Determining the ship type to be built in the shipyards using fuzzy topsis and fuzzy vikor methods

Newbuilding demands of the shipyards in the shipbuilding industry alter subject to several national and international factors. These factors are based on many different reasons, in particular economic, political, strategic and social reasons. The global economic crisis has affected Turkish Shipyards, especially in recent years. A drop in orders and thus production quantities has jeopardized the shipbuilding industry. In this context, the selection of the project to be built in the shipyard is highly significant to ensure an accurate and profitable investment. Interviews with decision makers composed of senior managers working in the shipbuilding industry have contributed to this study. A selection of ship types that can be built in a Turkish shipyard by using TOPSIS and VIKOR methods in the scope of fuzzy logic have been investigated in order to designate the selection criteria and selection decision. For this purpose, ships to be built, which have been determined as a result of the interviews with the designated decision makers, have been classified as a ship type according to their technical particulars and purpose. Criteria and alternatively expressed ship types have been evaluated separately with the assistance of linguistic expressions by decision makers and then the numerical analysis of these evaluation has been completed by using triangular fuzzy numbers with TOPSIS and VIKOR methods and the results were compared. Key Words: Fuzzy logic, multi-criteria decision making method, TOPSIS, VIKOR, ship selection