Digital Earth is a kind of GIS application which use lots of computer techniques, including ¡§Computer Graphic¡¨, ¡§High quality Satellite Image¡¨, ¡§Multi-resolution¡¨, ¡¨ Metadata¡¨, ¡¨Level of detail¡¨, etc. In the past, geographers always tend to use triangle or grid structure to build 3D GIS. Now 3D GIS tend to use VRML to display virtual terrain data. Nevertheless, this display method is short of three-dimension analysis. It just uses 2.5 dimension to simulate 3 dimension space structure. This thesis is base on the theory of GeoVRML Quad-tree structure and use JAVA to implement ROAM algorithm. And this method can improve Quad-tree structure morphing error and raise virtual terrain display speed. This thesis use ETOPO5 5-minute DTM data to build Earth model (provide by NGDC) and Taiwan 40M DTM data, 200M, 100M, 50M, 25M satellite image to build Taiwan 3D GIS model. Meanwhile, this thesis addresses an unique three level structure to display 3D GIS model. One is Satellite Image layer, one is virtual terrain layer, and last one is 3D feature object.

Geographical image data efficiently help people with wayfinding when in an unfamiliar environment. However, since the display modes of geographical image data such as 2D and 3D virtual reality could not meet with users' needs anymore, the new technique augmented reality (AR) has then become a better and effective solution to graphics Augmented reality is a kind of 3D display technique by computer vision, in which 3D virtual objects are combined with 3D real environment interactively, dynamically, and in real-time. It will bring more advantages especially to the display of building spatial data. The research aims to find out more spatial information by seeing-through buildings when we stay outside it. The approach is firstly to use a single camera to capture building features with serial images, and secondly to do building recognition and tracking between reference images and serial images by Speeded-Up Robust Features (SURF) algorithm. Thirdly, the relationship of points correspondence between serial images are then applied to estimate camera parameters via computer vision technique. Finally, the 3D model map of buildings can augment to building images according to the camera parameters.

The main aim of this thesis is to propose a novel method for generalization of 3D building models with respect to topology in 3D space. The first part gives an overview over spatial data structures and methods for generalization of 3D objects. The second part presents the methodology composed of volumetric mo- del reconstruction, topology validation and simplification of geometry based on mathematical morphology approach to build multi scale model. Method is then implemented and experimental results are presented. In conclusion results are discussed and possible improvements are suggested.

