On a very abstract level, an information system consists of a set of system elements which communicate with each other. Communication is an unproductive operation, so the time needed to communicate data should be kept as short as possible and, to put it in monetary terms, the opportunity costs...

Resource-constrained project scheduling under a net present value objective attracts growing interest. Because this is an NP-hard problem, it is unlikely that optimum solutions can be computed for large instances. Thus, heuristics have become a popular research field. Up to now, however, tight...

This paper deals with proportional lot sizing and scheduling (PLSP) and gives some insights into the properties of this problem. Such insights may be useful for developing heuristic and/or exact solution procedures. The emphasis of this paper is on the multi-level, multi-machine case. We provide...

This contribution generalizes the work of Drexl and Haase about the so-called proportional lot sizing and scheduling problem which was published in 1995. While the early paper considers single-level cases only, the paper at hand describes multi-level problems. 1t provides mixed-integer programs...

A flow line consists of a sequence of work places (or stations) through which one or more producta (or models) move one-way in order to be processed. Each model requires specific Operations which must be performed in a predefined Order. To be able to do so, the stations must be equipped with...