• Journal of the Korean Operations Research and Management Science Society
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• v.37 no.4
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• pp.37-50
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• 2012

The existing DEA models have been devoted to evaluate relative efficiency of DMUs based on multiple input and output factors of a same period. However, a certain kind of lead time can be required to produce outputs using inputs in an organization. R&D evaluation is a typical area with this kinds of time lag. Thus, the purpose of this paper is to develop a new DEA model to deal with time lag effect in performance evaluation. The proposed model is to find relative efficiency of each DMU for each period considering the time lag effect. A case example using a real data set is also given to show the usage or implication of the suggested model. The results are compared with the ones of the CCR model and the multi-periods input model.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2004.05a
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• pp.586-589
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• 2004

This paper attempts to propose the decision support model, which can be employed for 22 mail centers to improve their operational efficiency and competitive. This model deals with both DEA method and system dynamics model. DEA is a management tool aimed to determine relative efficiency of independent decision making unit. We measured the relative efficiency between mail centers using CCR model and tried to find the reason for inefficiency mail centers. Also, we introduced the system dynamics model to present the strategic policy for mail center to strengthen their efficiency.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.11a
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• pp.187-190
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• 2006

We proposed a new real estate price appra isal model that can appreciate the efficiencies of each criteria that would affect the price. The proposed Real Estate Price Appraisal Model is developed by the DEA-AR model which enhances the DEA-CCR model. We used the unit-cost per criteria method to set the assurance region of each weights of the DEA-AR model. In order to estimate the unit cost of major criteria effecting the price of real estate, we used the Goal Programming so that the price of real estate reaches the actual price being traded in. We expect that this approach could be helpful to make an objective real estate price appraisal.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.38 no.2
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• pp.108-119
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• 2015

This study intends to propose a non-oriented DEA based game cross-efficiency approach for supplier selection. With a discussion on the choice of DEA models and approaches that are most appropriate for supplier selection, we propose a game cross efficiency model based upon the non-oriented variable returns-to-scale RAM DEA by adapting the existing game cross efficiency model based upon the oriented constant returns-to-scale CCR DEA. We develop the RAM game cross efficiency model and a convergent iterative solution procedure to find the best game cross efficiency scores that constitute a Nash equilibrium. We illustrate the proposed model with two data sets of supplier selection, and demonstrate that significantly different results are obtained when compared with the existing approaches.

• Herbal Formula Science
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• v.21 no.1
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• pp.36-50
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• 2013

Objectives : To clarify the possible effect of Lycium chinese Mill (LC)., Morus alba L (MA)., and Lycium chinese Mill. +Morus alba L. (LC+MA), we have examined their influence on the development of pulmonary eosinophilic inflammation in the asthmatic murine model. Methods : Female Balb/c mice (5weeks) were immunized on two different days (21 days and 7 days before inhalational exposure) by intraperitonial injections of 0.2ml alum-precipitated Ag containing $100{\mu}g$ of OVA bound to 4 mg of aluminum hydroxide in PBS. Seven days after the second sensitization, mice were exposed to aerosolized ovalbumin for 30 minutes/day on 3 days/week for 8 weeks (at a flow rate of 250 L/min, 2.5% ovalbumin in normal saline) and, LC, MA, and LC+MA (500 mg/kg) were orally administered 3 times per a week for 8 weeks. Results : The suppressive effect of LC, MA, and LC+MA were demonstrated by the accumulation of eosinophills into airways, with the reduction of eosinophil, total lung leukocytes numbers. These were correlated with the marked reduction of IL-5, IL-13 and IL-4 levels in the BALF and serum. OVA-specific IgE levels were also decreased in serum and BAL from these mice. LC, MA, and LC+MA decreased eosinophil CCR3 expression and CD11b expression in lung cells. Conclusions : These results indicate that LC, MA, and LC+MA have high inhibitory effects on airway inflammation and hyper-responsiveness in the asthmatic murine model. The suppression of IL-5, IgE, eosinophil CCR3 expression and CD11b expression, and the increase of IFN-${\gamma}$ production in BALF seem to contribute to this effect. Hence, the results indicated that LC, MA, and LC+MA could act as a immuno-modulator which possesses anti-inflammatory and anti-asthmatic property by modulating the imbalance between Th1 and Th2 cytokines.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.10
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• pp.4354-4358
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• 2011

