Rozprawy doktorskie na temat „Extraction de surfaces d'eau”
Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych
Sprawdź 50 najlepszych rozpraw doktorskich naukowych na temat „Extraction de surfaces d'eau”.
Przycisk „Dodaj do bibliografii” jest dostępny obok każdej pracy w bibliografii. Użyj go – a my automatycznie utworzymy odniesienie bibliograficzne do wybranej pracy w stylu cytowania, którego potrzebujesz: APA, MLA, Harvard, Chicago, Vancouver itp.
Możesz również pobrać pełny tekst publikacji naukowej w formacie „.pdf” i przeczytać adnotację do pracy online, jeśli odpowiednie parametry są dostępne w metadanych.
Przeglądaj rozprawy doktorskie z różnych dziedzin i twórz odpowiednie bibliografie.
Gasnier, Nicolas. "Use of multi-temporal and multi-sensor data for continental water body extraction in the context of the SWOT mission". Electronic Thesis or Diss., Institut polytechnique de Paris, 2022. http://www.theses.fr/2022IPPAT002.
Pełny tekst źródłaSpaceborne remote sensing provides hydrologists and decision-makers with data that are essential for understanding the water cycle and managing the associated resources and risks. The SWOT satellite, which is a collaboration between the French (CNES) and American (NASA, JPL) space agencies, is scheduled for launch in 2022 and will measure the height of lakes, rivers, and oceans with high spatial resolution. It will complement existing sensors, such as the SAR and optical constellations Sentinel-1 and 2, and in situ measurements. SWOT represents a technological breakthrough as it is the first satellite to carry a near-nadir swath altimeter. The estimation of water levels is done by interferometry on the SAR images acquired by SWOT. Detecting water in these images is therefore an essential step in processing SWOT data, but it can be very difficult, especially with low signal-to-noise ratios, or in the presence of unusual radiometries. In this thesis, we seek to develop new methods to make water detection more robust. To this end, we focus on the use of exogenous data to guide detection, the combination of multi-temporal and multi-sensor data and denoising approaches. The first proposed method exploits information from the river database used by SWOT (derived from GRWL) to detect narrow rivers in the image in a way that is robust to both noise in the image, potential errors in the database, and temporal changes. This method relies on a new linear structure detector, a least-cost path algorithm, and a new Conditional Random Field segmentation method that combines data attachment and regularization terms adapted to the problem. We also proposed a method derived from GrabCut that uses an a priori polygon containing a lake to detect it on a SAR image or a time series of SAR images. Within this framework, we also studied the use of a multi-temporal and multi-sensor combination between Sentinel-1 SAR and Sentinel-2 optical images. Finally, as part of a preliminary study on denoising methods applied to water detection, we studied the statistical properties of the geometric temporal mean and proposed an adaptation of the variational method MuLoG to denoise it
Daye, Mirna. "Etude de la contamination par le mercure dans les milieux aquatiques : devenir et comportement biogéochimique, mise au point de méthodes d’analyse de trace du mercure". Thesis, Lille 1, 2013. http://www.theses.fr/2013LIL10074/document.
Pełny tekst źródłaMercury is a very particular element conferred by its high density and vapor pressure. It is a ubiquitous element in the environment and considered as global pollutant. Mercury is among the most hazardous environmental pollutants, given by its organic form, methylmercury (MeHg or CH3Hg). In natural waters, mercury is present at very low concentrations. For this reason, most analytical techniques do not achieve accurate direct measurement of Hg which necessitates preconcentration to meet their limit of detection. The first part of this study focuses on the development of analytical methods for the measurement of mercury by solid phase extraction. Two analytical methods have been developed; one based on the anion exchange mechanism using ICP-MS (Inductively Coupled Plasma Mass Spectrometry) and the other one based on the solid phase extraction of mercury using 5-phenylazo-8- hydroxyquinoline and detection by CV-AFS (Cold Vapor Atomic Fluorescence Spectroscopy). Part of this work also includes the distribution and biogeochemical behavior of mercury in rivers of the Deûle and Lys (Northern France). The results have showed high concentrations of total mercury (HgT) in the Deûle contaminated by a former smelter "Metaleurop". The concentrations of HgT measured in the Lys are much lower. Although Deûle sediments are highly burdened with HgT as compared to Lys sediments, much higher percentage of methylmercury is found in Lys River. Suspended particles are the major Hg carrier phase and transporters of Hg pollution from Deûle to Lys River
Delestre, Olivier. "Simulation du ruissellement d'eau de pluie sur des surfaces agricoles". Phd thesis, Université d'Orléans, 2010. http://tel.archives-ouvertes.fr/tel-00587197.
Pełny tekst źródłaDutailly, Bruno. "Plongement de surfaces continues dans des surfaces discrètes épaisses". Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0444/document.
Pełny tekst źródłaIn the context of archaeological sciences, 3D images produced by Computer Tomography scanners are segmented into regions of interest corresponding to virtual objects in order to make some scientific analysis. These virtual objects are often used for the purpose of performing accurate measurements. Some of these analysis require extracting the surface of the regions of interest. This PhD falls within this framework and aims to improve the accuracy of surface extraction. We present in this document our contributions : first of all, the weighted HMH algorithm whose objective is to position precisely a point at the interface between two materials. But, applied to surface extraction, this method often leads to topology problems on the resulting surface. So we proposed two other methods : The discrete HMH method which allows to refine the 3D object segmentation, and the surface HMH method which allows a constrained surface extraction ensuring a topologically correct surface. It is possible to link these two methods on a pre-segmented 3D image in order to obtain a precise surface extraction of the objects of interest These methods were evaluated on simulated CT-scan acquisitions of synthetic objects and real acquisitions of archaeological artefacts
Nicod, Jean-Marc. "Extraction de surfaces en imagerie medicale : approches paralleles". Lyon, École normale supérieure (sciences), 1997. http://www.theses.fr/1997ENSL0053.
