A two- goal mathematical model based on robust programming inventory-location problem with considered demand response reliability and multi level discount

In this study, a multi-objective mathematical model is developed to optimize the distribution network in a three level supply chain based on the inventory location- models with the aim of locating distribution centers. also, appropriate allocation of customers in order to maximize coverage of the demand, increasing sales through discount policies and ultimately improving the transportation system by selling the package of products agaainst individual sales is considered.On the other hand, the policy of selling pakages, Increases the total sales and their profit margin by creating appropriate price for the customrers. Due to the circumstances, each distribution center has specific reliability level which the proposed model try to maximize it. In order to make the model more realistic, some parameters have been considered under conditions of uncertainty and robust planning techniques have been used to solve it, finally, to validate the presented model, and instance according to real-world problems were solved by GAMS software. The Results are presented in details