We present a new heuristic method to approximate the set of Pareto-opt
imal solutions in multicriteria optimization problems. We use genetic
algorithms with an adaptive selection mechanism. The direction of the
selection pressure is adapted to the actual stare of the population an
d forces it to explore a broad range of so far undominated solutions.
The adaptation is done by a fuzzy rule-based control of the selection
procedure and the fitness function. As an application we present a tim
etable optimization problem where we used this method to derive cost-b
enefit curves for the investment into railway nets. These results show
that our fuzzy adaptive approach avoids most of the empirical shortco
mings of other multiobjective genetic algorithms.