In this paper we consider a labor constrained scheduling problem (LCSP) which is a simplification of a practical problem arising in industry. Jobs are subject to precedence constraints and have specified processing times. Moreover, for each job the labor requirements varies as the job is...

We present and study a mixed integer programing model that arises as a sub-structure in any industrial applications. This model provides a relaxation of various capacitated production planning problems, more general fixed charge network flow problems, and other structured mixed integer programs....

In Van den Akker, Va, Hoesel, and Savelsbergh [1994], we have studied a tume-indexed formulation for single-machine scheduling problems and have presented a complete characterization of all facet inducing inequalities with right-hand side 1 and 2 for the convex hull of the monotone extension of...

We study a special case of a structured mixed integer programming model that arises in a number of applications. For the most general case of the model, called PI, we have earlier analyzed the polyhedral structure (Miller et al. [2000a]), including identifying facet-defining valid inequalities.

Instances of the multi-item capacitated lot-sizing problem with setup times (MCL) often appear in practice, either in standard form or with additional constraints, but they have generally been difficult to solve to optimality. In MCL demand for multiple items must be met over a time horizon,...

In Van den Akker, Van Hoesel, and Savelsbergh (1994), we have studied a time-indexed formulation for single-machine scheduling problems and have presented a complete characterization of all facet inducing inequalities with right-hand side 1 and 2 for the convex hull of the monotone extension of...

We consider the scheduling problem of minimizing the average wighted completion time of n jobs with release dates on a single machine. We first study two linear programming relaxations of the problem, one based on time-indexed formulation, the other on a completion-time formulation. We show...

Given a network, the facility location problem consists of locating a set of sites on the network to serve existing clients so as to minimize its total cost. Special cases include the simple plant location problem (SPLP), bank account location, p-facility location, and p-median problem.

We report new results for a time-indexed formulation of nonpreemptive single- machine scheduling problems. We give complete characterizations of all facet induc- ing inequalities with integral coecients and right-hand side 1 or 2 for the convex hull of the set of feasible partial schedules,...