Analysis of Sugarcane Stems Transportation Process from Farm to Factory using Queuing Theory

Different reasons can be listed to explain long delays in milling of the harvested sugarcane in sugarcane agroindustry units:  factory's downtime, failures of tractors in waiting line, accident due to crowd of tractors in yard, and shift change that creates quite long queues. To understand the dimensions of this problem, queuing theory was used in the basis of (1) to obtain a supply of sugarcane queuing system (2) to obtain a proper queuing system in the supply of sugarcane (3) to obtain a minimal cost to the queuing system in the supply of sugarcane. The research was carried out in an agroindustrial sugarcane in Khuzestan province. The required data related to arrival and service times of tractors were collected in 2016. Data analysis were performed according to the queuing models in the agroindustry unit. Based on preliminary observations, queuing system of agroindustry unit was a single channel model with one server, so this study was carried out by M/M/1 model. The results showed that average waiting time of queuing system with a single channel in servicing was 2 hours and 6 minutes, so in 60% of cases, the queue length will be longer than what servicing can respond. Calculations indicated that the costs could be minimized by increasing service levels up to 7.3%. The long queue in the queuing system can be improved by increasing service levels including: following preventive maintenance rather than corrective maintenance, using hidden factory, using spare parts, and expanding area for waiting line, accordingly