Marzieh Karimi; Hasan Khademi zare; Yahia Zare Mehrjerdi; Mohammad-Bagher Fakhrzad
Abstract
Vendor-managed inventory (VMI) is a popular inventory management system that allows a vendor to access sales data and manage inventory levels for his retailers. The formulation of service level and pricing decisions are finite in the VMI model literature. The study examines how a manufacturer and its ...
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Vendor-managed inventory (VMI) is a popular inventory management system that allows a vendor to access sales data and manage inventory levels for his retailers. The formulation of service level and pricing decisions are finite in the VMI model literature. The study examines how a manufacturer and its retailer communicate with one another to optimize their net profits through modifying service level, pricing, and inventory policy in a VMI system employing a Stackelberg game. The manufacturer produces a product and distributes it to several retailers at a similar wholesale price. The retailers subsequently offer the product at retail pricing in independent marketplaces. The Cobb-Douglas demand function could characterize the demand rate in every market, which is an enhancing function of the service level, however, a reducing function of retail prices. The manufacturer selects its wholesale pricing, replenishment cycles, backorder amount, and binary variable for production capacity to optimize profit. Retailers determine retail pricing and service levels so that they may optimize their profitability. Solution procedures are evolved for finding the Stackelberg game equilibrium from which no firm is inclined to deviate from maximizing its profit. The balance benefits the manufacturer while increasing the revenues of the retailers. If the retailers are prepared to engage with the manufacturer via a cooperative contract, the equilibrium could be enhanced to the advantage of both the manufacturer and his retailers. Ultimately, a numerical example is shown, along with the appropriate sensitivity analysis, to demonstrate that. 1) In certain circumstances, the manufacturer might benefit from his leadership and monopolize the additional profit generated by the VMI system. 2) The manufacturer's profit, and later the retailers' profit, could be increased more by the cooperative contract, in comparison to the Stackelberg equilibrium; 3) Market-related parameters have a substantial impact on the net profit of any enterprise.
Mohammad Bagher Fakhrzad; Mohammad Reza Firozpour; Hasan Hosseini Nasab; Ahmad Sadegheih
Abstract
For reducing risk effects in a supply chain, the appropriate risk assessment and ranking by the use of multi-criteria decision-making methods (MCDM) is important. Failure to properly assess and rank the risks makes the supply chain less efficient and competitive. Given the existence of both qualitative ...
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For reducing risk effects in a supply chain, the appropriate risk assessment and ranking by the use of multi-criteria decision-making methods (MCDM) is important. Failure to properly assess and rank the risks makes the supply chain less efficient and competitive. Given the existence of both qualitative and quantitative criteria in a supply chain, the use of verbal preferences, given by authorities for determining the priority of qualitative factors, has higher reliability than that of the Crisp numbers. Fuzzy concept plays an important role in solving the problem of complexity of assigning quantitative fixed numbers to the values of verbal preferences. In the proposed method of this study, a comparison was made among the decision-making methods in the fuzzy environment for selecting a suitable method. To validate the proposed method, we compared it to some case studies from the literature. The results show that the proposed method has high validity and reliability in assessing the risks of a supply chain.
Mohammad Bagher Fakhrzad; Zahra Alidoosti
Abstract
In this paper, it was an attempt to be present a practical perishability inventory model. The proposed model adds using spoilage of products and variable prices within a time period to a recently published location-inventory-routing model in order to make it more realistic. Aforementioned model by integration ...
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In this paper, it was an attempt to be present a practical perishability inventory model. The proposed model adds using spoilage of products and variable prices within a time period to a recently published location-inventory-routing model in order to make it more realistic. Aforementioned model by integration of strategic, tactical and operational level decisions produces better results for supply chains. Due to the NP-hard nature of this model, a genetic algorithm with unique chromosome representation is used to achieve the optimal solution and reasonable time. Finally, the analysis is carried out to verify the effectiveness of the algorithm with and without considering the cost of spoiled products.