Single item inventory control under periodic review and a minimum order quantity

In this paper we study a periodic review single item single stage inventory system with stochastic demand. In each time period the system must order none or at least as much as a minimum order quantity

Effect of modeling fixed cost in a serial inventory system with periodic review

We study a two-echelon serial inventory system with stochastic demand. We assume that fixed ordering costs are charged only when an order initiates a non-zero shipment. The system is centrally controlled and ordering decisions are based on echelon base stock policies. The review period of the upper echelon is an integer multiple of the review period of the lower echelon. We derive an exact analytical expression for the objective function. From this expression, we determine optimal base stock levels and review periods. Through a numerical study we show that there may be several combinations of optimal review periods and that under high fixed ordering costs both stockpoints have the same order frequency. In addition, we identify parameter settings under which the system behaves like a PUSH-system, where the upstream stockpoint never holds any stock. Generally, in literature fixed ordering costs are charged at every review moment, even if no shipment results due to zero upstream stock. We test the impact of this simplifying assumption and illustrate when it is justified

Logística reversa numa empresa de laminação de vidros: um estudo de caso Reverse logistics in a glass lamination industry: a case study

Este trabalho apresenta uma aplicação da Logística Reversa numa empresa multinacional que atua na área de laminação de vidros no Brasil. Na empresa estudada, a sucata gerada pelos seus clientes pode ser usada para realimentar o seu processo de produção. Inicialmente, são discutidos os principais aspectos relacionados ao tema, tais como, definição de Logística Reversa, ciclo de vida do produto, motivos e destinos do retorno, além dos fatores que influenciam a eficiência de um processo de Logística Reversa. A seguir, ilustradas pelo estudo de caso, são apresentadas e comentadas as etapas para uma implementação de um sistema de Logística Reversa ser bem sucedida. Finalmente, comentam-se as dificuldades, ganhos e vantagens competitivas obtidas por empresas que adotaram soluções da Logística Reversa, em particular na empresa em que o estudo de caso foi desenvolvido.<br>This paper introduces a Reverse Logistics application in a multinational plastic film industry in Brazil, where the waste generated by its customers can reload the production process. Firstly, the main features concerning the theme and the factors that influence an efficient process of Reverse Logistics are discussed. Afterwards, using a case study, the steps focusing on the implementation of Reverse Logistics, which were successful in a company, are introduced and discussed. Finally, the difficulties, gains and competitive advantages obtained by the companies that have adopted Reverse Logistic solutions, particularly the company where the case study was developed, are commented upon