In this study, hydrogeological modeling of the Somme river basin situated in the north of France was made with special emphasis on the stream-aquifer interaction. The coupled model developed at Ecole des Mines de Paris was used. Geographic Information Systems (GIS) tools were incorporated during all the stages of modeling process for both preparation of input data and visualization of the results of simulations. Initially, the process began with Digital Elevation Model (DEM) analysis. Afterwards, the surface and aquifer grids were generated by using nested grid generators and refinement was made on the stream network and subcatchment boundaries in order to increase the accuracy of numerical solution. In order to run the surface model, meteorological forcing, land use and soil type data were acquired. Surface model was used to partition the precipitation into evapotranspiration, infiltration and surface runoff components. A steady-state piezometric head distribution was computed by the groundwater model to serve as an initial condition to the coupled model. The flow in the unsaturated zone was simulated by using Nash cascade model. The unsteady groundwater and surface flow simulations were performed by taking into consideration the stream-aquifer interaction on a daily time step. The calibration and validation were realized by using the streamflow and piezometric head measurements distributed around the basin. The strong groundwater influence on the hydrology of the basin is well represented by the model. Comparisons of predicted flooded areas in year 2001 were made with other models and a satellite derived image. In the end, several sensitivity analyses were performed for several parameters concerning the groundwater flow.

Αυτή η εργασία έχει ως στόχο την περιβαλλοντική αξιολόγηση των δήμων του Νομού Αχαΐας με τη χρήση του GIS και των Ψηφιακών Υψομετρικών Μοντέλων Εδάφους(Ψ.Υ.Μ.Ε ή DEM). Τα παραπάνω δεδομένα μπορούν να χρησιμοποιηθούν σε περιπτώσεις εφαρμογών όπως: 1.Για κατασκευή ψηφιακών τοπογραφικών χαρτών 2.Για παραγωγή χαρτών σκιασμένου αναγλύφου (shaped relief maps),υψομέτρων,κλίσεων και εκθέσεων 3.Για ομαδοποίηση και καταμέτρηση χαρακτηριστικών αντικειμένων κατά κλάσεις υψομέτρων,κλίσεων και εκθέσεων 4.Για διευκόλυνση υδρολογικών μελετών (υδρογραφικό δίκτυο,όρια λεκάνης απορροής,κ.ά.) Επιπλέον,στο φυσικό περιβάλλον η μορφολογία εδάφους και οι καλύψεις της Γης μπορούν να βοηθήσουν στο σχεδιασμό(κόστος και τρόπος ανάπτυξης)ενός δικτύου κινητής ή σταθερής ασύρματης τηλεφωνίας αφού η διάδοση και η εμβέλεια του σήματος επηρεάζονται από αυτό. Στόχος της εργασίας αυτής είναι να ταξινομηθούν οι δήμοι του Ν.Αχαΐας βάση μορφολογικών παραμέτρων,να βρεθούν οι καλύψεις Γης από δορυφορικές φωτογραφίες και η ορατότητα των κεραιών βάση του DEM. / This work aims at assesing the environmental evaluation of municipalities of Prefecture Achaia with the use of GIS and Digital Hypsometric Models of Territory(DEM). The previous data can be used in cases of applications as: 1.For the manufacture of digital topographic maps 2.For the production of maps of shaded bas-relief(shaped relief maps),altitudes,bents and reports 3.For the regrouping and measurement of characteristic objects at age-groups of altitudes,bents and reports 4.For the facilitation of hydrologic studies (hydrographical network,limits of run-off plane,etc) Moreover,in the natural environment the morphology of soil and the covers of Earth can help in the planning(cost and way of growth)of a networkmobile or constant wireless telephony after the distribution and the scope of signal are influenced by this. The target of this work is to categorize the municipalities of Prefecture of Achaia base on morphological parameters,to find the covers of Earth from satelite photographs and the visibility of aerials base on DEM.

