A note towards improved homeland defense

We indicate a number of shortcomings in the second stage in the approach of Bell et al. [1] that may lead to unsatisfactory results. Some possible remedies are investigated.

► A recently proposed two-stage covering/p-median (resp. p-center) approach for homeland defense system design is examined.
► Examples exhibiting unsatisfactory final outcomes are given.
► The second p-median-stage is adapted and two post-p-center third stages are suggested to avoid such difficulties.
► Ways are given to check and handle possible alternative optimal solutions.
► Special care needed in case of varying critical distances is described.