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De afstudeeronderzoek is gericht op de vraag 'Hoe kan een 3D-GIS voor grootschalige toepassingen worden opgezet. De nadruk ligt hierbij niet op visualisatie, maar op de opslag van de gegevens en op de analysegereedschappen in drie dimensies. Visualisatie is wel van invloed op met name de opslag van driedimensionale gegevens. Er bestaan verschillende technieken om objecten geometrisch te modelleren. Veel van deze technieken zijn bedoeld voor CAD-toepassingen en voor visualisatie. Voor toepassing in een 3D-GIS zijn de meest geschikte objectrepresentaties:: Boundary Representation (B-Rep); Cell Decomposition; Spatial Occupancy Enumeration (SOE). De keuze uit bovenstaande opsomming is afhankelijk van het doel van de representatie. Voor een algemene driedimensionale GIS, waarin zowel bewerking als visualisatie van de 3D gegevens wenselijk is, is een bijzondere vorm van Cell Decomposition, namelijk het Tetrahedral Network (TEN)) het meest geschikt. Een TEN is een datastructuur waarbij de objecten opgebouwd worden uit niet-overlappende tetrars en is de tegenhanger van Triangular Irregular Networks (TIN). De TEN heeft de voordelen, dat vrijwel elike vorm te benaderen is, dat een snelle visualisatie mogelijk is, en dat de operaties op en met objecten gemodelleerd in een TEN gemakkelijk zijn. De topologische structuur van een TEN is sterker dan bij de B/Rep, SOE en Cell Decomposition met willekeurig gevormde cellen, omdat de cellen eenvormig zijn en de relaties tussen naburige cellen en hun elementen, en tussen de elementen van een individuele cel vastliggen, evenals het onderscheid tussen interieur, grens en exterieur. Een GIS-datastructuur moet naast geometrie en topologie ook thematische informatie vastleggen. Een 3D GIS stelt bovendien de eis, dat de gegevensstructuur de opslag van een verschillend aantal abstractieniveaus (Levels-of-Detail) mogelijk maakt. Een objectgeoriënteerde structuur voldoet aan die eisen. In dit afstudeeronderzoek is de buffer als analysegereedschap verder uitgewerkt, omdat vertaling naar drie dimensies een aparte benadering behoeft. Het genereren van een 3D buffer verdient grotere aandacht omdat het afstandsverschil tussen een ideal en een gegenereerde buffer, dus het verschil tussen twee volumes, in drie dimensies optreedt. Het genereren van een 3D buffer op basis van een TEN is zowel voordelig bij de constructie zelf, als bij de verdere verwerking, omdat de buitenwereld van een object in een TEN bekend is. De theoretische opbouw van een 3D bufer is getest door een buffelalgoritme te programmeren m.b.v. CGAL (Computiational Geometry Algorithms Library). Het programma laat zien dat de theorie klopt en dat een 3D afgeronde buffer met een simpele code te genereren is voor een object dat gemodelleerd is in een TEN. Hier bewijst het nut van een sterke topologie zich.

