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New Generation Sensor Web Enablement
The recent developments of the new generation of the Sensor Web Enablement specification framework are illustrated and related to other emerging concepts such as the Web of Things and point out challenges and resulting future work topics for research on Sensor Web enablement. Expand
Semantic interoperability of distributed geo-services
The research presented in the thesis provides solutions for the computer-aided integration of distributed heterogeneous geo-information and geo-services, based on their semantics, by formally describing the geoservices with ontological concepts and reasoning with them in Description Logics. Expand
Integrating Semantic and Syntactic Descriptions to Chain Geographic Services
This method facilitates the use of XML-based service description languages to build a geoservice-reuse architecture based on common ontologies and shared service descriptions. Expand
Enhancing Geo-Service Chaining through Deep Service Descriptions
We demonstrate the integrated use of semantic and syntactic service descriptions, called deep service descriptions, for service chaining by combining two prototypes: one that deals with geoserviceExpand
Finding and sharing GIS methods based on the questions they answer
This article systematically investigates the analytic questions that lie behind a range of common GIS tools, and proposes a semantic framework to match analytic questions and tools that are capable of answering them and defines a tractable subset of SPARQL, the query language of the Semantic Web. Expand
Exploratory querying of SPARQL endpoints in space and time
This article proposes design principles for SPEX (Spatio-temporal content explorer), a tool which helps people unfamiliar with the content of SPARQL endpoints or their syntax to explore the latter in space and time, and proposes a way to deal with challenges by interactive visual query construction. Expand
Conceptualization of place via spatial clustering and co-occurrence analysis
This paper develops in this paper an approach based on the analyses of tags and geo-tags for the exploration and characterization of the implicit localities in collections of user photos to explore the meanings given by users about the places in their photo collections. Expand
Not just a tool. Taking context into account in the development of a mobile App for rural water supply in Tanzania
The 'eGovernance' hype around the potential of mobile phone and geoweb technologies for enhancing 'good governance' is soaring. In East Africa, the extensive use of mobile telephony adds to theExpand
Modeling aggregated expertise of user contributions to assess the credibility of OpenStreetMap features
This study proposes an intrinsic measure of quality by developing the concept of aggregated expertise based on the characteristics of a feature's contributors and operationalizes this concept and examines its feasibility through a case study using OpenStreetMap. Expand
Semantic and syntactic service descriptions at work in geo service chaining
SUMMARY In this paper we demonstrate the integrated use of semantic and syntactic service descriptions for service chaining, by combining a prototype that deals with service discovery and abstractExpand