertical movements of the Earth's crust in the baltic region / J. Randjarv (1993)
Titre : Vertical movements of the Earth's crust in the baltic region Type de document : Rapport Auteurs : J. Randjarv, Auteur Editeur : Helsinki : Finnish Geodetic Institute FGI Année de publication : 1993 Collection : Reports of the Finnish Geodetic Institute num. 93-2 Importance : 33 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-951-711-158-4 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géophysique interne
[Termes IGN] Baltique, mer
[Termes IGN] déformation verticale de la croute terrestre
[Termes IGN] réseau de nivellement
[Termes IGN] tectonique des plaquesRésumé : (Auteur) The map of the recent vertical crustal movements of the Baltic region was compiled on the basis of repeated precise levellings carried out in 1927 - 1973 and the rates of the vertical movement determined by Olgert Jakubovsky (1973) on the basis of tide gauges observations for the period from 1889 to 1970. The total length of the lines of relevellings is 6453 km, 4240 km of which have undergone a new levelling in the years 1967- 1973. Velocities of vertical movements of the Earth's crust in the nodal points of the levelling network are obtained with a 0.4 - 0.8 mm error per year. Numéro de notice : 61016 Affiliation des auteurs : non IGN Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=60866 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 61016-02 30.51 Livre Centre de documentation En réserve M-103 Disponible 61016-01 47.10 Livre Centre de documentation En réserve M-103 Disponible Oceanic upper mixed layer depth determination by the use of satellite data / Xin H. Yan in Remote sensing of environment, vol 32 n° 1 (01/04/1990)
[article]
Titre : Oceanic upper mixed layer depth determination by the use of satellite data Type de document : Article/Communication Auteurs : Xin H. Yan, Auteur ; J.R. Schubel, Auteur ; D.W. Pritchard, Auteur Année de publication : 1990 Article en page(s) : pp 55 - 74 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] bathymétrie
[Termes IGN] circulation océanique
[Termes IGN] image Nimbus-SMMR
[Termes IGN] océanographie spatiale
[Termes IGN] Sargasses, mer des
[Termes IGN] température de surface de la merNuméro de notice : A1990-082 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/0034-4257(90)90098-7 En ligne : https://doi.org/10.1016/0034-4257(90)90098-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=25500
in Remote sensing of environment > vol 32 n° 1 (01/04/1990) . - pp 55 - 74[article]Les aménagements du bassin d'Arcachon au 18ème siècle / Catherine Bousquet-Bressolier (1990)
Titre : Les aménagements du bassin d'Arcachon au 18ème siècle Type de document : Monographie Auteurs : Catherine Bousquet-Bressolier, Auteur ; F. Bouscau, Auteur ; M.J. Pajot, Auteur Editeur : Dinard : Laboratoire de géomorphologie de l'EPHE Année de publication : 1990 Collection : Mémoires du laboratoire de géomorphologie de l'EPHE, ISSN 0750-6066 num. 43 Importance : 224 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-2-900111-19-2 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Géographie régionale France
[Termes IGN] agriculture
[Termes IGN] aménagement
[Termes IGN] Arcachon
[Termes IGN] Arcachon (bassin d')
[Termes IGN] dix-huitième siècle
[Termes IGN] dune
[Termes IGN] géologie locale
[Termes IGN] géomorphologie locale
[Termes IGN] marais salant
[Termes IGN] populationNuméro de notice : 59809 Affiliation des auteurs : non IGN Nature : Monographie Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=60632 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 59809-01 63.72 Livre Centre de documentation En réserve M-103 Disponible Evaluation de l'usage du sol dans le secteur du bassin d'Arcachon par télédétection / Institut d'aménagement et d'urbanisme de la région Ile-de-France (1990)PermalinkPhotogrammétrie en zone littorale / A. Fourgassie in Bulletin [Société Française de Photogrammétrie et Télédétection], n° 117 (Janvier 1990)PermalinkRezente vertikale Erdkrustenbewegungen im südlichen ostseeraum / A. Weise (1990)PermalinkZur Energie der Chandler Polschwankung / H. Lenhardt (1990)PermalinkAn algorithm for snow and ice detection using AVHRR data : an extension to the Apollo software package / G. Gesell in International Journal of Remote Sensing IJRS, vol 10 n°4-5 (May 1989)PermalinkComparison between satellite and ship measurements of sea surface temperature in the north-east Atlantic Ocean / I.S. Robinson in International Journal of Remote Sensing IJRS, vol 10 n°4-5 (May 1989)PermalinkMesoscale variability of sea surface temperature in the north Atlantic / T. Viehoff in International Journal of Remote Sensing IJRS, vol 10 n°4-5 (May 1989)PermalinkRemote observation of sea surface and atmosphere : the oceanic skin effect / C.L. Hepplewhite in International Journal of Remote Sensing IJRS, vol 10 n°4-5 (May 1989)PermalinkAnalysis of Thematic Mapper data for studying the suspended matter distribution in the coastal area of the German bight (North sea) / R. Doerffer in Remote sensing of environment, vol 28 n° 1 (April - June 1989)PermalinkRemote sensing and numerical modeling of suspended sediment in Laguna de terminos, Campeche, Mexico / J.R. Jensen in Remote sensing of environment, vol 28 n° 1 (April - June 1989)Permalink