The aim of this master thesis has been to answer the question: How can a vario-scale IMGeo be designed and developed by applying the constrained tGAP structure with Top10NL as initial constraint? This research has been done under authority of Gemeentewerken Rotterdam and TU Delft. For Gemeentewerken Rotterdam the main goal is to investigate the possibilities of automatic generalisation based on their project "Basisregistratie Geografie", for TU Delft the main goal is to see the concept of the constrained tGAP structure being investigated. The models IMGeo, a new large scale topographical standard in The Netherlands, and Top10NL, the authentic registration for medium scale topography in The Netherlands, are both derived from NEN 3610; they form the basis for the generalisation in this research. The main differences are explained by their backgrounds. IMGeo originates from the GBKN, whereas Top10NL is based on Top10Vector. The fact that these models are not made cooperatively is bad luck for this research; no object class hierarchy could be made from these models, because there are object classes in Top10NL which don't even exist in IMGeo. The Top10NL object classes therefore can't be seen as a generalisation of the object classes of IMGeo. The generalisation approach in this research was the constrained tGAP structure, a concept from the universities of Hannover and Delft. In this research IMGeo objects were assigned to Top10NL regions. Four possible methods to assign IMGeo objects to Top10NL regions were developed: - Simple overlay method. An intersection between the models where every IMGeo object is split at the borders of the overlapping Top10NL object. In the end result only Top10NL geometry will be visible. - The maximum area method. The Top10NL object which overlaps the IMGeo object the most is the shape to which the whole IMGeo object is assigned to. The IMGeo geometry is kept in this method. - The 35%-split method. If an IMGeo object belongs for more than 35% to two Top10NL objects we consider this Top10NL geometry as enrichment of the structure; therefore the IMGeo object is split and a new IMGeo object is created. For all IMGeo objects that don't have two Top10NL objects overlapping for more than 35% the maximum area method is applied. - The building first method. This method assigns IMGeo-buildings to a building region in case of some overlap with a Top10NL building without considering the amount of overlap. The other IMGeo objects are selected as in the maximum area method. The building first method has been developed because the results of the maximum area method and the 35%-split method were unsatisfying. This building first method gives the best results of the four methods. With this method further research was done. For the test dataset from the municipality of Almere class weights and class compatibilities have been derived, which are input values for the tGAP structure. This has been done after tuning the weights and compatibilities of the constrained tGAP structure and comparing the end result to the Top10NL dataset. Final conclusion of this report is that the constrained tGAP absolutely offers possibilities for automatic generalisation from large to medium scale data. However, the amount of pre-processing of the data and the state of development of the tGAP structure are reasons for a governmental organisation like Gemeentewerken Rotterdam to not yet develop a product like this. A topological structure of the models might possibly solve these problems. Cooperation between researching parties, industrial parties and governmental organisations in projects like DURP Ondergronden could be a good opportunity to develop a vario-scale IMGeo as described in this report.

Accurate postal code maps have many applications within GIS as the postal code has the potential to link the address description of buildings to their location in a specified global reference system in a more natural way. This relationship is possible in both directions: geocoding and reverse-geocoding. These operators demand a mechanism for translating an exact geometric position (i.e., WGS84 coordinate) into a location indication (town, street, house number) and vice versa. As most built-up parcels are provided with a postal code, this indicator can be used as the linkage. This thesis describes the procedure, based on the Dutch cadastral registration, to obtain a reliable 6-position (i.e., 2628BX, the highest level of detail possible) planar postal code map for the Netherlands. Problems with existing, Voronoi-diagram based, postal code maps, like intersected houses and arbitrary derived (and thus unrecognizable) boundaries are avoided. The reliability of the derived planar postal code map is discussed and results are illustrated by figures. For a planar coverage, non built-up parcels having no postal code should be assigned a plausible postal code. Furthermore special attention is given to infrastructural parcels. These parcels are divided at their (approximated) skeletons first and then these subdivided infrastructure parcels are piecewise attached to their neighbour parcels. This new approach results in very reliable postal code maps, which are visually attractive too as infrastructure lines can be recognized. The procedure is generic and can be applied to other administrative parcel information as well. The algorithm is implemented using the Computational Geometry Algorithms Library (CGAL), and the possibilities and limitations of this library are addressed as well. Also a number of non-implemented alternatives or improvements are given.

