@inproceedings{dietzold2008xoperator,
  abstract = {Instant Messaging is in addition to Web and Email the most popular service on the Internet. With xOperator we present a strategy and implementation which deeply integrates Instant Messaging networks with the Semantic Web. The xOperator concept is based on the idea of creating an overlay network of collaborative information agents on top of social IM networks. It can be queried using a controlled and easily extensible language based on AIML templates. Such a deep integration of semantic technologies and Instant Messaging bears a number of advantages and benefits for users when compared to the separated use of Semantic Web technologies and IM, the most important ones being context awareness as well as provenance and trust. We showcase how the xOperator approach naturally facilitates contacts and calendar management as well as access to large scale heterogeneous information sources.},
  added-at = {2008-05-28T14:50:05.000+0200},
  address = {Berlin, Heidelberg},
  author = {Dietzold, Sebastian and Unbehauen, Jörg and Auer, Sören},
  biburl = {http://www.bibsonomy.org/bibtex/2e672f158fc594179cd9fd36f8a135de4/eswc2008},
  booktitle = {Proceedings of the 5th European Semantic Web Conference},
  editor = {Hauswirth, Manfred and Koubarakis, Manolis and Bechhofer, Sean},
  interhash = {170f8929b13305d8621da905ef0a887a},
  intrahash = {e672f158fc594179cd9fd36f8a135de4},
  keywords = {instant agent sparql xmpp rdf messaging agents-application-ontologies},
  month = {June},
  publisher = {Springer Verlag},
  series = {LNCS},
  timestamp = {2008-05-28T14:50:05.000+0200},
  title = {xOperator - Interconnecting the Semantic Web and Instant Messaging Networks},
  url = {http://data.semanticweb.org/conference/eswc/2008/papers/293},
  year = 2008
}

@inproceedings{langegger2008semantic,
  abstract = {In this contribution a system is presented, which provides access to distributed data sources using Semantic Web technology. While it was primarily designed for data sharing and scientific collaboration, it is regarded as a base technology useful for many other Semantic Web applications. The proposed system allows to retrieve data using SPARQL queries, data sources can register and abandon freely, and all RDF Schema or OWL vocabularies can be used to describe their data, as long as they are accessible on the Web. Data heterogeneity is addressed by RDF-wrappers like D2R-Server placed on top of local information systems. A query does not directly refer to actual endpoints, instead it contains graph patterns adhering to a virtual data set. A mediator finally pulls and joins RDF data from different endpoints providing a transparent on-the-fly view to the end-user.  The SPARQL protocol has been defined to enable systematic data access to remote endpoints. However, remote SPARQL queries require the explicit notion of endpoint URIs. The presented system allows users to execute queries without the need to specify target endpoints. Additionally, it is possible to execute join and union operations across different remote endpoints. The optimization of such distributed operations is a key factor concerning the performance of the overall system. Therefore, proven concepts from database research can be applied.},
  added-at = {2008-05-28T14:50:00.000+0200},
  address = {Berlin, Heidelberg},
  author = {Langegger, Andreas and Wöß, Wolfram and Blöchl, Martin},
  biburl = {http://www.bibsonomy.org/bibtex/2fc7f36c61174d07ed9bdb4608c250284/eswc2008},
  booktitle = {Proceedings of the 5th European Semantic Web Conference},
  editor = {Hauswirth, Manfred and Koubarakis, Manolis and Bechhofer, Sean},
  interhash = {7d1e1c709cbbfb8f8f8f7865d7ca1632},
  intrahash = {fc7f36c61174d07ed9bdb4608c250284},
  keywords = {processing data mediator integration distributed sparql query semantic web query-processing-2},
  month = {June},
  publisher = {Springer Verlag},
  series = {LNCS},
  timestamp = {2008-05-28T14:50:00.000+0200},
  title = {A Semantic Web Middleware for Virtual Data Integration on the Web},
  url = {http://data.semanticweb.org/conference/eswc/2008/papers/244},
  year = 2008
}

