Piracy in the Gulf of Aden and the waters around Somalia has increased in recent years, with international naval assets allocated to patrol at-risk areas. This paper compares measures of effectiveness of area coverage in situations where there is a uniform piracy risk and where some areas are more vulnerable than others. Simulated annealing was used to allocate the patrolling naval assets. The
... [Show full abstract] novel problem of positioning a coalition of ships whilst incorporating the transit of a non-coalition ship that may respond to a piracy incident but can not be prepositioned is addressed.