Pełny tekst źródłaGondrand, Cécile Prat Marc Quintard Michel. "Analyse des transferts d'eau dans les micropiles à combustible". Toulouse : INP Toulouse, 2007. http://ethesis.inp-toulouse.fr/archive/00000421.
Pełny tekst źródłaDesroches, Damien. "Extraction de hauteurs d'eau géolocalisées par interférométrie radar dans le cas de SWOT". Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30030/document.
Pełny tekst źródłaThe SWOT mission (Surface Water and Ocean Topography), conducted by CNES and JPL, and scheduled for launch in 2020, is a major step forward for spaceborne altimetry, both for oceanography and continental hydrology. It is the first interferometric SAR mission whose specific objective is the measurement of water surface height. The main instrument of the mission, KaRIn, a Ka-band Radar Interferometer, has particular characteristics: very low incidence angle (from 0.6 to 3.9°), short wavelength (8.6 mm), and short baseline (10 m). This technical configuration leads to properties that are specific to SWOT, both in terms of phenomenology and data processing. Moreover, due to the nature and the huge volume of data, new processing methods, different from those used in previous interferometric mission, are considered. For the Low Rate (LR) mode dedicated to oceanography, a large part of the processing will take place onboard to limit the data volume transmitted to ground. The High Rate (HR) mode, mainly targeting continental hydrology, also present original characteristics in terms of processing, essentially conducted on ground, due to the large diversity in the structure of the observed water surfaces. In both modes, the strategy for conversion of phase into geolocated heights cannot be directly based on those of previous missions, relying on spatial phase unwrapping. The approach retained here is to use, as far as possible, a reference Digital Terrain Model (DTM) to remove the phase ambiguity and proceed directly to height inversion. This allows both to reduce the computing time and to avoid the need for ground control points, which are difficult to obtain both over oceans and continental surfaces, due to varying water level and very low signal-to-noise ratio over land. For cases where the precision of reference DTM is not good enough to ensure a correct phase unwrapping, methods to detect and reduce the errors are proposed. To facilitate the use of the geolocated heights derived from the interferometric phase in HR mode, we propose a method that permits to significantly improve the geolocation of the products, without degrading the water height information
Boisot, Olivier. "Étude de la rétrodiffusion des surfaces d'eau en bande Ka à faible incidence". Thesis, Toulon, 2015. http://www.theses.fr/2015TOUL0008/document.
Pełny tekst źródłaThe evolution of the altimetric techniques from Ku-band to Ka-band and the wide swath al-timetry in the context of the SWOT mission (« Surface Water Ocean Topography », CNES/NASA) raises new scientific questions about the validity of the backscattering models from water sur-faces in such a frequency band and errors in estimating water heights from time-evolving water surfaces. A backscattering model (GO4) adapted to the SWOT configuration is introduced. It preserves the accuracy of the referencial Physical Optics model while maintaining the simplicity of the clas-sical Optical Geometrics model. In addition to the classical slope parameter, it introduces another parameter called as « effective curvature » (msc). This model allows the inverson of the surface slope and curvature parameters under certain conditions which are developped in this manus-cript. The joint validity of the backscattering models in Ka-band and from water surfaces is che-cked from controlled wind-wave tank radar measurements . In a last part, the temporal properties of the backscattered signal is studied, in particular the correlation time and the Doppler shift induced by waves motion. Influence of the latters on the non focused SAR synthesis is studied in the context of the SWOT system
Boisot, Olivier. "Étude de la rétrodiffusion des surfaces d'eau en bande Ka à faible incidence". Electronic Thesis or Diss., Toulon, 2015. http://www.theses.fr/2015TOUL0008.
Pełny tekst źródłaThe evolution of the altimetric techniques from Ku-band to Ka-band and the wide swath al-timetry in the context of the SWOT mission (« Surface Water Ocean Topography », CNES/NASA) raises new scientific questions about the validity of the backscattering models from water sur-faces in such a frequency band and errors in estimating water heights from time-evolving water surfaces. A backscattering model (GO4) adapted to the SWOT configuration is introduced. It preserves the accuracy of the referencial Physical Optics model while maintaining the simplicity of the clas-sical Optical Geometrics model. In addition to the classical slope parameter, it introduces another parameter called as « effective curvature » (msc). This model allows the inverson of the surface slope and curvature parameters under certain conditions which are developped in this manus-cript. The joint validity of the backscattering models in Ka-band and from water surfaces is che-cked from controlled wind-wave tank radar measurements . In a last part, the temporal properties of the backscattered signal is studied, in particular the correlation time and the Doppler shift induced by waves motion. Influence of the latters on the non focused SAR synthesis is studied in the context of the SWOT system
Sedji, Maryse Iris. "Adhésion, inactivation et persistance des adénovirus dans des biofilms d'eau potable". Thesis, Université de Lorraine, 2019. http://www.theses.fr/2019LORR0200.
Pełny tekst źródłaAlthough drinking water outbreaks due to enteric viruses are scarce, they highlight their ability to spread and persist in drinking water systems. There is a lack of knowledge about virus behaviour into water distribution systems while this information is critical to improve treatment procedures. Among enteric viruses, adenoviruses show a high prevalence in the environment especially in drinking water, at least for their genome. In this context, the accumulation of adenovirus serotype 2 (HAdV-2) and bacteriophage PR772, used as a surrogate for adenoviruses, was studied using pilots fed with drinking water. We aimed to study virus accumulation on high-density polyethylene (HDPE) surfaces colonized or not by young drinking water biofilms and to evaluate the role of this biofilm in virus persistence during chlorine disinfection. We first developed an ICC-qPCR method to quantify infectious adenoviruses in environmental water samples. This method also improved the quantification of infectious adenoviruses at the laboratory scale. Before pilot experiments, the physicochemical characteristics of both viruses and surfaces were studied. HAdV-2 had the largest size, hydrodynamic diameter and hydrophobicity and phage PR772 showed the highest charge density. The biofilm led to a decrease in hydrophobicity but an increase in roughness. The two viruses behaved differently with a consistently higher accumulation rate for HAdV-2. The accumulation of phage PR772 was significantly reduced by the presence of a biofilm which accentuated the difference between the two viruses. When chlorination (10 mg/L) was applied on viruses either in suspension or accumulated in biofilm, HAdV-2 appeared as the most sensitive. The sensitivity of both viruses to chlorine decreased in presence of a biofilm showing its protective role against this oxidant. Our results confirm the role of hydrophobicity, particularly on the location of virus, but the charge density is probably involved in viral accumulation on surfaces as well
Gondrand, Cécile. "Analyse des transferts d'eau dans les micropiles à combustible". Phd thesis, Toulouse, INPT, 2006. http://oatao.univ-toulouse.fr/7543/1/gondrand.pdf.
