Karsten Tolle

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ABSTRACT Metadata are widely used in order to fully exploit information resources available on corporate intranets or the Internet. The Resource Description Framework (RDF) aims at facilitating the creation and exchange of metadata as any other Web data. The growing number of available information resources and the proliferation of description services in(More)
Real scale Semantic Web applications such as Knowledge Portals and E Marketplaces require the management of voluminous repositories of resource metadata The Resource Description Framework RDF enables the creation and exchange of metadata as any other Web data Although large volumes of RDF descriptions are already appearing su ciently expressive declarative(More)
Metadata are widely used in order to fully exploit information resources available on corporate intranets or the Internet. The Resource Description Framework (RDF) aims at facilitating the creation and exchange of metadata as any other Web data. The growing number of available information resources and the proliferation of description services in various(More)
Building profiles of registered users of a web site, as in case of a portal, is of importance if it goes beyond collecting the obvious information the user is willing to give at the time of registration. The starting point of this work is the assumption that a community of users is registered on a web site and that for each user a profile is built. Such a(More)
The need for descriptive information, i.e., metadata, about Web resources has been recognized in several application contexts (e.g., digital libraries, portals). The Resource Description Framework (RDF) aims at facilitating the creation and exchange of metadata, as directed labeled graphs serialized in XML. In particular, the de nition of schema(More)
We have introduced the concept of non-obvious user profiles (NOPs) to capture the hypothetical interest of Web users. In this paper we present the design principles and rules of our Gugubarra engine, which is a tool to calculate and visualize these non-obvious user profiles
<i>Web portals</i> have a huge importance on today's Internet. Their purpose is to serve as an entry point to information on the Web, by proposing search and classification related services. The usefulness of a Web portal depends directly on the quality of service it offers. This paper presents the SIMAT architecture which exploits a backbone of machines(More)
There exist different ways how to understand and use context information for RDF data. This paper summarizes these different ways and concentrates on the source information. It shows what can be achieved by knowing the source information and will present the RDF-Source related Storage System (RDF-S3). RDF-S3 is an application implementing one way to keep(More)
In this paper, we describe the main barriers for interoperability between different SME's in less developed countries. We explain how we address these barriers by technologies like UBL and approach how to include and support humans into the B2B process using a federated integration approach instead of forcing everything to be done through the system.