Overview

This course on Semantic Web Technologies is for a) doctoral students in computer science, as well as for b) participants from the public and private sectors. The main component of the course is an intense week of lectures and hands-on sessions. Additional, doctoral students who are taking the course will have to work on lab assignments, and on a project or a term paper.

The course will be delivered by experienced teachers who are part of the Semantic Web research group of the Department of Computer and Information Science (IDA) at Linköping University.

Goals

After attending the course you should:

• Be able to understand and explain the basic ideas of the Semantic Web, including Linked Data and ontologies, and its related standards (RDF, OWL, SPARQL, ...)
• Be able to understand, retrieve, load in a triple store, query (online or offline) and use existing RDF datasets from the Web
• Be able to use an ontology engineering methodology and ontology engineering tools to design and formalize a high-quality OWL ontology, based on a specific usage scenario (set of requirements)
• Be able to evaluate, align, and repair an OWL ontology, using current methods and tools for ontology alignment, evaluation, and repair
• Be able to understand and to explain how ontologies are typically used in applications
• Be able to build an application based on Semantic Web technologies (e.g., by using RDF data, OWL ontologies, etc.)
• Have a basic idea of the current research topics and open research problems in the field

Tentative Schedule for the Week

The intensive week of lectures and hands-on sessions will take place online in week 43 of 2020 (October 19-23).

The schedule for this week is as follows (note that some things might change slightly as we go along):

• Monday (October 19)
  09:15-09:45 Welcome and introduction (slides)
    5 mins break
  09:50-10:50 Introduction to the Semantic Web vision (Eva) (slides)
    10 mins break
  11:00-12:00 Introduction to RDF (Olaf) (slides)
    lunch break
  13:00-14:00 Introduction to ontologies (Eva) (slides)
  14:00-16:00 Introduction to the RDF query language SPARQL (Olaf) (slides)
  16:00-17:00 Hands-on: SPARQL
• Tuesday (October 20)
  09:30-12:00 Introduction to Description Logics (Patrick) (slides)
    lunch break
  13:00-14:15 RDF triplestores (Olaf) (slides)
  14:15-15:00 Hands-on: triplestores
    10 mins break
  15:10-16:30 Making available RDF data online (Olaf) (slides)
                        Hands-on: RDF publishing (try at home)
    5 mins break
  16:35-17:00 Understanding datasets (Olaf) (slides)
• Wednesday (October 21)
  09:00-10:00 Basic OWL modeling (Eva) (slides)
  10:00-11:00 Hands-on: basic OWL modeling using a tool
    5 mins break
  11:05-11:35 Modeling methodology and requirements management (Eva) (slides)
  11:35-12:00 Hands-on: creating requirements
    lunch break
  13:00-14:15 Hands-on: creating an ontology from given requirements
  14:15-14:30 Introduction to ontology design patterns (ODPs) (Eva) (slides, including also the next item below)
  14:30-14:45 ODP-based modeling methodology
  14:45-15:00 Introduction to the group project
  15:00-17:00 Hands-on: collaborative ontology engineering project
• Thursday (October 22)
  09:30-11:00 Querying RDF data live on the Web (Olaf) (slides)
    15 mins break
  11:15-12:00 PhD student's project ideas
    lunch break
  13:00-15:00 Hands-on: collaborative ontology engineering project continued
  15:00-15:30 Group project wrap-up and discussion of potential solutions and experiences (Eva)
    10 mins break
  15:40-16:40 RDF*/SPARQL* (Olaf) (slides)
    5 mins break
  16:45-17:00 Data quality and data cleaning in RDF (Olaf) (slides)
• Friday (October 23)
  09:30-11:15 Ontology alignment and debugging (Patrick) (slides)
    15 mins break
  11:30-12:00 PhD student's project ideas
    lunch break
  13:00-14:00 Introduction to constraints in RDF (SHACL) (Robin)
    5 mins break
  14:05-14:55 Hands-on: SHACL
    5 mins break
  15:00-15:30 RDF Stream Processing (Robin)
  15:30-16:00 Closing (revisit learning outcomes, etc.)

