More recently, Hansmann and Zimmermann [61] and Baudach
et al. [62] propose a three-phase approach to determine the route
plans and the crew schedules in a waste management system.
In particular, in Phase 1 they generate the daily crew tasks, including
the routes and the assignment to days, with minimum number of
crews required for the disposal process. Then, in Phase 2 they
generate the daily crew tasks (including routes and assignment to
days) with respect to the minimum number of crews from the
previous phase, ensuring a good “similarity” between the routes in
a daily crew task, and minimizing the maximum duration of a
daily crew task. Finally, Phase 3 amounts to assigning the employees
to the daily crew tasks (from Phase 2) for all working days over
a year, optimizing the goals from the crew scheduling perspective.