Implementation of nondominated sorting genetic algorithm - Ii (NSGA-II) for multiobjective optimization problems on distribution of indonesian navy warship

The high number of crimes and infraction that occurred in the Indonesian seas show the weakness of Indonesia's marine security. This is caused by the limited number of warships of the Republic of Indonesia (KRI), the lack of budget provided by the State, the wide area of the marines in Indonesia that should be secured, and the less precise decision from the Navy in determining the safety operational management of Indonesian seas. Therefore, problems in securing Indonesian seas not only in the form of a single objective problem but has become a model of multi-objective problem. So there's a way needed to solve this problem by using the best solution search using Nondominated Sorting Genetic Algorithms II (NSGA-II), this method is used because it can generate a better solution with less calculations, elitism approach, and a little more parameters division compared with simple NSGA. This study will determine the best combination of a 100 solution recommended by NSGA II in the focus of the type of the ship, speed, radar range, endurance, the area vulnerability level, geography, human resources, so it can be obtained one ideal solution in the focus of the placements composition of 27 warships to the 7 sectors in the ARMATIM area by maximizing the coverage area and minimizing the operational costs. The results of the optimization of NSGA-II with 100 iterations, it is resulted that 23 warships selected and 4 warships docking with a combination of warships in each sector (S1 = 2, S2 = 7 S3 = 6, S4 = 2, 3 = S5, S6 = 2, S7 = 1), the broader outcomes of the coverage area is 1, 722, 880 Mil², so it can increase the security of territorial ARMATIM seas around 2% from the total secured area of 1,688,765 Mil², and operational cost Rp. 4.521.548.485,- the optimization model is thus able to save about 10% of the State budget of the specified the budget of Rp. 5.000.000.000,-.