A stochastic model for forecast consumption in master scheduling

This paper describes a stochastic model for the reduction of the initial forecast in the Master Schedule (MS) of an MRP system during progress of time by the acceptance of customer orders. Results are given for the expectation and variance of the number of yet unknown deliveries as a function of futurity within the planning horizon. The expectation will be a measure for the forecast. The result for the variance is a measure for the forecasting error and may act as a basis for the amount of safety stock or available to promise, to project in the MS

Multiple batch structures in throughput scheduling

Throughput scheduling deals with maximizing time-constrained throughput in batch production. Previous investigations have shown that time-constrained throughput increases by processing successive batch cycles in simple process configurations consisting of three processes and two facilities, even if set-up times are positive. This paper explores the extension of these results to more complex process configurations

Heterogeneous batch structures in throughput scheduling

Recently a few papers appeared on throughput scheduling, dealing with the relationship between batch structure and process structure in discrete batch production, while maximizing time-constrained throughput. Results have been concentrated on the class of homogeneous batch structures, i.e. batch structures with equal batch sizes for each process per cycle. In this paper heterogeneous batch structures are considered. By numerical examples, it is shown that heterogeneous batch structures can outperform the best result obtained by considering only homogeneous batch structures. Moreover integer programs are developed, which generate such solutions

Maximizing throughput in some simple time-constrained scheduling situations

This contribution focuses on some interesting phenomena occurring in scheduling capacity constrained resources in time-constrained situations. The scheduling situations considered form part of a simulation game developed to assist in teaching the scheduling philosophy of Optimized Production Technology (OPT) to production managers. It is shown that under certain conditions on set-up and processing times, advanced examples may be constructed combining three of the four complicating conditions mentioned m the OPT-literature. In addition, some interesting properties of process batches yielding a maximum throughput in such cases is considered