in the fundamental production inventory model, in order to solve the economic production quantity (epq) we always fix both the demand quantity and the production quantity per day. but, in the real situation, both of them probably will have little disturbances every day. therefore, we should fuzzify both of them to solve the economic production quantity (q*) per cycle. using α-cut for defuzzific...

This paper develops an inventory model for non deteriorating items with time dependent demand rate of production with constant inflation rate. In this model shortages are not allowed, the effect of inflation rate and delay in payments are discussed. In the study mathematical models are also derived under two different cases, i.e. Case-I the credit period is less than or equal to the cycle time ...

This paper deals with a two-warehouse inventory model for deteriorating items with time dependent demand and partial backlogging under inflation. It is assumed that deterioration of items follows two-parameter Weibull distribution and demand rate varies exponentially with time. Shortages are allowed and partial backlogging depends on waiting time of next replenishment. A numerical example is pr...

 The paper considers an integrated production, inspection, preventive maintenance, and inventory problem and determines the optimal inspection interval, inspection frequency, and production quantity yielding the maximum unit expected profit in an imperfect production process with inspection time and reworking. When the process in an out-of-control state produces a certain percentage of non-con...

This investigation presents an economic production quantity (EPQ) model for deteriorating items with stock-dependent demand and shortages. It is assumed that a constant fraction of the on-hand inventory deteriorates and demand rate depends upon the amount of the stock level. Expression for various optimal indices as well as cost analysis are provided. By taking numerical illustration, sensitivi...

In practice, manufacturing systems are never perfect and may have low quality outputs. Therefore, different decisions such as reprocessing, sale at lower prices or diminishing are made according to industry and market. This paper investigates the importance of supply chain coordination through developing two models in centralized decision-making for an imperfect quality manufacturing system wit...

This paper discusses why the selection of a finite planning horizon is preferable to an infinite one for a replenishment policy of production inventory models. In a production inventory model, the production rate is dependent on both the demand rate and the inventory level. When there is an exponentially decreasing demand, the application of an infinite planning horizon model is not suitable. T...

As organizations move from creating plans for individual production lines to entire supply chains it is increasingly important to recognize that planning decisions impact the quality of parts and products and, consequently, the production output. The consideration of product characteristics, e.g., fixed or uncertain lifetimes, is vital to production systems dealing with products that deteriorat...

This paper investigates a production inventory model under classical EPQ framework with the assumption that customer demand during stock-out period is affected by accumulated back-orders. The backlog rate not fixed; instead, assumed to decrease proportionally existing which thereby approximated piecewise constant function. Deteriorating items are taken into consideration in this work. For bette...