The effects of "Selling Agents"  on Multi-Objective Green Closed-Loop Supply Chain : A Case Study of Small and Medium-Sized Enterprises

Abstract

In recent decades, setting up small- and medium-sized enterprises (SMEs) and supporting them have a fundamental role in economic development. Supply chain network (SCN) design for SMEs is a strategic decision, determines their configuration, and affects their tactical and operational decisions. Different groups of customers, including customers aware of environmental issues has urged companies to compete in the design of distribution networks. This paper aims to design an integrated closed-loop supply chain (CLSC) by adding selling agents and secondary customer centers to the chain. The mathematical model of the proposed SCN is formulated as a multi-objective problem. The objectives include maximizing the profit, maximizing on-time delivery rates, and minimizing environmental issues. Transportations and production methods are affected by the objective functions, too. In the proposed network, recycling centers are located inside production centers, and collection and inspection centers are considered as part of retailers. To increase the profit and reuse the products in a backward flow, we noticed resealing markets and repackaging products. In this way, reusable products with different qualities can be sold in diverse markets with various targets. These product resale areas can be referred to as secondary customers in the model. Besides, the best suppliers are selected based on failure rate, carbon footprint, and on-time delivery. Also, the best retailer and selling agent are selected based on the simultaneous optimization of all three objective functions. The proposed model is implemented and assessed through a case study of a small and new industry of the door and window.