USING GIS-BASED DECISION SUPPORT SYSTEM FOR DETERMINING OPTIMUM ROUTING OF LOGGING TRUCKS

Abstract

Forest products are transported from landing areas to forest depots using logging trucks. Considerable amount of the total cost in the timber production in Turkey constitutes the costs of transporting forest products by logging trucks. Many alternative plans are evaluated using computer technology and optimization techniques to develop an optimum transportation planning. Network analysis, one of the operations research techniques, has been widely used to solve such transportation problems with various constraints. In recent years, computer-based techniques integrated with Geographic Information Systems (GIS) have been implemented to solve transportation problems. Network analysis-based modules of ArcGIS software such as "Network Analyst" can be also used to solve transport problems. In addition, factors that directly affect the transportation cost, such as truck size, can be evaluated in the solution process. In this study, "Network Analyst" module of ArcGIS 10.4 program was used to investigate the optimum transportation routes that minimize the total transportation cost of forest products considering three truck types. In the implementation of the system, road network data in İclaliye Forest Enterprise Chief (FEC) located in İnegöl Forest Enterprise Directorate (FED) was taken into consideration. In the model application, four forest harvesting units, three forest products (2nd quality Beech logs, 3rd quality Beech logs, and paperwood), three types of logging trucks (small, medium and large size) and a forest depot in İclaliye FEC were evaluated. The results of GIS-based decision support system showed that when using small, medium and large logging trucks, the total transportation cost was minimized at 16391 YTR, 14640 YTR and 10671 YTR, respectively. When using medium trucks instead of small trucks, the transportation cost of forest products decreased by 10.68% while the cost decreased by 34.90% when using large trucks. As a result, it was revealed that there is a close relationship between logging truck dimensions and transportation cost of forest products.