Simulation Model for Stock of Building Materials Developed with Crystal Ball Software Use

Abstract

The article presents a simulation model of the inventory with two variables developed using the Crystal Ball software. This model is designed for the purpose of optimization of logistics processes related to the organization of supply and storage of construction materials used in the production process. The result of the model, we get information about what reserve should be basic to the whole process took place without interference. Not always, however, it is possible to create initial stock of this size. Using the Crystal Ball software, it can be obtained information, what is the probability to avoid downtime for different levels of initial reserves. The model is based on the classical model developed by Jaworski Professor of the Warsaw University of Technology. In the new model two variables will be considered. The first variable is the amount of depreciation. In the classical model it is described discreetly. Based on historical data, determines the probability with which will be observed the consumption plan and the probability of default and excess of norm of consumption of this material. The second variable take into account the amount of planned delivery. In the same way as in the case of the size of the depreciation in the classical model this variable was described discreetly. As before, the author recommends a definition based on historical data probability of compliance with the required value of delivery probability and delivery more or less than planned. In the presented model we also consider the possibility of describing random variables using other than the discrete graphics and the empirical probabilities. This procedure allows for the approximation of modelling methods for people who do not have the appropriate set of historical data and would like to use it to minimize the risk of organizational problems. The article shows what results are achieved through the use of the software Crystal Ball, and how they can be used in the organization of the construction investment process.