With the increase of the availability of large-scale geographic data set and the rise of widespread computer networks, such as the Internet, the need has arisen to be ableto transfer this data by means of these networks. The networks form the basis for a Geographic Information Infrastructure (GII), in which data users, data providers and data producers are connected with each other.There also exists the need to offer this data on several scales to end users, for example to get an overview of an area first. Because the geographical information are now sent by the computer networks and large-scale geographic information brings many data, data reduction must take place. This is to prevent that sending of the information takes too much time. Generalization of geographical information is a possible means to let this reduction take place.Generalization is the selection and simplification of detail appropriate to the scaleand or purpose of the map. The appliance of generalization demands that choices mustbe made with respect to which geographical objects are selected and simplified and how this selection and simplification must take place. Moreover, also the surroundings of the objects to be generalized, are often taken into account in the generalization process, which makes that the complete process even requires more time. This way, the complete process can not be carried out in real time.Earlier, reactive data structures, in which geographical information is stored in the computer with several levels of detail, have been proposed as a solution to allow the use of generalized large-scale geographical information in real time. So far, these data structures were using redundancy with respect to geometry. For this reason a new conceptual model has been developed, where a number of existing data structures have been combined into two new data structures, namely, the GAP face tree and the GAP edge forest (described in Van Oosterom, 2005). The complete structure is termed tGAP structure, inwhich tGAP stands for topological Generalized Area Partitioning.The tGAP structure has not been theoretically verified, nor implemented or tested. Therefore, the objective of this research is to theoretically verify the data structures and to test the data structures considering requirements such as loading time and storage capacity.To reach the objective literature study has been performed in the field of generalization, database management systems and the data structures. Moreover, a prototype has been built, with which the data structures have been implemented in a mainstream database management system (DBMS) with spatial data types. Literature study has shown that generalization is a key issue in the complete process of obtaining and processing geo-information and that using reactive data structures is asuitable option to offer the results of generalization within a GII in real time.The implementation of a prototype has shown, that it is possible to implement thedata structures in a mainstream DBMS. The data structures are implemented in Oracle Spatial, the DBMS, and by means of Apache, a web server, opened up to Google Earth, a geographical viewer. The data structures in the prototype make it possible to view thegeographical data interactively within the viewer independent from the size of the area to be loaded.The final conclusion must be, that with some workarounds and with some changes tothe proposed conceptual model, it is possible to implement the model as described in (Van Oosterom, 2005). With an implementation it becomes possible to show geographical data on a variable number of detail levels and the implementation shows that the data structures can provide the desired data reduction within a GII in real time.

The main research questin is: Which geographic data sets can support the need of information regarding the work processes 'Maintenance of the Highway Network' at the Dienstkring and what level of quality of the geographic data is necessary. The current situation at the Directorate-General increases the complexity of the research question. Commonly organizations with stable processes (and need of information) are preferred to investigate the need of information. At the Directorate the situation is more dynamic, because of reorganization. Therfore the role of the Dienstkring and their appoaches and procedures, regarding maintenance, are changing. Also new instrument, performance contracts (also called innovative contracts), has to be uesed to control maintenance of the highway network. The fitnes of use of the geograpbic data sets is focused at the objects (including thematic attributes) stored in the data set and the quality parameters: geometric accuracy and up-to-dateness. The need of information according to the users is presented in Object Models. According to directives from the Head Office, performance contracts have to be used instead of traditional contracts. The need of information will be investigated while using traditional contracts as well as performance contracts. To control and structure the different problems, the Integrated Architecture Framework developed by Cap Gemini has been used. By stating the work processes regarding maintenance of the Highway Network at a detailed level, the need of information should become clear. The need of information is presented by different Object Models separated by the themes: Pavement, Traffic Requirements, Nature and Environment, Exploitation and Civil Infrastructures. Also distinction by traditional contract or performance contract has been made. These Object Models will be used to relate to the data sets (and applications). Besides the desired objects and quality parameters, also the functionality (operations) of the applications has been invested. The main research question should be answered from the perspective of a Spatial Data Infrastructure (SDI). A SDI consists of four elements: policy and organization; geogrraphic data; technology to store, communicate and use geo-informatin; standards for description, exchange and relating geo-information. All these elements contain parts of the answer to create an optimal information supply. Only mentioning geographic data sets (with Object Models and quality parameters) wouldn't be useful. It can be concluded that usage of performance contracts requires a geographic data set with the characteristics of the Object Model presented in Supplement 19. Although only usage of this data set won't improve the information supply. Long term solutions require the developoment of a SDI. Starting with a SDI on RWS level (corporate SDI) and participation at an SDI on national level (National SDI) is recommended. Besides conclusions about the data sets also conclusions about the used method can be presented. Finally some recommendations are presented.

