Vendor Managed Inventory is a well-known vendor-retailer coordination approach in supply chain management where the vendor manages inventory of the retailer and determines the order interval and order quantity for the retailer. To consider practical situation, the upper limit of inventory for the retailer is set. If the inventory level for the retailer exceeds the upper limit, then the penalty cost is charged to the retailer. Furthermore, maximum allowable inventory level is set for the vendor to prevent the vendor from keeping much inventory. Single-vendor multi-retailer supply chain model with upper limit of inventory for vendor and retailers is studied. All the retailers’ are assumed to have the common cycle time, and a vendor manages retailers’ inventory and replenishes products. The mathematical formulation is introduced to minimize the total cost including the penalty cost violating the upper limit of inventory for retailers with the constraint of maximum allowable inventory level. The solution procedure based on Karush-Kuhn-Tucker (KKT) conditions is derived. KKT conditions are often applied to find an optimal solution of nonlinear programming problem with constraints. An illustrative example is used to show the application of the proposed solution procedure. Furthermore, sensitivity analysis is done to find out the relationship between maximum allowable inventory level and other values such as order quantity, the number of shipment, vendor’s cost, retailer’s cost, and total cost. As maximum allowable inventory level decreases, the number of shipment decreases but total cost increases. Order quantity has the trend of decline and is affected by the number of shipment.
In order to remove the inefficient cost occurred among companies, the cooperation among companies are required. The single vendor-single buyer integrated model is often studied for that purpose. Buyer’s demand follows normal distribution, and vendor’s inventory policy use a continuous inventory review policy. If buyer places order, then vendor begins to make products and transfer those products to the buyer several times. In real situation, the size of company’s warehouse is restricted, space limit constraint is considered. There are three approaches for the single vendor-single buyer integrated model with space limit: equal batch shipment approach, increasing batch shipment approach, and mixed approach. In this paper, these approaches are compared one another and we discuss about the advantages and disadvantages of these approaches.
Unlike most researches that focus on single manufacturer or single buyer, this research studies the cooperation policy for two participants of supply chain such as single vendor and single buyer. Especially, this paper deals with single vendor-single buyer integrated-production inventory problem. If the buyer orders products, then the vendor will start to make products and then the products will be shipped from the vendor to the buyer many times. The buyer is supposed to order again when the buyer’s inventory level hits reorder point during the last shipment and this cycle keeps repeated. The buyer uses continuous review inventory policy and customer’s demand is assumed to be probabilistic. The contribution of this paper is to present a mixed approach and derive its cost function. The existing policy assumes that the size of shipping batch from single vendor to single buyer is increasing, called Type 1, or constant, called Type 2. In mixed approach, the size of shipping batch is increasing at the beginning part of the cycle, and then its size is constant at the ending part of the cycle. The number of shipping for Type 1 and Type 2 in a cycle in mixed approach is determined to minimize total cost. The relationship between parameters, for example, the holding cost per product, the set up cost per order, and the shortage cost per item and decision variables such as order quantity, safety factor, the number of shipments, and shipment increasing factor is figured out via sensitivity analysis. Finally, it is statistically proved that the mixed approach is superior to the existing approaches.
This paper considers one vendor-one buyer integrated-production inventory problem. If the buyer orders products, then the vendor will start to make products and then the products will be shipped from the vendor to the buyer many times. The buyer is supposed to order again when the buyer’s inventory level hits reorder point during the last shipment and this cycle keeps repeated. Buyer uses continuous review inventory policy and customer’s demand is assumed to be probabilistic. The contribution of this paper is to develop a new approach for one-vendor-one-buyer integrated production-inventory problem.
The CEO leadership and employee’s concerning and participation to quality management innovation activity is critical factor for improving the business performance. This empirical study is aims to find that whether the quality management activity is significant or not in the automotive parts suppliers. To perform this research, we distributed 250 sheets totally, and withdraw 194 sheets. We analysed 169 sheets that we could use for this research using SPSS 18.0 and AMOS 18.0. We had the results that CEO leadership is significantly positive effects on the employees’s participation to quality management. And the result of process improvement have positively effective and significant effects on the product improvement result and business performance of firms.
This paper is to analyze an integrated production and inventory model in a single-vendor multi-buyer supply chain. The vendor is defined as the manufacturer and the buyers as the retailers. The product that the manufacturer produces is supplied to the retailers with constant periodic time interval. The production rate of the manufacturer is constant for the time. The demand of the retailers is constant for the time. The cycle time of the vendor is defined as the elapsed time from the start of the production to the start of the next production, while the cycle times of the buyer as the elapsed time between the adjacent supply times from the vendor to the buyer. The cycle times of the vendor and the buyers that minimizes the total cost in a supply chain are analyzed. The cost factors are the production setup cost and the inventory holding cost of the manufacturer, the ordering cost and the inventory holding cost of the retailers. The cycle time of the vendor is investigated through the cycle time that satisfies economic production quantity with the production setup cost and the inventory holding cost of the manufacturer. An integrated production and inventory model is formulated, and an algorithm is developed. An numerical example is presented to explain the algorithm. The solution of the algorithm for the numerical examples is compared with that of genetic algorithm. Numerical example shows that the vendor and the buyers can save cost by integrated decision making.
