Mainstream research in priority dispatching has considered jobs with equal delay penalties, thereby ruling out strategic differentiation of customer orders. We develop and test efficient dispatching rules for the weighted tardiness problem with job-specific due dates and delay penalties. Our...

The rate at which Markov decision processes converge as the horizon length increases can be important for computations and judging the appropriateness of models. The convergence rate is commonly associated with the discount factor \alpha . For example, the total value function for a broad set of...

By allowing disposal in each period, a sequence of upper and lower bounds on the infinite horizon nonstationary periodic review inventory problem is obtained. The nth bounds depend only on knowledge of the demand distributions in the first n periods, giving planning horizon results. In general,...

The problem of financing risky R&D projects over time has been stated as an optimal control problem by Hess [Hess, S. W. 1962. A dynamic approach to R&D budgeting and project selection. IRE Transactions on Engineering Management EM-9 (December) 170-178.], Lucas [Lucas, Robert E. 1971. Optimal...

Nonstationary stochastic periodic review inventory problems with proportional costs occur in a number of industrial settings with seasonal patterns, trends, business cycles, and limited life items. Myopic policies for such problems order as if the salvage value in the current period for ending...

Increasing product complexity, manufacturing environment complexity and an increased emphasis on product quality are all factors leading to uncertainties in production processes. These uncertainties are in the form of unplanned machine maintenance, varying production yields and rework, among...

This paper details the application of a class of heuristics to the Fixed-life Perishability Problem formulated by Nahmias (1975a) and Fries (1975). Various assumptions for this model include i.i.d. demand, linear ordering, holding and penalty costs. Goods have a known fixed lifetime and perished...

We examine the problem of scheduling a given set of jobs on a single machine to minimize total early and tardy costs. Two dispatch priority rules are proposed and tested for this NP-complete problem. These were found to perform far better than known heuristics that ignored early costs. For...

Although Horn, Sidney and Lawler have considered the problem of minimizing weighted mean flow time for n jobs with precedence constraints on one machine, practical exact algorithms for the general case remain elusive. Two relatively sophisticated heuristics are presented which are...

Modelling planning problems that extend over many time periods as linear programs leads to a special structure called a "staircase" or "dynamic" linear program. In this special structure, the nonzero coefficients of the linear program appear in blocks along the "main diagonal" of the coefficient...