Tesis sobre el tema "Données spectrales et spatiales"
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Erudel, Thierry. "Caractérisation de la biodiversité végétale en milieu montagnard et de piedmont par télédétection : apport des données aéroportées à très hautes résolutions spatiales et spectrales". Thesis, Toulouse, ISAE, 2018. http://www.theses.fr/2018ESAE0018/document.
This thesis highlighted the interest of using data with very high spatial and spectral resolution for the characterization of plant biodiversity in mountain areas. On the one hand, it has been shown that (in situ or airborne) hyperspectral data can discriminate plant habitats in a mountain peatbog. The difficulty of this study comes from the strong heterogeneity that exists within a bog that has strong floristic gradients and the definition of habitat classes that group several plant species (sometimes common from one class to another). More specifically, this thesis made it possible to highlight that discrimination could be carried out according to three approaches starting from measures of similarity applied to the spectral signature by applying a supervised classification which takes into account local information (spectral indices of vegetation) or global information (different spectral domains). The best results to distinguish these different habitat classes are not obtained with the spectral signature but with transformed spectral signatures (CRDR) in the spectral range[350-1350 nm]. The spectral vegetation indices that have been selected from a non-exhaustive base, which characterizes other plant species, are also mainly located in this spectral range. Moreover, this thesis highlighted the interest of applying a classifier little used for classification but rather for dimension reduction (RLR). Fine mapping of habitats was also carried out using airborne hyperspectral data
Chane, Camille. "Intégration de systèmes d'acquisition de données spatiales et spectrales haute résolution, dans le cadre de la génération d'informations appliquées à la conservation du patrimoine". Phd thesis, Université de Bourgogne, 2013. http://tel.archives-ouvertes.fr/tel-00909743.
Simon, Chane Camille. "Intégration de systèmes d'acquisition de données spatiales et spectrales haute résolution, dans le cadre de la génération d'informations appliquées à la conservation du patrimoine". Thesis, Dijon, 2013. http://www.theses.fr/2013DIJOS008/document.
The concern and interest of this PhD thesis is the registration of featureless 3D and multispectral datasets describing cultural heritage objects.In this context, there are few natural salient features between the complementary datasets, and the use of targets is generally proscribed.We thus develop a technique based on the photogrammetric tracking of the acquisition systems in use.A series of simulations was performed to evaluate the accuracy of our method in three configurations chosen to represent a variety of cultural heritage objects.These simulations show that we can achieve a spatial tracking accuracy of 0.020 mm and an angular accuracy of 0.100 mrad using four 5 Mpx cameras when digitizing an area of 400 mm x 700 mm. The accuracy of the final registration relies on the success of a series of optical and geometrical calibrations and their stability for the duration of the full acquisition process.The accuracy of the tracking and registration was extensively tested in laboratory settings. We first evaluated the potential for multiview 3D registration. Then, the method was used for to project of multispectral images on 3D models.Finally, we used the registered data to improve the reflectance estimation from the multispectral datasets
Abou, Fadel Maya. "Apports de la chimiométrie à la spectroscopie de Résonance Paramagnétique Electronique : nouvelles perspectives de traitement de données spectrales à dimensions spatiales (imagerie) et/ou temporelles". Thesis, Lille 1, 2015. http://www.theses.fr/2015LIL10130/document.
Electron Paramagnetic Resonance (EPR) Spectroscopy has undoubtedly become the first-choice technique for the characterization of complex materials containing some unpaired electrons (transition metal ions, rare earth ions, defects, organic radicals ...). Similarly to nuclear magnetic resonance spectroscopy, EPR generates multidimensional (2D, 3D…) spectral and recently also spatial (imaging) data as well as spectral/spatial ones. It is thus, surprising that despite the large amount of spectral data to be explored and complexity of the EPR signals, there hardly exist at the international level of exploitation the multivariate data processing methods that are widely available in chemometrics. The objective of this thesis is thus, to develop new tools for the treatment of these EPR spectral data, to establish new analytical methodologies and to evaluate their performance. The two main areas that will be studied are spectroscopic imaging and time-resolved spectroscopy. In this work, we will show that the implementation of the methods known as "multivariate curve resolutions" can extract, simultaneously, and without a priori all chemical maps and their corresponding spectra of pure compounds present in the studied sample. This methodology will also be exploited to extract the EPR spectra of intermediate species during a kinetic monitoring
Nardecchia, Alessandro. "Chemometric exploration in hyperspectral imaging in the framework of big data and multimodality". Electronic Thesis or Diss., Université de Lille (2022-....), 2022. https://pepite-depot.univ-lille.fr/LIBRE/EDSMRE/2022/2022ULILR021.pdf.
