The yearly throughput of the warehouse is classified into three groups including A, B and C, according to
their turnovers. Considering the turnover rates and stocking periods of the items, probabilities of (picking or
putting) the orders belonging in A, B and C classes are PA, PB and PC, respectively. The main reason of this
classification is to locate the items in the warehouse basing on the closeness to the dock. The total capacity and
yearly throughput of the warehouse, total storage spaces for each item class and the lengths of the aisles and
shelves are entered to the model as the pre-determined parameters. The notation of the parameters and variables
are shown in Table 1. Also, Fig. 1 is given to visualize some of the dimensions given in Table 1.