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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
521

Etude multi-scalaire de la dynamique latérale des tronçons fluviaux- Application au bassin rhodanien / Multi-scale study of the lateral dynamic of fluvial reaches.- Application to the Rhône basin.

Alber, Adrien 18 December 2012 (has links)
La migration latérale est reconnue comme un processus majeur à préserver pour le bon fonctionnement des écosystèmes aquatiques. Ce travail explore sa variabilité spatiale dans le Sud-Est de la France en appui à la mise en œuvre de la Directive Cadre sur l’Eau.Une première partie développe un cadre méthodologique et des outils géomatiques pour la caractérisation géomorphologique et l’analyse multi-scalaire des systèmes fluviaux à partir de données disponibles à large échelle. Un premier article présente la démarche générale basée sur l’agrégation et la désagrégation spatiale d’objets vectoriels. Un second article aborde spécifiquement le problème de l’agrégation spatiale et vise à comparer des techniques statistiques pour la sectorisation d’un continuum en tronçons homogènes. Des exemples illustrent l’intérêt et les limites des outils développés.Une seconde partie porte sur la régionalisation de la dynamique latérale des lits fluviaux. Un troisième article caractérise et modélise son intensité à partir de variables simples à extraire à l'échelle régionale. Il montre qu’elle est structurée spatialement et positivement corrélée à la puissance fluviale. Néanmoins, des limites inhérentes à la modélisation empirique et la nécessaire prise en compte de variables complémentaires à l’échelle régionale émergent (apport sédimentaire notamment). Un quatrième article porte spécifiquement sur les lits à tresses et montre que près de la moitié des 1200 kilomètres recensés avant la construction des grandes infrastructures ont disparu du fait de pressions anthropiques directes et indirectes. Il révèle par ailleurs la grande diversité géomorphologique de ce style fluvial dans le bassin rhodanien. / The channel migration is a key process for preserving the aquatic ecosystem functioning. This work explores its spatial variability throughout the South-East French hydrographic network for the implementation of the European Water Framework Directive.A first part develops a methodological framework and geomatic tools for the characterization and analysis of the fluvial systems for a range of scales from spatially continuous data available at the large scale. A first paper introduces the methodological framework based on the spatial disaggregation and aggregation of geographical objects. A second paper focuses specifically on the aggregating problem and aims to compare statistical techniques for delineating homogeneous reaches along a continuum. Examples illustrate the potentialities and limits of the tools we developed. A second part focuses on the regionalization of the channel migration. A third paper characterizes and models the migration rates from simple variables that can be extracted at the large scale. We show that the migration rate is spatially organized and positively controlled by the gross stream power. Nevertheless, limits of the regional-scale empirical modeling emerge, as well as additional variables that should be integrated (particularly the sediment supply). A fourth paper focuses specifically on braided rivers and shows that near the half of the 1200 kilometers censed prior to the major infrastructure construction disappeared due to direct and indirect human impacts. It also reveals the high geomorphic diversity of the contemporary braided rivers in the Rhône basin.
522

Analyzing Spatial Patterns in Reefscape Ecology Via Remote Sensing, Benthic Habitat Mapping, and Morphometrics

