Models de dades dels SIG a Internet. Aspectes teòrics i aplicats

Abstract

There is abundant scientific literature on geographical information standards, particularly in relation to spatial data infrastructures. However, there are only a few studies on the implications of implementing them and the difficulties involved, or on their use in cartography and the remote sensing fields. This thesis analyses the scope of applying international standards, and identifies some overlaps and gaps in certain areas. Proposals are also made to fix the problems in both the implementations and the standard documents themselves. One problem we observed is that the different standards are not completely connected. Therefore, we propose defining a new technological framework that makes it possible to restructure the architectural style used in the spatial data infrastructures, which is currently service oriented. We propose changing it to a resource oriented architectural style, which would improve the use of the Internet and relate resources better in a way that a single World Wide Hypermap (WWH) is created. The WWH incorporates other collectives better, such as those that join the open data policies and standards, the volunteered geographic information groups, the mass market map browsers and the virtual globes. While carrying out this work we have been actively involved in the process of defining international standards, which has led to the development of the Web Tile Map Service (WMTS) document that has been ratified as a standard by the Open Geospatial Consortium (OGC). At the same time, we have tested technological implementations with real data in order to detect problems in the specification documents and in their implementations. Adjustments to these specifications have been proposed when appropriate. Furthermore, this PhD thesis quantitatively analyses different products from different map service providers (including MiraMon implementations) and assesses the extent to which the proposed improvements contribute to increasing the performance of the implementations. In this regard, this document makes a specific proposal for using JPEG2000 in Web service implementations that simultaneously integrates the Web Map Service (WMS), Web Map Tile Service (WMTS) and Web Coverage Service (WCS). We have also incorporated some of the proposed specifications and solutions into the MiraMon software (desktop, map browser and map service) in order to test and validate them. Moreover, we have designed some ways of optimizing the algorithms that implement previous proposals, and an implementation of the REST approach has been suggested for MiraMon. Finally, we propose a specific implementation that includes end-user contributions (user feedback), so that they complement the current metadata catalogues.

Date of Award	15 Jun 2012
Original language	Catalan
Supervisor	Xavier Pons Fernandez (Director)