Nowadays, it is widely known that hyperspectral imaging is a very good tool used in many chemical-related research areas. Indeed, it can be exploited for the study of samples of different nature, whatever the spectroscopic technique used. Despite the very interesting characteristics related to this kind of acquired data, various limitations are potentially faced. First of all, modern instruments can generate a huge amount of data (big datasets). Furthermore, the fusion of different spectroscopic responses on the same sample (multimodality) can be potentially applied, leading to even more data to be analyzed. This aspect can be a problem, considering the fact that if the right approach is not used, it could be complicated to obtain satisfying results or even lead to a biased vision of the analytical reality of the sample. Obviously, some spectral artifacts can be present in a dataset, and so the correction of these imperfections has to be taken into account to carry out good outcomes. Another important challenge related to the use of hyperspectral image analysis is that normally, the simultaneous observation of spectral and spatial information is almost impossible. Clearly, this leads to an incomplete investigation of the sample of interest. Chemometrics is a modern branch of chemistry that can perfectly match the current limitations related to hyperspectral imaging. The purpose of this PhD work is to give to the reader a series of different topics in which many challenges related to hyperspectral images can be overcome using different chemometric facets. Particularly, as it will described, problems such as the generation of big amount of data can be faced using algorithms based on the selection of the purest information (i.e., SIMPLISMA), or related to the creation of clusters in which similar components will be grouped (i.e., KM clustering). In order to correct instrumental artifacts such as saturated signals will be used a methodology that exploits the statistical imputation, in order to recreate in a very elegant way the missing information and thus, obtain signals that otherwise would be irremediably lost. A significant part of this thesis has been related to the investigation of data acquired using LIBS imaging, a spectroscopic technique that is currently obtaining an increasing interest in many research areas, but that, still, has not really been exploited to its full potential by the use of chemometric approaches. In this manuscript, it will be shown a general pipeline focusing on the selection of the most important information related to this kind of data cube (due to the huge amount of spectral data that can be easily generated) in order to overcome some limitations faced during the analysis of this instrumental response. Furthermore, the same approach will be exploited for the data fusion analysis, related to LIBS and other spectroscopic data. Lastly, it will be shown an interesting way to use wavelet transform, in order to not limit the analysis only to spectral data, but also to spatial ones, to obtain a more complete chemical investigation
Istiqomah, Istiqomah. "Solides organiques dans les petits corps glacés : approches expérimentales et interprétation des données spectrales issues de mission VIRTIS/Rosetta". Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALU006.
The Rosetta space mission explored comet 67P/Churyumov-Gerasimenko between July 2014 and September 2016. During two years, extensive mappings in the visible and infrared ranges have been achieved by the VIRTIS imaging spectrometer (Visible InfraRed Thermal Imaging Spectrometer). This instrument has revealed a very dark and reddish surface, which has been interpreted by the presence of a dark carbonaceous material mixed up with opaque minerals (presumable Fe-Ni alloys and pyrrhotite). VIRTIS has also revealed, for the first for a comet, a broad band at 3.2 µm. The nature of this band was unclear at the beginning of this thesis, and two main semi-volatile compounds were suspected: ammonium salts and carboxylic acids.In this thesis, we have investigated these two hypotheses through laboratory experiments. We first conducted FTIR transmission experiments on pure solid carboxylic acids and ammonium salts. In a second step, we collected reflectance spectra of analogs of the refractory crust. A particular attention was devoted to the production of such analogs, and we developed dedicated grinding and mixing protocols. We found that the most suitable analogs are those produced from the sublimation of ice + refractory + semi-volatile mixtures in a vacuum chamber. They account well for the fine-grained and highly porous cometary material. Our experiments show that the 3.2 µm band in VIRTIS spectra is consistent with the presence of ammonium salts, which are ubiquitous across the surface of the comet. These ammonium salts constitute a new reservoir of nitrogen in comet, which might at least partially account for the missing nitrogen in comets.The abundance of the ammonium salt could however not be determined. Our experiments reveal the lack of between the band depth and the ammonium abundance in the samples, pointing that the parameters that control the band depth are not elucidated yet. This result points to the difficult question of the characterization of the porous texture of the sublimation residues and of their complex geometries. The grain size distribution is definitely only one parameter among other ones, and future studies should focus on this point. At last, the modeling approaches based on Hapke models are definitely not suitable for these dark semi-volatile bearing materials, and great care should be devoted with values published so far in literature
Laberdesque, Romain. "Etude des propriétés spectrales et spatiales de réflecteurs et coupleurs résonants". Thesis, Toulouse, INSA, 2016. http://www.theses.fr/2016ISAT0047/document.
The study is focused on the spectral and spatial properties of resonant grating structures. Resonant gratings in cavity are identified as structures allowing the fabrication of small-area and efficient reflectors and couplers. A model based on coupled mode theory has been developped, enabling fast modeling and design of this kind of structures. Thanks to this model we improved our understanding of the spectral and spatial properties of resonant gratings in cavity. In particular, we have established the relationship between the structure's geometry and the spectral and spatial properties of the modes which efficiently interact with the structures when used as reflectors or as couplers. The design of coupling structures with high-quality factor and controlled spatial profiles on cm-sized surfaces has been studied. Two axis of research are presented: structures composed of several cavities and structures composed by one large cavity. The later ones allow a better control of the spatial properties both in intensity and phase. We demonstrate that these structures have a high potential for holography. Design of such structures with low contrast index is also considered, particularly the design and fabrication of polymer-based waveguiding structures
Mahieu, Benoît. "Cohérence, accordabilité, propriétés spectrales et spatiales de sources de lumière extrême-ultraviolette femtoseconde". Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00967018.
Vezin, Philippe. "Caractéristiques spatiales et spectrales de la réponse instationnaire d’un écoulement turbulent en canal". Grenoble INPG, 1995. http://www.theses.fr/1995INPG0134.
Fauvel, Mathieu. "Méthodes spatiales et spectrales pour la classification de zones urbaines en imagerie satellitaire". Grenoble INPG, 2007. http://www.theses.fr/2007INPG0138.
Ln this work, we have investigated the difficult problem of classification of remote sensing data over urban area with high spatial resolution. Two strategies have been proposed. The fmt one is based on a two step-approach: in a fust step, spatial and spectral features are extracted and the classification is done according to the extracted feature in the second step. Morphological processing, such as geodesic opening and closing, have been used to extract spatial and spectral features. For the classification the support vector machine have been used. A novel kemel has been defmed that use both the spectral and spatial information during the classification step. The second strategy is based on data fusion. We proposed a fusion scheme, using fuzzy logic modeling, to fuse the outputs of several classifiers appplied on different data set from a same location. Conflict and uncertainty are solved using estimated of confidence. Experimental results on real data set shown superior accuracy compare to standard approach when using our proposed method
Scholl, Isabelle. "Conception, réalisation et utilisation d'archives de données solaires spatiales". Paris 6, 2003. http://www.theses.fr/2003PA066303.