This study shows that remote sensing and GIS are powerful tools in identifying geologically induced lineaments from digitally enhanced ETM+ satellite imageries and the digital elevation model (DEM) in remote areas such as the Makran accretionary prism, southeast Iran. The presence of the conjugate shear fractures in the eastern part, along with the extensional, and the presence of reidal sets associated with the subsidiary fractures of the Minab-Zendal fault system in the western part, suggests that the structural pattern changes from pure shear to simple shear from east to the west across the prism. Moreover, the gradual increase in the value of the angle between the two conjugate shear fractures, from south (coastal Makran) to north across the prism, and the presence of high-angle north-dipping reverse faults, with few south-dipping normal faults, suggest that deformation changes from brittle, in the south, to ductile in the northern part of the prism.

No description available.

L'érosion est un phénomène d'arrachage et de transport de particules solides par des efforts hydrauliques au sein des ouvrages hydrauliques. Cette pathologie très représentée dans les ouvrages en terre peut conduire à la rupture, aussi, la comprendre et la maîtriser constituent des enjeux sociétaux et industriels très forts. L'érodabilité des matériaux se caractérise au travers notamment d'un essai dit d'érosion de conduit et sa modélisation numérique constitue le pivot de ce travail de thèse. Le phénomène d'érosion est un problème couplé entre le fluide et le solide et nous utiliserons deux codes construits sur des approches particulaires pour aborder le problème : ASPHODEL (ANDRITZLMFA) pour la partie fluide (méthode SPH-ALE Smoothed Particle Hydrodynamics - Arbitrary Lagrangian Eulerian) et YADE (L3S-R) pour la fraction solide (méthode DEM Discrete Element Method). Alors que YADE a été largement utilisé pour modéliser des problèmes géotechniques, ASPHODEL n'a pas encore été évalué dans un tel contexte. Ce travail constituera alors une étude de faisabilité pour l'utilisation d'ASPHODEL dans un contexte du génie civil et donnera les conditions pour espérer obtenir des résultats quantitatifs pour les phénomènes étudiés. Dans un deuxième temps, le couplage entre les deux codes sera construit dans le but d'étudier les phénomènes d'arrachage de particules le long de conduits formés à travers des matériaux granulaires cohérents. La validation du code ASPHODEL à l'échelle de la particule a été effectuée par l'étude de l'écoulement visqueux autour d'un objet 2D (cylindre) fixe et isolé de section circulaire mais aussi carrée ou triangulaire. Les forces de trainée, de portance, le coefficient de pression autour du cylindre et le nombre de Strouhal sont comparés à des résultats issus de la littérature pour différents Reynolds en régime laminaire. La validation du code ASPHODEL à l'échelle de l'échantillon a consisté à étudier un écoulement fluide entre des parois lisses ainsi que des parois constituées de particules solides fixes créant une rugosité. Le coefficient de frottement a été systématiquement calculé et comparé aux résultats issus de la littérature et le torseur fluide sur chaque particule solide des parois a été aussi évalué. Enfin, le couplage partitionné entre les deux codes fluide et solide a été construit et validé qualitativement pour le problème de la sédimentation sous gravité d'un grain solide rigide dans un fluide visqueux.

Integreringsprocessen för utländska barn i den svenska skolan är huvudpunkten i denna systematiska litteraturstudie. Syftet är att undersöka vilka problem som vanligtvis uppkommer i skolan för nyanlända barn med utländsk bakgrund men även deras och föräldrarnas egna önskningar om förbättring eller tillvägagångssätt i integrationsprocessen. Utöver detta analyseras hur skolan arbetar för att integrera eleverna i skolan och in i den ordinarie undervisningen. Resultaten visar att det är många problem som uppstår men de mest återkommande är språket, utanförskap samt ständiga omflyttningar. Vidare visar resultaten att det optimala tillvägagångssättet för en sund integrering i skolan är när eleverna kan knyta an till något och känna samhörighet genom att skolan värnar om deras språk, kultur och familj. Lärarens betydelse för integreringen av de utländska eleverna är även en viktig faktor. Det teoretiska perspektivet som studien grundar sig på är det interkulturella perspektivet.

