Publications

Specification and Implementation of Mapping Rule Visualization and Editing: MapVOWL and the RMLEditor

by Pieter Heyvaert, Anastasia Dimou, Tom Seymoens, Erik Mannens, Dimitri Schuurman, Aron-Levi Herregodts, Ben De Meester, Ruben Verborgh,
Published in Journal of Web Semantics.
Keywords: visualization,RML,rules,research,Linked Data,

Visual tools are implemented to help users in defining how to generate Linked Data from raw data. This is possible thanks to mapping languages which enable detaching mapping rules from the implementation that executes them. However, no thorough research has been conducted so far on how to visualize such mapping rules, especially if they become larg…


Supporting sustainable publishing and consuming of live Linked Time Series Streams

by Pieter Colpaert, Julián Rojas Meléndez, Gayane Sedrakyan, Ruben Verborgh,
Published in Proceedings of the 15th ESWC: Posters and Demos.
Keywords: World Wide Web,Web,

The road to publishing public streaming data on the Web is paved with trade-offs that determine its viability. The cost of unrestricted query answering on top of data streams, may not be affordable for all data publishers. Therefore, public streams needs to be funded in a sustainable fashion to remain online. In this paper we introduce an overview …


Declarative Rules for Linked Data Generation at your Fingertips!

by Pieter Heyvaert, Anastasia Dimou, Ben De Meester, Ruben Verborgh,
Published in Proceedings of the 15th ESWC: Posters and Demos.
Keywords: R2RML,RML,annotation,rules,Linked Data,

Linked Data is often generated based on a set of declarative rules using languages such as R2RML and RML. These languages are built with machine-processability in mind. It is thus not always straightforward for users to define or understand rules written in these languages, preventing them from applying the desired annotations to the data sources. …


SeGoFlow: A Semantic Governance Workflow Tool

by Sven Lieber, Anastasia Dimou, Ruben Verborgh,
Published in Proceedings of the 15th ESWC: Posters and Demos.
Keywords: reuse,SPARQL,research,

Data management increasingly demands transparency with respect to data processing. Various stakeholders need information tailored to their needs, e.g. data management plans (DMP) for funding agencies or privacy policies for the public. DMPs and privacy policies are just two examples of documents describing aspects of data processing. Dedicated tool…


RESTdesc—A Functionality-Centered Approach to Semantic Service Description and Composition

by Thomas Steiner, Sam Coppens, Rik Van de Walle, Joaquim Gabarró Vallés, Erik Mannens, Davy Van Deursen, Ruben Verborgh,
Published in The Semantic Web: ESWC 2012 Satellite Events.
Keywords: RESTdesc,REST,World Wide Web,Web,

If we want automated agents to consume the Web, they need to understand what a certain service does and how it relates to other services and data. The shortcoming of existing service description paradigms is their focus on technical aspects instead of the functional aspect—what task does a service perform, and is this a match for my needs? This pap…


Linked Data and Linked APIs: Similarities, Differences, and Challenges

by Thomas Steiner, Rik Van de Walle, Joaquim Gabarró Vallés, Ruben Verborgh,
Published in The Semantic Web: ESWC 2012 Satellite Events.
Keywords: RESTdesc,hypermedia,REST,Linked Data,World Wide Web,Web,

In an often retweeted Twitter post, entrepreneur and software architect Inge Henriksen described the relation of Web 1.0 to Web 3.0 as: “Web 1.0 connected humans with machines. Web 2.0 connected humans with humans. Web 3.0 connects machines with machines.” On the one hand, an incredible amount of valuable data is described by billions of triples, m…


PREMIS OWL

by Tom Creighton, Sébastien Peyrard, Sam Coppens, Rik Van de Walle, Rebecca Guenther, Kevin Ford, Erik Mannens, Ruben Verborgh,
Published in International Journal on Digital Libraries.
Keywords: archiving,provenance,metadata,World Wide Web,Web,

In this article, we present PREMIS OWL. This is a semantic formalisation of the PREMIS 2.2 data dictionary of the Library of Congress. PREMIS 2.2 are metadata implementation guidelines for digitally archiving information for the long term. Nowadays, the need for digital preservation is growing. A lot of the digital information produced merely a dec…


Web-scale Provenance Reconstruction of Implicit Information Diffusion on Social Media

by Sven Lieber, Tom De Nies, Peter Fischer, Io Taxidou, Ruben Verborgh,
Published in Distributed and Parallel Databases.
Keywords: information diffusion,publication,provenance,social media,research,Facebook,World Wide Web,Web,

Fast, massive, and viral data diffused on social media affects a large share of the online population, and thus, the (prospective) information diffusion mechanisms behind it are of great interest to researchers. The (retrospective) provenance of such data is equally important because it contributes to the understanding of the relevance and trustwor…