Pełny tekst źródłaEl, Ghoul Aymen. "Phase fields for network extraction from images". Nice, 2010. http://www.theses.fr/2010NICE4075.
Pełny tekst źródłaThis thesis describes the construction of an undirected network (e. G. Road network) model, based on the recently developed higher-order active contours (HOACs) and phase fields, and introduces a new family of phase field HOACs for directed networks (e. G. Hydrographic networks in remote sensing imagery, vascular networks in medical imagery). In the first part of this thesis, we focus on the stability analysis of a HOAC energy leading to a “phase diagram”. The results which are confirmed by numerical experiments enable the selection of parameter values for the modeling of indirectly networks. Hydrographic networks, unlike road networks, are directed, i. E. They carry a unidirectional flow in each branch. This leads to specific geometric properties of the branches and particularly of the junctions that it is useful to capture in model, for network extraction purposes. We thus develop a nonlocal phase field model of directed networks, which, in addition to a scalar field representing a region by its smoothed characteristic function and interacting no locally so as to favor network configurations, contains a vector field representing the “flow” through the network branches. The vector field is strongly encouraged to be zero outside, and of unit magnitude inside the network ; running along the network branches ; and to have a zero divergence. This prolongs network, controls width variation along a branch ; and produces asymmetric junctions for which total incoming branch width approximately equals total outgoing branch width. The new proposed model is applied to the problem of hydrographic network extraction from very high resolution satellite images, and it outperforms the undirected network model
Thiévenaz, Virgile. "Impact et solidification de gouttes d'eau". Thesis, Sorbonne université, 2019. https://tel.archives-ouvertes.fr/tel-03358455.
Pełny tekst źródłaWhenever a water drop impacts a cold surface – whose surface temperature is lower than 0°C – it freezes as it spreads. The solidification slows the drop's spreading down, eases its fragmentation into droplets, leads to the liquid's retraction and gives the frozen drop a certain shape. The nature of the cold surface is crucial in the freezing process. Starting from the Stefan problem, we developed a model for the solidification dynamics, which takes into account the thermal diffusion within the substrate. This model yields a better appreciation of the influence of the substrate's thermal properties – its temperature and thermal effusivity – over the liquid's rate of freezing. It enables us to quantitatively predict the dynamics of solidification, and therefore to study the freezing of a drop during its impact. As regards the drop's spreading, we demonstrated that the effect of freezing could be assimilated to that of viscosity, as it slows the flow down. We showed that the fragmentation of a drop at low temperature was due to an increase in the density of air. Once spread, the drop is trapped by the ice, which hinders its retraction. We established a link between the shape of the spread drop and the duration of its trapping. Finally, we showed that the competition between the retraction of liquid water on ice and its freezing led to the different patterns observed
Labouyrie-Rouillier, Laurence. "Extraction et caractérisation des matières organiques naturelles dissoutes d'eaux de surface : étude comparative des techniques de filtration membranaire et d'adsorption sur résines macroporeuses non ioniques". Poitiers, 1997. http://www.theses.fr/1997POIT2347.
Pełny tekst źródłaLeigh, Nathan D. "On the velocities of ions produced at surfaces /". free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3012996.
Pełny tekst źródłaGuillot, Sophie. "Le polyéthylène réticulé (PER) : relations structures - migrations, migrations au contact d'eau chaude". Montpellier 1, 2004. http://www.theses.fr/2004MON13510.
Pełny tekst źródłaLachaud, Jacques-Olivier. "Extraction de surfaces à partir d'images tridimensionnelles : approche discrète et approche par modèle déformable". Phd thesis, Université Joseph Fourier (Grenoble), 1998. http://tel.archives-ouvertes.fr/tel-00004892.
Pełny tekst źródłaArdon, Roberto. "Extraction de surfaces dans des images 3D et chemins minimaux : applications en imagerie médicale". Paris 9, 2005. https://portail.bu.dauphine.fr/fileviewer/index.php?doc=2005PA090010.
Pełny tekst źródłaPelleïeux, Sandra. "Intéraction de bactériophages avec des surfaces colonisées par des biofilms d'eau potable et évaluation de protocoles de nettoyage". Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0082/document.
Pełny tekst źródłaAlthough pathogens remain widely uncommon in water distribution networks, they may constitute a real threat for human health when accidentally introduced in the system. There is a lack of knowledge about virus behaviour into water distribution systems whereas such information is critical for a better viral risk management. In this context, three F-specific RNA bacteriophages -MS2, GA and Qbeta- were used as models, in experimental conditions mimicking water distribution systems. The purpose of the present work was at first to compare the viral accumulation of bacteriophages on high-density polyethylene (HDPE) colonised or not with drinking water biofilms. The second objective was to evaluate, on phages adsorbed in the biofilm, the efficiency of a cleaning protocol, based on chlorination and increase in the hydrodynamic strengths. To sum up, the water velocities tested in this work had little influence on both the bacterial and virus accumulation on surfaces, but applying a water flow led to an increase in the number of adsorbed phages in comparison with hydrostatic conditions. Whatever the conditions (water velocity, colonisation or not with a biofilm) MS2 phage was found to be the less adherent one. On HDPE colonised with a two-month old biofilm, the adhesion sequence was consistent with the sequence of hydrophobicity of the phages. The chlorination protocol tested in our study (4 to 5 mg CL2/L) can be applied punctually in distribution networks. After 60 minutes of chlorination the log-reduction was about 0.7 log10 for bacteria and between 2 and 3 log10 for bacteriophages, while no more infectious phages were detected in water after 5 minutes. Those results highlight that even two-month-old biofilms provide to viruses a protection against disinfection protocol. At last, the chlorination appears to be more efficient to inactivate viruses adsorbed on surfaces than an increase in the water flow velocity
Boutaleb, Nadia. "Étude de la formation de biofilms sur les surfaces de matériaux couramment utilisés dans les canalisations d'eau potable". Lorient, 2007. http://www.theses.fr/2007LORIS099.
