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The W3C Semantic Sensor Network Incubator group (the SSN-XG), as one of its activities, produced an OWL 2 ontology to describe sensors and observations the SSN ontology, available at http://purl.oclc.org/NET/ssnx/ssn. The SSN ontology can describe the capabilities of sensors, the measurement processes used and the resultant observations, and can be aligned(More)
In this paper, we develop a semantic annotation technique for location-based social networks to automatically annotate all places with category tags which are a crucial prerequisite for location search, recommendation services, or data cleaning. Our annotation algorithm learns a binary support vector machine (SVM) classifier for each tag in the tag space to(More)
This paper presents an overview of ongoing work to develop a generic ontology design pattern for observation-based data on the Semantic Web. The core classes and relationships forming the pattern are discussed in detail and are aligned to the DOLCE foundational ontology to improve semantic interoperability and clarify the underlying ontological commitments.(More)
The Geosciences and Geography are not just yet another application area for semantic technologies. The vast heterogeneity of the involved disciplines ranging from the natural sciences to the social sciences introduces new challenges in terms of interoperability. Moreover, the inherent spatial and temporal information components also require distinct(More)
Feature types play a crucial role in understanding and analyzing geographic information. Usually, these types are defined, standardized, and controlled by domain experts and cover geographic features on the mesoscale level, e.g., populated places, forests, or lakes. While feature types also underlie most Location-Based Services (LBS), assigning a consistent(More)
The vision of a Digital Earth calls for more dynamic information systems , new sources of information, and stronger capabilities for their integration. Sensor networks have been identified as a major information source for the Digital Earth, while Semantic Web technologies have been proposed to facilitate integration.. So far, sensor data is stored and(More)
In this paper we take a fresh look at the problem of information quality for user contributed content. We assert that the traditional quality criteria for assessing the quality of geographic information are difficult to apply to Volunteered Geographic Information. The notion of informational trust is introduced and linked to the established notion of(More)
The Digital Earth [13] aims at developing a digital representation of the planet. It is motivated by the need for integrating and interlinking vast geo-referenced, multi-thematic, and multi-perspective knowledge archives that cut through domain boundaries. Complex scientific questions cannot be answered from within one domain alone but span over multiple(More)
Traditional gazetteers are built and maintained by authoritative mapping agencies. In the age of Big Data, it is possible to construct gazetteers in a data-driven approach by mining rich volunteered geographic information (VGI) from the Web. In this research, we build a scalable distributed platform and a high-performance geoprocessing workflow based on the(More)
With the increasing amount of geographic information available on the Inter-net, searching, browsing, and organizing such information has become a major challenge within the field of Geographic Information Science (GIScience). As all information is ultimately for and from human beings, the methodologies applied to retrieve and organize this information(More)