NP{hard cases of the single{item capacitated lot{sizing problem have been the topic of extensive research and continue to receive considerable attention. However, surprisingly few theoretical results have been published on approximation methods for these problems. To the best of our knowledge, until now no polynomial approximation method is known which produces solutions with a relative deviati...

This study examines the optimal run time for the economic manufacturing quantity (EMQ) model with failure-in-work, backlogging, and random breakdown happening in stock-piling time. A recent article by Chiu and Chiu [Mathematical modeling for production system with backlogging and failure in repair, Journal of Scientific & Industrial Research, 65 (2006) 499-506] investigated optimal lot-size for...

Demand considered in most of the classical inventory models is constant, while in most of the practical cases the demand changes with time. In this article, an inventory model is developed with time dependent two parameter weibull demand rate whose deterioration rate increases with time. Each cycle has shortages, which have been partially backlogged to suit present day competition in the market...

In this paper we have developed a two echelon supply chain production inventory model for deteriorating products having stock dependent demand under inflationary environment. This model is developed for finite time horizon. The shortages are allowed and partially backlogged. To make this study close to reality the production rate is assumed to be a function of demand rate. A numerical example a...

In this article, an inventory model is developed to deal with the impreciseness present in the market demand and the various cost parameters. The presented model is developed in crisp and fuzzy environments. Signed distance method is used for defuzzification. In most of the classical models, constant demand rate is considered. But in practice purchasing deeds of the customers is affected by the...