Presentations at Conferences, Workshops and Seminars

The following is a selection of talks I have given in the past years. Some slides are hyperlinked. If you want slides for other talks, please email me.

Invited Talks
Fixed-Point Logics: from Elementary Induction on Abstract Structures to Databases and Descriptive Complexity
VIG 2011, Symposium in Honour of Yiannis Moschovakis at the UCLA Logic Center, 2011.
Lower Bounds for Algorithmic Meta Theorems
Logic Colloquium 2009, Annual Meeting of the Association for Symbolic Logic, 2009.
Graph Searching Games
Games Spring School 2009, organised by the ESF network Games for Design and Verification, 2009.
Algorithmic Meta-Theorems
International Workshop on Parameterized and Exact Computation (IWPEC), 2008.
Complexity of First- and Monadic Second-Order Logic
Spring School of the ESF network Model Theory (MODNET), 2008.
Graph Searching Games, Fall School on algorithmic graph minor theory
organised by the graduate school "Methods for Discrete Structres", Berlin, 2007.
(Finite) Model Theory of Trees and Tree-Like Structures
Workshop on "Finite and Algorithmic Model Theory", Durham, UK, 2006.
Approximation through Logic
Logic Colloquium, Annual meeting of the Association for Symbolic Logic, Athens, Greece, 2005.
Expressive Equivalence of Least and Inflationary Fixed-Point Logic
Colloquium Logicum / PhD Colloquium, Münster, Germany, 2002.
Talks at Internat. Conferences
Model Checking for Successor-Invariant FO on Minor-Closed Graph Classes
ACM/IEEE Symp. on Logic in Computer Science (LICS), 2013.
Graph Operations on Parity Games and Polynomial-Time Algorithms
ACM/IEEE Symp. on Logic in Computer Science (LICS), 2013.
Packing directed cycles through a specified vertex set
ACM/SIAM Symp. on Discrete Algorithms (SODA), 2013.
Directed Nowhere Dense Classes of Graphs
ACM/SIAM Symp. on Discrete Algorithms (SODA), 2012.
On the Parameterised Intractability of Monadic Second-Order Logic
International Conference on Computer Science Logic (CSL), 2009.
On Datalog vs. LFP
International Coloquium on Automata, Languages and Programming (ICALP), 2008.
Locally Excluding a Minor
IEEE Symposium on Logic in Computer Science (LICS), 2007.
Digraph Measures: Kelly Width, Games, and Orderings
ACM-SIAM Symposium on Discrete Algorithms (SODA), 2007.
Approximation Schemes for First-Order Definable Optimisation Problems
IEEE Symposium on Logic in Computer Science (LICS), 2006.
Backtracking Games
International Colloquium on Automata, Logic, and Programming (ICALP), 2004.
An Alternative Semantics for Partial Fixed-Point Logic
Conference of the European Association for Computer Science Logic (CSL), 2002.
Expressive Equivalence of Least and Inflationary Fixed-Point Logic
IEEE Symposium on Logic in Computer Science (LICS), 2002.
Inflationary Fixed Points in Modal Logic
Conference of the European Association for Computer Science Logic (CSL), 2001.
Query-Languages for Constraint Databases: First-Order Logic, Fixed-Points, and Convex Hulls
International Conference on Database Theory (ICDT), 2001.
Fixed-Point Query Languages for Linear Constraint Databases
19th ACM Symposium on Principles of Database Systems (PODS), 2000.
Descriptive Complexity Theory for Constraint Databases
Conference of the European Association for Computer Science Logic (CSL), 1999.
Talks at Departmental Seminars
Computing Excluded Minors
University of Leeds, Department of Pure Mathematics, Logic Seminar, Leeds, UK, 25.2.2009.
Deciding First-Order Properties of Nowhere Dense Graphs
University of Warzaw, Warzaw, 30.7.2013.
Algorithmic Applications of Sparse Classes of Graphs
Graduate School "Methods for Discrete Structures", Berlin, 9.12.2013.
