Interactive Simulatior of Western Logging Systems

Abstract

The use of simulators to model harvesting systems has been restricted by both 1) the number of timber harvesting systems available to be analyzed by the simulator and 2) the level of simulation expertise of the analyst. This research is focused on the development of a simulator of multiple timber harvesting systems. The simulation models are programmed in ProModel, a discrete event simulation language. The simulator is manipulated from Excel environment through Visual Basic for Applications interfaces, allowing the analyst to modify system variables related to the forest and the harvesting machines without direct manipulation of the simulation models. The development of a bucking algorithm allows the estimation of system production and machine production rates by species and product types. The combined influence of the selected statistical distributions and the silvicultural prescription can have a significant influence on the variability and average values of simulation results. The entity driven modeling approach of machine driven processes requires adjustments that limit the flexibility of the simulator. The use of object-oriented interfaces was reasonably successful, but was restricted to the manipulation of system variables. Manipulation of resources, entities, locations, and subroutines is limited to ProModel environment.