Ternynck, Camille. "Contributions à la modélisation de données spatiales et fonctionnelles : applications". Thesis, Lille 3, 2014. http://www.theses.fr/2014LIL30062/document.
In this dissertation, we are interested in nonparametric modeling of spatial and/or functional data, more specifically based on kernel method. Generally, the samples we have considered for establishing asymptotic properties of the proposed estimators are constituted of dependent variables. The specificity of the studied methods lies in the fact that the estimators take into account the structure of the dependence of the considered data.In a first part, we study real variables spatially dependent. We propose a new kernel approach to estimating spatial probability density of the mode and regression functions. The distinctive feature of this approach is that it allows taking into account both the proximity between observations and that between sites. We study the asymptotic behaviors of the proposed estimates as well as their applications to simulated and real data. In a second part, we are interested in modeling data valued in a space of infinite dimension or so-called "functional data". As a first step, we adapt the nonparametric regression model, introduced in the first part, to spatially functional dependent data framework. We get convergence results as well as numerical results. Then, later, we study time series regression model in which explanatory variables are functional and the innovation process is autoregressive. We propose a procedure which allows us to take into account information contained in the error process. After showing asymptotic behavior of the proposed kernel estimate, we study its performance on simulated and real data.The third part is devoted to applications. First of all, we present unsupervised classificationresults of simulated and real spatial data (multivariate). The considered classification method is based on the estimation of spatial mode, obtained from the spatial density function introduced in the first part of this thesis. Then, we apply this classification method based on the mode as well as other unsupervised classification methods of the literature on hydrological data of functional nature. Lastly, this classification of hydrological data has led us to apply change point detection tools on these functional data
Rigaux, Philippe. "Interfaces visuelles et multi-représentation dans les bases de données spatiales". Paris, CNAM, 1995. http://www.theses.fr/1995CNAM0207.
Da, Silva Sébastien. "Fouille de données spatiales et modélisation de linéaires de paysages agricoles". Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0156/document.
This thesis is part of a partnership between INRA and INRIA in the field of knowledge extraction from spatial databases. The study focuses on the characterization and simulation of agricultural landscapes. More specifically, we focus on linears that structure the agricultural landscape, such as roads, irrigation ditches and hedgerows. Our goal is to model the spatial distribution of hedgerows because of their role in many ecological and environmental processes. We more specifically study how to characterize the spatial structure of hedgerows in two contrasting agricultural landscapes, one located in south-Eastern France (mainly composed of orchards) and the second in Brittany (western France, \emph{bocage}-Type). We determine if the spatial distribution of hedgerows is structured by the position of the more perennial linear landscape features, such as roads and ditches, or not. In such a case, we also detect the circumstances under which this spatial distribution is structured and the scale of these structures. The implementation of the process of Knowledge Discovery in Databases (KDD) is comprised of different preprocessing steps and data mining algorithms which combine mathematical and computational methods. The first part of the thesis focuses on the creation of a statistical spatial index, based on a geometric neighborhood concept and allowing the characterization of structures of hedgerows. Spatial index allows to describe the structures of hedgerows in the landscape. The results show that hedgerows depend on more permanent linear elements at short distances, and that their neighborhood is uniform beyond 150 meters. In addition different neighborhood structures have been identified depending on the orientation of hedgerows in the South-East of France but not in Brittany. The second part of the thesis explores the potential of coupling linearization methods with Markov methods. The linearization methods are based on the use of alternative Hilbert curves: Hilbert adaptive paths. The linearized spatial data thus constructed were then treated with Markov methods. These methods have the advantage of being able to serve both for the machine learning and for the generation of new data, for example in the context of the simulation of a landscape. The results show that the combination of these methods for learning and automatic generation of hedgerows captures some characteristics of the different study landscapes. The first simulations are encouraging despite the need for post-Processing. Finally, this work has enabled the creation of a spatial data mining method based on different tools that support all stages of a classic KDD, from the selection of data to the visualization of results. Furthermore, this method was constructed in such a way that it can also be used for data generation, a component necessary for the simulation of landscapes
Da, Silva Sébastien. "Fouille de données spatiales et modélisation de linéaires de paysages agricoles". Electronic Thesis or Diss., Université de Lorraine, 2014. http://docnum.univ-lorraine.fr/prive/DDOC_T_2014_0156_DA_SILVA.pdf.
This thesis is part of a partnership between INRA and INRIA in the field of knowledge extraction from spatial databases. The study focuses on the characterization and simulation of agricultural landscapes. More specifically, we focus on linears that structure the agricultural landscape, such as roads, irrigation ditches and hedgerows. Our goal is to model the spatial distribution of hedgerows because of their role in many ecological and environmental processes. We more specifically study how to characterize the spatial structure of hedgerows in two contrasting agricultural landscapes, one located in south-Eastern France (mainly composed of orchards) and the second in Brittany (western France, \emph{bocage}-Type). We determine if the spatial distribution of hedgerows is structured by the position of the more perennial linear landscape features, such as roads and ditches, or not. In such a case, we also detect the circumstances under which this spatial distribution is structured and the scale of these structures. The implementation of the process of Knowledge Discovery in Databases (KDD) is comprised of different preprocessing steps and data mining algorithms which combine mathematical and computational methods. The first part of the thesis focuses on the creation of a statistical spatial index, based on a geometric neighborhood concept and allowing the characterization of structures of hedgerows. Spatial index allows to describe the structures of hedgerows in the landscape. The results show that hedgerows depend on more permanent linear elements at short distances, and that their neighborhood is uniform beyond 150 meters. In addition different neighborhood structures have been identified depending on the orientation of hedgerows in the South-East of France but not in Brittany. The second part of the thesis explores the potential of coupling linearization methods with Markov methods. The linearization methods are based on the use of alternative Hilbert curves: Hilbert adaptive paths. The linearized spatial data thus constructed were then treated with Markov methods. These methods have the advantage of being able to serve both for the machine learning and for the generation of new data, for example in the context of the simulation of a landscape. The results show that the combination of these methods for learning and automatic generation of hedgerows captures some characteristics of the different study landscapes. The first simulations are encouraging despite the need for post-Processing. Finally, this work has enabled the creation of a spatial data mining method based on different tools that support all stages of a classic KDD, from the selection of data to the visualization of results. Furthermore, this method was constructed in such a way that it can also be used for data generation, a component necessary for the simulation of landscapes
Benhalouche, Fatima Zohra. "Méthodes de démélange et de fusion des images multispectrales et hyperspectrales de télédétection spatiale". Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30083/document.
