In this work, we have defined a problem important to the
pharmaceutical industry, reviewed relevant related published
works, developed a model to cover the global network allocations
and allocation transfers and investigated two solution
algorithms to tackle this particular large MILP problem.
In the spatial decomposition method, the sensitivity analysis
to the changeover time shows that, for this particular set
of data, the optimum value is not affected significantly, since
the bottleneck of the supply chain is the capacity of primary
sites. On the other hand, the CPU time increases significantly.
This is particularly the case for the “critical” secondary geographical
areas, where j = 2 and j = 4. These correspond to areas
where the capacity used is close to the limit, mainly due to a
lower excess capacity (Eq. (45)), which becomes more critical
as the changeover time increases.
The temporal decomposition method performs well with
these sets of data although the quality of the results may be
poor in other cases. Nevertheless, it opens new possibilities
to explore even larger instances of the problem, such as its
stochastic version, where demand and other parameters may
be uncertain.