@inproceedings{quilitz2008querying,
  abstract = {Integrated access to multiple distributed and autonomous RDF data sources is a key challenge for many semantic web applications. As a reaction to this challenge, SPARQL, the current W3C Proposed Recommendation for an RDF query language, supports querying of multiple RDF graphs. However, the current standard does not provide transparent query federation, which makes query formulation hard and lengthy. Furthermore, current implementations of SPARQL load all RDF graphs mentioned in a query to the local machine. This usually incurs a large overhead in network traffic, and sometimes is simply impossible for technical or legal reasons. To overcome these problems we present DARQ, an engine for federated SPARQL queries. DARQ provides transparent query access to multiple SPARQL services, i.e., it gives the user the impression to query one single RDF graph despite the real data being distributed on the web. A service description language enables the query engine to decompose a query into sub-queries, each of which can be answered by an individual service. DARQ also uses query rewriting and cost-based query optimization to speed-up query execution. Experiments show that these optimizations significantly improve query performance even when only a very limited amount of statistical information is available. DARQ is available under GPL License at http://darq.sf.net/.},
  added-at = {2008-05-28T14:49:59.000+0200},
  address = {Berlin, Heidelberg},
  author = {Quilitz, Bastian and Leser, Ulf},
  biburl = {http://www.bibsonomy.org/bibtex/2f4535c0e1abeb4c40bf6e78b91322dfc/eswc2008},
  booktitle = {Proceedings of the 5th European Semantic Web Conference},
  editor = {Hauswirth, Manfred and Koubarakis, Manolis and Bechhofer, Sean},
  interhash = {3e97ddf59556ee09dcae169480a7a651},
  intrahash = {f4535c0e1abeb4c40bf6e78b91322dfc},
  keywords = {processing query queries optimization sparql federated query-processing-2},
  month = {June},
  publisher = {Springer Verlag},
  series = {LNCS},
  timestamp = {2008-05-28T14:49:59.000+0200},
  title = {Querying Distributed RDF Data Sources with SPARQL},
  url = {http://data.semanticweb.org/conference/eswc/2008/papers/168},
  year = 2008
}

@inproceedings{kiefer2008creation,
  abstract = {This research explores our novel method for Semantic Web service matchmaking based on iSPARQL queries, which enable the user to query the Semantic Web with techniques from traditional information retrieval. The strategies for matchmaking which we develop and evaluate in the paper make use of a plethora of similarity measures and combination functions from SimPack -- our library of similarity measures for the use in ontologies. We show how our combination of structured and imprecise querying can be used to perform hybrid Semantic Web service matchmaking in simple and amazingly fast fashion. We analyze our approach thoroughly on a large OWL-S service test collection, and show how our initial strategies can be improved by applying machine learning algorithms such as regression, decision trees, or support vector machines to result in the most effective strategies for matchmaking.},
  added-at = {2008-05-28T14:49:57.000+0200},
  address = {Berlin, Heidelberg},
  author = {Kiefer, Christoph and Bernstein, Abraham},
  biburl = {http://www.bibsonomy.org/bibtex/24058a55f996d8c24ef69c32f3c81ccdd/eswc2008},
  booktitle = {Proceedings of the 5th European Semantic Web Conference},
  editor = {Hauswirth, Manfred and Koubarakis, Manolis and Bechhofer, Sean},
  interhash = {88ebc745190a2df9e0990f15ea2cdda7},
  intrahash = {4058a55f996d8c24ef69c32f3c81ccdd},
  keywords = {retrieval information matchmaking machine learning sparql evaluation query-processing-1},
  month = {June},
  publisher = {Springer Verlag},
  series = {LNCS},
  timestamp = {2008-05-28T14:49:57.000+0200},
  title = {The Creation and Evaluation of iSPARQL Strategies for Matchmaking},
  url = {http://data.semanticweb.org/conference/eswc/2008/papers/133},
  year = 2008
}