Tractability through Graph- and Digraph Minors
University "La Sapienza" of Rome, 22.5.2013.
Graph Searching Games, Departmental Seminar
University of Durham, Durham, UK, 25.2.2008.
Graph Searching Games, Departmental Seminar
Royal Holloway, University of London, Egham, UK, invited by Prof. Gutin, 12.2.2008.
Digraph Decompositions
Oxford University Computing Laboratory, invited by Prof. Gottlob, Oxford, UK, 25.5.2006.
Graph Decompositions and Applications
Short Course am Isaac Newton Institute for Mathematical Sciences, Cambridge, 25.4., 27.4., 2.5., 4.5.2006.
Approximation Schemes for First-Order definable Optimisation Problems
Isaac Newton Institute for Mathematical Sciences, Cambridge, 4.4.2006.
DAG-Decompositions and Parity Games
European Graduate School “Combinatorics, Geometry, Computation”, TU Berlin, 13.2.2006.
DAG-Decompositions and Parity Games
Mathematical Institute, Warsaw University, invited by Prof. Niwinski, 18.11.2005.
DAG-Decompositions and Parity Games
Seminarvortrag an der Graduiertenschule “Mathematical Logic and Applications”, Albert-Ludwigs-Universität Freiburg, invited by Prof. Lausen, 5.12.2005.
Fixed-Point Logics and Inductive Definitions
Seminarvortrag an der Graduiertenschule “Mathematical Logic and Applications” Albert-Ludwigs-Universität Freiburg, invited by Prof. Flum, 28.6.2004.
Kleinste und Inflationäre Fixpunktlogik
University of Bonn, invited by Prof. Köpke, 20.1.2004.
Once Upon a Time in the West, “Logic and Semantics Seminar”
University of Cambridge, invited by Dr. Dawar, 29.5.2003.
Least and Inflationary Fixed-Point Logic
University of Athens, invited by Professor Moschovakis, 5.10.2001.
Talks at Workshops
Dominating Sets and Network Centres in Nowhere-Dense Classes of Graphs
Workshop Algorithmic Graph Theory, Warwick, 2009.
On the fixed-parameter intractability of monadic second-order logic
AlMoTh-Seminar, Dortmund 2009.
Logical Methods in Graph Minor Theory
Workshop on Graph Minors, BIRS, Banff, Canada, 2008.
Locally Excluded Minors
Dagstuhl-Seminar on parameterized complexity, 2007.
Locally Excluding a Minor
AlMoTh-Seminar, Aachen, 2007.
Digraph Decompositions
Workshop on Graph Searching, Theory, and Applications, Anogia, Kreta, 2006.
DAG-Width and Parity Games
AFM-Seminar, Aachen, 2006.
Backtracking Games
Annual Meeting of the EU Training- and Research Network “Games and Automata for Synthesis and Validation (GAMES)”, Bordeaux, France, 2006.
Backtracking Spiele
AFM-Seminar, Berlin, 2004.
Once Upon a Time in the West
Annual Meeting of the EU Training- and Research Network “Games and Automata for Synthesis and Validation (GAMES)”, Vienna, 2003.
Generalising Automaticity to Modal Properties of Finite Structures
AFM-seminar, Aachen, 2002.
Least vs. Inflationary Fixed-Point Logic
Workshop “Parameterised Complexity”, AFM-seminar, Freiburg, 2001.
Fixed-Point Logics on Constraint Databases - Model-Theoretical vs. Operational Semantics
AFM-seminar, Mainz, 2001.
View-Based Query Processing
Workshop "Semi-Structured Data Models", AFM-Seminar, 2000.
Fixed-Point Query Languages for Linear Constraint Databases
Workshop on Finite Model Theory, CIRM, Luminy, Marseille, Frankreich, 2000.
Descriptive Complexity Theory for Constraint Databases
Workshop on Finite Model Theory and its Applications, LICS 1999, Trento, Italien, 1999.
Query Safety with Constraints
Workshop "Spatial Databases", AFM-Seminar, Mainz, 1999.