• 한국시스템다이내믹스연구
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• 제13권1호
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• pp.81-112
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• 2012

This study investigate the impact of supply chain contracts on supply chain performance. This study employed Price adjustment contract(PAC) and Quantity adjustment contract(QAC) as two main types of a vertical coordination mechanism. We simulate different types of coordination mechanisms with various degrees of demand uncertainties and several capacity tightness scenarios. This study shows that PAC and QAC significantly enhance the supply chain profits and fill rates suggesting that supply chain performance can be improved by implementing a proper coordination mechanism depends on the level of a capacity tightness and demand uncertainty.

• 보건행정학회지
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• 제33권4호
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• pp.457-478
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• 2023

Background: This study aims to contribute to the adjustment of the appropriate doctor manpower by analyzing the distribution, supply and demand, and estimation of the doctor manpower. Methods: This study utilized the medical personnel data of the Ministry of Health and Welfare, population trend data of the National Statistical Office, and health insurance benefit performance data of the National Health Insurance Service. Based on 2021, we compared the number of doctors in actual supply and the number of doctors in demand according to the amount of medical use by gender and age for 250 regions. Logistic regression analysis and scenario analysis were performed to estimate the future medical workforce by considering the demand for doctors according to the future demographic structure, the size of the quota in medical schools, and the retirement rate. Results: There were 186 regions in which the supply of doctors was below average, and the average ratio of the number of doctors in supply to demand in the region was 62.1%. Conclusion: In order to increase the number of active doctors nationwide to at least 80%, 7,756 people must be allocated. The number of doctors in demand is estimated to decrease after increasing to 1.492 times in 2059. The future projected number of doctors is expected to increase to 1.349 times in 2050 and then decrease taking into account the doctor quota and the retirement rate.

• 한국경영과학회지
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• 제30권1호
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• pp.17-26
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• 2005

There is the uncertainty of demands at each retailer in the supply chain. To satisfy customers' demand, retailer must have enough inventory. Nevertheless, stockout is occurred for some retailers. A lateral transshipment policy can be effectively used to deal with stockout. The new lateral transshipment policy, referred to service level adjustment (SLA), is suggested. The difference between SLA and previous policies is the integration of an emergency lateral 'transshipment with a preventive lateral transshipment to efficiently respond customers' demand in the proposed policy. Additionally, the service level to decide the quantity of products is considered. Simulation experiment is executed to treat stochastic factors in the two-echelon supply chain. The proposed policy can reduce total cost and is more effective to the change of demand, penalty cost, and ordering cost than the currently used policies.

• 농업과학연구
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• 제50권4호
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• pp.629-643
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• 2023

The purpose of this study was to examine the effectiveness and efficiency of a policy by comparing and analyzing the impact of the rice market isolation system and production adjustment system (strategic crops direct payment system that induces the cultivation of other crops instead of rice) on rice supply, rice price, and government's financial expenditure. To achieve this purpose, a rice supply and demand forecasting and policy simulation model was developed in this study using a partial equilibrium model limited to a single item (rice), a dynamic equation model system, and a structural equation system that reflects the casual relationship between variables with economic theory. The rice policy analysis model used a recursive model and not a simultaneous equation model. The policy is distinct from that of previous studies, in which changes in government's policy affected the price of rice during harvest and the lean season before the next harvest, and price changes affected the supply and demand of rice according to the modeling, that is, a more specific policy effect analysis. The analysis showed that the market isolation system increased government's financial expenditure compared to the production adjustment system, suggesting low policy financial efficiency, low policy effectiveness on target, and increased harvest price. In particular, the market isolation system temporarily increased the price during harvest season but decreased the price during the lean season due to an increase in ending stock caused by increased production and government stock. Therefore, a decrease in price during the lean season may decrease annual farm-gate prices, and the reverse seasonal amplitude is expected to intensify.

• KEPCO Journal on Electric Power and Energy
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• 제2권3호
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• pp.425-431
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• 2016

Supply Capability of the generator, if the maximum demand occurs, refers to the maximum power that can be stably supplied and it is possible to maintain stable power supply to be greater than actual load. However, unexpected power demand and reduction in supply Capability due to stop of unexpected generator in operation can temporarily make a big chaos in power system. In fact, due to a lack of power supply Capability in the country, enforced emergency load adjustment to the September 15, 2011, the circulation power outage has occurred in several cities. As the result, interrupted operation of the elevator and stopped hospital medical equipment led to a great deal of trouble to people's lives, causing a social problem. At that time, it was found that a failed frequency control because of smaller actual supply Capability than that of predicted. The difference was about 1,170 MW with Gas turbine power plant. By accurately calculating the generator supply capability, we can not only grasp the power reserve rate, but also correspond to the time of power supply instability.

