Foundations of Informatics

This page covers the third week of the Foundations of Informatics Bridging Course in Winter Semester 2013/14, held from February 24 to 28, 2014 at b-it, Bonn.

The following topics are covered:

Regular Languages
1. Formal Languages
2. Finite Automata
3. Regular Expressions
4. Minimization of Deterministic Finite Automata
5. The Pumping Lemma
Context-Free Languages
1. Context-Free Grammars and Languages
2. Context-Free and Regular Languages
3. Decidability Problems of Context-Free Languages
4. Closure Properties of Context-Free Languages
5. Pushdown Automata

After passing this part of the course, participants are expected to have acquired the following skills:

Regular Languages:
- to give the basic definitions of finite automata and regular expressions;
- to construct a finite automaton or a regular expression from a given language specification;
- to translate a regular expression into an equivalent finite automaton;
- to compute the set of reachable states of a finite automation with respect to a given input word;
- to remove ε-transitions from a finite automaton;
- to apply the powerset construction to turn a nondeterministic finite automaton into a deterministic one;
- to minimize a given deterministic finite automaton; and
- to apply the Pumping Lemma to show that a given language is not regular.
Context-Free Languages
- to give the basic definitions of context-free grammars and pushdown automata;
- to construct a context-free grammar or a pushdown automaton from a given language specification;
- to turn a given context-free grammar into Chomsky normal form;
- to apply the CYK algorithm to decide the word problem for a context-free grammar;
- to apply the marking algorithm to decide the emptiness problem for a context-free grammar; and
- to translate a context-free grammar into an equivalent pushdown automaton.

The presentation of the contents is mainly based on the following slides. Sometimes the board is used to develop an example or a formal proof.

Moreover, the following textbooks provide additional information.

J.E. Hopcroft, R. Motwani, J.D. Ullmann: Introduction to Automata Theory, Languages, and Computation, 2nd ed., Addison-Wesley, 2001
A. Asteroth, C. Baier: Theoretische Informatik, Pearson Studium, 2002 [in German]

BSc/MSc/Diploma Topics
Teaching WS 2012/13
Hybrid Systems Group

We are looking for a HiWi for the Compiler Construction course. If you are interested, please contact Thomas Noll.

Joost-Pieter Katoen has been appointed as a member of the renowned Academia Europaea (Academy of Europe), a European, non-governmental association acting as an Academy whose members are scientists and scholars who collectively aim to promote learning, education and research.

Vacancies for postdoctoral researchers in "Automated Analysis of Probabilistic Programs". Application deadline: August 15, 2013.

Joost-Pieter Katoen has been awarded a Distinguished Professorship from the RWTH Aachen University.

The Hybrid Systems: Computation and Control (HSCC'13) conference in Philadelphia has been very successful: Hongfei Fu received the best student paper award for his paper "Approximating acceptance probabilities of CTMC-paths on multi-clock deterministic timed automata". Besides, the paper by Ilya Tkachev, Alexandru Mereacre, Alessandro Abate and Joost-Pieter Katoen was ranked second in the overall best paper award selection.

Joost-Pieter Katoen has been elected as Steering Committee Chair of ETAPS (www.etaps.org), the largest conference on theory and practice of software in Europe. He is the first non-UK ETAPS SC chair since the conference was initiated in 1998. More information here.

The Alumni-Magazine of RWTH Aachen University contains an interview with our former PhD student and postdoctoral researcher, Dr. Tingting Han.

HiWi's wanted to work in a new European Space Agency project for enhancing state-of-the-art design and analysis tools (COMPASS) for the next generation European rockets. Need programming and model checking affinity. See here for details and contact.

We offer openings for several PhD candidates in the area of
"Model-Based Design and Analysis for Dependable Software Systems". Deadline for application: September 14, 2012. For further information click here.

The Theory of Hybrid Systems Group offers two jobs as student assistants within the CEBug project. For more information, look here.

Dino Distefano received the prestigious Roger Needham Award for his work on software verification. This award is for a distinguished research contribution in computer science by a UK based researcher who has completed up to 10 years of post-doctoral research. Dr. Distefano was the first PhD student supervised by Joost-Pieter Katoen.

Marijn Jongerden received the German MMB (Messung, Modellierung und Bewertung von Rechensystemen) Award 2012 of the GI/ITG-Committee for Measurement, Modelling and Evaluation of Computing Systems for his PhD-thesis on "Model-based energy analysis of battery powered systems". His work was supervised by Boudewijn Haverkort (Twente) and Joost-Pieter Katoen.

Our paper "Formal Correctness, Safety, Dependability and Performance Analysis of a Satellite" has been accepted to ICSE 2012 in the track SE in Practice (18% acceptance rate). The paper treats a new satellite from the European Space Agency that was modeled and analyzed with modern tools during the actual satellite design.

Joost-Pieter Katoen will act as DJ in the "Nacht der Professoren" in the Apollo bar and cinema.