El objetivo general del trabajo es evaluar el comportamiento del modelo de elevaciones SRTM 90m DEM (Modelo Digital de Elevaciones de la Misión Topográfica de Radar del Transbordador) sobre una zona extendida y de topografía muy variada de la República Argentina e incorporar información local al mismo. La técnica de interferometría de radar se ha analizado y utilizado para explicar el comportamiento del modelo en algunos puntos singulares de la zona de aplicación de esta tesis. La zona de trabajo incluyó parte de las provincias de Buenos Aires, La Pampa, Mendoza, Río Negro y Neuquén. Como información de referencia terrestre, se utilizaron puntos pertenecientes a la Red altimétrica del IGN y a la Red POSGAR07. En particular la Red GEOBA98 y su densificación, con puntos altimétricos GPS sobre todo el territorio de la provincia de Buenos Aires, representó la información de referencia que permitió: generar el DEM mejorado, mediante la integración de sus puntos, y la evaluación de su precisión externa. El DEM mejorado (HSRTM DEMMEJ) obtenido en este trabajo, para la zona de estudio, representa un avance con respecto al modelo original SRTM 90m DEM v4.1 CGIAR-CSI. El modelo gravitacional terrestre EGM96 asociado al SRTM 90 m fue analizado y utilizado como indicador del comportamiento de las alturas elipsoidales del geoide en la zona de estudio. Este análisis permitió expresar el nuevo DEM mejorado en coordenadas elipsoidales para facilitar su aplicación en relación a las determinaciones GNSS e independizarlo del modelo geopotencial utilizado. Los nuevos modelos geopotenciales, como el EGM2008, han significado una sensible mejora en la representación del geoide en gran parte de nuestro país. Por ello, finalmente se obtiene un modelo de elevaciones cuyas alturas se encuentran referidas al modelo gravitacional terrestre EGM2008 (HSRTM Nuevo). Las mejoras obtenidas son estimadas poniendo en consideración las características topográficas de las regiones estudiadas. Este nuevo modelo proporciona precisiones de una decena de centímetros

Depuis ces dernières décennies, peu de sujets de la géologie de l’ingénieur ont attiré autant l’attention de la communauté scientifique que ceux traitant des risques naturels et plus particulièrement des instabilités gravitaires de grandes ampleurs reconnues sous les termes de DSGSD (Deep Seated Gravitational Slope Deformation) et de DSL (Deep Seated Landslide). Basée sur un nombre limité de cas d’étude à l’échelle naturelle (couplage datation et surveillance récente), la dynamique temporelle à court terme reste l’un de leurs aspects les moins étudiés aujourd’hui. Nous avons choisi l’exemple du massif de la Cristallère, situé en haute Vallée d’Aspe dans les Pyrénées béarnaises, où le DSL de la Cristallère a été récemment identifié et analysé à partir de deux méthodes de datation.Dans la continuité de ce travail, notre première approche consiste à évaluer la dynamique temporelle à court terme des mouvements de ce versant à différentes échelles et à partir de différentes méthodes de positionnement par satellites (constellations GPS et GLONASS) : positionnement multistations RGP (Réseau Géodésique Permanent), statique géodésique avec pivot et statique rapide avec pivot. Nous insistons dans ce travail, compte tenu des résultats originaux obtenus, sur l’intérêt du différentiel GNSS (Global Navigation Satellite System) avec un pivot qui se doit d’être proche géographiquement des observations à mener afin d’assurer une précision suffisante (de l’ordre du cm).Les observations et l'exploitation des modèles numériques de terrain issues des relevés aériens à différentes échelles obtenus avec un drone du type « aile volante » constituent la deuxième approche de ce travail de recherche. Elles viennent compléter la cartographie du site et démontrer l’existence d’un DSGSD à partir d’une caractérisation géomorphométrique haute résolution et haute précision (de l’ordre du cm également) ; elles permettent d’affiner la délimitation du DSL de la Cristallère et de sa zone la plus active (Pène du Thès) et du DSL du Peilhou.