In this thesis, we focused on two main problems of the spatial remote sensing of urban environments which are: "spectral unmixing" and "fusion". In the first part of the thesis, we are interested in the spectral unmixing of hyperspectral images of urban scenes. The developed methods are designed to unsupervisely extract the spectra of materials contained in an imaged scene. Most often, spectral unmixing methods (methods known as blind source separation) are based on the linear mixing model. However, when facing non-flat landscape, as in the case of urban areas, the linear mixing model is not valid any more, and must be replaced by a nonlinear mixing model. This nonlinear model can be reduced to a linear-quadratic/bilinear mixing model. The proposed spectral unmixing methods are based on matrix factorization with non-negativity constraint, and are designed for urban scenes. The proposed methods generally give better performance than the tested literature methods. The second part of this thesis is devoted to the implementation of methods that allow the fusion of multispectral and hyperspectral images, in order to improve the spatial resolution of the hyperspectral image. This fusion consists in combining the high spatial resolution of multispectral images and high spectral resolution of hyperspectral images. The implemented methods are designed for urban remote sensing data. These methods are based on linear-quadratic spectral unmixing techniques and use the non-negative matrix factorization. The obtained results show that the developed methods give good performance for hyperspectral and multispectral data fusion. They also show that these methods significantly outperform the tested literature approaches
Courault, Dominique. "Etude de la degradation des etats de surface du sol, par teledetection : analyses spectrales, spatiales et diachroniques". Paris 6, 1989. http://www.theses.fr/1989PA066119.
Courault, Dominique. "Etude de la dégradation des états de surface du sol par télédétection : analyses spectrales, spatiales et diachroniques /". Grignon : Institut national agronomique, 1989. http://catalogue.bnf.fr/ark:/12148/cb35073356p.
Baghi, Quentin. "Optimisation de l’analyse de données de la mission spatiale MICROSCOPE pour le test du principe d’équivalence et d’autres applications". Thesis, Paris Sciences et Lettres (ComUE), 2016. http://www.theses.fr/2016PSLEO003/document.
The Equivalence Principle (EP) is a cornerstone of General Relativity, and is called into question by the attempts to build more comprehensive theories in fundamental physics such as string theories. The MICROSCOPE space mission aims at testing this principle through the universality of free fall, with a target precision of 10-15, two orders of magnitude better than current on-ground experiments. The satellite carries on-board two electrostatic accelerometers, each one including two test-masses. The masses of the test accelerometer are made with different materials, whereas the masses of the reference accelerometer have the same composition. The objective is to monitor the free fall of the test-masses in the gravitational field of the earth by measuring their differential accelerations with an expected precision of 10-12 ms-2Hz-1/2 in the bandwidth of interest. An EP violation would result in a characteristic periodic difference between the two accelerations. However, various perturbations are also measured because of the high sensitivity of the instrument. Some of them are well defined, e.g. gravitational and inertial gradient disturbances, but others are unmodeled, such as random noise and acceleration peaks due to the satellite environment, which can lead to saturations in the measurement or data gaps. This experimental context requires us to develop suited tools for the data analysis, which are applicable in the general framework of linear regression analysis of time series.We first study the statistical detection and estimation of unknown harmonic disturbances in a least squares framework, in the presence of a colored noise of unknown PSD. We show that with this technique the projection of the harmonic disturbances onto the WEP violation signal can be rejected. Secondly we analyze the impact of the data unavailability on the performance of the EP test. We show that with the worst case before-flight hypothesis (almost 300 gaps of 0.5 second per orbit), the uncertainty of the ordinary least squares is increased by a factor 35 to 60. To counterbalance this effect, a linear regression method based on an autoregressive estimation of the noise is developed, which allows a proper decorrelation of the available observations, without direct computation and inversion of the covariance matrix. The variance of the constructed estimator is close to the optimal value, allowing us to perform the EP test at the expected level even in case of very frequent data interruptions. In addition, we implement a method to more accurately characterize the noise PSD when data are missing, with no prior model on the noise. The approach is based on modified expectation-maximization (EM) algorithm with a smooth assumption on the PSD, and use a statistical imputation of the missing data. We obtain a PSD estimate with an error less than 10-12 ms-2Hz-1/2. Finally, we widen the applications of the data analysis by studying the feasibility of the measurement of the earth's gravitational gradient with MICROSCOPE data. We assess the ability of this set-up to decipher the large scale geometry of the geopotential. By simulating the signals obtained from different models of the earth's deep mantle, and comparing them to the expected noise level, we show that their features can be distinguished
Raynaud, Jean-Louis. "Exploitation simultanée des données spatiales et fréquentielles dans l'identification modale linéaire et non-linéaire". Besançon, 1986. http://www.theses.fr/1987BESA2013.
Toutant, Steve. "Établissement d'une procédure d'acquisition et d'assemblage de données spatiales adaptée au laboratoire mobile Atlantis. Vers une chaîne de traitements intégrés de données spatiales en santé environnementale". Thesis, Université Laval, 2004. http://www.theses.ulaval.ca/2004/22313/22313.pdf.
