Optimal inventory control in cardboard box producing factories : a case study

[摘要] ENGLISH ABSTRACT: This thesis is a case study in optimal inventory control, applied to Clickabox factory, aSouth African cardboard box producer from whom cardboard boxes may be ordered atshort notice via the internet.The problem of developing a decision–support system for optimal stockholding at thefactory, in order to minimize cardboard off–cut wastage subject to required service levels,is addressed in this thesis. Previously a simple replenishment policy, based largely onexperience, was implemented at the factory. The inventory model developed for andapplied to Clickabox in this thesis takes account of a raw materials substitution cascade,as well as the stochasticity of demand, and other factors such as cost, service level andspatial requirements for the storage of stock. This combination of stochastic demand andproduct substitution has not, to the author's knowledge, previously been dealt with inthe literature.There are two primary deliverables of this study. The first is a suggestion as to the suitablestock composition (cardboard types from which boxes may be manufactured) to be keptin inventory at the factory. The second deliverable is a computerised decision–supportsystem, based on the inventory model developed, to aid in future inventory replenishmentdecisions at Clickabox.Some of the results of this thesis have, at the time of writing, already been implementedwith success at the factory. These include the suggestions given to the managementof Clickabox as to the suitable stock types to be held in inventory, which have beenimplemented in stages since March 2003. The suggested stock composition has proven tobe superior to the previous stock types held, in terms of a reduction in off–cut wastageand increased availability of suitable boards.

[发布机构] Stellenbosch University