The Semantic Web, especially in the light of the current focus on its nature as a Web of Data, is a data-centric system, and arguably the largest such system in existence. Data is being created, published, exported, imported, used, transformed and re-used, by different parties and for different purposes. Together, these actions form a lifecycle of data on the Semantic Web. Understanding this li...

The rise of the mobile Internet has led to emergence of location-based services, but not to commercial breakthroughs in media applications. We created OUTMedia, a location-sensitive music discovery application to investigate the desirable features of user interface in this context. This paper documents our design efforts and a field study using a functional prototype. We utilized several measur...

Content publishing and distribution often occurs in a costly and inefficient manner via client/server networks. Client/server models exhibit negative network externalities in that each additional user causes additional costs by increasingly congesting the system through the consumption of scarce resources. In an era of increasing demand for and size of content, the traditional client/server mod...

While nowadays there is a plethora of Learning Content Management Systems, the collaborative, communitybased creation of rich e-learning content is still not sufficiently well supported. Few attempts have been made to apply crowd-sourcing and wiki-approaches for the creation of e-learning content. However, the paradigm is only applied to unstructured, textual content and cannot be used in SCORM...