tailieunhanh - Multi-item fuzzy inventory model for deteriorating items with finite time-horizon and time dependent demand

This paper develops a finite time-horizon fuzzy multi-deteriorating inventory model with/without shortage, where the demand increases linearly with time. Here, the total profit is to be maximized under the limitation on investment. In this problem, total profit, total investment cost and the time-horizon are fuzzy in nature. The impreciseness in the above objective and constraint goals have been expressed by fuzzy linear/nonlinear membership functions and vagueness in time-horizon by different types of fuzzy numbers. Results are illustrated with numerical examples. | Yugoslav Journal of Operations Research 16 (2006), Number 2, 161-176 MULTI-ITEM FUZZY INVENTORY MODEL FOR DETERIORATING ITEMS WITH FINITE TIME-HORIZON AND TIME-DEPENDENT DEMAND S. KAR1, T. K. ROY2, M. MAITI3 1 Department of Engineering Science, Haldia Institute of Technology, Haldia-721 657, West Bengal, India 2 Department of Mathematics, Bengal Engineering and Science University, Howrah-711 103, West Bengal, India 3 Department of Applied Mathematics with Oceanology and Computer Programming, Vidyasagar University, Paschim Midnapore-721 102, West Bengal, India Received: March 2003 / Accepted: December 2005 Abstract: This paper develops a finite time-horizon fuzzy multi-deteriorating inventory model with/without shortage, where the demand increases linearly with time. Here, the total profit is to be maximized under the limitation on investment. In this problem, total profit, total investment cost and the time-horizon are fuzzy in nature. The impreciseness in the above objective and constraint goals have been expressed by fuzzy linear/nonlinear membership functions and vagueness in time-horizon by different types of fuzzy numbers. Results are illustrated with numerical examples. Keywords: Fuzzy inventory, deteriorating items, backlogged shortages, dynamic demand, finite time-horizon. 1. INTRODUCTION Most of the classical deterministic inventory models consider the demand rate to be constant, independent of time ‘t’. However, for certain types of inventory, particularly consumer goods (viz. food grains, oilseeds, etc.), the demand rate increases with time. In real life, the harvest of food grains is periodical. A large number of landless people of developing countries have a constant demand of food grains throughout the year. Marginal farmers or landless labourers produce food-grain in their own piece of land or in the land 162 S. Kar, . Roy, M. Maiti / Multi-Item Fuzzy Inventory Model for Deteriorating Items of their land-lords by share cropping. Due to .