Managing supply chain operations in a reliable manner is a significant concern for decision-makers in competitive industries. In recent years consumers and legislation have been pushing companies to design their activities in such a way as to reduce negative environmental impacts more and more. It is therefore important to examine the optimization of total supply chain costs and environmental impacts together. However, because of the recycling of deteriorated products, the environmental impacts of deteriorating items are more significant than those of non-deteriorating ones. The subject of supply chain of deteriorating products, simultaneously considering costs and environment has gained attention in the academia and from the industry. Particularly for deteriorating and seasonal products, such as fresh produce, the issues of timely supply and disposal of the deteriorated products are of high concerns. The objective of this paper is to develop multi objective mathematical model and to propose a new replenishment policy in a centralized supply chain for deteriorating products. In this model, the manufacturer produces a new product and delivers it to a distant market, and then the distributor buys the product and sells it to the end consumers. This study presents a new mathematical model of the location-routing problem (LRP) of facilities in supply chain network (SCN) for deteriorating products through taking environmental considerations, cost, delivery time and customer satisfaction into account across the entire network and customer satisfaction. In order to solve the model, the combination of the two red deer algorithm (RDA) and annealing simulation (AS) was proposed. We then perform the network optimization in SCN and provide some managerial insights. Finally, more promising directions are suggested for future research. Manuscript profile

هدف این پژوهش ، طراحی یک مدل ریاضی چند هدفه به در راستای بهینه سازی زنجیره تامین چهار سطحی کالاهای فاسد شدنی با استفاده از الگوریتم فرا ابتکاری هیبرید با عنایت به زمان تدارک، هزینه و رضایت مشتری است. زنجیره‌های تامین چهار سطحی مواد غذایی فاسدشدنی به دلیل تغییرات مداوم و قابل توجه در کیفیت محصولات غذایی در سراسر زنجیره تا زمان مصرف نهایی جزو زنجیره‌های تامین محصولات متفاوت محسوب می‌گردد. در این تحقیق، مدل ریاضی برای مسئله مکانیابی- مسیریابی تسهیلات در یک زنجیره تامین چهار سطحی برای محصولات فاسد شدنی با رویکرد بهینه سازی همزمان هزینه‌های کل زنجیره تامین، زمان تحویل سفارشات، انتشار آلاینده‌ها و سطح رضایت مشتریان ارائه می‌گردد. برای سنجش اعتبار تحقیق، مدل ریاضی در صنایع غذایی بهشهر مورد مطالعه قرار گرفته و مسئله پژوهش در قالب یک مدل چندهدفه برنامه‌ریزی غیرخطی عدد صحیح مختلط ارائه و برای حل آن، از ترکیب دو الگوریتم تبرید و گوزن قرمز استفاده شده است. نتایج الگوریتم پیشنهادی در یک مطالعه موردی حل و نتایج حاصل از عملکرد الگوریتم بر اساس شاخص‌های استاندارد بررسی شده و در نهایت نتایج محاسباتی، نشانگر کارایی الگوریتم برای طیف وسیعی از مسائل با اندازه‌های متفاوت است. Manuscript profile

During the last three decades, the concept of integrated decision making in the supply chain becomes one of the essential aspects of supply chain management (SCM). This concept explores the interdependence between facility location, flow allocation between facilities, transportation system structure, and inventory control system. This study presents a new form of the location-routing problem of facilities under uncertainty in a supply chain network for deteriorating items through taking environmental considerations, cost, and procurement time and customer satisfaction into account, to simultaneously minimize total system costs, maximal delivery time and emissions across the entire network and maximize customer satisfaction. The research problem is formulated in a mixed-integer nonlinear multi-objective programming. In order to solve the model, the combination of the two Benders decomposition algorithm and Lagrange multiplier liberalization, as well as the combination of red deer algorithm and annealing simulation, was proposed. For validation, the results of the proposed algorithm in different size examples are compared with the results of the exact method solution by MATLAB software. The mean error of the proposed algorithm for the objective function is less than 4% compared to the exact method in solving the sample problems. Besides, the results of the algorithm performance are investigated based on standard indices. The computational results show the efficiency of the algorithm for a wide range of problems with different sizes. The location decisions are interdependent, and the process of determining the optimal values of these variables interact together, which can lead to an optimal system. Manuscript profile