Huang et al. [36] solve the problem of allocating municipal
waste flow under uncertainty using a case study from the
Municipality of Hamilton-Wentworth in the Province of Ontario.
They propose an approach based on Grey Linear Programming
(GLP), a method that is able to deal with interval input data, in
which problems containing interval parameters are transformed
into a pair of deterministic submodels. When solved in tandem,
such models guarantee stable upper and lower limits for the
solution. This transformation is executed in a prescribed order
using the output from the first submodel as direct input into the
second submodel. The final output of the method is a set of stable
interval values for the objective function and for all decision
variables related to uncertainty, such as the quantity of waste
generated at each district. Using GLP, Huang et al. [36] are able to
determine a solution for the case study, in which the existing
system cost could be consistently reduced with only minor
changes to the existing waste management scheme.