Title: The refractory emission during inspection waiting under pentagonal fuzzy number in a sustainable inventory model

Authors: P. Saranyaa; C. Sugapriya; D. Nagarajan; Kavi Kumar Jacob

Addresses: Department of Mathematics, Queen Mary's College, Chennai-04, India ' Department of Mathematics, Queen Mary's College, Chennai-04, India ' Department of Mathematics, Chettinad Institute of Technology, Chettinad Academy of Research and Education, Tamil Nadu 603103, India; Faculty of Engineering and Technology, Multimedia University, Jalan Ayer Keroh Lama,75450 Melaka, Malaysia ' Department of Mathematics and Statistics, Faculty of Applied Sciences and Technology, Universiti Tun Hussein Onn Malaysia, Campus Pagoh, 84600, Malaysia; Department of Biosciences, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Chennai, India

Abstract: Traditional inventory control problems assume that every item is of the highest quality and that the inspection procedure operates flawlessly. In this paper, the model is extended to account for imperfect items, where type I and type II errors occur during inspection, and it also expands the economic production quantity model. Under this proposed inventory system, when a batch of perfect items is finally delivered after a specialised inspection procedure, customers who received and returned imperfect items wait for their replacements. During the inspection, defective goods are transported to a rework plant via electric vehicles to be transformed into finished goods. Additionally, lower-quality items are discounted and sold quickly; a numerical example is provided, and the impact of the primary parameters on total profit is examined through a sensitivity analysis.

Keywords: waiting expenses; defuzzification; refractory; emission; kiln refractory.

DOI: 10.1504/IJMOR.2026.156083

International Journal of Mathematics in Operational Research, 2026 Vol.34 No.4, pp.401 - 450

Received: 25 May 2024
Accepted: 10 Sep 2024
Published online: 03 Sep 2026 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article