Elżbieta Kasperska, dr hab inż., Silesian University of Technology, This email address is being protected from spambots. You need JavaScript enabled to view it., ul. Kaszubska 23, 44-101 Gliwice.
Elwira Mateja-Losa, dr inż., Silesian University of Technology, This email address is being protected from spambots. You need JavaScript enabled to view it., ul. Kaszubska 23, 44-101 Gliwice.
Rafał Marjasz, mgr, Silesian University of Technology, This email address is being protected from spambots. You need JavaScript enabled to view it., ul. Kaszubska 23, 44-101 Gliwice.

Abstract

The aim of our paper is to present the new results of research work on optimization and simulation for some logistic problems in the company. The System Dynamics (SD) method and the Vensim simulation language are applied in order to solve specific managerial problems described by Forrester in the model of supply chain. The historical model of Customer-Producer-Employment System by Forrester (Forrester, 1961) has not been examined with the sensitivity analysis, from the “automatic” testing perspective. Optimization experiments have not been conducted, either. It is surprising, since the model is old and widely known. The opportunities offered by the Vensim language allow us to perform such analysis. The visualization called “confidence bounds“ is used, to show the behaviour of chosen variables over a period of time. The Monte-Carlo method is applied for sampling a set of numbers from within bounded domains (distribution for each searching parameters is specified). The authors of this paper conducted numerous experiments in this scope. This paper presents their results and offers some conclusions formulated at the end.

Keywords: System Dynamics, sensitivity analysis, optimization, Vensim.