Instructions and requirements for PhD students

In order for PhD students to receive credits/certificates for attending the course you need to do three things: 1) Actively participate in all the lectures and hands-on sessions during the week, 2) complete a set of assignments (listed below), and 3) select and complete a small project to be presented/suggested during Thursday/Friday sessions and then done after the course week (optional, but needed to receive the full 6 credits of the course).

Assignments to be completed are (no hard deadline, but preferably complete and submit within one week from hands-on date):

• Complete and hand in all the SPARQL queries from Hands-on: SPARQL via e-mail to Olaf
• Complete and hand in all the full-text search SPARQL queries from Hands-on: RDF Triple Stores via e-mail to Olaf
• Hand in solutions to the homework of the description logic lecture and of the ontology alignment and debugging lecture (see slides) via e-mail to Patrick
• Complete and hand in the solution to Hands-on: basic OWL modeling using a tool, send result via e-mail to Eva
• Complete and hand in the solution to Hands-on: creating an ontology from given requirements, send result via e-mail to Eva
• Complete and hand in the solution to at least 2 modules from Hands-on: collaborative group project, and one module that integrates at least 2 other modules, send result via e-mail to Eva. If you do not manage to complete two modules + one integrated module during the session, it is ok to integrate the two modules that you make yourself. Otherwise what you send could be two modules that you created yourself + one integrated module that integrates two modules from other people in the group.
• Complete and send all the SHACL shapes you wrote in the Hands-on: SHACL via e-mail to Robin

For the project after the course, please think about a suitable project during the first few days of the course (if you need feedback, please discuss with the teachers), and sign up for presenting your project idea (either in the Thursday or Friday slot in the schedule) here. Slots are provided on a first-come-first-served basis, so if too many people sign up for one of the days, we will have to move some people to the other day. In the signup form you need to provide a few sentences describing your idea/plan for the project. You can select between these two main categories of projects:

• Reading projects: select a topic from the course, read at least 5 research articles in that area, write a summary of those articles (5-10 pages)
• Practical project: select at technology discussed in the course, apply it on something related to your own PhD project, write a summary of what you did and your experience/evaluation of the technology (5-10 pages) - alternatively: a practical project provided by us

For the project you will be assigned one of the teachers as your point of contact, and although there is no hard deadline you should agree on a submission date, preferably within the next month, with your assigned teacher.

Suggestions for further reading

Further reading on RDF and linked-data topics:

• Allemang, Hendler & Gandon: Semantic Web for the Working Ontologist (3rd edition)
• Tom Heath and Christian Bizer (2011) Linked Data: Evolving the Web into a Global Data Space (1st edition). Synthesis Lectures on the Semantic Web: Theory and Technology, 1:1, 1-136. Morgan & Claypool. Free online version. (Slightly old, but mostly still valid.)
• Doods & Davies (2012) Linked Data Patterns. (Again slightly old, but with some useful insights into practice.)
• See also references in the slidesets for the RDF topics.

Further reading on ontology engineering:

