Many optimization problems have several equivalent mathematical models. It
is often not apparents which of these models is most suitable for practical
computation, in particular, when a certain application with a specific ran
ge of instance sizes is in focus. Our paper addresses the Asymmetric Travel
ling Salesman Problem with time windows (ATSP-TW) from such a point of view
. The real-world application we aim at is die control of a stacker crane in
a warehouse.
We have implemented codes based on three alternative integer programming fo
rmulations of the ATSP-TW and more than ten heuristies. Computational resul
ts for real-world instances with up to 233 nodes are reported, showing that
a new model presented in a companion paper outperforms the other two model
s we considered - at least for our special application - and that the heuri
stics provide acceptable solutions.