• Journal of Biosystems Engineering
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• v.35 no.2
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• pp.69-76
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• 2010

This study was conducted to develop an index of fuel consumption to rate agricultural tractors by their fuel efficiencies. The fuel consumption index consisted of two components: basic and operational indexes. The basic index is to consider an average amount of fuel consumed by engine when it transmits 20 and 100% of the rated power. The operational index is to consider the fuel consumed by tractor for typical field operations: plowing, rotavating, and the remains. The equations and procedures to obtain these indexes were proposed. The method and fuel consumption rate to classify tractors into 5 grades were also proposed. The best 15% of the tractor models were rated as the first grade, 20% as the second grade, 30% as the third grade, 20% as the fourth grade, and 15% as the fifth grade in order of fuel efficiency. Using the fuel consumption index, the classification was conducted on 143 tractor models tested at the National Institute of Agricultural Engineering from 2000 to 2007. The proposed 5-grade system of classification using the fuel consumption index could be used to rate the fuel efficiency of 20-100 kW tractor models produced over past 10 years in Korea.

• Journal of Navigation and Port Research
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• v.46 no.6
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• pp.547-553
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• 2022

This study analyzed the changes in the operational productivity of fourteen Korean container lines from 2019 to 2021 using MP I(Malmquist Productivity Index). The results indicated that the operational productivity of the shipping companies has increased by 38.4% annually, representing the TCI (Technical Change Index) increasing by 58.3% and the TECI (Technical Efficiency Change Index) decreasing by 12.6%. The increase in the operational productivity of the container shipping lines was mainly attributed to the high rise in ocean freight rates rather than an increase in fleet size or ship technical efficiency. However, the deep-sea shipping lines (i.e. HMM and SM lines) experienced increases in both the TCI and TECI, which was not the case for other shipping lines(i.e. Intra-Asian short-sea shipping lines). The intra-Asian short-sea shipping lines enhance their productivity due to the TCI but failed to appreciate the cost savings of the increased fleet effects due to the low SECI(Scale Efficiency Change Index) values.

• The Journal of the Korea Contents Association
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• v.17 no.1
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• pp.201-212
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• 2017

This study presented the new evaluation index which can evaluate the discrimination of DEA models. To evaluate the discrimination of DEA models, data were analyzed using importance index as suggested in previous study and the coefficient of variation as suggested in this study for the discrimination evaluation. This study selected the CCR-DEA, BCC-DEA, entropy, bootstrap, super efficiency, and cross efficiency DEA model for the discrimination evaluation and accomplished empirical analysis. In order to grasp the rank correlation of the models, this study implemented the rank correlation analysis between the efficiency of CCR model and BCC model and entropy, bootstrap, super efficiency, and efficiency of the cross efficiency model. The obtained results of this study are as follows. First, the discrimination rank of models using the importance index and the coefficient of variation was shown to be identical. Therefore, the coefficient of variation can be used the discrimination evaluation index of DEA model. Second, the discrimination of the super efficiency model was found to be the highest rank among 4 models according to the analysis of this present study. Third, the highest rank correlation with CCR model was the super efficiency model. In addition, the super efficiency model was found to be the highest rank correlation with BCC model.

• Journal of the Korean Statistical Society
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• v.30 no.3
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• pp.419-433
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• 2001

In this paper we introduce a method of improving efficiency of the moment estimator of Dekkers, Einmahl and de Haan(1989) for the extreme value index $\beta$. a new estimator of $\beta$ is proposed by adding the third moment ot the original moment estimator which is composed of the first two moments of the log-transformed sample data. We establish asymptotic normality of the new estimator and examine and adaptive procedure for the new estimator. The resulting adaptive estimator proves to be asymptotically better than the moment estimator particularly for $\beta$<0.

• Journal of Biosystems Engineering
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• v.39 no.2
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• pp.96-100
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• 2014

Purpose: The objective of this study was to develop a classification index and the grade levels for a five-grade energy efficiency classification of agricultural dryers in Korea. Methods: The classification index and the grade levels were determined by using the performance test data published by the FACT over the last eight years to reflect a state of the art technology for agricultural dryers in Korea. The five grades were designed to have the classified dryers distributed normally over the grades with 15% for the $1^{st}$ grade, 20% for the $2^{nd}$ grade, 30% for the $3^{rd}$ grade, 20% for the $4^{th}$ grade and 15% for the $5^{th}$ grade. Results: The classification index was defined as the total amount of fuel and electrical energy consumed per 1% of the wet basis moisture content evaporated from a unit mass of grain or agricultural crops during the drying process: 1 MT of paddy rice for grain dryers and 1 kg of red pepper for agricultural crop dryers as the standard mass. Conclusions: The grade levels for the five-grade energy efficiency classification of grain dryers, kerosene dryers, and electric dryers were proposed in terms of the classification index value.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6B
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• pp.723-729
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• 2008

