Optimal control of hereditary inventory systems with short-time conservation effects

In this paper, an inventory system with short-time conservation effects of perishable goods is modelled by differential-delay equations. Conservation effect is considered as delayed deterioration of goods. The delayed ordering rate may occur too. For the continuous-time version the optimality results, including the case of non-homogeneous state equations, are formulated in a way in which sensitivity results, derived by Bogataj, could be used directly.