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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.
71

Urban Growth Modeling Based on Land-use Changes and Road Network Expansion

Rui, Yikang January 2013 (has links)
A city is considered as a complex system. It consists of numerous interactivesub-systems and is affected by diverse factors including governmental landpolicies, population growth, transportation infrastructure, and market behavior.Land use and transportation systems are considered as the two most importantsubsystems determining urban form and structure in the long term. Meanwhile,urban growth is one of the most important topics in urban studies, and its maindriving forces are population growth and transportation development. Modelingand simulation are believed to be powerful tools to explore the mechanisms ofurban evolution and provide planning support in growth management. The overall objective of the thesis is to analyze and model urban growth basedon the simulation of land-use changes and the modeling of road networkexpansion. Since most previous urban growth models apply fixed transportnetworks, the evolution of road networks was particularly modeled. Besides,urban growth modeling is an interdisciplinary field, so this thesis made bigefforts to integrate knowledge and methods from other scientific and technicalareas to advance geographical information science, especially the aspects ofnetwork analysis and modeling. A multi-agent system was applied to model urban growth in Toronto whenpopulation growth is considered as being the main driving factor of urbangrowth. Agents were adopted to simulate different types of interactiveindividuals who promote urban expansion. The multi-agent model with spatiotemporalallocation criterions was shown effectiveness in simulation. Then, anurban growth model for long-term simulation was developed by integratingland-use development with procedural road network modeling. The dynamicidealized traffic flow estimated by the space syntax metric was not only used forselecting major roads, but also for calculating accessibility in land-usesimulation. The model was applied in the city centre of Stockholm andconfirmed the reciprocal influence between land use and street network duringthe long-term growth. To further study network growth modeling, a novel weighted network model,involving nonlinear growth and neighboring connections, was built from theperspective of promising complex networks. Both mathematical analysis andnumerical simulation were examined in the evolution process, and the effects ofneighboring connections were particular investigated to study the preferentialattachment mechanisms in the evolution. Since road network is a weightedplanar graph, the growth model for urban street networks was subsequentlymodeled. It succeeded in reproducing diverse patterns and each pattern wasexamined by a series of measures. The similarity between the properties of derived patterns and empirical studies implies that there is a universal growthmechanism in the evolution of urban morphology. To better understand the complicated relationship between land use and roadnetwork, centrality indices from different aspects were fully analyzed in a casestudy over Stockholm. The correlation coefficients between different land-usetypes and road network centralities suggest that various centrality indices,reflecting human activities in different ways, can capture land development andconsequently influence urban structure. The strength of this thesis lies in its interdisciplinary approaches to analyze andmodel urban growth. The integration of ‘bottom-up’ land-use simulation androad network growth model in urban growth simulation is the major contribution.The road network growth model in terms of complex network science is anothercontribution to advance spatial network modeling within the field of GIScience.The works in this thesis vary from a novel theoretical weighted network modelto the particular models of land use, urban street network and hybrid urbangrowth, and to the specific applications and statistical analysis in real cases.These models help to improve our understanding of urban growth phenomenaand urban morphological evolution through long-term simulations. Thesimulation results can further support urban planning and growth management.The study of hybrid models integrating methods and techniques frommultidisciplinary fields has attracted a lot attention and still needs constantefforts in near future. / <p>QC 20130514</p>
72

Modeling of complex network, application to road and cultural networks

Jiang, Jian 12 September 2011 (has links) (PDF)
Many complex systems arising from nature and human society can be described as complex networks. In this dissertation, on the basis of complex network theory, we pay attention to the topological structure of complex network and the dynamics on it. We established models to investigate the influences of the structure on the dynamics of networks and to shed light on some peculiar properties of complex systems. This dissertation includes four parts. In the first part, the empirical properties (degree distribution, clustering coefficient, diameter, and characteristic path length) of urban road network of Le Mans city in France are studied. The degree distribution shows a double power-law which we studied in detail. In the second part, we propose two models to investigate the possible mechanisms leading to the deviation from simple power law. In the first model, probabilistic addition of nodes and links, and rewiring of links are considered; in the second one, only random and preferential link growth is included. The simulation results of the modelling are compared with the real data. In the third part,the probabilistic uncertainty behavior of double power law distribution is investigated. The network optimization and optimal design of scale free network to random failures are discussed from the viewpoint of entropy maximization. We defined equilibrium network ensemble as stationary ensembles of graphs by using some thermodynamics like notions such as "energy", "temperature", "free energy" for network. In the forth part, an union-division model is established to investigate the time evolution of certain networks like cultural or economical networks. In this model, the nodes represent, for example, the cultures. Several quantities such as richness, age, identity, ingredient etc. are used to parameterize the probabilistic evolution of the network. The model offers a long term view on the apparently periodic dynamics of an ensemble of cultural or economic entities in interaction.
73

