Supporting SPARQL Update Queries in RDF-XML Integration

The Web of Data encourages organizations and companies to publish their data according to the Linked Data practices and offer SPARQL endpoints. On the other hand, the dominant standard for information exchange is XML. The SPARQL2XQuery Framework focuses on the automatic translation of SPARQL queries in XQuery expressions in order to access XML data across the Web. In this paper, we outline our ongoing work on supporting update queries in the RDF-XML integration scenario.Comment: 13th International Semantic Web Conference (ISWC '14

Big Data – a step change for SDI?

The globally hyped notion of Big Data has increasingly influenced scientific and technical debates about the handling and management of geospatial information. Accordingly, we see a need to recall what has happened over the past years, to present the recent Big Data landscape from an infrastructural perspective and to outline the major implications for the SDI community. We primarily conclude that it would be too simple and naïve to consider only the technological aspects that are underpinning geospatial (web) services. Instead, we request SDI researchers, engineers, providers and consumers to develop new methodologies and capacities for dealing with (geo)spatial information as part of broader knowledge infrastructures

Querying XML Data with SPARQL

Abstract. SPARQL is today the standard access language for Semantic Web data. In the recent years XML databases have also acquired industrial impor-tance due to the widespread applicability of XML in the Web. In this paper we present a framework that bridges the heterogeneity gap and creates an interop-erable environment where SPARQL queries are used to access XML databases. Our approach assumes that fairly generic mappings between ontology con-structs and XML Schema constructs have been automatically derived or manu-ally specified. The mappings are used to automatically translate SPARQL que-ries to semantically equivalent XQuery queries which are used to access the XML databases. We present the algorithms and the implementation of SPARQL2XQuery framework, which is used for answering SPARQL queries over XML databases

A Conceptual Model for Participants and Activities in Citizen Science Projects

24 pages, 4 figures, 3 tablesInterest in the formal representation of citizen science comes from portals, platforms, and catalogues of citizen science projects; scientists using citizen science data for their research; and funding agencies and governments interested in the impact of citizen science initiatives. Having a common understanding and representation of citizen science projects, their participants, and their outcomes is key to enabling seamless knowledge and data sharing. In this chapter, we provide a conceptual model comprised of the core citizen science concepts with which projects and data can be described in a standardised manner, focusing on the description of the participants and their activities. The conceptual model is the outcome of a working group from the COST Action CA15212 Citizen Science to Promote Creativity, Scientific Literacy, and Innovation throughout Europe, established to improve data standardisation and interoperability in citizen science activities. It utilises past models and contributes to current standardisation efforts, such as the Public Participation in Scientific Research (PPSR) Common Conceptual Model and the Open Geospatial Consortium (OGC) standards. Its design is intended to fulfil the needs of different stakeholders, as illustrated by several case studies which demonstrate the model’s applicabilityPeer reviewe

Support for interoperability between OWL based and XML schema based applications

Summarization: We present in this paper a framework that provides support for interoperability between XML Schema based and OWL based applications. In particular, we describe how the information exchange between such applications is achieved, through the transformations of XML documents to OWL/RDF descriptions and of OWL/RDF descriptions to (parts of) valid XML documents. This functionality is built on top of OWL ontologies that fully capture the semantics of the XML Schemas. These ontologies are the outcome of the application of the XS2OWL mapping model that we have developed on an XML Schema. This way, the work reported here integrates and extends our previous work on the XS2OWL mapping model to take into account, in addition to the transformation of XML Schemas to OWL-DL ontologies, the transformation of XML documents to OWL/RDF descriptions and vice versa.Παρουσιάστηκε στο: In the Proceedings of the 6th International Conference on Web-based Learnin

Ontology-Driven Interoperability for MPEG-7

Research efforts for interoperability support in the multimedia domain are presented here. Interoperability, both at the syntactic and the semantic level, is necessary in the open multimedia consumption environment formed in the Internet today, so that the multimedia content services offered by different vendors may interoperate. Syntactic interoperability support is achieved in the multimedia domain through the adoption of the dominant MPEG-7 standard for multimedia content and service description. Domain knowledge is then integrated, in the form of domain ontologies, in the MPEG-7 constructs, in order to achieve semantic interoperability. Finally, the utilization of the interoperability support in real world applications is discussed.

A multimedia user preference model that supports semantics and its application to MPEG 7/21

Summarization: Semantic interoperability is usually provided in open environments through standards and domain ontologies. The dominant standards for multimedia content and service descriptions are MPEG-7 and MPEG- 21. The MPEG-7 Semantic DS has powerful semantic description capabilities and supports using semantic entities specified in domain ontologies in multimedia content descriptions. However, the MPEG-7/21 Usage Environment allows neither the specification of semantic user preferences nor the exploitation of domain knowledge and MPEG-7 semantic metadata descriptions. In addition, the users cannot explicitly specify, in the hierarchical MPEG-7/21 filtering and search preferences, the boolean operators that should be used during content filtering to combine the hierarchy components. We think these as serious limitations and we propose a hierarchical semantic user preference model that allows for the explicit specification of boolean operators. Then, we present the application of the model in MPEG-7/21 and the model implementation within the DS-MIRF framework.Παρουσιάστηκε στο: In the proceedings of the Multimedia Modelin