Enabling context-aware multimedia annotation by a novel generic semantic problem-solving platform

by Rik Van de Walle, Erik Mannens, Davy Van Deursen, Chris Poppe, Ruben Verborgh,
Published in Multimedia Tools and Applications.
Keywords: annotation,Web services,Web service,metadata,Semantic Web,World Wide Web,Web,

Automatic generation of metadata, facilitating the retrieval of multimedia items, potentially saves large amounts of manual work. However, the high specialization degree of feature extraction algorithms makes them unaware of the context they operate in, which contains valuable and often necessary information. In this paper, we show how Semantic Web…


Representing Dockerfiles in RDF

by Pieter Heyvaert, Riccardo Tommasini, Erik Mannens, Emanuele Della Valle, Ben De Meester, Ruben Verborgh,
Published in Proceedings of the 16th International Semantic Web Conference: Posters and Demos.
Keywords: interoperability,research,Linked Data,RDF,

Containers – lightweight, stand-alone software executables – are everywhere. Industries exploit container managers to orchestrate complex cloud infrastructures and researchers in academia use them to foster reproducibility of computational experiments. Among existing solutions, Docker is the de facto standard in the container industry. In this pape…


Querying Dynamic Datasources with Continuously Mapped Sensor Data

by Ruben Taelman, Pieter Heyvaert, Erik Mannens, Ruben Verborgh,
Published in Proceedings of the 15th International Semantic Web Conference: Posters and Demos.
Keywords: publication,Linked Data,RDF,World Wide Web,Web,

The world contains a large amount of sensors that produce new data at a high frequency. It is currently very hard to find public services that expose these measurements as dynamic Linked Data. We investigate how sensor data can be published continuously on the Web at a low cost. This paper describes how the publication of various sensor data source…


Semi-Automatic Example-Driven Linked Data Mapping Creation

by Pieter Heyvaert, Anastasia Dimou, Erik Mannens, Ruben Verborgh,
Published in Proceedings of the 5th International Workshop on Linked Data for Information Extraction.
Keywords: RML,rules,Linked Data,

Linked Data can be generated by applying mapping rules on existing (semi-)structured data. The manual creation of these rules involves a costly process for users. Therefore, (semi-)automatic approaches have been developed to assist users. Although, they provide promising results, in use cases where examples of the desired Linked Data are available …


Data Analysis of Hierarchical Data for RDF Term Identification

by Pieter Heyvaert, Anastasia Dimou, Erik Mannens, Ruben Verborgh,
Published in Proceedings of the Joint International Semantic Technology Conference.
Keywords: Linked Data,RDF,

Generating Linked Data based on existing data sources requires the modeling of their information structure. This modeling needs the identification of potential entities, their attributes and the relationships between them and among entities. For databases this identification is not required, because a data schema is always available. However, for o…


Linked Sensor Data Generation using Queryable RML Mappings

by Ruben Taelman, Pieter Heyvaert, Erik Mannens, Ruben Verborgh,
Published in Proceedings of the 15th International Semantic Web Conference: Posters and Demos.
Keywords: RML,interoperability,communication,reuse,Triple Pattern Fragments,research,Linked Data,RDF,

As the amount of generated sensor data is increasing, semantic interoperability becomes an important aspect in order to support efficient data distribution and communication. Therefore, the integration and fusion of (sensor) data is important, as this data is coming from different data sources and might be in different formats. Furthermore, reusabl…


Towards Approaches for Generating RDF Mapping Definitions

by Pieter Heyvaert, Anastasia Dimou, Rik Van de Walle, Erik Mannens, Ruben Verborgh,
Published in Proceedings of the 14th International Semantic Web Conference: Posters and Demos.
Keywords: rules,Linked Data,Semantic Web,RDF,World Wide Web,Web,

Obtaining Linked Data by modeling domain-level knowledge derived from input data is not straightforward for data publishers, especially if they are not Semantic Web experts. Developing user interfaces that support domain experts to semantically annotate their data became feasible, as the mapping rules were abstracted from their execution. However, …


Towards a Uniform User Interface for Editing Mapping Definitions

by Pieter Heyvaert, Anastasia Dimou, Rik Van de Walle, Erik Mannens, Ruben Verborgh,
Published in Proceedings of the 4th Workshop on Intelligent Exploration of Semantic Data.
Keywords: RML,Linked Data,Semantic Web,RDF,World Wide Web,Web,

Modeling domain knowledge as Linked Data is not straightforward for data publishers, because they are domain experts and not Semantic Web specialists. Most approaches that map data to its RDF representation still require users to have knowledge of the underlying implementations, as the mapping definitions remained, so far, tight to their execution.…


