The following technical report is available from
http://aib.informatik.rwth-aachen.de:
Adjoint Code by Source Transformation with OpenAD/F
Uwe Naumann, Jean Utke, Patrick Heimbach, Chris Hill, Derya Ozyurt,
Carl Wunsch, Mike Fagan, Nathan Tallent, Michelle Strout
AIB 2006-05
This document reports on recent advances in the development of the adjoint
code generator OpenAD/F. We give an overview of the software design, and
we discuss case studies that illustrate the feasibility of adjoint code
generation. Our main target application is the MIT General Circulation
Model --- a numerical model designed for study of the atmosphere, ocean,
and climate.
The following technical report is available from
http://aib.informatik.rwth-aachen.de:
Counterexamples in Probabilistic Model Checking
Tingting Han, Joost-Pieter Katoen
AIB 2006-09
This paper considers algorithms and complexity results for the generation
of counterexamples in model checking of probabilistic until-formulae
in discrete-time Markov chains (DTMCs). It is shown that finding the
strongest evidence (i.e, the most probable path) that violates a (bounded)
until-formula can be found in polynomial time using single-source
(hop-constrained) shortest path algorithms. We also show that computing
the smallest counterexample that is mostly deviating from the required
probability bound can be found in a pseudo-polynomial time complexity
by adopting a certain class of algorithms for the (hop-constrained) $k$
shortest paths problem.
The following technical report is available from
http://aib.informatik.rwth-aachen.de:
Model Checking Software for Microcontrollers
Bastian Schlich, Michael Rohrbach, Michael Weber, Stefan Kowalewski
AIB 2006-11
A method for model checking of microcontroller code is presented. The
main objective is to check embedded C code including typical hardware
specific ingredients like embedded assembly statements, direct memory
accesses, direct register accesses, interrupts, and timers, without
any further manual preprocessing. For this purpose, the state space is
generated directly from the assembly code that is generated from C code
for the specific microcontroller, in our case the ATMEL ATmega family. The
properties to be checked can refer to the global C variables as well as
to the microcontroller registers and the SRAM. By this approach we are
able to find bugs which cannot be found if one looks at the C code or
the assembly code alone. The paper explains the basic functionality of
our tools using two illustrative examples.