• Ontology tutorial for Protege (older version), using the Pizza ontology as an example.
• Allemang, Hendler & Gandon: Semantic Web for the Working Ontologist (3rd edition)
• Keet: An Introduction to Ontology Engineering
• Hitzler, P., Gangemi, A., Janowicz, K., Krisnadhi, A.A., Presutti, V.: Ontology Engineering with Ontology Design Patterns: Foundations and Applications (Contains for instance a chapter describing the XD methodology)
• Videos from a slightly outdated (10 year old) conference tutorial on the basics of the semantic Web. Many basic concepts still apply, but note that new versions of the standards (e.g. OWL2) has appeared since.
• Lambrix, Completing and Debugging Ontologies: state of the art and challenges
• Some papers on specific topics discussed, or requested by students:
  • Blomqvist, E., Hammar, K., and Presutti, V.: Engineering Ontologies with Patterns - The eXtreme Design Methodology. In: Ontology Engineering with Ontology Design Pattern - Foundations and Applications, IOS Press, 2016.
  • Dudas, M., Lohmann, S., Svatek, V., & Pavlov, D. (2018). Ontology visualization methods and tools: A survey of the state of the art. The Knowledge Engineering Review, 33, E10. doi:10.1017/S0269888918000073
  • This chapters contains quite a few examples of ontologies, and tries to describe different kinds of ontologies based on various dimensions: Roussey C., Pinet F., Kang M.A., Corcho O. (2011) An Introduction to Ontologies and Ontology Engineering. In: Ontologies in Urban Development Projects. Advanced Information and Knowledge Processing, vol 1. Springer, London. https://doi.org/10.1007/978-0-85729-724-2_2
  • Old paper discussing types of ontologies, including the image comparing types of ontologies of different levels of abstraction (c.f. Figure 4). N. Guarino: Formal ontology and information systems. In: N. Guarino (ed.), Formal Ontology in Information Systems. Proceedings of FOIS’98, Trento, Italy, 6-8 June 1998. Amsterdam, IOS Press, pp. 3-15. Extended version of the original paper can be found here.

Further reading on DL:

• Baader, Calvanese, McGuinness, Nardi, Patel-Schneider. The Description Logic Handbook. Cambridge University Press, 2003.
• Donini, Lenzerini, Nardi, Schaerf, Reasoning in description logics. Principles of knowledge representation. CSLI publications. pp 191-236. 1996.
• dl.kr.org

Further reading on SHACL and related topics:

• The W3C SHACL recommendation

Teachers

The course will be organized by the Semantic Web research group of the Department of Computer and Information Science (IDA) at Linköping University. In particular, the course will be delivered by the following experienced teachers of the group who have in-depth expertise in the various topics covered by the course:

• Olaf Hartig is an Associate Professor. He has a broad knowledge on topics related to the management of data and databases. His specific areas of expertise in this context focus on data on the Semantic Web and on graph data, as well as on problems of federated data management in which data is distributed over multiple, autonomous and/or heterogeneous data sources. Regarding these topics, Olaf's interests range from systems-building related research all the way to theoretical foundations. Olaf presented several tutorials at top international conferences in the Semantic Web area including WWW (2010, 2013, 2017) and ISWC (2008, 2009, 2017, 2019), and he was lecturer at the 2011 Indian-Summer School on Linked Data.
• Eva Blomqvist is a Senior Researcher. She has mainly worked on research problems related to ontologies an ontology engineering, and was one of the researchers who initially proposed the notion of ontology design patterns, about 12 years ago. During her PhD she worked on semi-automatic ontology development, so-called ontology learning. Eva has also been actively involved in the development, refinement and evaluation of the eXtreme Design ontology engineering methodology, which was the first agile ontology engineering methodology when it was proposed in 2009. More recently Eva has been involved in several projects applying ontologies in various contexts, e.g. in decision support systems, and also using ontologies and other Semantic Web technologies to perform semantic complex event processing to make sense of streaming data.
• Patrick Lambrix is a Professor and he leads the Database and Web Information Systems Group at IDA. Patrick has over 20 years of experience in research related to knowledge engineering, which includes aspects of Semantic Web, ontologies, and databases. Recent highlights include pioneering work in ontology alignment and ontology completion and debugging resulting in unique and award-winning systems. The systems and techniques developed by his group have been and are being used in different domains such as life sciences, animal health surveillance, libraries and materials design.
• Robin Keskisärkkä is PhD student at the Division for Human-centered systems (HCS) at the Department of Computer and Information Science. His research focuses on RDF Stream Processing (RSP) and semantic complex event processing, which leverages Semantic Web technologies for analyzing heterogenous streaming data in combination with static data. Robin has previously organized tutorials on the topics of RSP and stream reasoning at international conferences including WWW (2019) and ESWC (2019).