What Factors Influence the Design of a Linked Data Generation Algorithm?

by Pieter Heyvaert, Anastasia Dimou, Ben De Meester, Ruben Verborgh,
Published in Proceedings of the 11th Workshop on Linked Data on the Web.
Keywords: Linked Data generation,Linked Data,

Generating Linked Data remains a complicated and intensive engineering process. While different factors determine how a Linked Data generation algorithm is designed, potential alternatives for each factor are currently not considered when designing the tools’ underlying algorithms. Certain design patterns are frequently applied across different too…


Towards an Interface for User-Friendly Linked Data Generation Administration

by Pieter Heyvaert, Anastasia Dimou, Wouter Maroy, Laurens De Graeve, Erik Mannens, Ruben Verborgh,
Published in Proceedings of the 15th International Semantic Web Conference: Posters and Demos.
Keywords: RML,Linked Data generation,publication,reuse,Linked Data,Semantic Web,World Wide Web,Web,

Linked Data generation and publication remain challenging and complicated, in particular for data owners who are not Semantic Web experts or tech-savvy. The situation deteriorates when data from multiple heterogeneous sources, accessed via different interfaces, is integrated, and the Linked Data generation is a long-lasting activity repeated period…


Towards a Uniform User Interface for Editing Data Shapes

by Pieter Heyvaert, Anastasia Dimou, Ben De Meester, Ruben Verborgh,
Published in Proceedings of the 4th International Workshop on Visualization and Interaction for Ontologies and Linked Data.
Keywords: Semantic Web,RDF,World Wide Web,Web,

Data quality is an important factor for the success of the envisaged Semantic Web. As machines are inherently intolerant at the interpretation of unexpected input, low quality data produces low quality results. Recently, constraint languages such as SHACL were proposed to assess the quality of data graphs, decoupled from the use case and the implem…


RDF Graph Validation Using Rule-Based Reasoning

by Pieter Heyvaert, Anastasia Dimou, Dörthe Arndt, Ben De Meester, Ruben Verborgh,
Published in Semantic Web Journal.
Keywords: validation,proof,reasoning,research,Semantic Web,RDF,World Wide Web,Web,

The correct functioning of Semantic Web applications requires that given RDF graphs adhere to an expected shape. This shape depends on the RDF graph and the application’s supported entailments of that graph. During validation, RDF graphs are assessed against sets of constraints, and found violations help refining the RDF graphs. However, existing v…


Mapping languages: analysis of comparative characteristics

by Pieter Heyvaert, Anastasia Dimou, Ben De Meester, Ruben Verborgh,
Published in Proceedings of First Knowledge Graph Building Workshop.
Keywords: RDF,

RDF generation processes are becoming more interoperable, reusable, and maintainable due to the increased usage of mapping languages: languages used to describe how to generate an RDF graph from (semi-)structured data. This leads to a rise of new mapping languages, each with different characteristics. However, it is not clear which mapping language…


Rule-driven inconsistency resolution for knowledge graph generation

by Pieter Heyvaert, Anastasia Dimou, Ben De Meester, Ruben Verborgh,
Published in Semantic Web Journal.
Keywords: annotation,rules,

Knowledge graphs, which contain annotated descriptions of entities and their interrelations, are often generated using rules that apply semantic annotations to certain data sources. (Re)using ontology terms without adhering to the axioms defined by their ontologies results in inconsistencies in these graphs, affecting their quality. Methods and too…


Using EPUB 3 and the Open Web Platform for Enhanced Presentation and Machine-Understandable Metadata for Digital Comics

by Pieter Heyvaert, Wesley De Neve, Tom De Nies, Rik Van de Walle, Joachim Van Herwegen, Erik Mannens, Miel Vander Sande, Ruben Verborgh,
Published in Proceedings of the 19th International Conference on Electronic Publishing.
Keywords: JavaScript,metadata,World Wide Web,Web,

Various methods are needed to extract information from current (digital) comics. Furthermore, the use of different (proprietary) formats by comic distribution platforms causes an overhead for authors. To overcome these issues, we propose a solution that makes use of the EPUB 3 specification, additionally leveraging the Open Web Platform to support …


Parallel RDF generation from heterogeneous big data

by Pieter Heyvaert, Anastasia Dimou, Wouter Maroy, Gerald Haesendonck, Ruben Verborgh,
Published in Proceedings of the International Workshop on Semantic Big Data.
Keywords: RML,RDF,

To unlock the value of increasingly available data in high volumes, we need flexible ways to integrate data across different sources. While semantic integration can be provided through RDF generation, current generators insufficiently scale in terms of volume. Generators are limited by memory constraints. Therefore, we developed the RMLStreamer, a …


