Hanafi et al. [42] study the weekly sectorization problem
regarding household waste collection, with the aim of determining
a fixed number of sectors which should be balanced with respect
to daily total time for collection tasks. For this problem, they
propose an optimization model that is not easily solvable for largesized
instances. Thus, a local search heuristic that is based on the
definition of a new effective data structure (sectorization matrix)
is described. The proposed methods are tested on three real-world
instances (related to Quito in Ecuador and Echirolles and Saint-
Martin d'Heres in France) and 28 randomly generated instances.