We can reformulate a vehicle routing problem (VRP) as an open shop scheduling problem (SSP) by representing visits as activities, vehicles as resources on the factory floor, and travel as set up costs between activities. In this paper we present two reformulations: from VRP to open shop, and the inverse, from SSP to VRP. Not surprisingly, VRP technology performs poorly on reformulated SSP’s, as...

In this paper we study both the nonpreemptive and preemptive versions of the popular unit-time open shop scheduling problem. For the set of feasible schedules, we construct the linear description of the convex hull of the vectors of the job completion times. Based on the properties of the resulting scheduling polyhedron, we show that the problem of constructing an optimal schedule minimizing an...

In the automotive industry, a new body shop production-line needs to be set up for almost every new car model. Due to the relatively short product life cycles, the planning process of body shops can almost be regarded as continuous. A main problem is to find an efficient layout fulfilling the desired production rate which is characterized by small buffer sizes and optimized cycle times. Often, ...

The problem of makespan minimization in a flow shop with two machines when the input buffer of the second machine can only host a limited number c of parts is known to be NP-hard for any c > 0 and c ≤ n, where n is the number of jobs. In this paper we analyze this problem in the context of batch scheduling, i.e, when identical parts must be processed consecutively. In particular we study the ca...