In this paper, a generalization is presented of the newsboy problem where an emergency lot can be ordered to provide for a certain fraction of shortage. This fraction is described by a general backorder rate function which is non-increasing with respect to the unsatisfied demand. An exponential...

In this paper, we study a stochastic sequential ordering problem, where a set of jobs must be scheduled on a single machine. The jobs have stochastic processing times and verify certain precedence relations. For each job, there also exists a time window characterized by the release time and the...

We address a multi-echelon inventory system with one-warehouse and N-retailers. The demand at each retailer is assumed to be known and satisfied by the warehouse. Shortages are not allowed and lead times are negligible. Costs at each facility consist of a fixed charge per order and a holding...