• 한국경영과학회지
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• 제26권3호
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• pp.105-117
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• 2001

This paper models supply uncertainty in the dynamic Newsboy problem context. The system consists of one supplier and one retailer who places an order to the supplier every period to meet stochastic demand. Supply uncertainty is modeled as the uncertainty in quantities delivered by the supplier. That is, the supplier delivers exactly the amount ordered by the retailer with probability of $\beta$ and the amount minus K with probability of (1-$\beta$). We formulate the problem as a dynamic programming problem and prove that retailer’s optimal replenishment policy is a stationary base-stock policy. Through a numerical study, we found that the cost increase due to supply uncertainty is significant and that the costs increase more rapidly as supply uncertainty increases. We also identified the effects of various system parameters. One of the interesting results is that as retailer’s demand uncertainty, the other uncertainty in our model, increases, the cost increase due to supply uncertainty becomes less significant.

• 대한안전경영과학회지
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• 제8권3호
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• pp.115-123
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• 2006

The main focus of this study is to investigate the performance of a clark-scarf type multi-echelon serial supply chain operating with a base-stock policy and to optimize the inventory levels in the supply chains so as to minimize the systemwide total inventory cost, comprising holding and backorder costs as all the nodes in the supply chain. The source of supply of raw materials to the most upstream node, namely supplier, is assumed to have an infinite raw material availability. Retailer faces random customer demand, which is assumed to be stationary and normally distributed. If the demand exceeds on-hand inventory, the excess demand is backlogged. Using the echelon stock and demand quantile concepts and an efficient simulation technique, we derive near optimal inventory policy. Additionally we discuss the derived results through the extensive experiments for different supply chain settings.

• 경영과학
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• 제19권1호
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• pp.107-116
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• 2002

A major challenge to supply chain managers is how to control inventories and costs along the supply chain while maximizing customer service Performance. In the literature, although the optimal management of inventory along the supply chain has received considerable attention during the past decades, the attention has been mainly given to multi-echelon control policies. A prerequisite for applying these policies is full information transparency in the supply chain, which is hard to accomplish in practice because it may require major organizational chanties. In the case that a decentralized control (local (R, S) policy) should be used at each location in multi-stave distribution systems, this paper presents the coordinating approach of determining the best policy which satisfies predetermined target customer service levels and minimizes the mean physical stock along the system.

• 산업공학
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• 제23권4호
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• pp.327-336
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• 2010

We consider a supply chain consisting of a make-to-order manufacturer and N component suppliers and study the impacts of the number of suppliers on component inventory management. The manufacturer has full information and continuously observes the state of both component inventory level and customer backorders. Based on this information, the manufacturer determines whether or not to place a component purchasing order to a supplier among N suppliers even though some orders are in process by other suppliers. The goal of this paper is to numerically identify the manufacturer's purchasing policy which minimizes the total supply chain cost and the best choice of N. Our model contributes to the current literature in that the problem of simultaneously considering multiple outstanding orders and incorporating order setup cost into the model has not been covered yet. From numerical experiment, we investigate how much the policy with N suppliers can contribute to reducing the supply cost compared to the policy with a single supplier.

• 수산경영론집
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• 제44권3호
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• pp.61-76
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• 2013

This study is aimed to present measures for stable supply of fishmeal and to develop fish farming into a food industry and an export industry. The study analyzed current domestic and international supply and demand for fishmeal and suggested future prospects. The results of the study suggested the basic directions for the stable supply of fishmeal in Korea as follows: first, stable securing of fishmeal importers and establishment of the supply and demand monitoring system; second, policies to boost using of compound feeds and expansion of relevant fishmeal use; third, higher competitiveness of fishmeal and compound feeds through selective and intensive R&D investments. Based on the basic directions, the paper suggested implementation measures such as strengthening of cooperations with fishmeal suppliers abroad, expansion of overseas local market entrance, diversification of fishmeal trading countries, revision of relevant laws and polices on the fishmeal and feeds, organization of domestic fishmeal, promotion of group purchase, improvement of domestic fish meal quality, development of fish meal alternatives, etc.

