@inproceedings{EnglbergerHerrmannClaus, author = {Englberger, Julian and Herrmann, Frank and Claus, Thorsten}, title = {Simulation-based determination of capacity load factors for master production scheduling}, series = {Proceedings of the 15th International Conference on Simulation in Production and Logistics, October 9 - 11, 2013, Paderborn, Germany}, booktitle = {Proceedings of the 15th International Conference on Simulation in Production and Logistics, October 9 - 11, 2013, Paderborn, Germany}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:898-opus4-2610}, pages = {631 -- 640}, abstract = {This paper deals with the problem of varying capacity load factors in master production scheduling. A simulation system of a production planning and control system and of a production system is described and an approach to compute the capacity loads from the simulation results is developed. This approach is used to measure period-specific capacity load factors for master production scheduling. The measured capacity load factors vary over time and show that the common assumption of the load factors being period-independent is inappropriate. A stochastic programming model to cope with this variation is described. This model is compared to a common linear programming model for master production scheduling in a simulation experiment. The results show that the use of the measured capacity load factor scenarios improves the quality of the estimation of the capacity load factors significantly.}, subject = {PPS}, language = {en} } @article{JanssenDiabatSaueretal., author = {Janssen, Larissa and Diabat, Ali and Sauer, J{\"u}rgen and Herrmann, Frank}, title = {A stochastic micro-periodic age-based inventory replenishment policy for perishable goods}, series = {Transportation Research Part E: Logistics and Transportation}, volume = {118}, journal = {Transportation Research Part E: Logistics and Transportation}, number = {October}, publisher = {Elsevier}, doi = {10.1016/j.tre.2018.08.009}, pages = {445 -- 465}, abstract = {In this paper, we propose a micro-periodic inventory replenishment policy for quickly perishable goods with fixed and known lifetime of items, deterministic lead time, fixed given order cycle, mixed issuing policies (FIFO and LIFO), age-based stock, imperfect items and target customer service level under random demand. The inventory policy is based on time of day (morning, midday, afternoon or evening). The results of our simulation study show that the proposed micro-periodic inventory policy leads to waste reduction of 66\% as well as a partial decrease in cost compared to inventory policy with planning on a daily basis.}, subject = {Frischware}, language = {en} }