Modeling, Generating, and Publishing Knowledge as Linked Data

by Ruben Taelman, Pieter Heyvaert, Anastasia Dimou, Ruben Verborgh,
Published in Proceedings of the 20th International Conference on Knowledge Engineering and Knowledge Management.
Keywords: Linked Data publication,Linked Data Fragments,XML,RML,Linked Data generation,Web API,Triple Pattern Fragments,Linked Data,Semantic Web,JSON,World Wide Web,Web,

The process of extracting, structuring, and organizing knowledge from one or multiple data sources and preparing it for the Semantic Web requires a dedicated class of systems. They enable processing large and originally heterogeneous data sources and capturing new knowledge. Offering existing data as Linked Data increases its shareability, extensib…


Graph-Based Editing of Linked Data Mappings using the RMLEditor

by Pieter Heyvaert, Anastasia Dimou, Rik Van de Walle, Erik Mannens, Ruben Verborgh,
Published in Proceedings of the 13th Extended Semantic Web Conference: Posters and Demos.
Keywords: RML,Linked Data generation,Linked Data,Semantic Web,World Wide Web,Web,

Linked Data is in many cases generated from (semi-)structured data. This generation is supported by several tools, a number of which use a mapping language to facilitate the Linked Data generation. However, knowledge of this language and other used technologies is required to use the tools, limiting their adoption by non-Semantic Web experts. We de…


RMLEditor: A Graph-based Mapping Editor for Linked Data Mappings

by Pieter Heyvaert, Anastasia Dimou, Rik Van de Walle, Erik Mannens, Dimitri Schuurman, Aron-Levi Herregodts, Ruben Verborgh,
Published in The Semantic Web: Latest Advances and New Domains (ESWC 2016).
Keywords: RML,research,Linked Data,RDF,

Although several tools have been implemented to generate Linked Data from raw data, users still need to be aware of the underlying technologies and Linked Data principles to use them. Mapping languages enable to detach the mapping definitions from the implementation that executes them. However, no thorough research has been conducted on how to faci…


Merging and Enriching DCAT Feeds to Improve Discoverability of Datasets

by Pieter Heyvaert, Pieter Colpaert, Rik Van de Walle, Erik Mannens, Ruben Verborgh,
Published in Proceedings of the 12th Extended Semantic Web Conference: Posters and Demos.
Keywords: DBpedia,Triple Pattern Fragments,SPARQL,World Wide Web,Web,

Data Catalog Vocabulary (DCAT) is a W3C specification to describe datasets published on the Web. However, these catalogs are not easily discoverable based on a user’s needs. In this paper, we introduce the Node.js module "dcat-merger" which allows a user agent to download and semantically merge different DCAT feeds from the Web into one DCAT feed, …


Semantically Annotating CEUR-WS Workshop Proceedings with RML

by Pieter Heyvaert, Anastasia Dimou, Rik Van de Walle, Erik Mannens, Ruben Verborgh,
Published in Proceedings of the 12th Extended Semantic Web Conference: Semantic Publishing Challenge.
Keywords: RML,SPARQL,RDF,

In this paper, we present our solution for the first task of the second edition of the Semantic Publishing Challenge. The task requires extracting and semantically annotating information regarding CEUR-WS workshops, their chairs and conference affiliations, as well as their papers and their authors, from a set of html-encoded workshop proceedings v…


Linked Data-enabled Gamification in EPUB 3 for Educational Digital Textbooks

by Pieter Heyvaert, Rik Van de Walle, Erik Mannens, Ruben Verborgh,
Published in Proceedings of the 10th European Conference on Technology Enhanced Learning.
Keywords: JavaScript,Linked Data,

Interest in eLearning environments is constantly increasing, as well as in digital textbooks and gamification. The advantages of gamification in the context of education have been proven. However, gamified educational material, such as digital textbooks and digital systems, are scarce. As an answer to the need for such material, the framework GEL (…


Conformance Test Cases for the RDF Mapping Language (RML)

by Pieter Heyvaert, Anastasia Dimou, Oscar Corcho, Freddy Priyatna, Erik Mannens, David Chaves-Fraga, Ruben Verborgh,
Published in Proceedings of the 1st Iberoamerican Knowledge Graphs and Semantic Web Conference.
Keywords: CARML,CSV,XML,R2RML,RMLMapper,RML,annotation,rules,programming,RDF,JSON,

Knowledge graphs are often generated using rules that apply semantic annotations to data sources. Software tools then execute these rules and generate or virtualize the corresponding RDF-based knowledge graph. RML is an extension of the W3C-recommended R2RML language, extending support from relational databases to other data sources, such as data i…