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<p>The main problem that is addressed in this thesis is how to represent complex three-dimensional objects in GIS in order to render a more realistic representation of the real world. The goal is to present an approach for representing complex 3D objects in GIS. This is achieved by using commercial GIS (ArcGIS), applied to 3D properties. In order to get a clear overview of the state-of-the-art of 3D GIS and the current 3D cadastral situation a literature study was carried out. Based on this overview it can be concluded that 3D GIS still is in its initial phase. Current 3D GIS developments are mainly in the area of visualisation and animation, and almost nothing in the area of spatial analysis and attribute handling. Furthermore, the literature study reveals that no complete solution has been introduced that solves the problems involved in 3D cadastral registration. In several countries (e.g. Sweden, Denmark, Norway, Netherlands, Israel, and Australia) 3D properties exists in a juridical framework, but technical issues such as how to represent, store, and visualize 3D properties has not yet been solved. Some countries (Sweden, Norway, and Australia) visualize the footprints of 3D property units in a base map. This approach partly solves some technical issues, but can only represent 3D objects in a 2.5D environment. Therefore, research in how to represent complex objects in GIS as ‘true’ 3D objects is of great need.</p><p>This thesis will emphasize MultiPatch as a geographic representation method to represent complex 3D objects in GIS. A case study will demonstrate that complex objects can be visualized and analysed in a commercial GIS, in this case ArcGIS. Most commercial GIS software available on the market applies a 2.5D approach to represent 3D objects. The 2.5D approach has limitations for representing complex objects. There is therefore a need of finding new approaches to represent complex objects within GIS. The result shows that MultiPatch is not an answer to all the problems within 3D GIS but a solution to some of the problems. It still requires a lot of research in the field of 3D GIS, especially in development of spatial analysis capabilities.</p> / <p>Det huvudsakliga problemet i denna uppsats är hur komplexa tre-dimensionella objekt kan representeras i GIS för att återge verkligheten mer realistiskt. Målet är att presentera ett tillvägagångssätt för att representera komplexa 3D-objekt i GIS. Detta har uppnåtts genom att använda ett kommersiellt GIS tillämpat på 3D-fastigheter. En litteraturstudie har genomförts för att erhålla en klar översikt över det senaste inom 3D-GIS och över den aktuella situationen inom 3D-fastigheter. Grundat på översikten kan slutsatsen dras att 3D-GIS bara är i sin begynnelsefas. Den aktuella utvecklingen inom 3D-GIS har huvudsakligen fokuserat på visualisering och animering och nästan ingenting inom rumsliga analysmetoder och hantering av attribut. Litteraturstudien visar också att ingen fullständig lösning för de problem som finns inom 3D-fastighetsregistrering har introducerats. I flera länder, t.ex. Sverige, Danmark, Norge, Nederländerna, Israel och Australien, existerar 3D-fastigheter idag i juridiska termer, men de tekniska problemen som t.ex. hur 3D-fastigheter ska representeras, lagras och visualiseras har inte ännu lösts. Vissa länder (Sverige, Norge och Australien) visualiserar idag en projektion av 3D-fastigheterna på en fastighetskarta. Den här metoden löser endast några av de tekniska problemen och kan endast representera 3D-objekt i en 2,5D-miljö. Därför är forskning inom hur komplexa objekt kan representeras i GIS som s.k. ”sann” 3D av betydelse.</p><p>Den här uppsatsen framhäver MultiPatch som en datatyp för att representera komplexa 3D-objekt i GIS. En fallstudie visar att komplexa objekt kan visualiseras och analyseras i ett kommersiellt GIS, i det här fallet ArcGIS. De flesta kommersiella GIS som är tillgängliga på marknaden använder 2,5D-metoden för att representera 3D-objekt. 2,5D-metoden har vissa begränsningar för att representera komplexa objekt och därför finns det ett behov att finna nya tillvägagångssätt för att representera komplexa objekt inom GIS. Resultaten kommer att visa att MultiPatch inte är någon fullständig lösning till alla problem inom 3D-GIS men en lösning på några av problemen. Det krävs fortfarande mycket forskning inom 3D-GIS, särskilt inom utveckling av rumsliga analysmetoder.</p>

Sunshine, air and water are the vital elements to the human. This study investigated the insolation and solar radiation in Kaohsiung city. Solar radiation on the horizontal and declined plane was calculated. Sun shadow model for urban buildings was constructed for computing accumulated sunshining hours. Horizontal and vertical building shadows were displayed in ArcGIS ¡V the GIS software. Raster-based data model was used to analyze the effect of sun shadow shading by neighbour buildings. And the effect of shadow shading for solar water heater was also investigated. According to the results, minor installation error of orientation and decline angles of solar panel will not cause major energy loss. And the distance between the buildings¡Bthe height difference and the orientation between buildings are most important factors which affect optimal installation location of the solar water heater. If there are buildings located to the south, southeast and southwest, and the stories difference between buildings is over three, the installing location should be moved toward north. If buildings are next to each others and the variation of height is large, the efficient of receiving solar radiation will be deteriorated. The larger is the distance between buildings, the better the energy received.

