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This thesis is about the visualization of a Tetrahedral Irregular Network (TEN) in a web client. A tetrahedron is the simplest geometric form in 3D space, a pyramid with a triangular ground face. Its four points can lie anywhere in the 3D space as long as they do not lie on one plane. 3D objects can be composed from multiple tetrahedra. In a fully partitioned TEN even air and soil are modeled with tetrahedra. Most GIS analyses on a TEN can be deducted to an operation on the triangle simplex, therefore 3D analysis on A TEN is relatively easy compared to analysis on another 3D data structures. Chapter one (Introduction) gives an overview of the background of the research, the objectives, the requirements and the research methodology. In Chapter two (Data models for 3D geo-information) the theory around 3D data modeling is given. It starts with an explanation of the 3D feature components. In the next part, there is a comparison of 3D data representations and 3D data models and a conclusion is drawn why the TEN is the best data model. In the next paragraphs, theory on the TEN data models is given as well as theory on the derived 3D TIN and ‘TEN view’ data model. In addition, this chapter gives information how to build up a TEN dataset, about 3D topology and a comparison is made how 3D spatial (TEN) data can be stored in a database. Chapter three (Prototype related technology) gives information about XML based standards to exchange and visualize 3D and 2D data and about any other technologies that are used in the prototype made for this thesis. In Chapter four (Review of 3D GIS applications on the web) a number of 3D web GIS prototypes are discussed which have been created in the last decennium. In addition to a description of them, the prototypes are compared on a number of features and a feasibility review is done of each prototype. Some prototypes are picked out and a conclusion is made which are the best prototype examples for the development of the prototype of this thesis. In Chapter five (Prototype architecture) first the preliminary draft of the prototype is discussed. Secondly, the chapter gives a schematic overview of the realized architecture and a description of the main components and techniques of the prototype. Thirdly, the steps that have been taken over time to develop the prototype are listed. In Chapter six (Prototype components, dataset and techniques) first each component of the prototype web application is described which are a 3D view, a 2D view, a Table view, a Titlebar and an SQL box. Secondly, information is given about the datasets that have been used. Thirdly, each technique used in the prototype is explained in detail In addition some techniques that are not implemented in the prototype are discussed too. Chapter seven (Evaluation and conclusion) starts with an evaluation. First, a comparison is made which XML based language is best for 3D TEN visualization: X3D, KML, or CityGML. Secondly is reviewed in which way the data can best be stored in the database. Thirdly is compared whether it is best to visualize the TEN, 3D TIN, or TEN view. As fourth, the architecture is discussed. In the next part of Chapter six (Summary and conclusion) each sub question as stated in the Chapter one is answered. In addition, an answer is given on the main research question. Finally, remarks are made regarding feature research and recommendations.

The main objective of this research project was to assess the quality and feasibility of the guidelines for INSPIRE Network Services. The completeness, clarity, consistency and ease-of implementation of the guidelines were considered. Part of this assessment is also the question: how can INSPIRE compliance be tested and measured? The topic was tackled both from a theoretical and a practical point of view. The theoretical part of the project included a detailed investigation and assessment of the INSPIRE requirements and recommendations as regards: technical architecture of the services, functionality of the particular network services, quality of services, rights management issues, elements of spatial data and metadata models. This part of the project has been finalized with the synthesis of the guidelines derived from the INSPIRE documentation. The review of the INSPIRE documents showed that these guidelines are specific and clear enough in most points, however not yet complete. The status of work as regards the technical guidelines for particular INSPIRE Network Services is different. The topic which calls for particular attention is the adaptation of the INSPIRE services to SOAP bindings. Another item that is needed and that is currently missing in the guidelines is the provision of more strict rules for compliance testing (Abstract Test Suites (ATS) for INSPIRE services and data) and quality of service (QoS) testing. The practical part of the project was the implementation of some prototype View and Download services. For the implementation of the prototype services existing software was chosen, namely GeoServer, one of the spatial data server products implementing the OGC standards. The specific scenario chosen for the case study are web services for a national park. The spatial data for the prototype was acquired from the resources of the Narew National Park (Poland). The prototype was realized in order to validate and evaluate whether the Implementing Rules and other guidelines contained all necessary information to set up INSPIRE compliant web services, with special attention to the question how this ‘compliance’ can be measured using both manual and automated testing methods. First, the prototype has been evaluated for the compliance with INSPIRE guidelines by manual inspection of the prototype services. Secondly, the compliance test methodology proposed by OGC has been used to perform automated tests on the GeoServer instance. The evaluation of the prototype showed that the web services provided with GeoServer fulfill the majority of requirements for View/Download Services through the WMS/WFS functionalities (mandatory operation parameters, offered output formats etc.) Some elements need to be configured within GeoServer (e.g. the required spatial reference system, layer/feature type names that conform to the INSPIRE data specifications). Still, some INSPIRE-specific extensions to the functionality provided by GeoServer are needed for both services (support of the SOAP/POST methods for the service operations, solutions for multilingual aspects of services and rights management). Another requirement for the INSPIRE-conformant web services is that the spatial data and metadata are provided compliant with the data models required by INSPIRE. The study on compliance testing methodologies is followed by the recommendation that the standards and testing programs from ISO and OGC can be of particular relevance for the development of Abstract Test Suites for INSPIRE services. The reference framework for INSPIRE compliance testing can be partially based on the OGC Compliance & Interoperability Testing & Evaluation Initiative (CITE) testing program. The OGC tests are especially suitable as reference since the core technical specifications for implementation of the particular INSPIRE Network Services are the OGC web services specifications.

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.