Analýza krajinných změn vlivem komplexní pozemkové úpravy / The analysis of landscape changes the influence comprehensive landscaping

ŠIMÁKOVÁ, Iveta January 2016 (has links)
The purpose of this study was to analyse and asses the landscape changes on selected cadastral areas with completed comprehensive landscaping. For this purpose, two appropriate cadastral territory were selected, the cadastral area Borkovice and the cadastral area Myslkovice. The analysis was performed at three time periods - before the project the landscaping, in the project of landscaping and in the current state of the landscape. The changes in the landscape were assessed according to the state land use, road networks and territorial system of ecological stability. The results were processed into individual tables and graphs, providing information on the status of proposed and actually implemented elements.
74

Zpracování plánu společných zařízení v komplexní pozemkové úpravě ve zvolené lokalitě / Processing of common facilities plan in the complex land consolidation in selected area

ŠVECOVÁ, Markéta January 2017 (has links)
The subject of this thesis is to elaborate plan of common facilities in the complex land adjustment in the selected location. The plan of common facilities includes a set of measures which are designed to create the conditions for rational management, and also ensure the protection of natural resources. Solution site is the village Lhotka. The thesis contains a description and evaluation of the cadastral area, focusing on measures to make available land for erosion control land resources, measures for the creation and protection of the environment and water management measures. The results are contained in text form, as well as graphic, processed through the program ArcGIS.
75

Využití finančních prostředků z fondů EU a veřejných rozpočtů na výstavbu silnic a dálnic v Jihočeském kraji za programové období 2007-2013 / Use of the financial resources from funds of EU and from public budget on development of motorway and road in the South Bohemia Region during programming period 2007-2013

PLEVOVÁ, Tereza January 2018 (has links)
This thesis is focus on evaluation of use of the financial resources from funds of EU and from public budget on development of motorway and road in the South Bohemia Region in programming period 2007-2013. The aim of this work is an answer the question,whether the financial resources from funds of EU were used effectively and how effect had these projects on development of region. The other aims are description of transport projects, analysis of financial resources, evaluation of successful and unsuccesfull projects, description of potential development in programming period 2014-2020. It is a qualitative research. In this thesis is used the secondary analysis of data, comparison, triangulation.
76

Zpracování plánu společných zařízení v komplexní pozemkové úpravě ve zvolené lokalitě / Processing of common facilities plan in the complex land consolidation in selected area

ŠPAČKOVÁ, Hana January 2018 (has links)
This diploma thesis presents a plan proposal for the common facilities in a complex land consolidation carried out in the locality of Loučky u Jihlavy in the Vysočina region. The first, theoretical part is a literature research of land treatment and the plan for common facilities including the scope of exploration work necessary for its preparation. The practical part comprises field work, its assessment and description of the cadastral area. The thesis provides a complete list of information and findings of the fieldwork with focus on measures leading to accessibility of the land parcels, anti-erosion measures, water management measures and measures to ensure climate protection. The findings are listed in both a textual and graphic form.
77

Automatic reconstruction of realistic road networks from GIS data / Reconstruction de réseaux routiers réalistes à partir de données SIG

