User generated spatial content sources for land use/land cover validation purposes : suitability analysis and integration model

A thesis submitted in partial fulfillment of the requirements for the degree of Doctor in Information Management, specialization in Geographic Information SystemsTraditional geographic information has been produced by mapping agencies and corporations, using high skilled people as well as expensive precision equipment and procedures, in a very costly approach. The production of land use and land cover databases are just one example of such traditional approach. On the other side, The amount of Geographic Information created and shared by citizens through the Web has been increasing exponentially during the last decade, resulting from the emergence and popularization of technologies such as the Web 2.0, cloud computing, GPS, smart phones, among others. Such comprehensive amount of free geographic data might have valuable information to extract and thus opening great possibilities to improve significantly the production of land use and land cover databases. In this thesis we explored the feasibility of using geographic data from different user generated spatial content initiatives in the process of land use and land cover database production. Data from Panoramio, Flickr and OpenStreetMap were explored in terms of their spatial and temporal distribution, and their distribution over the different land use and land cover classes. We then proposed a conceptual model to integrate data from suitable user generated spatial content initiatives based on identified dissimilarities among a comprehensive list of initiatives. Finally we developed a prototype implementing the proposed integration model, which was then validated by using the prototype to solve four identified use cases. We concluded that data from user generated spatial content initiatives has great value but should be integrated to increase their potential. The possibility of integrating data from such initiatives in an integration model was proved. Using the developed prototype, the relevance of the integration model was also demonstrated for different use cases

The web feature service: transaction standard: an example of prototype implementation

Trabalho de Projecto apresentado como requisito parcial para obtenção do grau de Mestre em Ciência e Sistemas de Informação GeográficaWith the Internet growth, the production and amount of available geographic data also increased. There are, at the moment, many servers around the world providing spatial information to several users, and many of them are accessing this information through different Geographic Information Systems (GIS) applications. Therefore, it becomes necessary to develop standards in order to solve the interoperability problem inherent to this heterogeneous and distributed data. This work aims at showing the significance of standards, particularly the Web Feature Service - Transaction (WFS-T) standard in the Geographic Information (GI) domain. A prototype that provides GI according with this standard is also implemented, based on PostgreSQL/PostGIS, GeoServer, uDig, Apache and MapFish