چكيده به لاتين
The purpose of the classic economic ordering quantity inventory model is to obtain the optimal order quantity so that the total annual inventory costs is minimized. But, by increasing global concerns for reducing greenhouse gas emissions, researchers try to reduce the adverse environmental effects of organizations considering the environmental aspects in inventory control models.
In this dissertation, a mathematical model has been developed for sustainable inventory, in which simultaneous effects of environmental factors such as water pollution, air pollution and social factors such as environmental ergonomic effects, have been investigated. To this end, firstly a green EOQ model was proposed, with considering the emission of SO2 and NOx gases as air pollutants and, BOD and COD indicators in waste water as ameasure of water organic pollutants and then the ultimate and sustainable model has been introduced by adding the social aspects in the terms of the effect of SO2 emission on human health. Since the structure of the model consists of nonlinear objective function and linear constraints, the optimization solution can be approved through the second derivate of objective function and then the model can be solved based on an exact nonlinear constrained solution method. Finally, the effectiveness of the proposed model is demonstrated in a case study of pulp and paper mill, and validation of the model is examined by comparing the cost function of the proposed model with the pure economic model and the actual data. The results show that considering sustainability in inventory model plays a significant role in determining the order quantity and has led to reduction in cost function. In addition, this model reduces SO2 and NOX emissions, and also BOD and COD in waste water.
Keywords: Inventory Management, Sustainable Inventory, EOQ, BOD, Environmental Ergonomics.