Pełny tekst źródłaThe biofilms developed in drinking water pipelines pose a real problem of public health in addition of other corrosion phenomena or pressure losses. Improving our understanding of the mechanisms which are involved in bacterial adhesion to abiotic supports, must allow developing new strategies of fight against the biofilms. Our work constitutes a contribution to the comprehension of the mechanisms implied in the process of bioadhesion to the drinking water pipelines through the evaluation of the physicochemical surfaces properties (hydrophobicity, acid-base character and surface charges) and structural characterisation of the bacterial membrane as well as tests of adhesion. The impact of environmental factors such as the pH, the ionic force or the presence of chlorine is investigated on surface physicochemical properties of bacteria to allow a better understanding of the respective role played by the non-specific interactions in the adhesion phenomena. These results are completed by a structural analysis by infrared spectroscopy which reveals which membrane components are primarily implicated in the bacterial adaptation to the physicochemical changes of the medium. Attempts to correlate the theoretical approach “XDLVO” to the results of adhesion tests on various supports of drinking water pipelines are performed. This allows evaluating its efficacy to predict the bioadhesion and the types of interactions implicated during this process. Finally, the structural adaptation, the organization and the architecture of the biofilm developed under various physico-chemical and hydrodynamic conditions are evaluated in “dynamic mode” by infrared spectroscopy and confocal microscopy. This dynamic study allows proposing an early marker of colonisation which could help in the water networks monitoring
Hajri, Souhail. "Modélisation des surfaces rocheuses naturelles à partir d'une scannerisation laser 3D et extraction automatique de formes caractéristiques : applications aux spéléothèmes et surfaces géologiques". Grenoble, 2010. http://www.theses.fr/2010CHAMS039.
Pełny tekst źródłaThe research work presented in this dissertation concems 3d image processing. We are interested in the automation's tasks of the extraction and the characterization of reliefs fomms in the naturel environment from 3D point clouds acquired by LIDAR. Once thèse data are reconstructed as triangular meshes or TIN models (Triangular Irregular Networks), we are particularly interest in the 3D TIN model segmentation that is one of the essentiel stops of the pattern recognition process. The goal of segmentation is to décompose the TIN model into homogeneous régions with common characteristics that correspond to significant geological objects. However, the images to be processed are relatively complex (natural fomms), and thus req ui red a priori knowledge. Th us, we have initial ly proposed a method for interactive segmentation based on knowledge of the operator. The method involves manually marking the regions of interest in the models to extract the desired geological fomms. This approach is based on the watershed method. Later, a second segmentation solution, more automated is proposed. This solution is focused on two objects which we know perfectly its discriminating features: planar discontinuities and stalagmites. The identification and characterization process of planes discontinuities is based on the unsupervised clustering algorithm named DBSCAN which can automatically extract parameters related to the discontinuities of rock surfaces: orientation, spacing, roughness. . . The second approach, which aims the automatic identification and characterization, is based on ellipse fitting
Rassinoux-Trouvé, Adeline. "Ajustement de l'hydrophobicité de silices mésoporeuses organisées pour l'adsorption sélective de polluants organiques en présence d'eau". Poitiers, 2010. http://www.theses.fr/2010POIT2321.
Pełny tekst źródłaActivated carbons and hydrophobic microporous zeolites are usually used for the removal of organic pollutants in wastewater. An extended BET surface and a relevant pore volume both confer high sorption capacities to organised silica materials. Moreover, these solids exhibite a low water-adsorbent interaction at low P/P0 giving them an hydrophobic character. However, the presence of silanol groups limits the adsorption of organic molecules in aqueous phase. In order to significantly increase the mesoporous silica hydrophobicity, various modifications during synthesis (phenyl groups incorporation) or post-synthesis (grafting of trimethylsilyl, aminopropyl and mecaptopropyl groups) were considered. The grafting of trimethylsilyl groups and phenyl groups incorporation can therefore considerably reduce the hydrophilicity of these solids by reducing the number of silanol groups. In the case of gas adsorption, hydrophobicity proved to be a positive key factor. In aqueous phase, the non-polar organic pollutants adsorption also requires hydrophobic silica. For polar molecules, the grafting of polar groups (amino or sulfonic) increases the pollutant adsorption capacities
Carvalho, José. "Extraction automatique d'informations geomorphometriques (reseaux et surfaces enveloppes) a partir de modeles numeriques de terrain". Paris 7, 1995. http://www.theses.fr/1995PA077008.
Pełny tekst źródłaSalazar, Gonzalez Margarita. "Ecochimie et photoproduction de l'astaxanthine chez Haematococcus pluvialis (Flotow)". Aix-Marseille 3, 1995. http://www.theses.fr/1995AIX30014.
Pełny tekst źródłaClémençon, Boris. "Extraction des lignes caractéristiques géométriques des surfaces paramétrées et application à la génération de maillages surfaciques". Troyes, 2008. http://www.theses.fr/2008TROY0004.
