Nonlinear pentagonal intuitionistic fuzzy number and its application in EPQ model under learning and forgetting

In this current era, the concept of nonlinearity plays an important and essential role in intuitionistic fuzzy arena. This article portrays an impression of different representation of nonlinear pentagonal intuitionistic fuzzy number (PIFN) and its classification under different scenarios. A new de-intuitification technique of non-linear PIFN is addressed in this article along with its various graphical representations. Additionally, in this paper, we have observed this by applying it in an economic production quantity model where the production is not perfect and defective items are produced which are reworked. The model is considered under learning and forgetting, where learning is considered as linear, nonlinear PIFN and crisps arena. It is observed from the numerical study that high learning effects in rework lead to decrease in production of defective item, which, besides an economic advantage, may have a positive effect on the environment. Even though forgetting has an adverse effect, the average total cost is much less than that of the basic model which ignores worker learning and forgetting. Finally, comparative and sensitivity analysis result shows the utility of this noble work.

A Fuzzy type Backlogging Production Inventory Model for Perishable Items with Time Dependent Exponential Demand Rate

Production inventory models have an important role in production planning and scheduling. In any economic production quantity (EPQ) model, the production rate is dependent on demand. In this paper we have established a production inventory model for perishable items with partial backlogging and time dependent exponential demand rate. Allowing shortage, it is partially backlogged. The unsatisfied demand is backlogged and it is considered a function of waiting time. The aim of our study is to optimizing the total profit during a given cycle. A numerical example is given in showing the applicability of the developed model.

An EPQ Model of Stock Dependent Demand Subject to Epidemic with Stochastic Lockdown Time

The model created considers the effect of the epidemic on the classical Economic Production Quality (EPQ) model for a production unit exposed to stochastic lockdown time. Expected production time is evaluated utilizing continuous probability density function. The investigation is done to decide the ideal arrangement for the production system which limits the expected total cost per unit time exposed to certain conditions. Here EPQ model is created by taking lockdown time due to epidemic as stochastic. Machine breakdown affects the manufacturer but disaster like epidemic affects the manufacturer as well as the customer (or in other words, demand). During the production uptime, demand depend upon stock and decline in selling price, but in case of disaster (epidemic) selling price has no consideration and demand depends only on stock. The model is discussed by means of a numerical example and a case study.