À ces deux approches complémentaires (combinaison de données tridimensionnelles ponctuelles et surfaciques), s’ajoutent préalablement un relevé de terrain géologique etgéophysique (mesures structurales, tomographies de résistivités électriques et profils électromagnétiques Very Low Frequency) ainsi qu’une analyse des archives disponibles sur les ouvrages présents dans le versant instable, tels que la galerie drainante de la centrale hydroélectrique du Baralet et l’ancien tunnel ferroviaire du Peilhou.L’utilisation combinée de ces trois approches confirme que les mouvements profonds du massif de la Cristallère sont encore actifs avec un forçage sismique avéré : la prise de conscience du rôle que peut jouer le DSGSD est tout aussi fondamentale. Ainsi tous les ouvrages existants dans le massif, ou les projets d’aménagement ou de réhabilitation sur ce site doivent considérer l’existence d’une déstructuration, lente et progressive de l’ensemble du massif (DSGSD). Par ailleurs, la méthodologie développée dans ce travail se veut générale et peut être utilisée pour surveiller et suivre, à court et moyen terme, tous types de mouvement de terrain, et en particulier les glissements de terrain ou rocheux, profonds ou superficiels, lents ou rapides. / For these last decades, few subjects of the geology of the engineer have drawn the attention of the scientific community as much as those dealing of the natural hazards and more particularly with large-scale gravitational instabilities known as DSGSD (Deep Seated Gravitational Slope Deformation) and DSL (Deep Seated Landslide). Based on few cases study on a natural scale (dating and recent monitoring), short term temporal dynamics remains one of their least studied aspects today. We made the choice of the Cristallère massif as an example. It is located in Upper Aspe Valley of the Pyrenees (Béarn region). The Cristallère DSL was recently identified and analyzed through two dating methods.On the basis of this work, our first approach consists in assessing short term temporal dynamics of these slopes movements on various scales and with various methods of satellites positioning (GPS and GLONASS constellations): multistation positioning RGP (Permanent Geodetic Network in France), statics geodetic with pivot and fast static with pivot. We insist in this work, given the original results obtained, on the interest of the differential GNSS (Global Navigation Satellite System) with a pivot which must be geographically close to the observations to be carried out in order to ensure sufficient accuracy (cm).Observations and exploitation of drone digital elevation models of the site from aerial surveys at different scales obtained with a “flying wing” are the second approach to this research work. They complete the mapping of the site and demonstrate the existence of a DSGSD based on a high resolution and high precision geomorphometric characterization (cm); they make it possible to refine the delimitation of the Cristallère DSL and its most active area (Pène du Thès) and the Peilhou DSL.In addition to these two complementary approaches, a geological and geophysical survey (structural geology measurements, electrical resistivity tomographies and electromagnetic profiles Very Low Frequency surveys) and an analysis of the available data on the structures present in the unstable slope, such as the large diameter underground water pipe for the hydroelectric plant of Baralet and the former railway tunnel of Peilhou. The combined use of these three approaches confirms that the deep movements of the Cristallère massif are still active with proven seismic forcing: awareness of the potential role taken by the DSGSD is then fundamental. Thus, all the existing structures in the massif or the projects on this site (new constructions or rehabilitation of old structures) have to consider the existence of a slow and gradual change of the entire massif (DSGSD). Moreover, the methodology developed in this work is intended to be general. It also makes possible to monitor and follow, in the short and medium term, all types of ground movement, in particular landslides or rockslides, deep or superficial, slow or fast.

Made available in DSpace on 2014-12-17T14:09:18Z (GMT). No. of bitstreams: 1 AndreLSS_TESE.pdf: 5521921 bytes, checksum: f9408bc166edc779a453c6cc730acf4f (MD5) Previous issue date: 2014-04-04 / The objective of this Doctoral Thesis was monitoring, in trimestral scale, the coastal morphology of the Northeastern coast sections of Rio Grande do Norte State, in Brazil, which is an area of Potiguar Basin influenced by the oil industry activities. The studied sections compose coastal areas with intense sedimentary erosion and high environmental sensitivity to the oil spill. In order to achieve the general objective of this study, the work has been systematized in four steps. The first one refers to the evaluation of the geomorphological data acquisition methodologies used on Digital Elevation Model (DEM) of sandy beaches. The data has been obtained from Soledade beach, located on the Northeastern coast of Rio Grande Norte. The second step has been centered on the increasing of the reference geodetic