The Connectedness of Clash-free Timetables
Department of Computer Science
University of Erlangen-Nuremberg, Germany
We investigate the connectedness of clash-free timetables with
respect to the Kempe-exchange operation.
This investigation is related to the connectedness of the search
space of timetabling problem instances, which is a desirable property,
for example for twostep
algorithms using the Kempe-exchange during the optimization step.
The theoretical framework for our investigations is based on the
study of reconfiguration graphs, which
model the search space of timetabling problems.
We contribute to this framework by including
period availability requirements in the analysis and,
as a result, we derive improved
conditions for the connectedness of clash-free timetables in this
setting. We further show
that the diameter of the reconfiguration graphs increases only
linearly due to the period
We apply the theoretical insights to establish the connectedness
of clash-free timetables for a number of benchmark instances.
Proc. 10th Int. Conf. on the Practice and Theory of Automated
Timetabling (PATAT), pp. 330--346, 2014.
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