Dunn, Shanna K. 04 December 2009 (has links)
A growing number of scientists are investigating applications of landscape ecology principles to marine studies, yet few coral reef scientists have examined spatial patterns across entire reefscapes with a holistic ecosystem-based view. This study was an effort to better understand reefscape ecology by quantitatively assessing spatial structures and habitat arrangements using remote sensing and geographic information systems (GIS). Quantifying recurring patterns in reef systems has implications for improving the efficiency of mapping efforts and lowering costs associated with collecting field data and acquiring satellite imagery. If a representative example of a reef is mapped with high accuracy, the data derived from habitat configurations could be extrapolated over a larger region to aid management decisions and focus conservation efforts. The aim of this project was to measure repeating spatial patterns at multiple scales (10s m2 to 10s km2) and to explain the environmental mechanisms which have formed the observed patterns. Because power laws have been recognized in size-frequency distributions of reef habitat patches, this study further investigated whether the property exists for expansive reefs with diverse geologic histories. Intra- and inter-reef patch relationships were studied at three sites: Andavadoaka (Madagascar), Vieques (Puerto Rico), and Saipan (Commonwealth of the Northern Mariana Islands). In situ ecological information, including benthic species composition and abundance, as well as substrate type, was collected with georeferenced video transects. LiDAR (Light Detection and Ranging) surveys were assembled into digital elevation models (DEMs), while vessel-based acoustic surveys were utilized to empirically tune bathymetry models where LiDAR data were unavailable. A GIS for each site was compiled by overlying groundtruth data, classifications, DEMs, and satellite images. Benthic cover classes were then digitized and analyzed based on a suite of metrics (e.g. patch complexity, principle axes ratio, and neighborhood transitions). Results from metric analyses were extremely comparable between sites suggesting that spatial prediction of habitat arrangements is very plausible. Further implications discussed include developing an automated habitat mapping technique and improving conservation planning and delimitation of marine protected areas.
523

Arrangements 2D pour la Cartographie de l’Espace Public et des Transports / 2D Arrangements for Public Space Mapping and Transportation

Yirci, Murat 15 April 2016 (has links)
Cette thèse porte sur le développement facilité d'applications de cartographie et de transport, plus particulièrement sur la génération de réseaux piétonniers pour des applications telles que la navigation, le calcul d'itinéraires, l'analyse d'accessibilité et l'urbanisme. Afin d'atteindre ce but, nous proposons un modèle de données à deux couches qui cartographie l'espace public dans une hiérarchie d'objets géospatiaux sémantisés. A bas niveau, la géométrie 2D des objets géospatiaux est représentée par une partition planaire, modélisée par une structure topologique d'arrangement 2D. Cette représentation permet des traitements géométriques efficaces et efficients, ainsi qu'une maintenance et une validation aisée au fur et à mesure des éditions lorsque la géométrie ou la topologie d'un objet sont modifiées. A haut niveau, les aspects sémantiques et thématiques des objets géospatiaux sont modélisés et gérés. La hiérarchie entre ces objets est maintenue à travers un graphe dirigé acyclique dans lequel les feuilles correspondent à des primitives géométriques de l'arrangement 2D et les noeuds de plus haut niveau représentent les objets géospatiaux sémantiques plus ou moins aggrégés. Nous avons intégré le modèle de données proposé dans un framework SIG nommé StreetMaker en complément d'un ensemble d'algorithmes génériques et de capacités SIG basiques. Ce framework est alors assez riche pour générer automatiquement des graphes de réseau piétonnier. En effet, dans le cadre d'un projet d'analyse d'accessibilité, le flux de traitement proposé a permis de produire avec succès sur deux sites un graphe de réseau piétonnier à partir de données en entrées variées : des cartes vectorielles existantes, des données vectorielles créées semi-automatiquement et des objets vectoriels extraits d'un nuage de points lidar issu d'une acquisition de cartographie mobile.Alors que la modélisation 2D de la surface du sol est suffisante pour les applications SIG 2D, les applications SIG 3D nécessitent des modèles 3D de l'environnement. La modélisation 3D est un sujet très large mais, dans un premier pas vers cette modélisation 3D, nous nous sommes concentrés sur la modélisation semi-automatique d'objets de type cylindre généralisé (tels que les poteaux, les lampadaires, les troncs d'arbre, etc) à partir d'une seule image. Les méthodes et techniques développées sont présentées et discutées / This thesis addresses easy and effective development of mapping and transportation applications which especially focuses on the generation of pedestrian networks for applications like navigation, itinerary calculation, accessibility analysis and urban planning. In order to achieve this goal, we proposed a two layered data model which encodes the public space into a hierarchy of semantic geospatial objects. At the lower level, the 2D geometry of the geospatial objects are captured using a planar partition which is represented as a topological 2D arrangement. This representation of a planar partition allows efficient and effective geometry processing and easy maintenance and validation throughout the editions when the geometry or topology of an object is modified. At the upper layer, the semantic and thematic aspects of geospatial objects are modelled and managed. The hierarchy between these objects is maintained using a directed acyclic graph (DAG) in which the leaf nodes correspond to the geometric primitives of the 2D arrangement and the higher level nodes represent the aggregated semantic geospatial objects at different levels. We integrated the proposed data model into our GIS framework called StreetMaker together with a set of generic algorithms and basic GIS capabilities. This framework is then rich enough to generate pedestrian network graphs automatically. In fact, within an accessibility analysis project, the full proposed pipeline was successfully used on two sites to produce pedestrian network graphs from various types of input data: existing GIS vector maps, semi-automatically created vector data and vector objects extracted from Mobile Mapping lidar point clouds.While modelling 2D ground surfaces may be sufficient for 2D GIS applications, 3D GIS applications require 3D models of the environment. 3D modelling is a very broad topic but as a first step to such 3D models, we focused on the semi-automatic modelling of objects which can be modelled or approximated by generalized cylinders (such as poles, lampposts, tree trunks, etc.) from single images. The developed methods and techniques are presented and discussed
524