Many Korean construction companies have fallen on hard times because the construction business continues to stagnate. Therefore it is necessary to measure the management efficiency for efficient operation and strengthening competitiveness of them in order to survive a difficult situation. This paper proposes a combined ANP and DEA model to analyze the efficiency of the listed construction firms. In order to determine the input and output variables of DEA, the ANP model is applied to evaluate the importance of input and output variables. The benchmarking companies and efficiency value for the construction firms with inefficiency are also provided to improve the their efficiency. The 57 listed construction companies consisted of 36 listed on KOSPI and 21 listed on KOSDAQ are analyzed in this study. The analysis results show that 11 companies whose values of CCR are 1, and 14 firms whose values of BCC efficiency are 1. In additions, the 19 firms have the scalability efficiency. Finally, we test the correlation between efficiency and the stock price.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.41 no.3
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• pp.61-71
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• 2018

The purpose of this study is to analyze the efficiencies of project management offices in large information system construction projects using the data envelopment analysis. In addition, we tried to estimate the confidence interval of those efficiencies using bootstrap DEA to give a statistical meaning. The efficiency by the CCR model is analyzed as eight project management offices are fully efficient and 22 project management offices are inefficient. On the other hand, there are 15 project management offices are fully efficient, but 15 project management offices are inefficient in the BCC model. As the result of the scale efficiencies, of the inefficient project management offices, 13 project management offices are inefficient in scale. It is possible to eliminate the inefficiency in the CCR model by improving their project performances. And, the nine project management offices showed that the inefficiency was due to pure technical efficiency, and these companies should look for various improvements such as improvement of project execution system and project management process. In order that the inefficient project management offices be efficient, it is analyzed that more efforts must be made for on-budget and on-time as a result of examining the potential improvement potentials of inefficient project management offices.

• Journal of Digital Convergence
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• v.13 no.1
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• pp.341-351
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• 2015

This study was aimed to evaluate the effects of Cypress oil(CS) on anti-asthmatic activities in a mouse model of allergic asthma. Using an Ovalbumin-induced allergic asthma mouse model, 0.3% of CS was administered to experimental group using a nebulizer for 3 weeks on a basis of 3 times per week and 30min each time. The degree of airway hypersensitivity, the number of eosinophil in white blood cells, the number of immune cells and the change of cytokine in lung tissue were evaluated. The degree of airway hypersensitivity, the number of eosinophil, IL-5 and IL-13 levels in lung tissue, IgE in serum, the number of CCR3, CD3, CD4 cells were significantly decreased in experimental group treated with CS. These results suggested that CS may have a positive effects on Th2 cytokine and eosinophils which are major factors of asthma responses. Therefore CS might be of therapeutic value in treating asthma.

• Journal of Navigation and Port Research
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• v.48 no.4
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• pp.294-302
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• 2024

The risks in global grain markets have increased due to COVID-19, extreme weather, natural disasters, and the Russia-Ukraine conflict. Additionally, in Korea, the locations for grain manufacturing have shifted owing to various factors. Despite these environmental changes, grain handling ports in Korea are limited in their capacity to respond promptly, resulting in operational inefficiencies. This study clarified changes in grain throughput and analyzed the efficiency of grain handling ports using the Super-SBM model. It suggested that the ports in Pyeongtaek and Gunsan were the most efficient, based on CCR and BCC results in 2022. These findings could provide several insights related to port operating plans for port operators, managers, and developers.

• Proceedings of the KAIS Fall Conference
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• 2011.05b
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• pp.765-768
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• 2011

최근 건설경기의 난국 속에서 많은 건설기업들이 경영상의 어려움에 처해 있다. 본 연구에서는 코스피 코스닥 상장 건설기업들을 대상으로 ANP와 DEA 결합 모델을 이용하여 기업의 경영 효율성 분석을 실시한다. DEA 모형에 쓰이는 투입 및 산출 요소의 결정은 ANP 모형의 중요도 분석을 통하여 결정함으로써 기존의 방법보다 효율성 분석 결과의 신뢰도를 제고하였는데, 효율성 분석결과 비효율적 그룹에 대해서는 효율적 그룹으로의 이동을 위한 벤치마킹 대상과 개선을 위한 효율성 수치를 제공한다. 또한 연구의 결과로 나온 기업별 효율성과 주가와의 상관관계를 분석한다. 본 연구에서는 코스피 상장 건설기업 36곳과 코스닥에 상장된 건설기업 21곳인 총57개 기업을 대상으로 기업의 효율성을 평가하였는데, 효율성 분석결과 CCR 효율성이 1인 기업은 4개 기업, BCC 효율성이 1인 기업은 7개 기업, 규모의 효율성이 1인 기업은 4개 기업 이었으며 각각의 효율적 그룹군 기업과 주가와의 상관관계는 CCR, BCC 모형 모두에서 0.7 이상의 강한 양의 상관관계를 나타냈다.