Confidence intervals of growth curves are calculated to assess the uncertainty of index flood method as a regional frequency analysis. The asymptotic variance of quantile estimator for the generalized logistic distribution is introduced to evaluate confidence intervals. In addition, the variances of at-site frequency estimator and regional frequency estimator are used to evaluate an efficiency index. The efficiency indexes for 14 homogeneous regions based on 378 stations show that index flood method estimators are more efficient than at-site frequency estimators. It is shown that the number of sites in a region needs to be limited for regional gain.

• Journal of the Korean Operations Research and Management Science Society
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• v.37 no.4
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• pp.125-138
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• 2012

Health care that is considered to be one of the major factors for the quality of life is nowadays receiving a great deal of attention, and thus there is a growing need in Korea to identify the efficiency of national medical service and enhance the competitiveness. Although there exist studies on the medical service efficiency about general hospitals and local hospitals, they mostly deal with the efficiency problems from a domestic and regional perspective. In response, this paper analyzes the competitive efficiency of national medical service with respect to 16 OECD countries, by exploiting Data Envelopment Analysis (DEA) and Malmquist Productivity Index (MPI). Building on the DEA and MPI analysis results, this paper identifies the competitive position of Korean national medical service and suggests implications for the medical service improvement.

• Proceedings of the Korean Society for Quality Management Conference
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• 1998.11a
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• pp.419-428
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• 1998

In this paper, we analyzed two methodologies to evaluate the total quality management activities comparatively. One of them is the traditional scoring system (TSS) by analytic hierarchy process (AHP) and the other is the efficiency measuring system (EMS) by data envelop analysis (DEA), It is demonstrated that the index by TSS and the efficiency index by EMS are not correlated. Also, the efficiency index by EMS in terms of company characteristics such as the size of company and ISO certifications is different from the index by TSS. The result implies that to evaluate the quality activities by EMS is needed as a supplementory methodology.

• Journal of Korean Society for Quality Management
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• v.27 no.2
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• pp.47-56
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• 1999

In this paper, we analyzed two methodologies to evaluate the total quality management activities comparatively. One of them is the traditional scoring system (TSS) by analytic hierarchy process (AHP) and the other is the efficiency measuring system (EMS) by data envelop analysis (DEA). It is demonstrated that the index by TSS and the efficiency index by EMS are not correlated. Also, the efficiency index by EMS in terms of company characteristics such as the size of company and ISO certifications is different from the index by TSS. The result implies that to evaluate the quality activities by EMS is needed as a supplementary methodology.

• Journal of Korea Trade
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• v.25 no.1
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• pp.169-183
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• 2021

Purpose - This paper analyzes the effect of the agricultural export market for Korea's new southern countries in consideration of logistics efficiency. In order to expand Korean agricultural exports, the logistics performance index, national income, per capita income, consumer price index, distance and FTA are included. Through empirical analysis, the impact of logistics efficiency on Korean agricultural exports is derived and measures are proposed to expand exports in the future. Design/methodology - The analytical model of this study takes into account the import demand factors of the new southern countries for Korean agricultural exports. A research model was established based on prior research based on the gravity model, which is widely used in international trade effect analysis. In particular, logistics efficiency measures the effect on Korean agricultural exports using the logistics performance index and examines the effect by deriving factors for export expansion. Findings - The main findings of this study can be summarized as follows: The higher the logistics efficiency of the new southern countries in exporting Korean agricultural products, the more directly they have an effect on expanding exports. In addition, it was analyzed that the expansion of Korean agricultural exports has a positive effect on the other countries' national income, per capita income, consumer price index, population, and FTA. Based on these results, the importance of efficient logistics management in agricultural exports has been emphasized. Originality/value - There are not many studies on the export of agricultural products by logistics efficiency. However, prior studies that have adapted to manufacturing and other areas suggest that logistics efficiency has a direct effect on exports. This study suggests that Korean agricultural products are directly effective in exporting to new southern countries in terms of logistics efficiency. This can be an important time point in recognizing that logistics capabilities are important to ensure new books and the safety of agricultural products.