• 한국경영과학회지
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• 제29권3호
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• pp.111-127
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• 2004

We consider a supply chain model with a make-to-order production facility and a single supplier. The model we treat here is a special case of a two-echelon inventory model. Unlike classical two-echelon systems, the demand process at the supplier is affected by production process at the production facility as well as customer order arrival process. In this paper, we address that how the demand variability impacts on the optimal replenishment policy. To this end, we incorporate Erlang and phase-type demand distributions into the model. Formulating the model as a Markov decision problem, we investigate the structure of the optimal replenishment policy. We also implement a sensitivity analysis on the optimal policy and establish its monotonicity with respect to system cost parameters.

• 기술혁신연구
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• 제4권1호
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• pp.185-207
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• 1996

It is frequently pointed out that the Korean economy, with its scarce natural resources, would never have been able to achieve current levels of economic development without the massive provision of well-educated, hardworking human resources. Throughout the industrialization process ,full-fledged deployment and mobilization of qualified human resources have been the foundation to industrial policy and S&T policy. This paper describes the development of S&T human resources in Korea using various statistics including educational enrollment rates, unemployment rates, the allocation of researchers and R&D expenditures among sectors of performance, educational composition of employment within and across industries, technical human resource shortage rates, relative wage levels of SMEs, and composition of labor force by age-group and gender. While analyzing S&T human resources development, this paper discusses issues such as the mismatched demand and supply of skill and knowledge levels of the highly educated, the unbalanced distribution of S&T human resources between sectors, and the low utilization of the female and aged labor force. This paper suggests that the policy maker applies a hybrid of quantitative and qualitative policies to reduce the mismatches of supply and demand of skill and knowledge levels for each labor market categorized according to supply side.

• East Asian Economic Review
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• 제22권2호
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• pp.217-239
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• 2018

This paper tests empirically the causal relationship between bank loans and the monetary base before and after the adoption of inflation targeting in seven Asia-Pacific countries using Toda-Yamamoto Granger non causality test and the bootstrap test for causality. The most striking finding is that the bank loans Granger cause the monetary base during the inflation targeting period in all the countries, except Japan, which was under the influence of the quantitative easing, whereas the causality appeared diverse before the inflation targeting regime. This result implies the need for the policy makers to take the endogenous nature of the money supply into account in the modern economy.

• 대한예방한의학회지
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• 제8권2호
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• pp.1-12
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• 2004

This paper estimated the demand and supply of physicians for oriental medicine for the period of $2009{\sim}2019$. Two equation models were used in the estimation of manpower. In 2004, the total number of physicians of oriental medicine was amounted to 13,662 registered and 10,532 available in clinical practice, respectively. According to estimates in the study, overall excess supply of physician manpower in oriental medicine was expected in the period, such as $5,300{\sim}5,700$ persons in 2009 and $900{\sim}1,700$ persons in 2019. However, the excess supply would be mitigated after 2019 mainly due to an increase in demand for oriental medical services. Specially, opening medical service market to overseas could be an exogenous variable in physician supply. An alternative manpower policy for oriental medical doctors is needed in a way of controlling oversupply.

• 한국경영과학회지
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• 제31권1호
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• pp.25-36
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• 2006

Consider a supply chain in which a vendor supplies a product to a buyer. We assume that the buyer's and vendor's inventory cost structures are different, resulting in differences in inventory order/delivery cycle times. Here, if one party insists on its individually optimal order/delivery quantity, the other party will suffer from mismatches in cycle times. Under this scenario, coordination contracts that make use of either a Net Term/Two parts Term Trade Credit or a Quantity Discount are designed to align individually optimal order Quantities. We compare and analyze the perform ances of these contracts. The focus of the comparison is the ability of contracts to generate a lower cost for the supply chain. We show that a Trade Credit policy can be effectively used to coordinate a supply chain. In many cases it will result in a lower supply chain cost compared to that achieved by using a Quantitative Discount policy.