Anjum, Adeel. "Publication de données qui préserve la vie privée pour des données continues et dynamiques: Les approches d'indexation spatiales et de bucketization". Phd thesis, Université de Nantes, 2013. http://tel.archives-ouvertes.fr/tel-00960547.
Semaan, Thierry. "Caractéristiques spectrales et pulsationnelles d'étoiles Be à l'aide de données sol (VLT/GIRAFFE et X-SHOOTER) et espace (CoRoT)". Observatoire de Paris (1667-....), 2012. https://hal.science/tel-02095134.
Be stars are early-type stars having near critical rotation. They are surrounded by an equatorial disc fed by discrete mass-loss ejections from the central star. Be stars are good laboratories to study, on one hand, the impact of rotation on pulsations and, on the other hand, the role of pulsation on the recurrent mass ejections. During this thesis we focused on faint Be stars located in the first exoplanetary fields CoRoT satellite. In a first step we have identified the stars presenting the Be phenomenon among all the variable stars observed by CoRoT. We have thus been able to provide a sample of forty Be stars. Thanks to ground-based spectroscopic observations at VLT with GIRAFFE and X-SHOOTER instruments we have studied th spectral properties of half of them and determined their fundamental parameters by taking into account the effects of rapid rotation. Using the CoRoT light curves we have determined the frequencies and amplitudes of the pulsations that characterize the treated stars and studied their temporal variations. We have studied attentively the newly discovered stars presenting light outbursts. Thanks to the carried spectroscopic and photometric studies we have been able to investigate the properties of pulsations according to the stellar location in the HR diagram, and could identify some common properties among the Be stars of our sample
Brahem, Mariem. "Optimisation de requêtes spatiales et serveur de données distribué - Application à la gestion de masses de données en astronomie". Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLV009/document.
The big scientific data generated by modern observation telescopes, raises recurring problems of performances, in spite of the advances in distributed data management systems. The main reasons are the complexity of the systems and the difficulty to adapt the access methods to the data. This thesis proposes new physical and logical optimizations to optimize execution plans of astronomical queries using transformation rules. These methods are integrated in ASTROIDE, a distributed system for large-scale astronomical data processing.ASTROIDE achieves scalability and efficiency by combining the benefits of distributed processing using Spark with the relevance of an astronomical query optimizer.It supports the data access using the query language ADQL that is commonly used.It implements astronomical query algorithms (cone search, kNN search, cross-match, and kNN join) tailored to the proposed physical data organization.Indeed, ASTROIDE offers a data partitioning technique that allows efficient processing of these queries by ensuring load balancing and eliminating irrelevant partitions. This partitioning uses an indexing technique adapted to astronomical data, in order to reduce query processing time
Duboisset, Magali. "Un système de contraintes d'intégrité OCL pour les bases de données spatiales". Phd thesis, Clermont-Ferrand 2, 2007. http://www.theses.fr/2007CLF21797.
Minout, Mohammed. "Modélisation des aspects temporels dans les bases de données spatiales". Doctoral thesis, Universite Libre de Bruxelles, 2007. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210672.
Etant donné ces nouveaux besoins, cette thèse se focalise sur la modélisation et l'implantation des aspects temporels dans bases de données. En effet, la conception d'une application de base de données se fait par un enchaînement de trois phases (conceptuelle, logique et physique). Au niveau conceptuel, plusieurs modèles conceptuels ont été proposés intégrant les caractéristiques temporelles et spatiales.
Malheureusement, au niveau logique, les modèles de données des SGBD actuels n'offrent pas les concepts nécessaires pour implanter le modèle conceptuel spatio-temporel. Nous proposons donc de nouvelles règles de traductions d'un schéma conceptuel, basé sur le modèle MADS (Modélisation des Applications à des données spatio-temporelles), en un schéma logique MADSLog pour les modèles cibles à savoir :relationnel et relationnel-objet. Chaque règle transforme un concept structurel, temporel et spatial du modèle MADS en un ou plusieurs concepts supportés par la cible. Par exemple, la propriété spatiale définissant la géométrie d'un type d'objet est traduite par la création d'un nouvel attribut de type spatial dans ce type d'objet. Un outil CASE(Computer-Aided Software Engineering) appelé Schema Translateur est développé dans cette thèse implémentant toutes les règles de traductions.
La traduction de schémas conceptuels en schémas logiques peut impliquer une perte sémantique en raison de la différence de la puissance d'expression entre le modèle conceptuel et le modèle de données des SGBD existants. D'où la nécessité de générer un ensemble de contraintes d'intégrité afin de préserver la sémantique définie dans le schéma conceptuel. Ces contraintes sont exprimées à ce niveau par des formules logiques.
Avec l'apparition de GML (Geographic Markup Language ) qui est conçu pour la modélisation, le transport et le stockage d'informations géographiques. Nous transformons également le schéma conceptuel MADS en GML. De nouveaux schémas GML temporel et spatial sont définis qui peuvent être employés par n'importe application de base de données spatio-temporelle.
Au niveau physique, nous proposons une méthode d'adaptation du schéma logique en schéma physique pour le modèle relationnel-objet.
Elle permet de définir les tables, les types abstraits, les types d'objets, les domaines, etc. Notre proposition permet aussi la génération des contraintes d'intégrité au niveau physique. En effet, chaque contrainte d'intégrité (structurelle, temporelle ou spatiale) qui est définie en calcul logique est exprimée soit directement par des contraintes déclaratives ou soit par des déclencheurs du SGBD choisi. Les déclencheurs spatiaux sont fondés sur les fonctionnalités prédéfinies dans Oracle, alors que les déclencheurs temporels sont basés sur les opérateurs et méthodes appliquées sur les types temporels.
Enfin, la traduction de requêtes est une deuxième clef de cette recherche. Le but de la traduction de requêtes, exprimées en algèbre, étant de reconstituer l'information au sens MADS à partir de la base de données stockées dans le SGDB cible. Elle permet de traduire les expressions algébriques MADS, qui sont définies sur le schéma conceptuel et non sur le schéma physique, en requêtes opérationnelles qui peuvent être exécutées sur une base de données spatiale et temporelle sous un SGBD ou un SIG.
