Automated Search and Management for Geographical Web Services

Abstract

This thesis holds the result of a study in focused web-information search, retrieval and management of retrieved data. Focused web-information search means that the search is exclusive for one type of content or topic. The only topic examined in this search is OGC web-services. More specifically, URLs to OGC web-services are searched for. Of course, many of the techniques utilized and discussed in this thesis are of possible interest also for other topics. The OGC web-services are basically services for online geospatial data management,such as online maps and coverage data. In detail this study examines how one can effectively locate a large amount of these OGC-services on the web. That is some techniques, such as meta-search and web-crawling are examined. Also after an evaluation of the methods examined, the most effective methods are combined into a search-system prototype. The search-system is made for autonomous, effective and stable retrieval and management of the location of the OGC web-services. This work was carried out at Carmenta AB. The testing of retrieval techniques in this thesis have generated the location of a total of approximately 2600 online high-quality OGC-services. The prototype have only been partially developed, but it is estimated to be capable of discovery of approximately 3000 online services in a session of 33 hours.