@inproceedings{akhtar2008xsparql,
  abstract = {With currently available tools and languages, translating between an existing XML format and RDF is a tedious and error-prone task. The importance of this problem is acknowledged by the W3C GRDDL working group who faces the issue of extracting RDF data out of existing HTML or XML files, as well as by the Web service community around SAWSDL, who need to perform lowering and lifting between RDF data from a semantic client and XML messages for a Web service. However, at the moment, both these groups rely solely on XSLT transformations between RDF/XML and the respective other XML format at hand. In this paper, we propose a more natural approach for such transformations based on merging XQuery and SPARQL into the novel language XSPARQL. We demonstrate that XSPARQL provides concise and intuitive solutions for mapping between XML and RDF in either direction, addressing both the use cases of GRDDL and SAWSDL. We also provide and describe an initial implementation of an XSPARQL engine, available for user evaluation.},
  added-at = {2008-05-28T14:49:56.000+0200},
  address = {Berlin, Heidelberg},
  author = {Akhtar, Waseem and Kopecky, Jacek and Krennwallner, Thomas and Polleres, Axel},
  biburl = {http://www.bibsonomy.org/bibtex/23893fa9e66b3f12d435ce19c253d860b/eswc2008},
  booktitle = {Proceedings of the 5th European Semantic Web Conference},
  editor = {Hauswirth, Manfred and Koubarakis, Manolis and Bechhofer, Sean},
  interhash = {32f21ca6ffe06780f5f900919fc14b22},
  intrahash = {3893fa9e66b3f12d435ce19c253d860b},
  keywords = {xquery lifting sparql lowering grddl query-processing-1},
  month = {June},
  publisher = {Springer Verlag},
  series = {LNCS},
  timestamp = {2008-05-28T14:49:56.000+0200},
  title = {XSPARQL: Traveling between the XML and RDF worlds – and avoiding the XSLT pilgrimage},
  url = {http://data.semanticweb.org/conference/eswc/2008/papers/119},
  year = 2008
}

@inproceedings{zhao2008building,
  abstract = {Images play a vital role in scientific studies. An image repository would become a costly and meaningless data graveyard without descriptive metadata. We adapted EPrints, a conventional repository software system, to create a biological research image repository for a local research group, in order to publish images with structured metadata with a minimum of development effort. However, in its native installation, this repository cannot easily be linked with information from third parties, and the user interface has limited flexibility. We address these two limitations by providing Semantic Web access to the contents of this image repository, causing the image metadata to become programmatically accessible through a SPARQL endpoint and enabling the images and their metadata to be presented in more flexible faceted browsers, jSpace and Exhibit. We show the feasibility of publishing image metadata on the Semantic Web using existing tools, and examine the inadequacies of the Semantic Web browsers in providing effective user interfaces. We highlight the importance of a loosely coupled software framework that provides a lightweight solution and enables us to switch between alternative components.},
  added-at = {2008-05-28T14:49:52.000+0200},
  address = {Berlin, Heidelberg},
  author = {Zhao, Jun and Klyne, Graham and Shotton, David},
  biburl = {http://www.bibsonomy.org/bibtex/2695b9700f725c1ceac87066e69883793/eswc2008},
  booktitle = {Proceedings of the 5th European Semantic Web Conference},
  editor = {Hauswirth, Manfred and Koubarakis, Manolis and Bechhofer, Sean},
  interhash = {d5254dbbf3d4b8119a1fb9404f8bbd95},
  intrahash = {695b9700f725c1ceac87066e69883793},
  keywords = {semantic web images faceted sparql application browsing applications-2},
  month = {June},
  publisher = {Springer Verlag},
  series = {LNCS},
  timestamp = {2008-05-28T14:49:52.000+0200},
  title = {Building a Semantic Web Image Repository for Biological Research Images},
  url = {http://data.semanticweb.org/conference/eswc/2008/papers/37},
  year = 2008
}