Doctorat en sciences appliquées
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Duhamel, Jean-René. "Le traitement des données spatiales dans les champs corporel et péricorporel : une étude neuropsychologique". Aix-Marseille 2, 1987. http://www.theses.fr/1987AIX22084.
GAERTNER, JEAN-CLAUDE. "Organisation des assemblages demersaux dans le golfe du lion : structures spatiales et stabilite temporelle". Aix-Marseille 2, 1997. http://www.theses.fr/1997AIX22067.
King, Christine. "Étude des sols et des formations superficielles par télédétection : approche de leurs caractéristiques spectrales, spatiales et temporelles dans le visible et le proche infra-rouge /". Orléans : Bureau de recherches géologiques et minières, 1985. http://catalogue.bnf.fr/ark:/12148/cb349022146.
Pascal, Rémi. "Le peuplement du bassin méditerranéen de 1800 à 2010 : données disponibles, limites et organisations spatiales". Thesis, Avignon, 2020. http://www.theses.fr/2020AVIG1202.
The Mediterranean Sea and the surrounding lands have had a central role in the history of the world. These spaces, inhabited or traveled, have greatly evolved over the past millennia, and have gradually structured through the appearance of various geographical objects such as towns, cities, administrative divisions... It is at the crossroads of these spatial, historical, and human settlement dynamics, which is understood as the notion of settlement. To analyze its evolution around the Mediterranean from 1800 to 2010, a database of more than 137 000 localities distributed in all riparian states was built. But are they all "Mediterranean"?The delimitation of the Mediterranean area is an old and recurrent question always present in the researches on this space. To try to answer it, five variables were chosen to construct an index that allowed to propose a limit characterizing the Mediterranean localities. From this set of objects, and taking into account the notion of path dependence, an analysis of the evolution of the population around the Mediterranean Sea was carried out. Revealing cycles, trajectories and various other phenomena, it has brought to light forms of original space organizations
Ollier, Sébastien. "Des outils pour l'intégration des contraintes spatiales, temporelles et évolutives en analyse des données écologiques". Lyon 1, 2004. http://www.theses.fr/2004LYO10293.
Favetta, Franck. "Ambiguïtés dans les langages visuels d'interrogation spatiale et précision topologique des bases de données spatiales". Marne-la-Vallée, 2003. http://www.theses.fr/2003MARN0156.
Today, a growing panel of users has access to Information Systems and spatial datas, as Geographical Information Systems. This panel includes an increasing number of non-experts users. This fact implies a big need of user-friendly interfaces. In the domain of spatial queries, visual languages rightly meet this requirement. Nevertheless, visual languages suffer from important ambiguities that make them hard to use. Concerning the spatial expressive power, certain queries need a better topological precision than a description of the set of relations between two objects. These issues are linked and the topological expressive power can also meet problems of inconsistency. In order to solve these problems, a taxonomy of ambiguities has been built and solutions have been tested with potential users. A notion a ternary topological models has also been introduced. Especially, a model called 27 Intersections model, which extends an existing model, provides a high precision between three regions and guaranties consistency of their relations. Beyond query languages, ternary models are useful for image description, particularly in the field of medical image description in which a model has been proposed. Integration of the 27 Intersections model in OpenGIS has been presented
Bernard, Jérémy. "Signature géographique et météorologique des variations spatiales et temporelles de la température de l'air au sein d'une zone urbaine". Thesis, Ecole centrale de Nantes, 2017. http://www.theses.fr/2017ECDN0006.
This thesis presents a method to model air temperature differences within a conurbation . It relies on the analysis of the existing relationships between urban microclimate,geographical context and weather conditions. To do so, five air temperature networks located in three western France conurbations are utilized : Nantes, Angers and La Roche sur-Yon. A state of the art of the methods used to analyze urban climate is realized in chapter 1. In Chapter 2, air temperature networks are presented and analyzed and a methodology to correct biased data is proposed. In Chapter3 air temperature differences observed between the network sites are modelled from multiple linear regressions, using weather variables such as wind speed or solar radiation as explicative variables. Before the calibration step, data is sorted in a variety of ways in order to elaborate several models. The most performant model is identified in chapter4, confronting data observed using the five temperature networks to data estimated from each of the models.Chapter 5 illustrates the results of the work through three practical applications
Angeletti, Mélodie. "Traitement de données multi-spectrales par calcul intensif et applications chez l'homme en imagerie par résonnance magnétique nucléaire". Thesis, Université Clermont Auvergne (2017-2020), 2019. http://www.theses.fr/2019CLFAC004/document.
As a non-invasive technology for studying brain imaging, functional magnetic resonance imaging (fMRI) has been employed to understand the brain underlying mechanisms of food intake. Using liquid stimuli to fake food intake adds difficulties which are not present in fMRI studies with visual stimuli. This PhD thesis aims to propose a robust method to analyse food stimulated fMRI data. To correct the data from swallowing movements, we have proposed to censure the data uniquely from the measured signal. We have also improved the normalization step of data between subjects to reduce signal loss.The main contribution of this thesis is the implementation of Ward's algorithm without data reduction. Thus, clustering the whole brain in several hours is now feasible. Because Euclidean distance computation is the main part of Ward algorithm, we have developed a cache-aware algorithm to compute the distance between each pair of voxels. Then, we have parallelized this algorithm for three architectures: shared-memory architecture, distributed memory architecture and NVIDIA GPGPU. Once Ward's algorithm has been applied, it is possible to explore multi-scale clustering of data. Several criteria are considered in order to evaluate the quality of clusters. For a given number of clusters, we have proposed to compute connectivity maps between clusters or to compute Pearson correlation coefficient to identify brain regions activated by the stimulation
Oudin, Brugère Marie-France. "Variations spatiales et temporelles des données Landsat MSS : l'analyse en composantes principales appliquées à leur étude". Paris 1, 1987. http://www.theses.fr/1987PA010501.