The purpose of this study was to investigate the relationship between working environment and quality of life of fashion vendor company workers by using working environment variables such as job stress, job burnout, job satisfaction, and turnover intention. Preliminary test was conducted by interviewing fashion vendor company workers in order to find out factors that were more suitable for their working environment. Main survey was conducted to 200 fashion vendor company workers and 194 responses were analyzed. The results of correlation analysis showed that job stress, job burnout, job satisfaction, turnover intention, and factors of quality of life had significant relationships. Boss stress, role stress, achivement decrease, and personal condition satisfaction showed a significant relationship with turnover intention. The results of path analysis showed that job stress had a positive relationship with job burnout and job burnout had a negative relationship with job satisfaction. Both job stress and job burnout had a positive relationship with turnover intention, whereas job satisfaction had a negative relationship with turnover intention. Also, the results showed that job burnout and turnover intention had a negative relationship with quality of life of fashion vendor company workers, whereas job satisfaction had a positive relationship with quality of life of fashion vendor company workers.
This paper is to analyze the cycle time of the vendor in a single-vendor multi-buyers supply chain. The vendor is the manufacturer and the buyers are the retailers. The cycle time of the vendor is the elapse time from the beginning time of the production to the beginning time of the next production. The cycle time of the vendor that minimizes the total cost in a supply chain is analyzed. The cost factors are the production setup cost and the inventory holding cost of the vendor, the ordering cost and the inventory holding cost of the retailers. The cycle times of the vendor obtained with the costs of the vendor is compared with those obtained with the costs of the vendor and the retailers. Various numerical examples are tested if the cycle times of the vendor for both methods are the same.
A vendor selection problem consists of two different kinds of decision making. First one is to choose the best suppliers among all possible suppliers and the next is to allocate the optimal quantities of orders among the selected vendors. ln this study, a
In this paper, we consider a single-vendor single-buyer supply chain problem where a single vendor order raw materials from its supplier, then using its manufacturing processes converts the raw materials to finished goods in order to deliver finished good
A vendor selection problem consists of two different kinds of decision making. First one is to choose the best suppliers among all possible suppliers and the next is to allocate the optimal quantities of orders among the selected vendors. In this study, an integration of the technique for order preference by similarity to ideal solution (TOPSIS) and a multi-objective mixed integer programming (MOMIP) is developed to account for all qualitative and quantitative factors which are used to evaluate and choose the best group of vendors and to decide the optimal order quantity for each vendor. A solution methodology for the vendor selection model of multiple-vendor, multiple-item with multiple decision criteria and in respect to finite vendor capacity is presented.
The inventory routing problem (IRP) is an important area of Supply Chain Management. The objective function of IRP is the sum of transportation cost and inventory cost. We propose an Artificial Immune System(AIS) to solve the IRP. AIS is one of natural computing algorithm. An hyper mutation and an vaccine operator are introduced in our research. Computation results show that the hyper mutation is useful to improve the solution quality and the vaccine is useful to reduce the calculation time.
VMI(Vendor Managed Inventory)가 사회적인 관심사로 부각되고, 전 부분으로 확산 되고 있음에도 불구하고 VMI의 도입적용에 관한 연구 및 문헌자료는 찾아보기 힘들 정도로 부족한 실정이다. VMI에 관한 연구의 대부분이 재고기법에 관한 응용연구에 편중되고, 공급체인상의 하부기능으로 일부 언급되었을 뿐, 공급체인상의 프로세스를 중심으로 VMI의 실증연구가 이루어진 자료는 전무한 실정이다. 이러한 상황에서 VMI의 도입 구축 프로젝트추진을 계기로 VMI의 적용에 따른 물류 프로세스 개선에 관한 연구를 하였다.
Recently, Vendor Managed Inventory(VMI) has been commonly recognized as one of the supply chain application that delivers clear value to the sectors of electic & electronic components. VMI is a process in which a supplier generates orders for its distributor based on demand information sent by the distributor. VMI is providing the benefits of smoother demand, lower inventories(work in process, safety stock) and reduced costs. This study focused on improvement of safety level inventory efficiency by VMI. The results indicated that VMI allowed the company to serve its customers more surely and efficiently.
Purpose – The main feature of this study is understanding of the vendor’s opportunism on the collaboration context between buyer and vendor from the buyer’s viewpoint with resource dependence theory. A number of studies on opportunism have focused on opportunistic definitions and its theoretical studies. Other researches emphasize the importance of governance in ways that reduce opportunism. We think that this research could be filled with the lack of previous studies. Research design, data, and methodology – In order to accomplish research purpose, four hypotheses have been established based on the framework of resource dependence theory and previous studies. And we have used 599 survey data jointly collected by Korea Productivity Center and the Ministry of Trade, Industry and Energy. To verify these hypothesis, we have conducted multiple regression analysis with SPSS 23.0. Results – The vendor 's opportunism decreases as mutual trust with buyer becomes higher. However, as the degree of dependence of buyers on vendor resources increases, vendor’s opportunism increases. And monitoring vendor's capacity has a moderating effect with buyer resource dependency to vendor's opportunism. Conclusions – This study suggest there are two options to decrease vendor's opportunism. Increasing mutual trust or decrease dependence on vendor's resources. Also, monitoring suppler's capacity could be effective when vendor's resource dependence is high.