infrastructure to accomplish the geodetic survey of the studied area by implanting a station in Corta Cachorro Barrier Island and by conducting monitoring geodetic surveys to understand the beach system based on the Coastline (CL) and on DEM multitemporal analysis. The third phase has been related to the usage of the methodology developed by Santos; Amaro (2011) and Santos et al. (2012) for the surveying, processing, representation, integration and analysis of Coastlines from sandy coast, which have been obtained through geodetic techniques of positioning, morphological change analysis and sediment transport. The fourth stage represents the innovation of surveys in coastal environment by using the Terrestrial Laser Scanning (TLS), based on Light Detection and Ranging (LiDAR), to evaluate a highly eroded section on Soledade beach where the oil industry structures are located. The evaluation has been achieved through high-precision DEM and accuracy during the modeling of the coast morphology changes. The result analysis of the integrated study about the spatial and temporal interrelations of the intense coastal processes in areas of building cycles and destruction of beaches has allowed identifying the causes and consequences of the intense coastal erosion in exposed beach sections and in barrier islands / O objetivo da Tese de Doutorado foi o monitoramento da morfologia costeira em escala trimestral de trechos do Litoral Setentrional do Estado do Rio Grande do Norte, ?rea da Bacia Potiguar sob a influ?ncia das atividades petrol?feras. Trata-se de setores costeiros marcados por intensa eros?o sedimentar e de alta sensibilidade ambiental ao derramamento de ?leo. Para atingir o objetivo geral deste estudo, o trabalho foi sistematizado em quatro etapas. A primeira etapa apresenta a avalia??o das metodologias de aquisi??o de dados geomorfol?gicos utilizada na modelagem digital de eleva??o de praias arenosas a partir de dados obtidos na praia de Soledade, localizada no Litoral Setentrional do Rio Grande do Norte. A segunda etapa foi a amplia??o da infraestrutura geod?sica de refer?ncia para a realiza??o dos levantamentos geod?sicos da ?rea de estudo atrav?s da implanta??o de uma esta??o na ilha barreira de Corta Cachorro e de levantamentos geod?sicos de monitoramento para o entendimento do sistema praial com uso de an?lises multitemporal de LC e MDE. A terceira etapa consistiu na utiliza??o da metodologia geod?sica para o levantamento, processamento, representa??o, integra??o e an?lises de Linhas de Costa (LC) de litorais arenosos obtidos por t?cnicas geod?sicas de posicionamento, an?lise das altera??es morfol?gicas e transporte de sedimentos A quarta etapa foi definida pela inova??o de levantamentos em ambientes costeiros com a utiliza??o do Laser Esc?ner Terrestre (LiDAR) para avalia??o de um trecho submetido a intensa eros?o na praia de Soledade onde est?o instaladas infraestruturas da ind?stria petrol?fera, por meio de MDE de alta precis?o e acur?cia no modelamento das modifica??es na morfologia costeira. As an?lises dos resultados do estudo integrado das interrela??es espaciais e temporais dos intensos processos costeiros atuantes na ?rea ao longo de ciclos de constru??o e destrui??o das praias permitiram identificar as causas e consequ?ncias da intensa eros?o costeira em setores de praias expostas e ilhas barreiras

Made available in DSpace on 2014-12-17T15:03:25Z (GMT). No. of bitstreams: 1 JoseEM_DISSERT_1-90.pdf: 4896611 bytes, checksum: 9ac9fa14f37adc67a0417c2b8781cf4e (MD5) Previous issue date: 2010-12-28 / Digital Elevation Models (DEM) are numerical representations of a portion of the earth surface. Among several factors which affect the quality of a DEM, it should be emphasized the attention on the input data and the choice of the interpolating algorithm. On the other hand, several numerical models are used nowadays to characterize nearshore hydrodynamics and morphological changes in coastal areas, whose validation is based on field data collection. Independent on the complexity of the physical processes which are modeled, little attention has been given to the intrinsic bathymetric interpolation built within the numerical models of the specific application. Therefore, this study aims to investigate and to quantify the influence of the bathymetry, as obtained by a DEM, on the hydrodynamic circulation model at a coastal stretch, off the coast of the State of Rio Grande do Norte, Northeast Brazil. This coastal region is characterized by strong hydrodynamic and littoral processes, resulting in a very dynamic morphology with shallow coastal bathymetry. Important economic