Study of the landsat mss data stability, spatial on images coming from the same view and temporal on images coming from different views of the same area. The processing methodology is principal campanents analysis wich permits to reduce to two channels the basic four channels information without modifying the initial spatial order of the points. It is proposed for application with simplified modalities and criteria allowing the validity check. The study considers the statistical parameters wich appear at each step of the process and the luminance - chrominance visualisations got from the two first transformed channels wich contain the most part of the initial information. The results show that the karhunen - loeve basis remains stable in space and time. Though the proposed methodology appears to be an easy usable tool permitting to establish a final document (the color image) well adapted to a macroscopic interpretation of the images for geographical studies
Gabriel, Edith. "Détection de zones de changement abrupt dans des données spatiales et application à l'agriculture de précision". Montpellier 2, 2004. http://www.theses.fr/2004MON20107.
Zinger, Svitlana. "Interpolation et rééchantillonnage de données spatiales et application à la cartographie urbaine et à la détermination du fond cosmique primordial". Phd thesis, Télécom ParisTech, 2004. http://pastel.archives-ouvertes.fr/pastel-00000944.
Rodes, Arnau Isabel. "Estimation de l'occupation des sols à grande échelle pour l'exploitation d'images d'observation de la Terre à hautes résolutions spatiale, spectrale et temporelle". Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30375/document.
The new generation Earth observation missions such as Sentinel-2 (a twin-satellite initiative prepared by the European Space Agency, ESA, in the frame of the Copernicus programme, previously known as Global Monitoring for Environment and Security or GMES) and Venµs, jointly developed by the French Space Agency (Centre National d'Études Spatiales, CNES) and the Israeli Space Agency (ISA), will revolutionize present-day environmental monitoring with the yielding of unseen volumes of data in terms of spectral richness, temporal revisit and spatial resolution. Venµs will deliver images in 12 spectral bands from 412 to 910 nm, a repetitivity of 2 days, and a spatial resolution of 10 m; the twin Sentinel-2 satellites will provide coverage in 13 spectral bands from 443 to 2200 nm, with a repetitivity of 5 days, and spatial resolutions of 10 to 60m. The efficient production of land cover maps based on the exploitation of such volumes of information for large areas is challenging both in terms of processing costs and data variability. In general, conventional methods either make use of supervised approaches (too costly in terms of manual work for large areas), target specialised local models for precise problem areas (not applicable to other terrains or applications), or include complex physical models with inhibitory processing costs. These existent present-day approaches are thus inefficient for the exploitation of the new type of data that the new missions will provide, and a need arises for the implementation of accurate, fast and minimally supervised methods that allow for generalisation to large scale areas with high resolutions. In order to allow for the exploitation of the previously described volumes of data, the objective of this thesis is the conception, design, and validation of a fully automatic approach that allows the estimation of large-area land cover with high spatial, spectral and temporal resolution Earth observation imagery, being generalisable to different landscapes, and offering operational computation times with simulated satellite data sets, in preparation of the coming missions
Haboudane, Driss. "Intégration des données spectrales et géomorphométriques pour la caractérisation de la dégradation des sols et l'identification des zones desusceptibilité à l'érosion hydrique". Thèse, Université de Sherbrooke, 1999. http://savoirs.usherbrooke.ca/handle/11143/2705.
Declercq, Charlotte. "Conception et développement d'un service web de mise à jour incrémentielle pour les cubes de données spatiales". Thesis, Université Laval, 2008. http://www.theses.ulaval.ca/2008/25814/25814.pdf.
Haboudane, Driss. "Intégration des données spectrales et géomorphométriques pour la caractérisation de la dégradation des sols et l'identification des zones de susceptibilité à l'érosion hydrique". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0031/NQ61854.pdf.
Reboud, Christophe. "Analyse des peuplements d'oiseaux à partir de données atlas : variations spatiales et temporelles de la répartition des espèces". Dijon, 2001. http://www.theses.fr/2001DIJOS039.
Koffi, Kouao Jean. "Analyse des structures spatiales des données de distribution phytogéographique des Acanthaceae en Afrique centrale". Doctoral thesis, Universite Libre de Bruxelles, 2008. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210497.