Pełny tekst źródłaA major issue for meshing a given analytical surface is to guarantee the accuracy of the underlying geometry. This can be achieved in particular by adapting the mesh to the surface curvature. Without curvature adaptation, parasitic undulations appear in areas where the specified element size is locally large with respect to the minimum radius of curvature : this phenomenon is called aliasing. The classical approach to reduce this phenomenon is to locally decrease the edge size, at the cost of a greater number of elements. We propose to adapt the mesh to the geometry by locating the vertices and the edges along the ridges. These lines are the maxima of the principal curvatures in absolute value along their associated line of curvature. We present methods to characterize and extract the ridges in the case of a parametric surface. Singularities such as umbilics and extremal points are discussed. These vertices and discrete lines form a graph represented by a set of edges. Simplified polygonal lines representing significant ridges are extracted from this graph, interpolated and then integrated as internal curves in the parametric domain. The mesh of this parametric domain including these lines is generated and mapped onto the surface. Examples show that taking ridge lines into account avoids the aliasing without increasing the number of elements, and also reduces the gap between the surface and the mesh
Chavoor, Greg. "Light Extraction Enhancement of GaN Based LEDs Using Top Gratings, Patterned Sapphire Substrates, and Reflective Surfaces". DigitalCommons@CalPoly, 2012. https://digitalcommons.calpoly.edu/theses/737.
Pełny tekst źródłaLickes, Jean-Paul. "Contribution à l'étude de surfaces d'oxydes :corrélation entre le point de charge nulle et la thermodynamique d'adsorption de vapeur d'eau". Doctoral thesis, Universite Libre de Bruxelles, 1998. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/212074.
Pełny tekst źródłaMamoudou, Mohamadou. "Dynamique de transfert des matières organiques et inorganiques le long du continuum fluvial de la Garonne : impact de la retenue de Malause". Phd thesis, Toulouse, INPT, 2008. http://oatao.univ-toulouse.fr/7797/1/mamoudou.pdf.
Pełny tekst źródłaChen, Quan, i 陳全. "Efficient numerical modeling of random surface roughness for interconnect internal impedance extraction". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B3955708X.
Pełny tekst źródłaNguyen, Van sinh. "3 D Modeling of elevation surfaces from voxel structured point clouds extracted from seismic cubes". Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4069/document.
Pełny tekst źródłaReconstructing surfaces with data coming from an automatic acquisition technique always entails the problem of mass of data. This implies that the usual processes cannot be applied directly. Therefore, it leads to a mandatory data reduction process. An effective algorithm for a rapid processing while keeping the original model is a valuable tool for constructing an optimal surface and managing the complex data.In this dissertation, we present methods for building an optimal geological surface from a huge amount of 3D points extracted from seismic cubes. Applying the process to the whole set of points induces an important risk of surface shrinking so that the initial boundary extraction is an important step permitting a simplification inside the surface. The global surface shape will then be better kept for the reconstruction of the final triangular surface. Our proposals are based on the regularity of data which permits, even if data are missing, to easily obtain the neighboring information. Firstly, we present a new method to extract and simplify the boundary of an elevation surface given as voxels in a large 3D volume having the characteristics to be sparse. Secondly, a method for simplifying the surface inside its boundary is presented with a rough optional simplification step followed by a finer one based on curvatures. We also keep into consideration that the density of data must gradually change in order to receive in the last step a triangulated surface with better triangles. Thirdly, we have proposed a new and fast method for triangulating the surface after simplification
Petitpas, Benoit. "Extraction de paramètres bio-geo-physiques de surfaces 3D reconstruites par multi-stéréo-restitution d'images prises sans contraintes". Phd thesis, Université Paris-Est, 2011. http://tel.archives-ouvertes.fr/tel-00693326.
Pełny tekst źródłaPouget, Marc. "Geometry of surfaces : from the estimation of local differential quantities to the robust extraction of global differential features". Nice, 2005. http://www.theses.fr/2005NICE4052.
Pełny tekst źródłaThis research work relates to the geometrical aspects of mathematics, computer sciences and applications. This work is motivated by applications such as computer aided design, medical imaging, scientific computations and simulations or also virtual reality and multimedia. This thesis proposes an analysis of some local as well as global topics of the geometry of surfaces. From a local point of view, the problem is the estimation of the normal, the curvatures and quantities of higher order from points sampled on a smooth surface. From a global point of view, we analyze the lines of extreme curvature on surfaces, called ridges. On the one hand, a method for the estimation of local differential quantities with polynomial fitting is studied : the properties of convergence are established and an algorithm is proposed and implemented. On the other hand, algorithms are developed for the computation of the topology on the ridges for surfaces discretized by a mesh or parameterized. Precise conditions of sampling as wel as certified algorithm are given in the case of a surface, an implicit equation of the ridges is derived in the parametric domain and the singularities are analyzed for a polynomial parameterization. The equations are also polynomial, and specific methods of computer algebra are developed to compute the topology on the singular curve of the ridges
Portuguez, Etienne. "Gouttes millimétriques d'eau en milieu confiné : comportement au cours du séchage". Thesis, Limoges, 2016. http://www.theses.fr/2016LIMO0130/document.
Pełny tekst źródłaThis work aims at improving the understanding of the specific mechanisms of the drying of ceramic materials. This step is crucial when manufacturing a piece. Indeed, besides the optimization of the sample composition, the temperature and the relative humidity have to be controlled so that the weight loss andthe shrinkage do not cause any stress development, leading to cracks formation which can damage the final piece after a heat treatment. After a presentation of the different known drying mechanisms, this thesis highlights a set of measuring benches conceived within an instrumented climatic chamber. A firststudy concerning the behavior of the shaping liquid as a function of temperature and relative humidity isrealized. Then, this liquid is inserted between two parallel and identical substrates in order to reproduce the case of a liquid bridge within a pore. The hydrophilic and hydrophobic contacts are then studied.Finally, drying experiences are carried out on ceramic materials to correlate the different observations.The obtained results demonstrate the importance of a compromise when selecting the drying parameters.The temperature and the relative humidity not only influence the kinetics of the process during the liquiddeparture, but also modify the contact with the solid phase of the ceramic piece. At the end of drying, the rupture of liquid bridges is brutal and can explain some macroscopic phenomena observed when dryinglarge pieces
Tamime, Rahma. "Caractérisations optiques et microscopiques de la structure de membranes organiques d'ultrafiltration : application à la production d'eau potable". Thesis, Aix-Marseille 3, 2011. http://www.theses.fr/2011AIX30016.
