Modeling a Multi-period Transportation System for Supplier Selection and Orders Allocation Problem (case study: Parchsaz company)

The combination of transportation costs is very important in supplier decisions. In these days economic and productive firms in order to gain a competitive advantage or competitive advantage with the aim of gaining more market share in terms of controlling the cost of raw materials that directly and indirectly constitutes a major part of the cost of the product They are on their agenda. Hence, suppliers play a key role in the efficiency and effectiveness of the organization in reducing costs, quality, profitability, and flexibility. With increasing competition in the world of trade, how to supply and choose suppliers of raw materials in the supply chain is an important challenge for many organizations. Therefore, in the industry, understanding the needs of the domestic market, having to have competitive strategies in the field of assessing the quality of suppliers based on supply risks, should be able to pay attention to developing competitive opportunities by establishing business opportunities and gaining competitive advantage. Therefore, in this research, we have tried to analyze the effective measures on the assessment of the quality of suppliers by using the opinions and experiences of the experts, analyzing the relations between them and using the method of network analysis to rank the criteria and suppliers (in a case ) In the company. Therefore, in this research, 39 risk-based supply indicators were identified in the company. According to experts 'and experts' assessment, 10 indicators were selected as the final indicator. Then, according to the existing supply chain, five existing suppliers of the company were evaluated and ranked. Finally, using the mixed linear programming model, the allocation of raw materials to each of the ranked suppliers was determined.