Sofia Angeletou

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Although research on integrating semantics with the Web started almost as soon as the Web was in place, a concrete Semantic Web that is, a large-scale collection of distributed semantic metadata emerged only over the past four to five years. The Semantic Web's embryonic nature is reflected in its existing applications. Most of these applications tend to(More)
Watson is a gateway to the Semantic Web: it collects, analyzes and gives access to ontologies and semantic data available online with the objective of supporting their dynamic exploitation by semantic applications. We report on the analysis of 25 500 ontologies and semantic documents collected by Watson, giving an account about the way semantic technologies(More)
While folksonomies allow tagging of similar resources with a variety of tags, their content retrieval mechanisms are severely hampered by being agnostic to the relations that exist between these tags. To overcome this limitation, several methods have been proposed to find groups of implicitly inter-related tags. We believe that content retrieval can be(More)
Watson is a gateway to the Semantic Web: it collects, analyzes and gives access to ontologies and semantic data available online. Its objective is to support the development of next generation Semantic Web applications that dynamically select, combine and exploit the knowledge published on the Semantic Web. We present the design of Watson, which have been(More)
Understanding and forecasting the health of an online community is of great value to its owners and managers who have vested interests in its longevity and success. Nevertheless, the association between community evolution and the behavioural patterns and trends of its members is not clearly understood, which hinders our ability of making accurate(More)
Online communities provide a useful environment for web users to communicate and interact with other users by sharing their thoughts, ideas and opinions, and for resolving problems and issues. Companies and organisations now host online communities in order to support their products and services. Given this investment such communities are required to remain(More)
As the Semantic Web is gaining momentum, more and more semantic data is available online. The second generation of Semantic Web applications already exploit this phenomenon by relying on this huge amount of semantic content. Looking at the requirements of these applications, we show that there is a need for an efficient access point to the Semantic Web,(More)
The increased availability of online knowledge has led to the design of several algorithms that solve a variety of tasks by harvesting the Semantic Web, i.e., by dynamically selecting and exploring a multitude of online ontologies. Our hypothesis is that the performance of such novel algorithms implicitly provides an insight into the quality of the used(More)
The amount of knowledge published on the Semantic Web – i.e, the number of ontologies and semantic documents available online – is rapidly increasing. Following this evolution, changes appear in the way semantic applications are designed: instead of relying on one, self engineered base of semantic data, these next generation Semantic Web applications [2](More)