Propuesta de automatización del proceso de distribución en una empresa ecológica mediante soluciónes tecnológicas web y móvil / Automation proposal of the distribution process in an ecological company through web and mobile technological solutions

Orihuela Meza, Jhon Albert, Morales Perez, Victor Hugo 19 August 2021 (has links)
El uso de tecnologías de información para planificar actividades y monitorear a través de la posición geográfica ya sean durante la distribución, delivery o geolocalización de pedidos ha tomado bastante importancia en la actualidad. Por consecuente, el presento proyecto propone una automatización del proceso de distribución mediante soluciones tecnológicas web y móvil GIS, a partir del análisis de las actividades que se realizan en dicho proceso. Esta propuesta, tiene como objetivo reducir las tareas manuales que se realizan en dicho proceso, así mismo, habilitar un medio de monitoreo en tiempo real de los repartidores y pedidos de los clientes. Para lograr la propuesta se realiza una conceptualización y análisis de la empresa empleando los marcos de trabajo de Zachman en el nivel 1 y 2 y TOGAF, de esta manera se identifica la situación problemática, los objetivos del proyecto e indicadores de éxito. Esta información fue la base para diagramar los procesos actuales y los mejorados con el uso BPMN. Luego, para diseñar las soluciones tecnológicas se empleó la ingeniera de requerimientos para que finalmente se plasme ese análisis en diagramas de arquitectura en cuatro niveles usando como guía el modelo C4. Finalmente, se hace uso de la guía de PMBOK para la gestión del proyecto que como resultado permitió planificar las actividades, estimar los tiempos de ejecución y los costos que conllevan la implementación de la propuesta de automatización. / The use of information technologies to plan activities and monitor through the geographical position, whether during the distribution, delivery or geolocation of orders has become quite important today. Consequently, the present project proposes an automation of the distribution process through web and mobile GIS technology solutions, based on the analysis of the activities carried out in said process. The objective of this proposal is to reduce the manual tasks that are carried out in this process, as well as to enable a means of real-time monitoring of the distributors and customer orders. To achieve the proposal, a conceptualization and analysis of the company is carried out using the Zachman frameworks at level 1 and 2 and TOGAF, in this way the problematic situation, the project objectives and indicators of success are identified. This information was the basis for diagramming the current processes and those improved with the use of BPMN. Then, to design the technological solutions, requirements engineering was used to finally translate that analysis into four-level architecture diagrams using the C4 model as a guide. Finally, the PMBOK guide is used to manage the project, which as a result allowed to plan the activities, estimate the execution times and the costs involved in the implementation of the automation proposal. / Tesis
525

Návrh územního plánu pro obec Radešín / Design of district structure plan Radešín

