Reasoning & Querying – State of the Art

Various query languages for Web and Semantic Web data, both for practical use and as an area of research in the scientific community, have emerged in recent years. At the same time, the broad adoption of the internet where keyword search is used in many applications, e.g. search engines, has familiarized casual users with using keyword queries to retrieve information on the internet. Unlike this easy-to-use querying, traditional query languages require knowledge of the language itself as well as of the data to be queried. Keyword-based query languages for XML and RDF bridge the gap between the two, aiming at enabling simple querying of semi-structured data, which is relevant e.g. in the context of the emerging Semantic Web. This article presents an overview of the field of keyword querying for XML and RDF

SWIP at QALD-3 : results, criticisms and lesson learned

International audienceThis paper presents the results obtained by the SWIP system while participating in the QALD-3 (Question Answering over Linked Data) challenge, co-located with CLEF 2013 (Conference and Labs of the Evaluation Forum). We tackled task 1, multilingual question answering, whose purpose is to interpret natural language questions in order to return the answers contained in a graph knowledge base. We answered queries of both proposed datasets (one concerning DBpedia, the other Musicbrainz) and took into consideration only questions in English. The system SWIP (Semantic Web Interface using Patterns) aims at automatically generating formal queries from user queries expressed in natural language. For this, it relies on the use of query patterns which enable the complex task of interpreting natural language queries. The results obtained on the Musicbrainz dataset (precision = 0,51, recall = 0,51, F-measure = 0,51) are very satisfactory and encouraging. The results on DBpedia (precision = 0,16, recall = 0,15, F-measure = 0,16) are more disappointing. In this paper, we present both the SWIP approach and its implementation. We then present the results of the challenge in more detail and their analysis. Finally we draw some conclusions on the strengths and weaknesses of our approach, and suggest ways to improve its performance

Natural language query interpretation into SPARQL using patterns

International audienceOur purpose is to provide end-users with a means to query ontology based knowledge bases using natural language queries and thus hide the complexity of formulating a query expressed in a graph query language such as SPARQL. The main originality of our approach lies in the use of query patterns. In this article we justify the postulate supporting our work which claims that queries issued by real life end-users are variations of a few typical query families. We also explain how our approach is designed to be adaptable to different user languages. Evaluations on the QALD-3 data set have shown the relevancy of the approach

Social semantic search : a case study on web 2.0 for science

When researchers formulate search queries to find relevant content on the Web, those queries typically consist of keywords that can only be matched in the content or its metadata. The Web of Data extends this functionality by bringing structure and giving well-defined meaning to the content and it enables humans and machines to work together using controlled vocabularies. Due the high degree of mismatches between the structure of the content and the vocabularies in different sources, searching over multiple heterogeneous repositories of structured data is considered challenging. Therefore, the authors present a semantic search engine for researchers facilitating search in research related Linked Data. To facilitate high-precision interactive search, they annotated and interlinked structured research data with ontologies from various repositories in an effective semantic model. Furthermore, the authors' system is adaptive as researchers can synchronize using new social media accounts and efficiently explore new datasets