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Unifying regularization and Bayesian estimation methods for enhanced imaging with remotely sensed data - part 2: implementation and performance issues / Y.V. Shkvarko in IEEE Transactions on geoscience and remote sensing, vol 42 n° 5 (May 2004)
[article]
Titre : Unifying regularization and Bayesian estimation methods for enhanced imaging with remotely sensed data - part 2: implementation and performance issues Type de document : Article/Communication Auteurs : Y.V. Shkvarko, Auteur Année de publication : 2004 Article en page(s) : pp 932 - 940 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image
[Termes IGN] entropie
[Termes IGN] équation non linéaire
[Termes IGN] estimation bayesienne
[Termes IGN] image ERS-SAR
[Termes IGN] implémentation (informatique)
[Termes IGN] inversion
[Termes IGN] méthode robusteRésumé : (Auteur) The fused Bayesian-regularization (FBR) method from a companion paper provides a rigorous theoretical formalism for optimal estimation of the power spatial spectrum pattern (SSP) of the wave field scattered from the probing surface as it is required for enhanced radar imaging of the remotely sensed scenes. Being nonlinear and solution-dependent, the optimal FBR method requires extremely complex nonlinear solution-dependent operator inversions and, therefore, cannot be recommended as a numerically realizable estimator of the SSP. Here, we design a family of robust easy-to-implement FBR algorithms, provide the relevant computational recipes, and discuss their performances. We comment on the practical aspects of the robustified FBR estimators, such as numerical implementation and improvement in the output SNR. The advantage in using the proposed robust FBR method is demonstrated through simulations of enhancing the SAR images formed using the conventional matched filtering of the trajectory signal. Numéro de notice : A2004-194 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2003.823279 En ligne : https://doi.org/10.1109/TGRS.2003.823279 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26721
in IEEE Transactions on geoscience and remote sensing > vol 42 n° 5 (May 2004) . - pp 932 - 940[article]Voir aussiRéservation
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Code-barres Cote Support Localisation Section Disponibilité 065-04051 RAB Revue Centre de documentation En réserve L003 Disponible Modeling reality: how computers mirror life / Iwo Bialynicki-Birula (2004)
Titre : Modeling reality: how computers mirror life Type de document : Guide/Manuel Auteurs : Iwo Bialynicki-Birula, Auteur ; Iwona Bialynicka-Birula, Auteur Editeur : Oxford, Londres, ... : Oxford University Press Année de publication : 2004 Importance : 180 p. Format : 16 x 24 cm + cédérom ISBN/ISSN/EAN : 978-0-19-853100-5 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Intelligence artificielle
[Termes IGN] algorithme génétique
[Termes IGN] automate cellulaire
[Termes IGN] entropie
[Termes IGN] intelligence artificielle
[Termes IGN] modèle mathématique
[Termes IGN] objet fractal
[Termes IGN] probabilités
[Termes IGN] réalité virtuelle
[Termes IGN] réseau neuronal artificiel
[Termes IGN] théorie des graphes
[Termes IGN] théorie des jeuxRésumé : (Auteur) This book originated from a series of lectures delivered by the first author at the Warsaw School of Social Psychology and at Warsaw University over the last six years. The purpose of these lectures was to give a very broad overview of various aspects of modeling for a mixed audience, from students of mathematics, computer science, and physics to students of biology and social sciences. Considering the different levels of mathematical literacy among those who attended the lectures, we have relied only on the mathematical concepts known to high school graduates. Therefore, our book can be understood by a wide spectrum of readers - from ambitious high school students to graduate students of all specialities. We were trying to keep the mathematics at the high school level; however, some chapters may require an additional effort since they describe modern advances in computer modeling. Note de contenu : I. From building blocks to computers : Models and modeling
2. The game of life : A legendary cellular automaton
3. Heads or tails : Probability of an event
4. Galton's board : Probability and statistics
5. Twenty questions : Probability and information
6. Snowflakes : The evolution of dynamical systems
7. The Lorenz butterfly : Deterministic chaos
8. From Cantor to Mandelbrot : Selfsimilarity and fractals
9. Typing monkeys : Statistical linguistics
10. The bridges of Königsberg : Graph theory
11. Prisoner's dilemma : Game theory
12. Let the best man win : Genetic algorithms
13. Computers can learn : Neural networks
14. Unpredictable individuals : Modeling society
15. Universal computer : The Turing machine
16. Hal, R2D2, and Number 5 : Artificial intelligenceNuméro de notice : 16440 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Manuel de cours Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=55163 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 16440-01A 26.40 Manuel Informatique Centre de documentation Informatique Disponible Perte d'information lors de l'agrégation spatiale en hydrologie : application à un modèle hydrologique / F. Laurent in Revue internationale de géomatique, vol 8 n°1-2 (mars – août 1998)
[article]
