Third International Workshop on Semantics and the Web for Transport

Co-located with the SEMANTiCS Conference 2021

Amsterdam, Netherlands - 6 September 2021

Read the proceedings

Sem4Tra Call for Papers

Smart Cities could not be realized without envisioning a change towards the Mobility-as-a-Service (MaaS) paradigm for integrated and intelligent transportation. MaaS improves every aspect of transportation from ticketing to navigation, from traffic to parking management and from car/bike sharing to door-to-door travel. However, to make MaaS a reality, challenges in data integration must be addressed. The development of multimodal travel information, planning and booking services, and the interoperability between business applications are currently limited due to the fragmentation and incompatibility of interchange formats and protocols both within and across transport sectors. This workshop seeks to advance MaaS through Semantic Web, Linked Data and Knowledge Graph techniques. In-scope are methods to query and reason over integrated data on the web that can help an end-user to plan and book a trip from A to B. We target researchers and practitioners who are contributing to the transformation of the transportation sector by proposing new solutions based on semantic techniques and technologies, to realize MaaS objectives. The workshop is an opportunity for disseminating and discussing use cases and studies showing the application of semantic and web technologies in the transport domain to tackle the aforementioned challenges.


  • Decentralized data management
  • Query languages and methods for a Web of Transport Data
  • Creating automated alignments between datasets using the various specifications
  • Recommendations for mobility specification builders to raise interoperability between specifications
  • Alignments with existing or upcoming general-purpose Web API specifications such as W3C Web payments or Solid
  • Interfaces between enterprise data and the Semantic Web
  • The exploitation of Transport Data on the Web
  • Challenges and opportunities for route planning and ticketing
  • Personalized route planning taking into account data stored on your client or personal data space
  • Anonymization in the mobility space for data sharing
  • Benchmarking of Web Infrastructure
  • Comparing ticketing API architectures
  • Comparing route planning API architectures
  • Publishing and querying planned transport data and their live updates on the Web
  • Knowledge Graphs and Ontologies in the transportation domain
  • Aligning regional vocabularies with international reference domain models such as Transmodel, NeTEx, SIRI or DATEXII
  • Reusing existing linked datasets, such as Geonames, OpenStreetMap or Wikidata, for MaaS use cases
  • Bridging the gap with non-RDF specifications such as MobilityDataSpecification, General Transit Feed Specification, General Bike Feed Specification, TOMP API or MaaS API
  • Building a Knowledge Graph of the transportation domain by integration and conversion of heterogeneous data sources (e.g., National Access Points or local sources)
  • Semantic technology applications and datasets on smart mobility

Authors Guideline


Authors can choose the best way to express their work, such as HTML or PDF. However, a LNCS-like layout should be provided.


  • Long research/experience papers (10-12 pages)
  • Short research papers (4-6 pages)
  • Position papers (4-6 pages)
  • System/demo papers (4-6 pages)
  • Abstract from journal papers (2-4 pages)
  • 5 minutes lightning talk for project or idea(1 page max)

Review and Publication

Please, share your contribution before the deadline through the OpenReview platform. The accepted contributions will be published in the proceedings of the workshop with CEUR. Each accepted paper needs to be presented by one of the authors at the workshop.


Schedule (CET TIMES)

Session 1 (09:00 - 10:30): Mobility as a Service on the Web

  • Welcome to the 3rd Edition of the Sem4Tra Workshop.
  • Keynote: Transmodel in RDF? by Kasia Bouree, expert within the European project Data4PT. Slides
  • Third-party payment specification for Mobility as a Service. Brecht Van de Vyvere, Tim Asperges, Pieter Colpaert, Ruben Verborgh. Paper - Slides
  • Towards a More Informed Multimodal Travel Shopping. Mario Scrocca, Marco Comerio, Damiano Scandolari, Irene Celino. Paper - Slides
  • Linked MaaS: a vision for leveraging Semantic Web Technologies for Mobility as a Service. Shams Ghazy, Jing Ying Wong, Pieter Colpaert, Yu Hoe Tang, Andy Chan. Paper - Slides
  • Q&A

15 minutes - break

Session 2 (10:45 - 11:45): Semantic Data Management for Transport

  • Journal paper presentation: Publishing planned, live and historical public transport data on the Web with the Linked Connections framework. Julian Rojas, Pieter Colpaert. Paper - Slides
  • Semantic Conversion of Transport Data Adopting Declarative Mappings: an Evaluation of Performance and Scalability. Mario Scrocca, Alessio Carenini, Marco Comerio, Irene Celino. Paper - Slides
  • On the Visualization of Semantic-based Mappings. Nicolò Oreste Pinciroli Vago, Mario Sacaj, Mersedeh Sadeghi, Safia Kalwar, Andrea vogelsang, Matteo G. Rossi. Paper - Slides
  • Enabling Cross-Border Travel Offers Through National Access Point Federation via Metadata Harmonisation. Alessio Carenini, Andrea Fiano, Mario Scrocca, Marco Comerio, Irene Celino. Paper - Slides
  • Q&A

Important dates

20 July, 2021

Submission papers

Submit your paper

30 July, 2021


The notification and reviews from our Program Committee will be available.

25 August, 2021

Submission camera ready

Time to have your paper ready for being published. All the accepted paper will be published in the proceedings.

6 September, 2021


Keynote, papers presentations, demo jam and a lot of discussion. Remember! If your contribution is accepted, it needs to be presented by one of the authors at the event.


David Chaves Fraga

Postdoctoral Researcher, OEG - UPM

Marco Comerio

Senior Researcher, CEFRIEL

Mario Scrocca

Assistant Researcher, CEFRIEL

Mersedeh Sadeghi

Senior Researcher, University of Cologne

Pieter Colpaert

Senior Researcher, imec - IDLab UGent

Program Committee

  • Alessio Carenini, CEFRIEL
  • Edna Ruckhaus, Universidad Politécnica de Madrid
  • Irene Celino, CEFRIEL
  • Julián Rojas, imec - IDLab UGent
  • Matteo Giovanni Rossi, Politecnico di Milano
  • Oscar Corcho, Universidad Politécnica de Madrid
  • Ruben Taelman, imec - IDLab UGent
  • Alireza Javadian Sabet, Politecnico di Milano
  • Julián Arenas Guerrero, Universidad Politécnica de Madrid
  • Shams Ghazy, University of Nottingham
  • Marjan Hosseini, University of Connecticut
  • Mahsa Shekari, Politecnico di Milano
  • Umutcan Simsek, STI Innsbruck