EOQ MODEL WITH VARIABLE DEMAND AND PARTIAL TRADE CREDIT IN FUZZY ROUGH ENVIRONMENT
MADHAB MONDAL *
Department of Mathematics, Mahishadal Girls’ College, Mahishadal, Purba-Medinipur-721628, West Bengal, India.
MANAS KUMAR MAITI
Department of Mathematics, Mahishadal Raj College, Mahishadal, Purba-Medinipur-721628, West Bengal, India.
Department of Applied Mathematics with Oceanology and Computer Programming, Vidyasagar University, Paschim-Medinipur-721102, West Bengal, India.
*Author to whom correspondence should be addressed.
In this paper an inventory model of an item is developed in a fuzzy rough environment under two level partial trade credit policy. To capture the market, supplier offers a partial credit period to its retailers, i.e., a credit period (M) is offered on a fraction (f1) of order quantity. Due to this facility, retailer also offers a partial (f2) trade credit period T0(< M) to its customers to boost the demand of the item. Demand depends on displayed inventory level, duration of customers’ credit period (T0) and amount of credit (f2) offered by the retailer. Here inventory costs are considered as fuzzy rough in nature. So average profit is also fuzzy rough in nature. As optimization in fuzzy rough environment is not well defined, expected values of average profits in different cases and subcases of the model are optimized following generalized reduced gradient (GRG) technique (using LINGO software) to find optimal decision for decision maker(DM). Different cases and subcases of the model are illustrated by numerical examples. Parametric studies due to different values of f1 and f2 are also presented.
Keywords: Inventory;, partial trade credit, fuzzy rough variable, trust measure, fuzzy rough expectation.