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The introduction of extended producer responsibility forces Original Equipment Manufacturers to set up a logistic network for take back, processing and recovery of discarded products. In this paper, we discuss a business case study carried out at Océ, a copier firm in Venlo (NL). It concerns the installment of remanufacturing processes. There is a choice from two locations in Venlo (NL) and one in Prague (Czech Republic), where assignments are subjected to managerial constraints. The study is meant to verify whether the strategic decision of Océ to move remanufacturing activities to the Czech Republic is also economically feasible. We limit ourselves to an optimisation of the HV02-machine network. We follow our general approach, in which we first determine how return products are processed (recovery strategy) and subsequently optimise the reverse logistic network design. We optimise on total operational costs over all possibilities and also compare three pregiven managerial solutions (=network designs) with a Mixed Integer Linear Programming model. Differences in economic costs appear to be very small, hence installing recovery activities in Prague for the HV02-machine must be well motivated from a strategic point of view. Moreover, we argue that besides cost minimisation, Océ should include performance indicators, such as JIT, reliability, in logistic optimisation to support its quality oriented business strategy. In addition, we discuss aspects regarding specific modelling elements in this case situation, the definition of cost functions, the possibility of optimising the forward and reverse logistic network and the use of LP-versus MILP-models in this kind of situations.

The part feeding problem at automotive assembly plants deals with the timely supply of parts to the designated stations at the assembly line. According to the just-in-time principle, buffer storages at the line are frequently refilled with parts retrieved from a central storage area. In the industrial application at hand, this is accomplished by means of an internal shuttle system which supplies the various stations with the needed parts based on a given assembly sequence. The main objective is to minimize the required number of shuttle drivers. To solve this inhouse transportation problem, a heuristic solution procedure is developed which is based on the decomposition of the entire planning problem into two stages. First, transportation orders are derived from the given assembly sequence. In the second stage, these orders are assigned to tours of the shuttle system taking transportation capacity restrictions, due dates and tour scheduling constraints into account. Numerical results show that the proposed heuristic solves even large-sized problem instances in short computational time. Benchmark comparisons with Kanban systems reveal the superiority of the proposed predictive part feeding approach.

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