In this paper we study the problem of determining a production schedule for an order of n jobs on a single machine which is subject to stochastic machine failures. To avoid long downtime of the machine caused by unexpected failures, preventive maintenance should be planned as well. If a failure...

This paper calls for a change in paradigm in lot sizing and scheduling. Traditionally, a discrete time scale is chosen to model lot sizing and scheduling. As an alternative, the so-called block planning concept is proposed which is based on a continuous representation of time. A mixed-integer...

A new model formulation is developed for reducing the workload in pre-batching at a manufacturer of flavours and fragrances, by optimally assigning ingredients to different storage types, taking into account past usage of ingredients and several restrictions about volumes and number of storage...

Quite often transportation companies face two types of jobs, ones which they can plan themselves and ones which have to be done on call. In this paper we study the scheduling of these jobs, while we assume that job durations are known beforehand as well as windows in which the jobs need to be...

This paper deals with real-time disruption management of rolling stock in passenger railway transportation. We present a generic framework for modeling disruptions in railway rolling stock schedules. The framework is presented as an online combinatorial decision problem where the uncertainty of...

We establish the computational complexity of the problem of minimizing makespan in a flowshop, where each jobs requires a pallet the entire time, from the start of its first operation until the completion of the last operation. We prove that the problem is NP-hard in the strong sense for m =2...

Scheduling methods are proposed for a class of flexible manufacturing systems consisting of machine centers served by a cyclic conveyor. The minimization of finish time is considered as the optimization criterion. An optimal algorithm is proposed for the minimum conveyor speed (S = 1) for a...

This paper presents an asymptotic analysis of hierarchical production planning in a manufacturing system with two tandem machines that are subject to breakdown and repair. Since the number of parts in the buffer between the two machines needs to be non-negative, the problem is inherently a state...

The optimal production control problem of deterministic pull flow lines with multiple part types is considered in this paper. The last machine is assumed to be the bottleneck. The objective is to minimize the total inventory and backlog costs over time. We give an optimal production policy and...

Parallel machine structure is very common in modern production systems. Its performance sometimes has a decisive impact on the whole productivity. In this paper, we consider a parallel-machine scheduling problem where each machine is subject to periodic maintenance. Instead of assuming all the...