• Journal of applied mathematics & informatics
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• 제6권2호
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• pp.539-552
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• 1999

An order-level inventory model for a perishable product with a time-dependent demand is developed for a fixed planning pe-riod allowing backlogging in all cycles within the said period. The market demand is assumed to decrease exponentially as time elapses. The average system cost is derived and its optimization procedure is illustrated with a numerical example. Sensitivity of the optimal so-lution to changes in the values of different parameters of the system is also analysed.

• 산업기술연구
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• 제21권B호
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• pp.37-44
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• 2001

Distribution System is considered as the most important part of SCM when the satisfaction of customer demand is considered. This paper focus on the backorder policies for stockout which is occurred in each regional distribution center of two-echelon distribution system facing stochastic demand process. Four concepts for the efficient system operation are suggested. First, at least 30% reduction of stockout is achieved by introduction of 50/25 allocation policy to distribution system. Second, transportation cost and lead-time of backorder are decreased by allowance of internal supply between regional distribution centers. Third, the frequency of emergency supply is minimized by application of Ship-up-to- expected-demand backorder policies. Finally we suggest several effective rules to select multi-internal suppliers. Simulation tests show the efficiency of our backorder policies and enhancement of customer service level.

• 품질경영학회지
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• 제14권1호
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• pp.47-52
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• 1986

Slow-moving items whose cost is so high and/or whose demand is so low the optimal policy is to place a reorder immediately whenever a demand occurs. This is a continuous review (S-1,S) inventory policy which means that whenever a demand for an arbitrary number of units is accepted, a reorder is placed immediately for that number of units. This paper show optimal inventory level ($S^*$) when arrivals tend to get discouraged and recommend practical difficulties of deciding stockholding policy of slow-moving items. Also, a simple numerical example is provided.

• 국토계획
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• 제53권7호
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• pp.67-86
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• 2018

This paper attempted to analyze impacts of transition in electricity generation system on a national economy and environmental level in Korea using a recursive computable general equilibrium(CGE) model. In particular, the paper presented a hybrid model combining the top-down CGE model with the bottom-up model which describes the structure of electricity production in detail. The impacts were analyzed by two policy scenarios base on the basic plan for electricity supply and demand proposed by the Korean government. As a result, the paper specifically showed that there exists a trade-off relationship in the policy-making between economic efficiency and environmental level. The paper also suggested that the transition in electricity generation system should be done more gradually and carefully.

• 간호행정학회지
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• 제8권4호
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• pp.615-632
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• 2002

Purpose : this study was to project demand of home nursing care in Korea for contributing toward the distribution of home nursing care resource. Method : demand of home nursing care is projected according to income level and needed service level of each person. in addition, demand sufficiency of home nursing care is taken by estimating for supply level available. Result : home nursing care service is scarecely provided to people who belong to second area, that is, only $1.6{\sim}2.3%$ out of them are provided and also, supply system comes short of meeting demand of the other people(who belong to one, third area). Conclusion : therefore, for proper provision of home nursing care, different supply system and policy direction for establishment and expansion of home nursing care is to be developed.

• 수산경영론집
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• 제48권2호
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• pp.19-32
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• 2017

The purpose of this study is to identify problems and suggest improvements of estimating procedures and item of fisheries supply-demand statistics served as a basis for the fisheries supply-demand policies. Korea Rural Economic Institute(KREI) and Ministry of Oceans and Fisheries(MOF) respectively publish the fisheries supply-demand statistics. But the reliability of data is low as the statistics of these two organizations are limited and show discrepancy in the numbers. It is therefore difficult to use them as the basic data for policies. Also, an accurate data aggregation is difficult due to following problems in the items of statistics. 1) Problems in estimating route sales and non-route sales of production, 2) adequacy of fishery product yield rate compared to raw material in the fisheries import/export sector, 3) selection of target companies for understand stocks and survey scope of fish species, 4) applying'0'to non-edible product demand etc. In order to develop the fisheries industry as a future growth industry, it is necessary to establish the accurate fisheries supply-demand policy as the instability of fisheries supply and demand is increasing. To do this, statistical reliability has to be improved. The improvements proposed in this study should be implemented considering urgency. First of all, an exhaustive analysis of stock statistics and conversion rates of raw material yield in the fisheries import/export sector should be conducted. In the medium term and the long term, transferring production statistics to MOF and surveys on the use demand of non-food product and the level of reduced and discarded seafood products should be carried out in consecutive order.

• 대한산업공학회지
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• 제31권3호
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• pp.210-218
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• 2005

In the current global business environment, it is very important how to allocate products from the producer to buyers (or distributors). Sometimes some buyers can order more than pertinent demand due to inappropriate forecasting customers' orders. This is the big obstacle to the efficient allocation of products. If the producer can become aware of buyers' pertinent demand, it is possible to realize the high-level order fulfillment through the effective allocation of products. In this study, a new allocation policy is proposed considering buyers' demands. The backpropagation algorithm, one of algorithms in neural network theory, is used to find pertinent demands from the distributors' orders. In the experiment, an allocation policy considering buyers' demands outperforms previous allocation policies.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2006년도 추계학술대회
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• pp.142-146
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• 2006

This paper considers a SCM issue concerned with an integrated problem of inventory control and dynamic pricing strategies when demands are price and time dependent. The associated price markdowns are conducted for inventory control in a two-layer market consisting of retailer and outlet as in fashion apparel market. The objective function consists of revenue terms (sales revenue and salvage value) and purchasing cost term. Specifically, decisions on price markdowns and order quantity are made to maximize total profit in the supply chain so as to have zero inventory level at the end of the sales horizon. To solve the proposed problem, a gradient method is applied, which shows an optimal decision on both the initial inventory level and the discount pricing policy. Sensitivity analysis is conducted on the demand parameters and the final comments on the practical use of the proposed model are presented.

• 한국유기농업학회지
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• 제9권4호
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• pp.1-27
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• 2001

The number of organic farms are increasing in European countries during last 10 years. Most European governments are giving subsidies for organic farmers as well as converting organic farms from conventional farming method. The price level of most organic products are higher than price level of conventional products in general. However, there are certainly some market demand problems in organic products in some countries. Organic farms will be increased in 2005 and 2010 for 10∼20% of the total agricultural area in some European countries. Government subsidy payment is also increasing. Therefore, many farmers are going to change into organic farming method from conventional farming. However, there will be certainly some market demand problems in future because of national economic growth problems. At the same time, the quality of soil can be improved and status of health of urban consumers should be improved by consuming organic products.

• 산업경영시스템학회지
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• 제18권34호
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• pp.61-67
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• 1995

Through the model presented in this paper, we study on the depletion of stock taking place due to random loss of items as well as random demand, under the assumption that the distributions of demand are independent of those of loss, and both of them are identical, and that life time distribution of each item is negative exponential. The steady state probability distribution of the stock level assuming instantaneous delivery of order under (s, S) inventory policy. Also we have derived total expected cost expression with loss cost. The results of sensitive analysis show that the effect of loss rate is substantial on the total cost and optimal value of inventory level.