Nguyễn, Hoàng Hà 18 March 2016 (has links)
La reconstruction de routes est un sujet important dans le domaine de la modélisation 3D. Nous proposons dans cette thèse des méthodes pour construire des modèles de réseaux routiers réalistes à partir de données SIG.Tout d'abord, les problèmes de la reconstruction d'un simple axe de route à partir d'une polyligne sont étudiés. Nous présentons un modèle de courbe par morceaux G1 qui est non seulement fidèle à l'axe de la route réelle mais aussi pratique et pas onéreux à obtenir. Notre algorithme Least Square Growing crée, comme dans le génie civil, une courbe horizontale et une courbe verticale, puis les combine pour produire un axe routier 3D approchant la polyligne. Traiter individuellement des polylignes conduit à des discontinuités aux intersections des routes. C’est pourquoi nous introduisons une procédure pour détecter les relations entre les routes, afin de proposer un processus global pour reconstruire tous les axes routiers avec prenant en compte les nouvelles contraintes sur les extrémités des routes.Enfin, sur la base de l'axe de la route et les propriétés résultant de la route dans la base de données SIG, nous définissons un modèle mathématique de la surface de la route en respectant les contraintes essentielles de surfaces routières réelles. Pour produire une géométrie représentant la surface de la route finale, nous construisons un maillage grossier de la carte d'élévation du terrain d'entrée, que nous subdivisons adaptativement le long de l'axe de la route, puis ajustons l'altitude des sommets concernés à la valeur définie par le modèle mathématique de la route afin de parvenir à une correspondance correcte entre le terrain et la vraie route. / Road reconstruction is an important topic in 3D modeling. Recently, the steady development of many critical-accurate applications has posed a high demand for realistic road models, taking into account road-design constraints selected from civil engineering. We propose in this dissertation methods for building realistic road network models from GIS data.Firstly, problems of single road axis reconstruction from a polyline are addressed. We present a novel G1-piecewise-curve model which is not only faithful to the real road axis but also convenient and cheap to render. Our Least Square Growing Algorithm creates, as in civil engineering, an horizontal and a vertical curves, then combines them to produce a 3D road axis fitting well the polyline. Processing individual polyline will leads to the discontinuities at road intersections so we introduce a procedure to detect road relations, then we propose a global process to reconstruct all road axes with the considerations on further constraints of road ends.Finally, based upon the resulting road axis and road properties in the GIS database, we define a mathematical road surface model respecting the essential constraints of real road surfaces. To produce a geometry representing the final road surface, we build a coarse mesh from the input terrain highmap, subdivide it adaptively along the road axis, then adjust the altitude of concerning vertices to the value defined by the mathematical model in order to attain a correct mapping between the terrain and the real road.
78

Extraction des informations sur la morphologie des milieux urbains par analyse des images satellites radars interférométriques

Aubrun, Michelle 12 1900 (has links)
No description available.
79

Modélisation à base d'agents de l'évacuation automobile dans un contexte d'accident technologique. Application à la ville de Rouen / Agent-based modeling of massive evacuation in a context of technological hazard. A case study of Rouen, France

Czura, Guillaume 20 November 2017 (has links)
En France, dans un contexte d’accident technologique, les consignes de mise en sécurité de la population préconisent le confinement à défaut de l’évacuation, pour laquelle les retours d’expérience à l’échelle d’une ville sont rares. De plus, s’il existe de nombreux documents de gestion du risque et de crise, ces derniers n’intègrent que de manière très marginale la population automobile, pour laquelle l’évacuation demeure pourtant la solution la plus adaptée. Le (bon) déroulement d’un tel processus dépend à la fois de la stratégie mise en place par les autorités publiques (le cas échéant) et des dynamiques de déplacement, rythmées par les choix opérés par chaque automobiliste. En effet, certains comportements individuels peuvent générer des conflits en quelques points du réseau routier et contribuer ainsi à une augmentation du temps nécessaire pour évacuer les automobilistes présents sur l’ensemble du réseau exposé. Ce travail de recherche s’est attaché, par la simulation multi-agents, à développer une méthode capable de rendre compte, dans l’espace et dans le temps, des conséquences que pourraient engendrer telle ou telle stratégie d’évacuation, à Rouen (Normandie). À partir d’une modélisation des déplacements quotidiens, une série de scénarios d’évacuation a été testée, combinant la mise en place ou non d’itinéraires spécifiques, le maintien ou non de la signalétique et l’adoption d’un comportement impatient de conduite par un certain nombre d’automobilistes. L’efficacité de chaque stratégie, définie en termes de durée d’évacuation totale, est complétée par une analyse cartographique et dynamique des zones problématiques (saturées) du réseau rouennais. / In France, when an industrial accident occurs, the population confinement mainly prevails over its evacuation. Moreover, the latter suffers a lack of experience feedbacks, especially at the city scale. In addition, while numerous risk management and crisis documents exist, they marginally integrate the car drivers, for which evacuation does remain the most appropriate solution. The (good) progress of such a process depends both on (1) the public authorities’ strategy and (2) the choices made by each car driver during his trip. Indeed, some individual behaviors can generate conflicts in some points of the road network, and thus increase the duration of the whole network discharge. Thanks to the multi-agents simulation, we developed a method able to report the spatio-temporal consequences generated by different evacuation strategies, in Rouen (Normandy). Based on a daily travel model, a series of evacuation scenarios is tested, combining whether or not specific routes are set up, whether or not signage are maintained, and the adoption of an impatient behavior by some car drivers. The effectiveness of each strategy is defined by the total evacuation duration, and completed by a cartographic and dynamic analysis of the jammed areas of the Rouen network.
80

