Creation of mathematical models for raw materials to be assigned to storage shelves with the multi criteria decision making method: Application in a food company

The topic is interested in this paper is to assign the raw materials in maximum amounts to the shelf-space where a warehouseman must decide which shelf space to assign to the raw materials. When making this decision, he/she has to consider that space is limited, all raw materials have not the same important level among themselves, at the same time they have different amount of stocks and size of pallet etc. In existing workings, the shelf sizes and pallets are calculated by an one-dimensional space or the standart measures. But, in real situation shelf and pallet sizes have different measure in terms of width, height and depth. In order to assign maximum amounts to shelves, all constraints above are taken into consideration. The mathematical model is proposed in which all situations in practice. The model can show that the optimum amounts are assigned to shelves according to their degree of importance. To do this, the degree of importance is determined by annual consumption amount, cost etc. The model is formed, has an objective function with an importance coefficients. ABC analysis was used in order to determine the raw materials in A class which are important for firm. The importance coefficients of the raw materials were determined by the multi-criteria decision making method and the purpose function of the linear model was created. In this study, it was seen that the 4 experts whose opinions were taken decided to classify the raw materials according to their expertise. For example, for the analyst, the "Analysis" criterion is of the greatest importance, on the other hand, according to the warehouse official, "Access to raw material" criterion is of the greatest importance. Fuzzy Analytical Network Process method was used to create a model without ignoring all these different views and the relationships between the criteria determined for the raw materials. The various numerical analyzes were made. Firstly, the main criteria were determined so that 4 different experts can classify the raw materials. The criterion weights determined as a result of the combining process are used as the coefficients of the decision variables in the objective function of the mathematical model. The constraint equations of the mathematical model are formed according to the changing capacities of the cells of the block rack systems and the maximum-minimum stock values of the raw materials. As a result, the warehouse officer was directed by determining how much of which raw material should be kept on which shelf. Keywords: ABC Analysis, MCDM, Shelf Assignment Problem, Mathematical Model, Optimization