The main problem that is addressed in this thesis is how to represent complex three-dimensional objects in GIS in order to render a more realistic representation of the real world. The goal is to present an approach for representing complex 3D objects in GIS. This is achieved by using commercial GIS (ArcGIS), applied to 3D properties. In order to get a clear overview of the state-of-the-art of 3D GIS and the current 3D cadastral situation a literature study was carried out. Based on this overview it can be concluded that 3D GIS still is in its initial phase. Current 3D GIS developments are mainly in the area of visualisation and animation, and almost nothing in the area of spatial analysis and attribute handling. Furthermore, the literature study reveals that no complete solution has been introduced that solves the problems involved in 3D cadastral registration. In several countries (e.g. Sweden, Denmark, Norway, Netherlands, Israel, and Australia) 3D properties exists in a juridical framework, but technical issues such as how to represent, store, and visualize 3D properties has not yet been solved. Some countries (Sweden, Norway, and Australia) visualize the footprints of 3D property units in a base map. This approach partly solves some technical issues, but can only represent 3D objects in a 2.5D environment. Therefore, research in how to represent complex objects in GIS as ‘true’ 3D objects is of great need. This thesis will emphasize MultiPatch as a geographic representation method to represent complex 3D objects in GIS. A case study will demonstrate that complex objects can be visualized and analysed in a commercial GIS, in this case ArcGIS. Most commercial GIS software available on the market applies a 2.5D approach to represent 3D objects. The 2.5D approach has limitations for representing complex objects. There is therefore a need of finding new approaches to represent complex objects within GIS. The result shows that MultiPatch is not an answer to all the problems within 3D GIS but a solution to some of the problems. It still requires a lot of research in the field of 3D GIS, especially in development of spatial analysis capabilities. / Det huvudsakliga problemet i denna uppsats är hur komplexa tre-dimensionella objekt kan representeras i GIS för att återge verkligheten mer realistiskt. Målet är att presentera ett tillvägagångssätt för att representera komplexa 3D-objekt i GIS. Detta har uppnåtts genom att använda ett kommersiellt GIS tillämpat på 3D-fastigheter. En litteraturstudie har genomförts för att erhålla en klar översikt över det senaste inom 3D-GIS och över den aktuella situationen inom 3D-fastigheter. Grundat på översikten kan slutsatsen dras att 3D-GIS bara är i sin begynnelsefas. Den aktuella utvecklingen inom 3D-GIS har huvudsakligen fokuserat på visualisering och animering och nästan ingenting inom rumsliga analysmetoder och hantering av attribut. Litteraturstudien visar också att ingen fullständig lösning för de problem som finns inom 3D-fastighetsregistrering har introducerats. I flera länder, t.ex. Sverige, Danmark, Norge, Nederländerna, Israel och Australien, existerar 3D-fastigheter idag i juridiska termer, men de tekniska problemen som t.ex. hur 3D-fastigheter ska representeras, lagras och visualiseras har inte ännu lösts. Vissa länder (Sverige, Norge och Australien) visualiserar idag en projektion av 3D-fastigheterna på en fastighetskarta. Den här metoden löser endast några av de tekniska problemen och kan endast representera 3D-objekt i en 2,5D-miljö. Därför är forskning inom hur komplexa objekt kan representeras i GIS som s.k. ”sann” 3D av betydelse. Den här uppsatsen framhäver MultiPatch som en datatyp för att representera komplexa 3D-objekt i GIS. En fallstudie visar att komplexa objekt kan visualiseras och analyseras i ett kommersiellt GIS, i det här fallet ArcGIS. De flesta kommersiella GIS som är tillgängliga på marknaden använder 2,5D-metoden för att representera 3D-objekt. 2,5D-metoden har vissa begränsningar för att representera komplexa objekt och därför finns det ett behov att finna nya tillvägagångssätt för att representera komplexa objekt inom GIS. Resultaten kommer att visa att MultiPatch inte är någon fullständig lösning till alla problem inom 3D-GIS men en lösning på några av problemen. Det krävs fortfarande mycket forskning inom 3D-GIS, särskilt inom utveckling av rumsliga analysmetoder.

