[since March 2012] Senior researcher at the Institute of Transportation
Systems of the German Aerospace Center (DLR TS), in the division Rail
[2003-2012] Senior researcher at the research institute OFFIS
[2002-2003] Assistant at the chair of Programming Systems
and Compiler Construction, University Dortmund
[2000-2002] Director of research at METAFrame Technologies, Dortmund
[1994-2000] Researcher at OFFIS
 Visiting Scientist at the Siemens AG
[SS 1995] Substitute Professorship at the University of the
Saarland for "Distributed Systems"
 Visiting Scientist at the University Uppsala,
Department of Computer Systems
[1990-1994] Research Assistant at the Chair for Computer Architecture,
[1985-1990] Teaching Assistant at the Chair of Compiler Construction,
 Habilitation at the Carl-von-Ossietzky-Universtiy, Oldenburg,
with a thesis on "Beyond Finite-State
Model Checking: Verifying Large and Infinite Systems".
 PhD in Computer Science at the Christian-Albrechts-University,
Kiel, with a dissertation on "Complexity Issues of Hoare-Style Proof
Systems: Efficient Proof Construction and Complexity-Induced Limitations
of Certain Proof Systems".
 Diplom (Master) in Computer Science at the
Christian-Albrechts-University, Kiel, with a thesis on "Examinations of the
Expressiveness of Logical Formulas wrt. the Input/Output Relation