Discrete Lot-Sizing and Scheduling Problem
The Discrete Lot-Sizing and Scheduling Problem ( DLSP ) is a model of dynamic lot-size planning , with limited capacity and multiple products .
It is based on many very short periods (so-called micro periods) in which only a single product can be manufactured at a time. Setup costs are only incurred if another product is to be manufactured in the subsequent period. So not only the lot size is determined, but also the order of the lots to be produced . The DLSP is therefore suitable for short-term detailed planning.
In contrast to this, in the Capacitated Lot-Sizing Problem (CLSP) it is possible to place several lots within one of the longer periods (weeks to months). A sequence of the lots to be produced in a period is not determined there, so that the CLSP is suitable for medium to long-term planning .
Description of the model
The DLSP makes the following assumptions:
- single-stage, multi-product production
- finite production speed
- demand that changes over time (dynamic demand)
- the means of production (machines) are only available for a limited time within the individual periods. The available capacity is identical for each period.
- Fixed set-up costs are only incurred for placing a batch if another product was manufactured in the previous period.
- A lot is generally produced over an entire period.
- the storage costs are proportional to the quantity stored
- finite planning period
solution
For the exact solution is mostly used branch and bound - algorithms . There are also heuristics that often only deliver minimally worse results (around 1%).
Individual evidence
- ↑ Domschke, Scholl, Voss: Production planning: process organizational aspects . 2nd edition, Springer, Berlin, 1997, pp. 133, 146-150.
- ↑ Domschke, Scholl, Voss: Production planning: process organizational aspects . 2nd edition, Springer, Berlin, 1997, p. 146.
- ↑ Domschke, Scholl, Voss: Production planning: process organizational aspects . 2nd edition, Springer, Berlin, 1997, p. 150.