Phytogeographic data reflect the spatial variability of plant diversity and constitute consequently a potential tool for conservation policy development. In order to stimulate and valorise the concept of phytogeographic systems, this dissertation entitled “Analysis of the spatial pattern of phytogeographic data of Acanthaceae in Central Africa” aims (1) to analyse the spatial distribution of the Acanthaceae family in Central Africa (Democratic Republic of the Congo, Rwanda, Burundi); (2) to compare this distribution with the known phytogeographic theories of Robyns (1948), White (1979, 1986) and Ndjele (1988); (3) to use the spatial distribution models as a tool for evaluating the human impact on landscapes and diversity; (4) to identify potential indicator species of the phytogeographic territories; (5) to evidence the phenomenon of vicariance; and (6) to quantify the impact of the fragmentation of forested landscapes in central Africa. In this study, two levels of spatial resolution have been considered: the phytogeographic systems themselves and a system of grid cells. A geographic information system has been used to draw maps of the spatial distribution of every species. The choice to analyse the Acanthaceae family of the herbarium of the National Botanical Garden of Belgium (BR) has been justified by the systematic revision of this collection and by its huge number of samples. The data set contained 9181 samples, collected between 1888 and 2001 by about 427 collectors in the Democratic Republic of the Congo, Rwanda and Burundi ;the samples represented 48 genera, 310 species and 6362 geographic positions. The maps showing the spatial distribution of all samples pooled evidenced the different levels of exploration of the study area. Certain phytogeographic territories have been explored more intensely than others. The mostly explored zones, consequently also denoted as the most diverse ones, were the Afromontane regional centre of endemism, including the regional mosaic of Lake Victoria, and the Zambezian regional center of endemism. Species distribution maps evidenced the spatial patterns of species presence. Certain species showed an overall distribution while others were clearly bound to particular territories. The latter species, denoted as “unique species” or “characteristic species” could be used as bio-indicators to stimulate and valorise the concept of the phytogeographic systems in the framework of conservation policy development. By means of the Acanthaceae family, it has been shown that the impact of forest fragmentation will be considerable; species bound to a specific phytogeographic zone are assumed vulnerable; they will disappear when their biotopes are destroyed. The potential distribution of the species, based on the geographic position of the samples and on environmental data, have been generated in order to describe more precisely the ecological niches of the species involved and to detect cases of vicariance. Two types of vicariance have been found using the phytogeographic territories of Robyns (1948) and White (1979, 1986) at the genus and the species levels: ecological vicariance and geographic vicariance; the former type involves species or subspecies observed in the same phytogeographic region while the latter type involves species and subspecies not found in the same territory. This analysis enabled us to identify zones of speciation. A cluster analyses showed that the spatial distribution of the Acanthaceae data corresponded more closely to the phytogeographic system of White (1979, 1986), than to those proposed by Robyns (1948) or Ndjele (1988). In order to valorise our approach, the current methodology should also be applied to other families widely collected in the Democratic Republic of the Congo, Rwanda and Burundi, such as the Rubiaceae or Mimosoideae families, this (1) to synchronise all data bases for a more profound understanding of the degree of exploration and of the existence of species with a limited ecological amplitude (unique species), and (2) to enable the identification of zones that should be prioritised for conservation.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished
Carlut, Julie. "Caractéristiques spatiales et temporelles du champ magnétique terrestre à l'échelle des temps géologiques (10⁴-10⁶ ans) : nouvelles données paléomagnétiques et modélisation". Paris 7, 1998. http://www.theses.fr/1998PA077192.
Thomas, Claire. "Fusion d'images de résolutions spatiales différentes". Phd thesis, École Nationale Supérieure des Mines de Paris, 2006. http://pastel.archives-ouvertes.fr/pastel-00002097.
Zeitouni, Karine. "Analyse et extraction de connaissances des bases de données spatio-temporelles". Habilitation à diriger des recherches, Université de Versailles-Saint Quentin en Yvelines, 2006. http://tel.archives-ouvertes.fr/tel-00325468.
Mondo, Mélanie. "Traces numériques et dimensions spatiales des pratiques de la ville touristique". Thesis, La Rochelle, 2022. http://www.theses.fr/2022LAROS019.
This thesis explores the inputs and the impact of digital footprints on the understanding of the spatial dimensions of urban tourist practices. Digital footprints are an emerging field of investigation that promises a better understanding of service stakeholders’ expectations (businesses, institutions, academic). From heat maps to dashboards, data is collected, processed, aggregated, smoothed, and synthetized into visualizations that could reveal a new tourist space-time. Applying frameworks from tourism geography and critical data studies, we suggest a critical approach to analyze the way these data are used. A review of the existing literature confirms an uptrend in digital footprints usage / monitoring, identifies what is at stake regarding the observation of tourist cities and points out critical limits. Two complementary approaches are then presented to measure the concrete value of this data regarding the space-time of urban tourist practices. In Biarritz (France), the analysis of a given social media dataset highlights the need for a contextualized analysis of footprints. In La Rochelle (France), a GPS dataset complemented with a series of interviews reveal the potential of elicitation methods to better understand digital footprints and narrate the practice of the tourist city. Eventually, these two approaches confirm our initial hypothesis i.e. digital footprints tend to enrich, under specific conditions, the understanding of tourism practices. The outcomes obtained allow us to advocate the relevance of contextualized and qualitative research on digital footprints in geography
Chambodut, Aude. "Le champ magnétique terrestre : structures spatiales et variations temporelles vues par les ondelettes". Paris, Institut de physique du globe, 2004. https://tel.archives-ouvertes.fr/tel-00008021.
Jaara, Kusay. "Prise en compte des dépendances entre données thématiques utilisateur et données topographiques lors d’un changement de niveau de détail". Thesis, Paris Est, 2015. http://www.theses.fr/2015PEST1013/document.
With the large availability of reference topographic data, creating geographic data is not exclusive to experts of geographic information any more. More and more users rely on reference data to create their own data, hereafter called thematic data. Reference data then play the role of support for thematic data. Thematic data make sense by themselves, but even more by their relations with topographic data. Not taking into account the relations between thematic and topographic data during processes that modify the former or the latter may cause inconsistencies, especially for processes that are related to changing the level of detail. The objective of this thesis is to define a methodology to preserve the consistency between thematic and topographic when the level of detail is modified. This thesis focuses on the adaptation of thematic data after a modification of topographic data: we call this process thematic data migration. We first propose a model for the migration of punctual thematic data hosted by a network. This model is composed of: (1) a model to describe the referencing of thematic data on topographic data using spatial relations (2) a method to re-locate thematic data based on these relations. The approach consists in identifying the expected final relations according to the initial relations and the modifications of topographic data between the initial and the final state. The thematic data are then re-located using a multi-criteria method in order to satisfy, as much as possible, the expected relations. An implementation is presented on toy problems and on a real use case provided by a French public authority in charge of road network management. The extension of the proposed model to take into account the relations for other applications than thematic data migration is also discussed
Lazrak, El Ghali. "Fouille de données stochastique pour la compréhension des dynamiques temporelles et spatiales des territoires agricoles. Contribution à une agronomie numérique". Phd thesis, Université de Lorraine, 2012. http://tel.archives-ouvertes.fr/tel-00782768.