Pełny tekst źródłaFor the better understanding of the effects of the use of coagulants on the performance of ultrafiltration organic membranes applied in the production of drinking water, a complete structural characterization (surface and bulk) from microscopic scale to macroscopic scale of the membranes (new, after filtration of coagulant and after chemical cleaning) is used. First, the structural properties of new flat-sheet PES membranes were determined as a function of MWCO. The characteristics of surface (pore size and recovery rate) determined by SEM and the features of bulk determined by speckle ellipsometry showed an increasing trend with MWCO. The use of WLI and AFM with different observation scales showed that the determination of the roughness of a membrane significantly depends on the observation scale. The AFM was able to differentiate membranes according to their MWCO as well as to the methods of manufacturing. Second, the impact of the nature of aluminum polychlorosulfate coagulants (PAX-XL 7A and Aqualenc F1) on the structural properties of PES 100 kDa membrane is addressed. The use of Hermia model and the analysis of multi-scale surface roughness showed that the filtration of suspensions of coagulants PAX-XL 7A or Aqualenc F1 produces a deposit on the surface through adsorption and/or precipitation of hydrolysis products of coagulant, causing a significant change in the surface morphology of the membrane. This structural modification is also revealed by the measurements of speckle of the light scattering. SEM and AFM analysis revealed a change in the state of surface of the membrane after cleaning of fouled membranes. An extension of the structural characterization techniques, in particular the AFM to the study of hollow fibers and their aging has shown a very interesting way of analysis
Rezai, Bidakhavidi Caminde. "Nouvelles solutions de préparation et d'activation des surfaces : assemblages époxy-fonte". Thesis, Bourgogne Franche-Comté, 2017. http://www.theses.fr/2017UBFCA021/document.
Pełny tekst źródłaOrganic coatings applied on the surface of cast iron pipes ensure very good chemical and anti-corrosion protection against aggressive effluents. To improve adherence between coating (epoxy) and substrate, a surface preparation is required. Among conventional processes shot blasting has emerged as the most efficient and cheapest solution for ensuring stripping while generating adapted roughness. However, as it may enhance both mechanical anchorage and chemical bonding a better understanding of these phenomena should be developed. Besides new eco-friendly alternatives were investigated.Indeed, new techniques were evaluated, i.e. laser structuring and an ultra-high pressure water jet whose major benefits are understanding the effect of ablation and surface roughness prior to applying a coating. Moreover, two other conventional processes (sand blasting and brushing) were introduced to obtain a various roughness.Results obtained were then analyzed to further understand bonding mechanisms at the interface.Several processes were then implemented to evaluate the surface morphology as well as the surface chemistry (spectroscopy Raman and XPS) correlated to the adhesion mechanisms
Baouche, Saoud. "Formation d'hydrogène moléculaire sur des surfaces d'intérêt astrophysique : premiers résultats sur des glaces d'eau à très basse température et sur le graphite à haute température". Paris 6, 2004. http://www.theses.fr/2004PA066361.
Pełny tekst źródłaJayarathne, Ayomi L. "Transformation of physical and chemical properties of metals built-up on urban road surfaces". Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/122560/1/Ayomi_Jayarathne_Thesis.pdf.
Pełny tekst źródłaBracou, Hervé. "Etude hydrodynamique d'une colonne d'extraction. Influence de la mouillabilité". Toulouse, INPT, 1995. http://www.theses.fr/1995INPT009G.
Pełny tekst źródłaGbeddy, Gustav Kudjoe Seyram. "Transformation and degradation of organic pollutants on urban road surfaces". Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/203905/15/9514791_gustav_gbeddy_thesis.pdf.
Pełny tekst źródłaDeschamps, Thomas. "Extraction de Courbes et Surfaces par Methodes de Chemins Minimaux et Ensembles de Niveaux. Applications en Imagerie Medicale 3D". Phd thesis, Université Paris Dauphine - Paris IX, 2001. http://tel.archives-ouvertes.fr/tel-00003335.
Pełny tekst źródłaLoustau, Emilie. "Effet des facteurs environnementaux sur la nature des EPS, la capacité de sorption du cuivre et le potentiel de résilience de biofilms phototrophes simplifiés". Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30148.
Pełny tekst źródłaPhototrophic biofilm, the main benthic signature of fast-flowing rivers, provide an important number of ecosystem services related to self-purification mechanisms (nitrates, pesticides, metal contaminations, etc.). However, their functioning is strongly disturbed by the increasing anthropogenic pressures, particularly by the presence of traces metals (TM) or the sequential interruption of surface flow. In the context of global change, the response of phototrophic communities should be considered for river management, in term of chemical and ecological properties. The aim of this thesis was to understand the physiological responses of benthic phototrophic microorganisms to environmental parameters involved in global change (light, temperature, phosphorus) as well as their response to a multi-stress combining the exposure of biofilms to TM (Cu and Zn, alone or in cocktail) by the prolonged drying of biofilm. Physiological responses of biofilm (biomass, photosynthetic activity and EPS production (extracellular polymeric substances)) were studied to analyze the tolerance and resilience capacities of communities. Three benthic phototrophic species were chosen: the cyanobacteria Phormidium autumnale, the diatom Nitzschia palea and the green algae Uronema confervicolum. Cultures of biofilm in free surface flow microcosms (hydraulic mini-channels) allowed to control all the experimental parameters. The first step was to develop a method for EPS extraction from the biofilm matrix while preserving the cell integrity of phototrophic microorganisms. Subsequently, the study of physiological responses of monospecific phototrophic biofilm exposed to Cu or/and Zn showed different sensitivities of phototrophic species. Then the sorption capacity of Cu by these species depended on environmental parameters, via the modulation of EPS production and composition. Finally, the double-stress characterised by Cu exposition followed by drying biofilm induced also resilience responses when rewetting, modulated by the environmental parameters. Overall, the monospecific phototrophic biofilms studied present different tolerance and resilience capacities by modifying the abundance and composition of EPS produced
Borget, Fabien. "Etude de l'adsorption de l'ozone et du cyanoacétylène sur une surface de glace d'eau : un modèle de chimie du milieu insterstellaire". Aix-Marseille 1, 2000. http://www.theses.fr/2000AIX11050.
