Discrete event simulation model for purchasing of marked stands , timber harvesting and transportation

Quick reactions to customers’ needs, i.e. customized production, has been a common aim of the forest industries in Finland during the past decade. At first, it was thought to be suitable only for small and medium-sized industries, but nowadays large corporations have also developed their processes to make them increasingly customerorientated. Major development projects have been launched recently, for instance by Metsäteho, the research and development unit of the Finnish Forest Industries Federation (Metsäteho, 1997). Customer-orientation involves not only production, but also timber procurement. Researchers in the field of timber procurement have raised questions as to the appropriateness of traditional approaches in organizing customized timber procurement. Simulation has been found to be a suitable research method for studying the distribution of timber flows. In this context, the first simulation model addressing the subject of quality-oriented timber supply was introduced by Tolvanen-Sikanen et al. (1995). Their model contained a large number of educated guesses because of the lack of earlier research knowledge on the subject. The theoretical model introduced in the study was stochastic and dynamic with discrete-event characteristics. The more advanced version of the model introduced in the present study includes a simulation interval of 1s and the operator can choose steps of 1 min, 1 h or a workshift of 8 h. In the model, Discrete event simulation model for purchasing of marked stands, timber harvesting and transportation