Estimation et analyse spatiales des émissions de polluants de transports individualisés : évaluation des performances environnementales d'un Transport à la Demande / Spatial estimating and analyse of exhaust emissions from individual transports : Assessment of the environmental performance of a demand responsive transport

Prud'homme, Julie 25 October 2013 (has links)
Le Transport A la Demande (TAD) est un système de transport qui propose un usage collectif des véhicules automobiles, par opposition à l’usage des véhicules personnels (VP). Situé entre le fonctionnement des taxis et celui des transports en commun classiques, il propose un service à la fois flexible dans le temps et dans l'espace à la manière des taxis, favorisant le partage des véhicules, comme les transports en commun. Il est ainsi présenté comme une réponse pour une mobilité durable. Dans les esprits, les TAD sont souvent associés à une réduction des émissions de polluants et sont mis en place principalement dans des territoires ruraux. Pourtant, le simple regroupement effectué par les TAD suffit-il pour que la mise en place des TAD soit profitable à l’environnement ? Dans ce travail de recherche de doctorat, un outil d’évaluation de l'impact environnemental d’un système de Transports À la Demande (TAD) destiné aux collectivités territoriales a été mis au point. Pour que choix soit durable, au sens du développement durable, le service doit être le plus adapté au contexte local en minimisant les émissions de substances dans l’atmosphère proche tout en conservant une qualité de service suffisante pour concurrencer l'usage du véhicule personnel. Un paramètre, directement impliqué dans les émissions de polluant, est souvent négligé dans les approches : le réseau routier. On cherche donc à identifier des lois et des seuils relatifs aux émissions de polluants produites par le fonctionnement d’un TAD : dans quelle mesure le réseau routier influe-t-il sur les performances environnementales des TAD ou sur la capacité de regroupement des clients dans les véhicules ? Selon quelles caractéristiques de service (fenêtres de temps autorisées) ? Plus globalement, est-ce que l’optimisation d’un même type de TAD est équivalente d’un réseau routier à un autre, du point de vue des émissions de polluants ? Aucun outil intégré permettant d’effectuer cette tâche n’étant disponible, nous avons mis au point une chaîne de traitement géomatique permettant d’estimer les quantités de polluants émises sur les tronçons de route dans le cadre du fonctionnement particulier des TAD et de les cartographier pour analyser leur répartition spatiale. Cet outil associe un SIG à un modèle d’émission que nous avons adapté à notre problématique (GREEN-DRT). Il est ressorti des différents scénarios simulés que les TAD ne sont pas systématiquement une solution pertinente dans un objectif de réduction globale des émissions de polluants sur un territoire donné. Le constat de la faible pertinence environnementale de ce mode de transport sur les territoires les moins denses (type zones rurales) a été fait, pourtant, ce sont sur ces territoires que les TAD sont développés en France. À défaut d’engendrer une réduction des émissions, ils ont souvent un rôle social important en se positionnant non pas comme une alternative à la voiture personnelle, mais en permettant à des populations captives de se déplacer. Il s’agit de ce cas de minimiser les émissions de polluants provoquées par le fonctionnement du service. / The Demand Responsive Transport (DRT) is a transportation system which offers a collective use of motor vehicles, in opposite of personal vehicles use. Between the functioning of taxis and classical public transport, it offers a service that is flexible in time and space like taxis, promoting the sharing of vehicles, like public transports. It is why it is present as a solution for a sustainable mobility. In the minds, DRT are often associated to a reduction of exhaust emissions and so are developed in rural areas. However, is grouping travellers enough to make DRT gainful for environment?In this doctoral research, an assessment tool of the environmental impact of DRT systems has been developed. To ensure that choice is sustainable in the sense of sustainable development, the service must be adapted to the local context by minimising emissions of substances in the near atmosphere while maintaining a sufficient quality of service when competing against personal vehicle use. A parameter directly involved in pollutant emissions, is often overlooked in approaches: the road network. We therefore search for identify laws and thresholds relating to pollutant emissions generated by the functioning of a DRT: how the road network does it affect the environmental performance of DRT or on the skill to grouping customers in vehicles? Depending on what service features (time windows allowed)? More generally, is that the optimization of the same type of DRT is equivalent to a road network to another, from the perspective of pollutant emissions? As any integrated tool to perform this task is available, we have developed a geomatics processing to estimate the quantities of pollutants emitted on road sections within the particular functioning of DRT and to cartography it to analyse their spatial distribution. This tool combines a GIS to an exhaust emissions model that we have adapted to our questioning (GREEN-DRT).

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