Moučka, Michal January 2020 (has links)
Town and country planning is an activity which is trying to find and create the most suitable conditions for the use and spatial arrangement of the territory based on comprehensive knowledge of various disciplines and therefore we rank it among multidisciplinary disciplines. The result of efforts is to ensure the sustainable development of the territory which is frequently highlighted in connection with town and country planning. The diploma thesis solves the issue of town and country planning from the point of view of the Act on town and country planning and building code with focusing on its tools. One of the tools of town and country planning is the subject of the main part of the diploma thesis which deals with the specific design of the local zoning plan of the village Radešín.
526

Studie návrhu přírodě blízkých protierozních a protipovodňových opatření v povodí Jičínky / The design study of biotechnical erosion and flood control measures in the catchment of Jičínka river

Škrabal, Tomáš January 2013 (has links)
The main subject of this diploma thesis is a study of a suggestion of environmentally friendly adjustments in the basin of Jičínka, working as preventive protection against floods. The study contains a research of the stated area using the method of CN-curves in the hydrological model DesQ-MaxQ and the principle of Wischmeier-Smith's equation, in modicication of ArcGIS programme. Based on the analysis, the work suggests an improvement of erosive and drain ratios and then an assessment of effectiveness of the protection. We get the assessment of the effectiveness by comparing the condition of the erosive wash and the surface drain before and after implementation of our measures. The work also sets its goal in calculating the financial returnability of the investition indicatively.
527

GIS využití krajiny obce Jinačovice / Land use GIS of Jinačovice municipality

Kelblová, Kristýna January 2013 (has links)
This master thesis focuses on the development of the GIS in the Jinačovice municipality, particularly on the land use. The core data used for the research has been gathered by aerial photography since 1950. Other data sources include other types of maps, especially Cadastral map, ZABAGED data and statistical data. An analysis of the Land use has been carried out as well as additional analyses of the area. The research has been conducted specifically for the Jinačovice municipality.
528

Modelling landfill site suitability in Gauteng Province using GIS

Tshimange, Tshilidzi 11 February 2016 (has links)
Department of Ecology and Resource Management / MENVM
529

Neue Analyse- und Visualisierungsmöglichkeiten im Monitor der Siedlungs- und Freiraumentwicklung (IÖR-Monitor)

Förster, Jochen 02 March 2015 (has links)
Der Monitor der Siedlungs- und Freiraumentwicklung, kurz: „IÖR-Monitor“ informiert seit 2010 im Internet über die Entwicklung der Siedlungs- und Freiraumstruktur in Deutschland. Dabei befindet er sich in stetiger Weiterentwicklung, sowohl was das Indikatorenset betrifft, als auch die Visualisierungs- und die Analysemöglichkeiten. Der Beitrag beschreibt die neuesten Entwicklungen des Übersichts-Viewers und gibt einen Einblick in den entstehenden Detail-Viewer.
530

Zur Erzeugung hochauflösender datenschutzkonformer Mischrasterkarten

Dießelmann, Markus, Meinel, Gotthard January 2013 (has links)
Die zunehmende Verfügbarkeit adressbezogener Daten im Zusammenhang mit der Nutzung geometrischer Raster zur Raumuntergliederung haben die Voraussetzungen für kleinräumige Analysen deutlich verbessert. Bei der Verwendung personenbezogener Daten müssen datenschutzrechtliche Vorgaben eingehalten werden, falls die Rasterzellen zu wenig Fallzahlen enthalten. Vielfach werden diese Rasterzellen ausgeblendet, wodurch Informationen in der Karte verloren gehen. Eine datenschutzkonforme Alternative stellt die Aggregation von Rasterzellen dar, bis die Fallzahlen einen vorgegebenen Grenzwert überschreiten. In diesem Beitrag werden Möglichkeiten vorgestellt und bewertet, nach denen sich datenschutzkonforme Mischrasterkarten erzeugen lassen. Besonderes Augenmerk wird auf die Auflösungsverluste der erzeugten Mischrasterkarten gelegt, um geeignete Datengrundlagen für kleinräumige Analysen zu schaffen.

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