The quick rise of the possibilities of the internet has caused an increased use of Geographic Information Systems (GIS). Internet provides a platform to distribute geographical data. However, most of the current geographic sites are atlases and not GIS products, because they are short of possibilities for analysis, query and visualisation. A new development in internet GIS is the use of distributed sources: the user can make his choice between diverse datasources. Geographic data is currently delivered as the data itself and meta-data like format, projection, attribute-definition, actuality and accuracy (quality of the data). The metainformation enables the user to decide whether the data is suitable for the use in a GIS. The OpenGIS Consortium (OGC) is developing standards for interoperability of geographic data. In the case when multiple sources are used, the visualisation of the datasets can cause conflicts for there is no standard or direction for the graphical presentation of the data. Therefore, it's useful to make a distinction between the Digital Landscape Model (DLM) where the data itself is present, and the Digital Cartographic Model (DCM, in Dutch DKM) where the graphical presentation is described. For the use of an internet GIS, it is important that not only the DLM, but also the DKM is provided by the data source. When a combination of several DLM's is made, the use of an expert system is needed, which uses cartographic rules to determine the optimal presentation of this set of data, given the user's task and preferences. This Cartographic Expert System (CES, in Dutch KES) is aimed to accompany and advise the user in producing a cartographic decent product.

Since Web Feature Services can be used to edit geographic data over internet, Web Feature Services should be able to process geometric transactions. Therefore for this MSc research project, the following research question has been answered: How should geometric transactions be processed in a distributed GIS using OpenGIS Web Feature Services? To answer this question literature has been studied and a case study has been done to develope a Web Feature Service (WFS). With this service, the abilities of WFS to process geometric transactions have been analyzed. For editing the cadastral data, one could think of a notary who drafts a new boundary, because a parcel haz to be split. This principle has been used in the case study. Both a WFS and a client have been implemented. The WFS is composed of an Oracle Spatial 9i database, with GeoServer (an Open Source WFS) configured on top of it as web feature server. GeoServer has been installed in Tomcat (a Java servlet container) to provide internet access. Because the tested existing WFS-clients were either not fully compliant with the specification, nor transational or it would have cost too much time to adapt them for the case study service, a client needed to be developed in this research. The developed client uses Scalable Vector Graphics (VGS) in a standard web-browser for visualization and editing of features graphically. Java Server Pages (JSP) have been used to implement functionality to compose and send the transaction request. This way, functionality of the cient is divided between a browser and a Java web server.Interoperability tests with other than the developed client showed that not all currently available clients that claim to be WFS-compliant, work correctly. However, the tests also showed the power of interoperable services, since a generic client - not having any knowledige of the data source - could retrieve features from the data source, because a WFS was configured on top of it. The case study showed that, in general, the WFS-specificiation provides sufficient operations to make sure that geometric transacations can be sent from client to server and can e processed successfully. Using general web technologies as HTTP, XML and GML, geographic features can be retrieved, created, modified and deleted. However, WFS misses operations to deal well with constraints and other application logic and misses some useful operations to deal with complicated data sets and transactions. The main conclusion is that, although EFS is not advanced to strongly support transactions on complicated (e.g. withc topology or other spatila constraints) data sets in a generic way, WFSs are suitable and powerful interoperable GIS web services to edit geographic data over large networks as the internet.