Pełny tekst źródłaAndrieu, François. "Caractérisation des surfaces glacées de Mars par imagerie hyperspectrale : inversion du transfert radiatif". Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS178/document.
Pełny tekst źródłaMars has a complex climate, characterized by carbon dioxide and water cycles, and dust transport at all scales. These cycles are mainly controlled by the seasonal condensation of CO₂ and water ice deposits at high latitudes during the polar night and their sublimation during the local spring. There are a lot of interactions between the CO₂ , water and dust cycles on Mars and they influence each other. An active seasonal process illustrates particularly well these links: the cryoventing, cold CO₂ gas jets triggered by seasonal sublimation of CO₂ deposits, which can put dust from the regolith in suspension into the atmosphere durably, and whose activity seems to be modulated by the exchange of water at the surface.The purpose of this thesis is to allow the use of the available hyperspectral imaging data to their full potential, to bring new constraints on seasonal exchanges between surface and atmosphere and the interactions between the different cycles (CO₂ , water , dust), focusing on cold gas jets. To achieve this, a semi-analytical radiative transfer model in compact ices and an effective inversion method were developed and validated.The radiative transfer model describes the interaction of light with a surface quantitatively, using the following parameters: thickness of the layer, volume proportions and grain-sizes of impurities, surface roughness. It is based on several key assumptions: geometrical optics, piecewise-continuous media quasi-spherical inclusions. The two-stream approximation is used for the radiative transfer inside the layer, but the surface specular reflectance is estimated taking into account the variability of the facets orientations from the surface roughness. This model was validated both numerically and on laboratory data.The inversion method consists in exploring synthetic databases generated by the radiative transfer model and determining the most likely sets of parameters to reproduce a given measure. The inversion is based on the Bayesian formalism: the manipulated variables are described by probability density functions. This allows to take into account realistic uncertainties on the data and enables to calculate a posteriori uncertainties on the result of the inversion.A focused study was conducted on a area of particular interest, to test and prove the applicability of this approach to the massive inversion of spectro-imaging data. The dune-field of Richardson Crater (72°S, 180°W) was chosen because it shows strong interactions between the water and CO₂ cycles, a major seasonal cryoventing activity, but also a large amount of data available and a high quality temporal monitoring. The monitoring of surface characteristics on this site shows a decrease in the thickness of the ice during the spring consistently with climate models simulations. We were able to estimate and monitor the content of water and dust in order to discuss the formation scenario of cold jets
Nkouam, Gilles Bernard. "Conservation des fruits du karité (Vitellaria paradoxa Gaertn.) et de l'aiélé (Canarium schweinfurthii Engl.) : isothermes de sorption d'eau et extraction des matières grasses des fruits stockés". Thesis, Vandoeuvre-les-Nancy, INPL, 2007. http://www.theses.fr/2007INPL058N/document.
Pełny tekst źródłaThe static microgravimetric method permitted to observe that the Canarium pulp was more hygroscopic at 25°C than the sheanut kernels. On the other hand, sheanut kernel was more hygrocopic in the temperature range 35°C-55°C. The Oswin model best described the sorption data of the two products in the whole water activity range. Hysteresis was observed in the entire temperature range 25-55°C for sheanut kernel and Canarium pulp. It is suggested that these products should be stored in an environment with a relative humidity of 40-60%, in order to attain the recommended moisture content for storage. A model was adapted to predict the sorption isotherms of shea and Canarium below 25°C and above 55°C. The oil yields obtained with supercritical CO2 were lower than those obtained with hexane. The acid values of butter and oil extracted with carbon dioxide were greater than those of lipids extracted using hexane. The acid values of samples stored at 18°C were the largest. The iodine value of the oils decreased with an increase of the storage period, irrespective of the storage temperature and the solvent used for extraction. The extraction with CO2 did not extract linolenic acid. The proportion of free fatty acids increased when carbon dioxide was used for extraction. From the foregoing, it is suggested that storage at -33°C for up to 5 months presents the best means of preserving these products. Only fresh or fruits stored at -33°C should be used for the extraction of lipids using carbon dioxide. The products stored at 18°C were the most hard and the hardness was correlated negatively to the water content, but positively to the acid value of fatty material extracted
Furusho, Carina. "Modélisation hydrologique des bassins versants périurbains". Ecole centrale de Nantes, 2011. http://www.theses.fr/2011ECDN0035.