Generalization of LOD2 building models using the aggregation method Abstract The thesis proposes and implements a method of 3D building models aggregation. The procedure achieves global optima by the means of mathematic optimization. Buildings are aggregated according to similarity characteristics typical for LOD2, e. g. roof type. Aggregation process is driven by minimalization of volume changes and of the aggregate count. The optimization problem was implemented as a Python script with optional parameters to meet custom demands of a wide range of users. Input data models of buildings are created by the method of procedural modelling. Its outcome is further restructured into form of continuous blocks. Finally, the visualization procedure is designed and implemented to illustrate the results of optimized aggregation of 3D building models. Keywords: 3D GIS, generalization, aggregation, mathematical optimization, procedural modelling

Les données géographiques 3D sont de plus en plus courantes et modélisent de manières variées le territoire. Elles sont souvent utilisées pour mieux comprendre la ville et ses phénomènes sous-jacents en intégrant de nombreuses informations (environnementales, économiques, etc.) pour l'appui à l'aménagement du territoire. À l'échelle locale, le plan local d'urbanisme (PLU) décrit les connaissances régulant le développement urbain, incluant des contraintes tri-dimensionnelles (par exemple : hauteur maximale d'un bâtiment ou surface de plancher) que doivent respecter les nouveaux bâtiments. Ces contraintes sont rédigées dans un format textuel, difficile de compréhension pour le non-initié et dont l'interprétation sur un territoire donné est complexe. L'objectif de cette thèse est de montrer comment les données géographiques 3D permettent d'exploiter les règlements locaux d'urbanisme à travers deux usages : la vérification de règles d'urbanisme et la proposition de configurations bâties. Notre méthodologie s'appuie sur une modélisation de l'espace urbain, représentant les objets pertinents mentionnés dans les règlements, support d'une formalisation des règles avec le langage OCL. La proposition de configurations bâties est réalisée grâce à une méthode d'optimisation basée sur un recuit simulé trans-dimensionnel et une technique de vérification du respect des règles / 3D geographic data are very frequent and represent territories in various ways. Such data are often used to better understand cities and their underlying phenomena by integrating different information (environmental, economic, etc.) to support urban planning. On a local scale, the French Local Urban Plan (PLU) describes constraints that regulate the urban development, notably through tri-dimensional constraints (for example by defining a maximal height or by limiting built area) that new buildings must respect. These constraints are compiled in a textual format. They are difficult to understand for non experts and their impact for a given territory is complex to assess. The aim of this thesis is to demonstrate how 3D geographic data enable the exploitation of local urban regulation constraints through two different uses: the verification of the respect of constraints and the generation of building configurations. Our method relies on a model of the urban environment, representing relevant objects according to regulations. This model supports the formulation of the constraints with the OCL language. The generation of building configurations is processed by an optimization method based on a trans-dimensional simulated annealing relying on a rule checker

The terrorist attacks on New York City on September 11, 2001 heightened awareness about the need to plan for emergency evacuation measures. As a result, three-Dimensional (3D) city and building models have become an important part of GIS analysis. The technology can be used to plan evacuations in complex indoor environments. This thesis had two main objectives. The first goal was to conduct a 3D network analysis of a building for emergency management, which was based on a 3D model of a building in the city of Gävle, Sweden. This 3D model identifies the shortest path from any room to the defined exit. The second objective was to test the predicted evacuation times with a simulation experiment. The 3D model was built by Google Sketch Pro 8 and the 3D network analysis was mainly conducted in the ESRI’s ArcGIS software. The simulation experiment involved 18 volunteers at the organization Future Position X. The 3D network analysis was based on distance measurements instead of GNSS coordinates. The simulation experiment was conducted in four different situations. Crowding was found to be a critical problem during evacuation. Evacuation speeds varied from normal walking to running. However, crowding always increased the evacuation time and thus would affect the survival rate. Evacuation routes should be distributed differently to reduce this problem. The thesis also identifies other factors to be considered when planning emergency routes and challenges posed by the software at this time.