Most commercial industries now encourage environmentally friendly or green products since they are safe for the environment in their creation, use, and disposal. Eco-friendly items serve an important role in decreasing pollution both during production and recycling. To ensure client happiness, most branded products are developed in an environmentally friendly manner. This research proposes a cost-effective manufacturing quantity model that promotes high-quality green products. To solve the model in a fuzzy sense, an extension of the lagrangian method is applied. The parameters are expressed as a fuzzy pentagonal number. Defuzzification is accomplished using the graded mean integration approach. To demonstrate the model, a numerical example is provided.
The management of manufacturing inventory is heavily weighted in favour of the company's profit and customer acquisition. Controlling the quantity of a product is a method of inspecting raw materials, work-in-progress, and finished goods in a methodical manner. Apart from inspecting for defective materials as part of quality control, the degree of pollution must also be assessed to make environmentally friendly products, as most consumers are now interested in eco-friendly commodities. This model incorporates the concept of green quality product into a fuzzy EPQ model. The product cost parameters are represented as pentagonal fuzzy numbers.
Inventory models were created with the primary goal of calculating the best quantity to order and the best timing to place the orders. In 1913, Harris  created the first economic ordering quantity (EOQ) inventory model, which includes ordering and holding expenses. By incorporating the fraction of real ideal time spent in the production process, Taft  changed this model to the economic production quantity (EPQ) model in 1918. Deterministic inventory models were developed first, then probabilistic and fuzzy inventory models were developed to deal with unpredictable scenarios. Inventory fluctuations result in shortages or surpluses, which is a very typical occurrence. To deal with such situations, Drenzer , Goyal , and Gurgani  outlined the shortage, partial backlog, and complete backlog inventory models, and Goyal fused the notion of trade credit and price measures to the inventory model in 1985. Jamal , Chang , Jaggi , and Shah  expanded these trade credit inventory models. In general, a production organisation obtains input from a variety of sources; but, if customer satisfaction declines, procurement is moved to a different source for quality control, resulting in product switching costs. In addition, the manufacturing process is not a one-step process. It is divided into three stages: pre-production, production, and post-production. All of the production-related activities in the three processes must be coordinated and closely monitored in order to produce green-quality products.
The EPQ model for green quality is incredibly practical and provides the best solution to the problem of generating green quality products. This model is quite realistic because it includes all conceivable production and quality control costs. This model differs from others in that it considers product switching costs and types. By reducing costs, this approach assists the industrial sectors in achieving the aim of consumer pleasure with green quality products. This device is also environmentally friendly because it helps to protect the environment from waste\'s harmful impacts. This model is a comprehensive model because it includes all the costs of producing green quality items.
 Nivetha Martin, P.Pandiammal(2018) Economic Production Quantity Model for Green Quality Products with Its Associated Costs of Product Switching and Three Step Production Processes, JASC: Journal of Applied Science and Computations, Volume 5, Issue 11.
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