Solving the Location Routing Problem of the Central Rubber Market by Tabu Search

The central rubber market of Songkhla province is the center of the collection and distribution of rubber production from sellers to purchasers. It is considered ineffective because sellers need to deliver whole raw rubber to the market, resulting in high transport costs, especially for those who came a great distance and had little quantity. This research applied the tabu search method to solve the location selection problem of the rubber purchasing depot and manage transport routes to the market. Results found that there were 16 purchasing depots. The central rubber market had unlimited purchasing capacity while the other purchasing depots limited the quantity of rubber to 10 tons. There were five transport routes and five trucks (four ten-wheeled trucks and one ten-wheeled truck with a trailer). The total delivery costs were 53,313.89 baht per day. The answers about efficiency from the Lingo 13 program with small, medium, and large problems and real problems were not significantly statistically different at a significance level of 0.05.