Titre : Perte d'information lors de l'agrégation spatiale en hydrologie : application à un modèle hydrologique Type de document : Article/Communication Auteurs : F. Laurent, Auteur ; F. Delclaux, Auteur ; D. Graillot, Auteur Année de publication : 1998 Article en page(s) : pp 99 - 119 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] agrégation spatiale
[Termes IGN] base de données localisées
[Termes IGN] entropie
[Termes IGN] hydrologie
[Termes IGN] limite de résolution géométrique
[Termes IGN] modèle numérique de terrainNuméro de notice : A1998-163 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=26130
in Revue internationale de géomatique > vol 8 n°1-2 (mars – août 1998) . - pp 99 - 119[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 047-98011 RAB Revue Centre de documentation En réserve L003 Disponible 047-98012 RAB Revue Centre de documentation En réserve L003 Disponible Stochastisch-geometrische Beschreibung, Filterung und Präsentation des Reliefs / Andrzej Borkowski (1994)
Titre : Stochastisch-geometrische Beschreibung, Filterung und Präsentation des Reliefs Titre original : [Description géométrique aléatoire, filtrage et présentation du relief] Type de document : Thèse/HDR Auteurs : Andrzej Borkowski, Auteur Editeur : Munich : Bayerische Akademie der Wissenschaften Année de publication : 1994 Collection : DGK - C Sous-collection : Dissertationen num. 431 Importance : 85 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 3-7696-9474-4 Note générale : Bibliographie Langues : Allemand (ger) Descripteur : [Vedettes matières IGN] Photogrammétrie numérique
[Termes IGN] discrétisation
[Termes IGN] entropie
[Termes IGN] filtrage linéaire
[Termes IGN] modèle numérique de terrain
[Termes IGN] représentation discrèteIndex. décimale : 33.30 Photogrammétrie numérique Résumé : (Auteur) This Doctoral thesis covers two main items: the linear relief filtering with restrictions and the discretization of relief without information loss. The modelling of the relief, which is assumed to be a realization of a two-dimensional normal, homogeneous, and bandlimited stochastic process, is based on the theory of stochastic processes. The adequacy of the model choice and its assumptions has been verified using some natural reliefs of the Earth's surface.
Concerning linear filtering the following quantity and quality restrictions were used: preservation of relief shape, of volume, of terrain inclination and finally, the reduction of relative extremums according to Toepfer's choice rule are expressed in stochastic process terminology. The above conditions are realized by the two-dimensional, non-recursive, digital linear filtering (e.g. for generalization purposes, for relief smoothing using digital data). In order to estimate the required parameters the complete knowledge of second order process quantities (autocovariance function or spectral density) is necessary. Numerical experiments with different relief types stored in digital terrain models (DTM) confirmed the possibility of practical realization of linear filtering with restrictions.
The conventional sampling theorem concerning bandlimited random signals is based on the discretization of the abscissa. In opposite to that, the contour line representation of the relief corresponds to a discretization on the ordinate. Sampling rules according to the ordinate, consistent with the original sampling theorem, are given for both one-dimensional and two-dimensional continuous stochastic processes and additionally for discrete signals (time series). Vertical and horizontal intervals of discretization relate to each other by the correlation coefficients of neighboured signal values for discrete signals or by the second order moment of terrain inclination for continuous processes. An estimation approach for optimum grid cell size of DTM interpolated from topographic maps is proposed. This grid ensures a complete as well as a non-redundant data capture from contour line information. The approach is based on the relation between vertical and horizontal intervals of discretization. The necessary parameter i.e. the variance of terrain inclination is estimated using measured lengths of contour lines at different height levels. The consistence of the discretization rules has been confirmed by numerical experiments.Numéro de notice : 28057 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse étrangère Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=63404 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 28057-01 33.30 Livre Centre de documentation Photogrammétrie - Lasergrammétrie Disponible 28057-02 33.30 Livre Centre de documentation Photogrammétrie - Lasergrammétrie Disponible 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 Estimation and spectral analysis / J.A.R. Blais (1988)PermalinkEntropy and distance of random graphs with application to structural pattern recognition / A. Wong in IEEE Transactions on Pattern Analysis and Machine Intelligence, PAMI, vol 7 n° 5 ([01/09/1985])PermalinkGeneralization, a means to transmit reliable messages through unreliable channels / Rudolf Knöpfli in Annuaire international de cartographie, n° 22 (1982)PermalinkThermodynamique et électrostatique / J.P. Maury (1970)PermalinkChaleur, thermodynamique, états de la matière / Pierre Fleury (1968)PermalinkThermodynamique / Georges Bruhat (1968)PermalinkMécanique statistique classique / Emile Borel (1927)Permalink