Kim Ahlstrøm (Aalborg University) will talk in the LiU Semantic Web Seminars Series

KimAhlstromOn February 7 (Tuesday), Kim Ahlstrøm of Aalborg University will give a talk in our series of Semantic Web seminars. The title of his talk is:

Towards Answering Provenance-Enabled SPARQL Queries over RDF Data Cubes

Abstract: The SPARQL 1.1 standard has made it possible to formulate analytical queries in SPARQL. While some approaches have become available for processing analytical queries on RDF data cubes, little attention has been paid to answering provenance-enabled queries over such data. Yet, considering provenance is a prerequisite to being able to validate if a query result is trustworthy. The main challenge for existing triple stores is the way provenance can be encoded in standard triple stores based on context values (named graphs). In this talk, I will present shortcomings in existing techniques, and we propose an index to handle the high number of context values that provenance encoding typically entails. Our experimental results using the Star Schema Benchmark show the feasibility and scalability of our index and query evaluation strategies.

Time and date: 3.15pm, February 7, 2017

Location: Campus Valla, Building B, Room “Charles Babbage”

Marjan Alirezaie (Örebro University) will talk in the LiU Semantic Web Seminars Series

PhotoMarjanAlirezaieOn Tuesday next week, January 24, Marjan Alirezaie of Örebro University will give a talk in our series of Semantic Web seminars. The title of her talk is:

Recent Developments in Bridging the Semantic Gap Problem

Abstract: In this talk, I will present a summary of my PhD thesis which is about bridging the semantic gap between sensor data and ontological knowledge. The focus will be on the recent developments in heterogeneous knowledge integration as a solution for the semantic gap issue. I will also introduce the two research projects: Semantic Robot and E-care@home, with the goal of addressing the knowledge integration problem. In Semantic Robot, we are aiming to provide a semantic layer to a 3D topographic map and making the objects in the 3D map reasoning ready for different purposes such as querying and navigation. Likewise, in Ecare@home which is a Swedish interdisciplinary distributed research environment, our focus is on the development of methods that provide interpretation of the heterogeneous data coming from different types of sensors in conjunction with both medical and environmental knowledge in order to provide e-services for the elderly residing in their homes.

Time and date: 3.15pm, January 24, 2017

Location: Campus Valla, Building B, Room “Alan Turing”

Hannes Ebner (MetaSolutions AB) will talk in the LiU Semantic Web Seminars Series

HannesEbnerOn Monday next week, October 31, Hannes Ebner of MetaSolutions AB will give a talk in our series of Semantic Web seminars. The title of his talk is:

From Research to Business – Enabling Agile Information Management with Linked Data

Abstract: MetaSolutions was founded in 2011 as a spin-off from research on Web Architecture and Linked Data. Even today the Linked Data technology stack builds the foundation of the company’s product platform that allows organisations to manage their information in a more agile way. Hannes Ebner, one of the two founders, will talk about how a product emerged from research prototypes, which common business problems the company tackles, and how the application of Linked Data became a competitive advantage.

Time and date: 11am, October 31, 2016

Location: Campus Valla, Building B, Room “Charles Babbage”

LiU Semantic Web research at ODBASE 2016

ODBASE_smallWe have two research papers in the 15th Int. Conference on Ontologies, Databases, and Applications of Semantics (ODBASE 2016) to take place this week in Rhodes, Greece. These papers are:

  • Bindings-Restricted Triple Pattern Fragments” by our Olaf Hartig and Carlos Buil-Aranda from the Universidad Tecnica Federico Santa Maria, Chile–read an extended preprint of this paper and check out the Web page for the paper.
  • Scheduling Refresh Queries for Keeping Results from a SPARQL Endpoint Up-to-Date” by Magnus Knuth (Hasso Plattner Institute, Potsdam, Germany), Olaf Hartig, and Harald Sack (Hasso Plattner Institute)–check out the preprint of this paper or the extended version which provides more details about the characteristics of the experimental data, and there is also a Web page with the experimental data.

Olaf Hartig will attend the conference and present the first of these papers. He will be happy to talk to you if you also happen to be in the conference.

Best Poster Award at ISWC 2016

ISWC2016BestPosterWe are very happy to announce that Olaf Hartig has won the Peoples’ Choice Best Poster Award at the 15th International Semantic Web Conference (ISWC 2016), which is the main conference in our field. The research presented on the poster is joint work with Carlos Buil-Aranda from the Universidad Tecnica Federico Santa Maria, Chile.

The poster is titled “Reducing the Network Load of Triple Pattern Fragments by Supporting Bind Joins.” You may want to read the poster paper, and there is also a Web page for this work. Additionally, a full research paper about this work (title: “Bindings-Restricted Triple Pattern Fragments“) will be published in the proceedings of the ODBASE 2016 conference; an extended pre-print of this paper is already available.