Business environments change over time. They are cyclic, show seasonality or just evolve over time. This is certainly true for customer demand. As a result, stationary demand distributions are crude approximations of true customer behavior at best. Yet, most classical stochastic inventory models...

This note clarifies some issues dealing with the necessary condition for the optimal terminal time in free terminal time optimal control problems. It is shown that this condition is independent of the other maximum principle conditions and a simple proof is presented. Also the economic...