• 한국측량학회지
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• 제40권4호
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• pp.261-273
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• 2022

본 연구는 시스템 다이내믹스 기법을 활용하여 성남시의 토지이용수요를 예측하고 가족구조 변화와 토지이용밀도 조정정책이 토지이용수요에 미치는 영향을 모의실험하는데 연구의 목적이 있다. 이를 위해 분석모형을 설계하고 시뮬레이션 결과를 통해 시간의 흐름에 따른 토지이용수요의 변화를 살펴보았다. 분석결과에 의하면, 2035년 기준으로 주거용지는 2.08km², 상업용지는 1.36km²의 추가 공급이 필요하고, 공업용지는 현재 공급면적으로 수요를 충족할 수 있는 것으로 나타났다. 한편, 기본 모형에서 변수값을 변경하여 세가지 정책실험을 실시하였다. 첫 번째 정책실험에서는 가구원수가 기본 모형에 비해 급격히 감소할 경우에는 주거용지가 최대 7.99km² 추가공급이 필요한 것으로 나타났다. 두 번째 정책실험에서는 아파트 용적율이 200%에서 300%로 상향하면 현재의 성남시 주거지역 공급면적으로 주거용지 수요 충족이 가능하였다. 세 번째 정책실험에서는 상업지역 평균층수를 4층에서 5층 상향하고 상업지역 건폐율을 80%에서 85%로 상향하더라도 상업용지의 수요가 성남시 상업지역 공급면적을 초과하는 것으로 나타났다. 본 연구는 시스템 다이내믹스를 활용하여 토지이용수요 예측의 새로운 분석모형을 제시하고, 성남시의 실제 도시계획 현황 및 통계치를 적용하여 모형을 실증하였다는데 연구의 의의가 있다. 향후 성남시 토지이용수요 예측 및 분석 모형의 정교화를 위한 후속연구가 이루어져야 할 것이다.

• 지역연구
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• 제14권1호
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• pp.109-126
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• 1998

We analysed the determinants of part-timer labor demand and supply in Kwangju. The findings of the paper are as follows; First, firms employ part-timer workers in the unskilled or skilled jobs not demanding much training cost. There are two reasons for firms to employ part-time workers: labor cost cut and flexible employment adjustment. Estimated wage differential is 40% not including fringe benefits differential. Second, we find lots of married women to want part-time jobs. The more probably married women choose part-time work, the younger and the less educated they are, and the less kids and the less other income they have.

• 한국인터넷방송통신학회논문지
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• 제15권4호
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• pp.223-230
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• 2015

본 논문은 대규모 불균형 수송 문제의 최적 해를 구하는 발견적 방법을 제안한다. 대규모 수송문제의 최적해를 찾는 방법은 일반적인 수송문제의 최적 해를 구하는 TSM을 적용하는데 어려움이 있어, 대부분은 상용화된 선형계획법 패키지를 활용한다. 그러나 상용화된 선형계획법 패키지가 최적 해를 얻었는지 검증할 방법이 없다. 본 논문은 공급지와 수요지가 $31{\times}15$인 대규모 불균형 수송문제에 대해 공급지를 기준으로 수요지가 몇 개인지를 파악하여 수요지 개수의 오름차순으로 수행하며, 각 수요지 개수에 대해서는 수요지가 1개인 경우 무조건 요구량을 배정하고, 수요지가 2개 이상인 경우, 공급지 기준의 최소 비용을 선택하고, 수요지 기준으로 비용 오름차순으로 요구량을 충족시키도록 배정하여 초기 해를 구하였다. 해 개선은 보다 큰 비용에 배정된 량을 보다 작은 비용으로 이동 가능한 조건을 만족하면 배정량을 조정하는 방법을 적용하였다. 제안된 방법을 $31{\times}15$비용행렬에 적용한 결과, 상용 선형계획법 패키지의 최적 해를 8.9% 개선하는 효과를 나타내었다.

• 한국가금학회지
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• 제47권1호
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• pp.39-48
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• 2020

The present study intended to analyze and detect any possible shortcomings in the current egg distribution system in Korea through a questionnaire. The institutional system and cases of operation thereof in advanced countries such as the USA, Japan, and Germany for the development of the egg distribution industry in Korea. The results revealed the following issues: absent pricing system, ineffective egg distribution, and difficulty in balancing supply and demand. Suggestions for addressing these issues and the subsequent improvement were based on cases found in the instated systems of advanced countries, and were given as follows: (i) The existing GP Center needs to be separated from the farms of laying hens, and the current institutional system and its operations need to be improved and should be approved by the government. Parallel to the institutional improvement, establishing a distribution system centered on the GP Center would be desirable. (ii) Egg pricing regulations are needed as a standard to determine the price of eggs. (iii) The reinforcing control standards and securing means for egg preservation are pertinent to each stage of egg distribution and should take into account environmental factors such as egg preservation temperature to guarantee high hygiene standards and egg safety.

• 대한간호학회지
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• 제51권6호
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• pp.703-719
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• 2021

Purpose: We aimed to identify collaborative disaster governance through the demand and supply analysis of resources recognized by nurses during the COVID-19 pandemic. Methods: We used a descriptive study design with an online survey technique for data collection. The survey questions were developed based on focus group interviews with nurses responding to COVID-19 and expert validity testing. A 42-question online survey focusing on disaster governance was sent to nurses working in COVID-19 designated hospitals, public health offices, and schools. A total of 630 nurses participated in the survey. Demand and supply analysis was used to identify the specific components of disaster governance during a pandemic situation and analyze priority areas in disaster governance, as reported by nurses. Results: Demand and supply analysis showed that supplies procurement, cooperation, education, and environment factors clustered in the high demand and supply quadrant while labor condition, advocacy, emotional support, and workload adjustment factors clustered in the high demand but low supply quadrant, indicating a strong need in those areas of disaster governance among nurses. The nurses practicing at the public health offices and schools showed major components of disaster governance plotted in the second quadrant, indicating weak collaborative disaster governance. Conclusion: These findings show that there is an unbalanced distribution among nurses, resulting in major challenges in collaborative disaster governance during COVID-19. In the future and current pandemic, collaborative disaster governance, through improved distribution, will be useful for helping nurses to access more required resources and achieve effective pandemic response.