Pełny tekst źródłaThe greatest changes caused by the fast growing urbanization are concentrated in the transition between the cities and the countryside, in peri-urban areas. In order to enhance the knowledge and to reproduce the hydrological behavior of peri-urban rivers, new models must be developed. This PhD work takes part of the AVuPUR project (Assessing the Vulnerability of Peri-Urban Rivers). The objective of the project is to deliver adapted tools for quantifying the impact of artificial surfaces and urban structures within the catchments on its hydrological regime and pathways. The base model has first been developed by Météo France and it is part of a platform coupled to meteorological models that are used in both forecasts and research. Our contribution consists on the introduction of the main artificial elements, such as impervious surfaces and the sewer network, in order to represent urban zones water flow specific processes. The model is applied to the Chezine watershed, in the suburbs of Nantes, western France. A sensitivity analysis has been carried out, enhancing the comprehension on how the model works and also to identify the influence of each parameter on simulated discharges and on the components of the water budget. The model is tested under different land-use scenarios so that we could study the impact of urban zones in the simulated processes and on the annual water budget. Furthermore, the study evaluates the model capability of simulating and providing a hydrological analysis to compare different land-use scenarios
Nkouam, Gilles Bernard Dirand Michel Kapseu César Barth Danielle. "Conservation des fruits du karité (Vitellaria paradoxa Gaertn.) et de l'aiélé (Canarium schweinfurthii Engl.) isothermes de sorption d'eau et extraction des matières grasses des fruits stockés /". S. l. : S. l. : INPL ; Université de NGAOUNDERE, 2007. http://www.scd.inpl-nancy.fr/theses/2007_NKOUAM_G_B.pdf.
Pełny tekst źródłaTitre provenant de l'écran-titre.
Sieffert, Nicolas. "Importance des interfaces liquides-liquides: de l'extraction d'ions à la catalyse biphasique : Etudes par dynamique moléculaire avec des solvants moléculaires et des liquides ioniques". Université Louis Pasteur (Strasbourg) (1971-2008), 2007. http://www.theses.fr/2007STR13101.
Pełny tekst źródłaWe report molecular dynamics studies on interfaces between water and “classical” (chloroform, decene) or “green” (room temperature ionic liquids) immiscible liquids, in order to characterize the distribution of ionic and molecular species involved in two important processes in chemistry: the solvent extraction of ions (such as radioactive Cs+) and phase transfer catalysis (rhodium catalyzed hydroformylation of olefins). The results show analogies and differences between several hydrophobic phases, and allow us to understand, at the nanoscopic level, the mechanism of these complex processes in heterogeneous solutions
Subramanian, Bhargavi. "Exploring Neoteric Solvent Extractants: Applications in the Removal of Sorbates From Solid Surfaces and Regeneration of Automotive Catalytic Converters". Cincinnati, Ohio University of Cincinnati, 2007. http://www.ohiolink.edu/etd/view.cgi?ucin1178075024.
Pełny tekst źródłaTitle from electronic thesis title page (viewed July 12, 2007). Includes abstract. Keywords: Solvent extraction; Soils; Pentachlorophenol; Automobile catalytic converters; Metal chelating agents Includes bibliographical references.
Gao, Qi. "Estimation des ressources en eau sur les surfaces continentales par télédétection micro-onde multi-capteurs". Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30137.
Pełny tekst źródłaThe estimation of the water resources of the continental surfaces at a regional and global scale is fundamental for good water resources management. This estimation covers a wide range of topics and fields, including the characterisation of soils and water resources at the basin scale, hydrological modelling and flood prediction and mapping. In this context, the characterisation of the states of the continental surface, to obtain better input parameters for hydrological models, is essential to improve the precision in the simulation of flows, droughts, and floods. The estimation of the water content in the system, including the different water bodies and the free water in the soil, is especially necessary for a precise description of the hydrological processes and, in general, of the water cycle on the continental surfaces. To better characterise hydrological processes, human interventions cannot be neglected. Humans influence the water cycle, mainly through irrigation and the construction of reservoirs, which must be correctly quantified. The objective of the thesis is the improvement of the remote estimation of water resources, including the quantification of human factors, using several sensors recently launched, taking advantage of recent developments in remote sensing technology. With the arrival of the Sentinel constellations (Sentinel-1, 2, 3), we have better tools to estimate water resources, including human impacts, with greater precision and coverage. This thesis consists mainly of two parts where human interventions in the water cycle are considered: irrigation cartography (as an application of soil moisture), and the forcing of reservoirs in hydrological simulations (as an application of altimetry). Firstly, soil moisture is estimated from the statistical analysis of Sentinel-1 SAR data. Two methodologies are developed to obtain soil moisture with a spatial resolution of 100 m based on the interpretation of Sentinel-1 data collected with the VV polarization (vertical-vertical), which is combined with optical data of Sentinel-2 for the analysis of the effects of vegetation. Secondly, irrigation is mapped under various meteorological conditions, including high spatial and temporal resolution
Jantzi, Hugo. "Incision fluviale et transition d'une rivière alluviale vers une rivière à fond rocheux : formation et évolution des seuils molassiques de la moyenne Garonne toulousaine au cours du 20e siècle". Thesis, Toulouse 2, 2018. http://www.theses.fr/2018TOU20069/document.
Pełny tekst źródłaThe middle Garonne River has seen its morphology and hydro-sedimentary dynamics change significantly during the 20th century, resulting in channel narrowing and incision. This thesis proposes to analyze the vertical adjustments of the river since 1830 and the dynamics of the evolution of the knickpoints released from the alluvial cover under the effect of the incision. The study is based on a geohistorical and field approach, at three spatial scales: (1) the length of the middle Garonne, (2) three sections and (3) the knickpoints present at each section. At the linear scale, three phases of adjustments are identified: a first phase (1830-1860s) of aggradation (1.9 cm.an-1) and widening; a second phase (1860-1920) of aggradation (3.2 cm.an-1) and narrowing; then a third phase (1920-2000s) of incision (2.6 cm.an-1) and narrowing with an acceleration of the incision (3.6 cm.an-1) and narrowing from the 1960s. At the section scale, the major role of in-stream mining has been highlighted with regard to the outcropping of knickpoints by regressive and progressive erosion operating rapidly during the 1970s. At the scale of the knickpoints, the degradation of the molasse shows that once the alluvial cover is released, the incision remains active and the river continues its incision without major break in terms of speed between the two processes. Furthermore, the study of the erosion forms in the molasse highlights the importance of the fusion of the forms for the erosion and the evolution of the knickpoints, and tends to show that vertical erosion would not be the main factor for the development of the knickpoints. The mobility of the coarse load has also shown that the knickpoints are not an obstacle to the mobility of the pebbles during downstream transfer