@inproceedings{kiefer2008adding,
  abstract = {In machine learning/data mining, people have been exploring how to learn models of relational data for a long time. The rational behind this is that exploiting the rich and complex structure of relational data enables to build better models by taking into account the additional information provided by the links between objects. These links are usually hard to model by traditional propositional learning techniques.  We extend this idea to the Semantic Web. In this paper we introduce a novel approach we call SPARQL-ML to perform data mining for Semantic Web data. Our approach is based on traditional SPARQL and statistical relational learning methods, such as Relational Probability Trees and Relational Bayesian Classifiers.  We analyze our approach thoroughly conducting three sets of experiments on synthetic as well as real-world datasets. Our analytical results show that our approach can be used for any Semantic Web dataset to perform instance-based learning and classification. A comparison to kernel methods used in Support Vector Machines shows that our approach is superior in terms of classification accuracy. Moreover, we show how our approach can be used for Semantic Web service classification and automatic semantic annotation.},
  added-at = {2008-05-28T14:49:52.000+0200},
  address = {Berlin, Heidelberg},
  author = {Kiefer, Christoph and Bernstein, Abraham and Locher, André},
  biburl = {http://www.bibsonomy.org/bibtex/2569e52ad749e5ea312aae2a76dca52d7/eswc2008},
  booktitle = {Proceedings of the 5th European Semantic Web Conference},
  editor = {Hauswirth, Manfred and Koubarakis, Manolis and Bechhofer, Sean},
  interhash = {c091f27b3e3d70203862e2f3a1132928},
  intrahash = {569e52ad749e5ea312aae2a76dca52d7},
  keywords = {sparql data statistical evaluation mining relational learning query-processing-1},
  month = {June},
  publisher = {Springer Verlag},
  series = {LNCS},
  timestamp = {2008-05-28T14:49:52.000+0200},
  title = {Adding Data Mining Support to SPARQL via Statistical Relational Learning Methods},
  url = {http://data.semanticweb.org/conference/eswc/2008/papers/32},
  year = 2008
}

@inproceedings{bolles2008streaming,
  abstract = {A lot of work has been done in the area of data stream processing. Most of the previous approaches regard only relational or XML based streams but do not cover semantic richer RDF based stream elements. In our work, we extend SPARQL, the W3C recommendation for an RDF query language, to process RDF data streams. To describe the semantics of our enhancement, we extended the logical SPARQL algebra for stream processing on the foundation of a temporal relational algebra based on multi sets and provide an algorithm to transform SPARQL queries to the new extended algebra. For each logical algebra operator, we defined executable physical counterparts. To show the feasibility of our approach, we implemented it within our ODYSSEUS framework in the context of wind power plant monitoring.},
  added-at = {2008-05-28T14:49:50.000+0200},
  address = {Berlin, Heidelberg},
  author = {Bolles, Andre and Grawunder, Marco and Jacobi, Jonas},
  biburl = {http://www.bibsonomy.org/bibtex/20164f0b77530f4b038a71c7fa3ad6546/eswc2008},
  booktitle = {Proceedings of the 5th European Semantic Web Conference},
  editor = {Hauswirth, Manfred and Koubarakis, Manolis and Bechhofer, Sean},
  interhash = {4e6f4b1c7b24e0e0172ff3321f6c40fb},
  intrahash = {0164f0b77530f4b038a71c7fa3ad6546},
  keywords = {processing sparql stream rdf query-processing-1},
  month = {June},
  publisher = {Springer Verlag},
  series = {LNCS},
  timestamp = {2008-05-28T14:49:50.000+0200},
  title = {Streaming SPARQL - Extending SPARQL to process data streams},
  url = {http://data.semanticweb.org/conference/eswc/2008/papers/3},
  year = 2008
}