Implementation North West Corner and Stepping Stone Methods for Solving Logistical Distribution Problem in Tape Production

Abstract

Distribution is an important logistical problem in tape commodities because it has a short expiration time that requires speed and accuracy in shipping. This research collaborates implementation two methods. These are North West corner (NWC) and stepping stone. These methods make distribution scheduling model from many sources to destinations with minimum cost. This case has many steps. The first step is initial feasible solution with NWC. NWC is used this case because simple and fastest method for solving problem. NWC does not observe the cost of each shipping line in procedure. The second step revised with try and error the plan using stepping stone for optimization. In this research, collaboration these methods can reduce total cost of distribution equal to Rp.266.050. In fact, total distribution cost is Rp.317.500. After calculation, we can save cost Rp.51.450. Determination of the first source and destination in the North-west corner cell is greatly affect. If the first source and the destination have a small cost so the result is better. Stepping stone find optimization in second iteration because all of closed lanes have positive value. A positive value in repair index means that when given an allocation it will causing an increase in transportation costs. The allocation of product does not need to be changed because it will increase the cost of transportation so that the stepping stone work is completed. Percentage of differences is a formula to derive efficiency comparison between initial solution and optimal solution is 0.45%.