activities, such as oil exploitation and production, fisheries, salt ponds, shrimp farms and tourism, also bring impacts upon the local ecosystems and influence themselves the local hydrodynamics. This fact makes the region one of the most important for the development of the State, but also enhances the possibility of serious environmental accidents. As a hydrodynamic model, SisBaHiA? - Environmental Hydrodynamics System ( Sistema B?sico de Hidrodin?mica Ambiental ) was chosen, for it has been successfully employed at several locations along the Brazilian coast. This model was developed at the Coastal and Oceanographical Engineering Group of the Ocean Engineering Program at the Federal University of Rio de Janeiro. Several interpolating methods were tested for the construction of the DEM, namely Natural Neighbor, Kriging, Triangulation with Linear Interpolation, Inverse Distance to a Power, Nearest Neighbor, and Minimum Curvature, all implemented within the software Surfer?. The bathymetry which was used as reference for the DEM was obtained from nautical charts provided by the Brazilian Hydrographic Service of the Brazilian Navy and from a field survey conducted in 2005. Changes in flow velocity and free surface elevation were evaluated under three aspects: a spatial vision along three profiles perpendicular to the coast and one profile longitudinal to the coast as shown; a temporal vision from three central nodes of the grid during 30 days; a hodograph analysis of components of speed in U and V, by different tidal cycles. Small, but negligible, variations in sea surface elevation were identified. However, the differences in flow and direction of velocities were significant, depending on the DEM / Os modelos digitais de terreno (MDT) consistem na representa??o matem?tica computacional da distribui??o de um fen?meno espacial que ocorre dentro de uma regi?o da superf?cie terrestre. A qualidade da representa??o do MDT est? influenciada, dentre outros fatores, pela origem do dado e pelo algoritmo interpolador utilizado. A caracteriza??o da circula??o hidrodin?mica ? um dos estudos com apelo ambiental que se utiliza dos MDTs como dado de entrada e, independentemente da complexidade dos processos representados nos modelos num?ricos, pode ter a qualidade de seus resultados dependente da capacidade de reprodu??o do MDT usado para representar a batimetria da ?rea de interesse. Sendo assim, o objetivo deste estudo ? avaliar a influ?ncia de batimetrias obtidas de diversos MDTs, nos padr?es de circula??o hidrodin?mica via modelagem num?rica. Para tanto, considerou-se os dados referentes ? regi?o costeira do nordeste do Brasil, correspondente ao litoral setentrional do estado do Rio Grande do Norte, frontal aos munic?pios de Macau, Guamar? e Galinhos. Essa regi?o se caracteriza pela forte presen?a de processos f?sicos costeiros, com batimetria rasa e complexas fei??es de fundo. A presen?a intensa de atividades petrol?feras faz da regi?o uma das mais importantes para o desenvolvimento socioecon?mico do estado, mas, por outro lado, potencializa a possibilidade de acidentes ambientais de grandes e graves propor??es. O modelo de circula??o hidrodin?mica utilizado foi o 2DH, que faz parte do Sistema de Hidrodin?mica Ambiental, chamado SisBaHiA?, desenvolvido pela ?rea de Engenharia Costeira e Oceanogr?fica do Programa de Engenharia Oce?nica da COPPE/UFRJ. Os interpoladores avaliados foram Vizinho Natural, Krigagem, Triangula??o Irregular Linear, Inverso da Dist?ncia, Vizinho mais Pr?ximo, M?nima Curvatura, Fun??o de Base Radial, Polin?mio Local, Regress?o Polinomial, M?dia M?vel, M?trica de Dados e M?todo de Shepard Modificado, implementados no software comercial Surfer? para a gera??o dos MDTs. Os dados batim?tricos, que serviram como base para a constru??o dos MDTs, s?o oriundos de campanha de campo e de cartas n?uticas. Os resultados das modelagens foram analisados pelas avalia??es dos campos de velocidade e eleva??o, sob tr?s aspectos: uma vis?o espacial dos resultados, atrav?s da an?lise de tr?s perfis perpendiculares ? linha de costa e um perfil transversal ? linha de costa; uma vis?o temporal dos resultados, ao longo do per?odo de 30 dias, a partir de tr?s n?s centrais da malha; e finalmente uma an?lise hodogr?fica das componentes de velocidade em U e V, em diferentes ciclos de mar?s. Foram verificadas varia??es pouco significativas nos campos de eleva??es, podendo as mesmas serem desprezadas, por?m no que diz respeito aos campos de velocidade e dire??es de fluxo, notam-se varia??es associadas aos MDTs utilizados, uma vez que todas as condicionantes hidrodin?micas foram mantidas