abstract = "Dynamic flexible job shop scheduling is a challenging
combinatorial optimisation problem due to its complex
environment. In this problem, machine assignment and
operation sequencing decisions need to be made
simultaneously under the dynamic environments. Genetic
programming, as a hyper-heuristic approach, has been
successfully used to evolve scheduling heuristics for
dynamic flexible job shop scheduling. However, in
traditional genetic programming, recombination between
parents may disrupt the beneficial building-blocks by
choosing the crossover points randomly. This paper
proposes a recombinative mechanism to provide guidance
for genetic programming to realise effective and
adaptive recombination for parents to produce
offspring. Specifically, we define a novel measure for
the importance of each subtree of an individual, and
the importance information is used to decide the
crossover points. The proposed recombinative guidance
mechanism attempts to improve the quality of offspring
by preserving the promising building-blocks of one
parent and incorporating good building-blocks from the
other. The proposed algorithm is examined on six
scenarios with different configurations. The results
show that the proposed algorithm significantly
outperforms the state-of-the-art algorithms on most
tested scenarios, in terms of both final test
performance and convergence speed. In addition, the
rules obtained by the proposed algorithm have good
interpretability.",
notes = "Evolutionary Computation Research Group, School of
Engineering and Computer Science, Victoria University
of Wellington, Wellington 6140, New Zealand.