184.730 Knowledge-based Systems
This course is in all assigned curricula part of the STEOP.
This course is in at least 1 assigned curriculum part of the STEOP.

2021S, VU, 4.0h, 6.0EC


  • Semester hours: 4.0
  • Credits: 6.0
  • Type: VU Lecture and Exercise
  • Format: Distance Learning

Learning outcomes

After successful completion of the course, students are able to apply techniques, methods, and algorithms of knowledge-based systems for theoretical and practical applications, as well as to use the gained knowledge in further courses.


  • Email address for questions: kbsci-2021s AT kr.tuwien.ac.at
  • The first lecture is on Wed Mar 03, 2021.
  • Mandatory TISS course registration until Mar 11, 2020.
  • Mandatory TUWEL entry test from Mar 12 to Mar 14, 2021 (00:00-23:55). Everybody who takes the entry test will receive a certificate (i.e., it is not possible to unregister after the entry test). If you stop participating after taking the entry test, you will receive a negative certificate.

Subject of course


The module discusses the following topics:

  • Rule-based systems and RETE
  • Predicate Logic (as a representation language)
  • Description Logics (ALC, Basics, Tableau)
  • Truth Maintenance Systems
  • Answer Set Programming
  • Probabilistic Reasoning


Lecture-Part: Uwe Egly, Thomas Eiter, and Hans Tompits
Exercise-Part: Antonius Weinzierl and Zeynep Saribatur

Course of Action and Topics of the Lecture Part

Attention: This semester, the course will be held in a distance-learning mode. For the lecture part, slides will be made available at the respective lecture dates in pdf form and as a video in TUWEL, and live question-and-answer (Q+A) sessions will be offered for each topic in subsequent weeks. The exercise part will also be held in distance mode for which we use the BigBlueButton system. For this, only a current browser, a microphone, and a webcam is required. Specific details will be given in due time. The exercise test in this semester will be held as written online exam on paper following the guidelines of TU Wien. In order to participate in the online exercise test, you need a webcam, a stable internet connection and either a printer or a second device with which you can view a PDF. If you otherwise cannot participate in the online exercise test, you may request a permit to write the test at the university. In case the situation permits, an ordinary presence exercise test at the university may substitute the online one.

  • Wed Mar 03: Introduction+History+Architecture, Rules I und Rules II as videos (Egly)
  • Wed Mar 10, 17:00-19:00: Q+A session on History & Architecture, Rules 1, Rules 2 (Egly)
  • Thu Mar 11: Registration deadline (TISS)
  • Fri Mar 12 to Sun Mar 14: Mandatory entry test (TUWEL)
  • Wed Mar 17: 17:00-19:00: online lecture PL1 as a specification language (Egly)
  • Wed Mar 24:
    1. Q+A session on PL1 & PL1 as a specification language (Egly)
    2.  Course material available on Description Logics I+II (Eiter)
  • Wed Mar 31: Easter break
  • Wed Apr 07: Easter break
  • Wed Apr 21 (Eiter):
    1. 17:00-19:00: Q+A on Description Logics
    2. Course material available on Truth Maintenance Systems
  • Tue Apr 27: Exercises Q&A Session - Sheet 1 (online; time TBA)
  • Wed Apr 28, 17:00-19:00: Q+A session on Truth Maintenance Systems (Eiter)
  • Fri Apr 30, 23:55: Deadline for Project 1 (TUWEL)
  • Sat May 01 to Sun May 02: Registration for a solution discussion for Project 1 (TUWEL)
  • Mon May 03 to Wed May 05: Project 1 solution discussion
  • Tue May 04: Exercises Q&A Session - Sheet 2 (online; time TBA)
  • Wed May 05: Course material available on Answer-Set Programming I+II, Probabilistic Reasoning (Tompits)
  • Wed May 12, 17:00-19:00: Q+A session on Answer Set Programming & Probabilistic Reasoning (Tompits)
  • Thu May 27: Exercises Q&A Session - Sheet 3 (online; time TBA)
  • Wed Jun 02, 23:55: Deadline for Project 2 (TUWEL)
  • Thu Jun 10: Mandatory exercise test
  • Jun 24, 13:00-16:00: Main exam (orally, 3 slots, 1h each, 3 students per slot)


Mandatory registration until Mar 11, 2020.

Mandatory TUWEL entry test from Mar 12 to Mar 14, 2020 (00:00-23:55). Everybody who takes the entry test will receive a certificate (i.e., it is not possible to unregister after the entry test).

Exercise test which covers 3 exercise sheet

Mandatory (closed book) online exercise test on (time TBA). The test examines the following three exercise sheets and their background:

  • Sheet 1: Rules + Predicate Logic
  • Sheet 2: Description Logics + Truth Maintenance Systems
  • Sheet 3: Answer Set Programming + Probabilistic Reasoning
  • Rewuired infrastructure for the online exercise test: stable internet connection, a device with webcam and microphone, either a printer or a second device to view a PDF, and a scanner or camera with software to generate a single PDF of the written test.
  • If situation permits, a written closed book exercise test at TU Wien may substitute the online one.

The lecturers will present the solutions and answer questions about the exercises in dedicated lecture units (to be announced via TISS notification and in TUWEL). Moreoever, students are invided to ask questions in the tutor hours (see TUWEL).

The test is evaluated with up to 27 points, where at least 14 are needed for a positive grade.

2 Projects

Two knowledge-based systems must be implemented:

  • Submission via TUWEL
  • Ontology project discussion May 03 to May 05, 2021
  • Automatic grading with testcases for the ASP project

Project submission deadlines:

  • Project 1: Apr 30, 2021
  • Project 2: Jun 02, 2021


  • Files must comply with the project specification!
  • No group work!
  • Exercises and projects must be worked out individually
  • Finalisation of points after plagiarism check (possibility of fines and negative grades)

Used tools:

  • Protege: http://protege.stanford.edu/
  • DLV: http://www.dlvsystem.com/
  • Potassco: http://potassco.sourceforge.net/

Teaching methods

Lecture part with recorded frontal lecture, additionally online meetings for questions+answers; exercise part with solving independently exercises and project tasks.

Mode of examination


Additional information

ECTS breakdown: 6 ECTS = 150 Hours

  • Lectures + Introduction 30h
  • Solving the exercises 30h
  • Preparation for the exercise test 15h
  • Exercise test 1h
  • Implementing and presenting the projects 20h
  • Preparation for the final exam 53h
  • Final exam 1h



Examination modalities

The assessment is based on an oral exam (online) and the performance in the exercises.

Course registration

Begin End Deregistration end
16.02.2021 00:00 11.03.2021 23:55 11.03.2021 23:55



No lecture notes are available.

Preceding courses


  • Attendance Required!