he increasing availability of digital camera devices and camera phones enable users to capture and upload digital photos at any a time and any place. Online image collections face the problem organizing increasing photo collections. Because users experience adding qualitative photo annotations as a time-consuming and tedious task, they omit to do it. However, good photo annotation is very important for fast and reliable photo retrieval. The integration of positioning devices (e.g. GPS) with digital camera enables to capture position along with the photo and this location metadata has been applied in previous research to automatically caption digital photos. The disadvantage of describing a photo using location metadata only is that it only enables to add information about its surrounding and not about the actual objects pictured. This research carried out in the framework of the EU research project Tripod assumes in the near future camera devices integrated with GPS and digital compass will be available. Using this full spatial metadata, it is possible to exactly identify and localize objects inside the pictured scene. Digital photos with 3D position and view direction are collected on the Market Square in Delft (The Netherlands) using a Topcon imaging total station and Nikon D100 camera mounted with digital 3-axis compass and GPS to carry out a proof-of-concept. Using the output of a perspective viewer service, a tool that renders an three-dimensional model, a virtual abstraction that matches the digital photo is created to be able to identify and localize visible objects in order to place a label next to it. The three-dimensional models applied for this research are created from conventional GIS datasets (e.g. TOP10NL and GBKN) and a digital elevation model (AHN) by extruding the building footprints. The best possible for a label is defined at the empty areas and constraints and rules are added to ESRI ArcGIS label Engine Maplex to carry out the label placement inside the digital photo in a GIS environment. Misidentification and misplacement due to lens distortions, and GPS and compass inaccuracies are evaluated. A demo-application is developed in ESRI ArcGIS using Visual Basic for Applications (VBA) programming and system architecture is proposed for implementation of a photo labelling service. It is concluded that the virtual scenes as output of perspective viewer services are appropriate to apply for object identification and localization. In doing so, the problem of label placement in three-dimensional geographic environments is reduced to a two-dimensional map-labelling problem. The best location of label placement is determined using constraints and rules to be applied to the virtual scene and the reclassified-to-binary image of the input photo, and the depth map enables to vary in label font size depending on the object distance.

Planning and designing mobile telephone networks is a complicated process, which involves large amounts of money. The TIGER tool is under development at TNO ICT. The tool calculates the spatial traffic grids, which are one of the input data sets for mobile telephone network planning tools. The input data for the TIGER tool consists of the distribution of the potential users of the mobile telephone network. The distribution of the traveling users is only available at low detail and this data set has to be matched with the detailed road and railroad data set. The match of both data sets should be optimized and an indication of the reliability and accuracy of the matches has to be given. In order to perform this task properly the follwing research question has been formulated. Find the best match between generalized, low detailed schematic links and the more detailed road and railroad network and give an indication of reliability and accuracy of the results. This graduation project has been executed in two ways. First an eximanation of related researchers on the topic of matching multiple representations of street data sets has been performed. Second, different variants of solution definitions have been implemented. The results have finally been compared in order to give an indicaation of the reliability and accuracy. This best variant has the highest matching rate of all of the implemented variants, determined by comparing the results of the variants mutually. The variant generalizes the matching route of the travelers with the Douglas-Peucker line simplificatin algorithm. The number of vertices that are left gives an indication of the smoothness of the route, which i sone of the characteristics of the input data set containing the distribution of the travelers.

The master of science thesis project called "The Land Administration Domain Model 'Survey Package' and Model Driven Architecture" will be described and concluded in this report. The main subjects for the research are the Land Administration Domain Model (LADM), specifically the Survey Package, dealing with survey measurements. Secondly, the Model Driven Architecture (MDA), a software design methodology to generate platform specific information systems based on platform independent models, specified in the Unified Modelling Language (UML) and the Object Constraint Language (OCL). A custom developed MDA Prototype has been developed, aiming at the implementation of the Adapted LADM 'Survey Package' in a PostgreSQL/PostGIS object-relational database. Thirdly, an analysis of the quality of the Dutch cadastral map is performed, based on data loaded into this the Adapted LADM 'Survey Package' PostGIS database.