• 한국콘텐츠학회논문지
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• 제8권5호
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• pp.192-206
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• 2008

우리나라의 생명보험산업은 IMF 사태와 방카슈랑스의 도입 등 많은 변화를 겪어왔으며 앞으로 시행될 자본통합법의 시행도 추후에는 생명보험산업에 많은 영향을 미칠 것으로 보이며 생명보험회사의 경쟁력 강화를 위해서는 효율성의 분석이 필수적이다. 본 논문은 DEA 모형을 이용하여 우리나라에서 영업 중인 생명보험회사들의 효율성을 분석했다. 이를 위해 투입변수는 두 가지 범주로 나누어서 분석을 시도하였고 동태적 효율성을 분석하기 위해서 DEA/WINDOW 모형을 도입하였다. 이를 통하여 생명보험회사들의 CCR, BCC, 규모효율성을 알 수 있었고 7년간(1998년$\sim$2004년)의 효율성의 추세와 안정성을 파악할 수 있었다.

• Environmental Engineering Research
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• 제24권2호
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• pp.347-353
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• 2019

Although membrane distillation (MD) has great promise for desalination of saline water sources, it is crucial to improve its thermal efficiency to reduce the operating cost. Accordingly, this study intended to examine the thermal energy efficiency of MD modules in a pilot scale system. Two different modules of hollow fiber membranes were compared in direct contact MD mode. One of them was made of polypropylene with the effective membrane area of $2.6m^2$ and the other was made of polyvinylidene fluoride with the effective membrane area of $7.6m^2$. The influence of operation parameters, including the temperatures of feed and distillate, feed flow rate, and distillate flow rate on the flux, recovery, and performance ratio (PR), was investigated. Results showed that the two MD membranes showed different flux and PR values even under similar conditions. Moreover, both flow rate and temperature difference between feed and distillate significantly affect the PR values. These results suggest that the operating conditions for MD should be determined by considering the module properties.

• International Journal of Aeronautical and Space Sciences
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• 제9권2호
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• pp.79-86
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• 2008

High performance direct-iterative hybrid linear solver for large scale finite element problem is developed. Direct solution method is robust but difficult to parallelize, whereas iterative solution method is opposite for direct method. Therefore, combining two solution methods is desired to get both high performance parallel efficiency and numerical robustness for large scale structural analysis problems. Hybrid method mentioned in this paper is based on FETI-DP (Finite Element Tearing and Interconnecting-Dual Primal method) which has good parallel scalability and efficiency. It is suitable for fourth and second order finite element elliptic problems including structural analysis problems. We are using the hybrid concept of theses two solution method categories, combining the multifrontal solver into FETI-DP based iterative solver. Hybrid solver is implemented for our general structural analysis code, IPSAP.

• Journal of the Korean Data and Information Science Society
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• 제10권1호
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• pp.193-198
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• 1999

The estimation of parameters in regression models with multiplicative errors is usually based on the gamma or log-normal likelihoods. Under reciprocal misspecification, we compare the small sample efficiencies of two sets of estimators via a Monte Carlo study. We further consider the case where the errors are a random sample from a Weibull distribution. We compute the asymptotic relative efficiency of quasi-likelihood estimators on the original scale to least squares estimators on the log-transformed scale and perform a Monte Carlo study to compare the small sample performances of quasi-likelihood and least squares estimators.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2001년도 추계학술발표논문집
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• pp.87-94
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• 2001

Scale is agglomerate or thin film compounded of soluble salts in papermaking process. It causes many problems such as closing up pipelines, contaminating wire and felt, decreasing efficiency of additives and paper quality. In this study, physical factors related to forming scale in white water are determinated and optimum conditions are proposed. To control scale, ACP(Acrylacid Copolymer) was synthesized and compared with conventional chemicals such as EDTA, DTPA and STPP.

• 산업기술연구
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• 제18권
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• pp.1-6
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• 1998

This study was conducted to use disused vinyl as biofilm for biological sewage treatment. Efficiency verification was performed on laboratory and on-site plant. In laboratory study, total biochemical oxygen demand(TBOD) removal rate was ranged 94.8~97 % in each hydraulic retention tim(HRT), 12, 16, 20, 24 hr, respectively. At that time, filling rate was 50 %. And effluent TBOD concentration was low ranged 3.64~6.28 mg/L. In on-site plant, TBOD removal rate was ranged 88.2~96.8 % and effluent TBOD concentration was 4.8~17.7mg/L. This concentration was lower than disign effluent concentration, 30mg/L. Total kjeldhal nitrogen(TKN) removal efficiency was ranged 56.8~90.9%. This was resulted higher than Lab. scale treatment efficiency.

• 벤처창업연구
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• 제6권4호
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• pp.137-152
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• 2011

슘페터식 혁신은 이제 제조, 서비스산업을 넘어 농산업에서도 나타나고 있다. 농산업은 과거 가족농 중심의 단순생산체제를 탈피하여, 생산과 유통 전반으로 기업화되어 가는 경향이 나타나고 있는데, 이는 농산업부분에서의 낮은 생산성과 부가가치를 제고하기 위한 생산방식과 조직형태의 혁신이라고 볼 수 있다. 본 연구는 우리나라 농산업의 새로운 시도로 도입된 농업법인 그중에서도 농업생산법인의 생산성 수준을 파악하고 정책적 시사점을 도출하기 위하여 자료포락방법의 개선된 형태인 부트트래핑 자료포락방법을 활용하여 분석하였다. 본 연구의 주요 발견점은 다음과 같다. 분석대상 농업생산법인 중 효율성 값이 1인 효율적인 법인 수는 18.06%에 불과하며 효율성 값이 0.5 미만인 비효율적인 농업생산법인 수는 기술효율성에서는 30.92%, 순수기술효율성에서는 18.93%, 규모의 효율성에 있어서는 3.32%로 나타나 상당수의 농업생산법인이 비효율적인 상태에서 운영되고 있다. 이러한 분석결과는 농업생산법인이 농산업의 생산성 향상을 위한 방안으로 도입되기는 했지만 실질적 생산성 정도는 저조하다는 것을 의미하는 것으로, 농업생산법인의 생산성 제고를 위한 정책적, 전략적 차원의 개선책이 모색되어야 함을 보여 시사한다.

• 유통과학연구
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• 제16권5호
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• pp.91-101
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• 2018

Purpose - This study compares the management efficiency of retailers in China, Korea and other global countries. China's retail industry is experiencing a recession. In order to strengthen the competitiveness of retailers, it is necessary to manage the efficiency. Therefore, we analyzed the management efficiency of Chinese retailers as well as Korea and global retailers who are competing with Chinese retailers. Research design, data, and methodology - The DEA(Data Envelopment Analysis) carried out for evaluating the relative efficiency of multiple DMUs (decision making units) with homogeneity. Data were collected from the American Retail Trade Association (2017). In those distributors' data, 5 of China and 5 of Korea and 10 of other global countries' analyzed. CCR and BCC analysis were performed to determine the cause of the inefficiency of DMUs by measuring the technical efficiency, pure technology efficiency and scale efficiency. Result - Among the 20 retail distributors, Costco, Kroger (Global), Eland World, BGF(Korea) are operating efficiently. Chinese retailers are operating inefficiently. Retailers' CRS status means the growth rate of input is equal to the growth rate of output. In the case of DRS status, the ratio of output to input variable is much smaller. In order to improve inefficiency, reducing input variables can be a solution. For the firms in IRS status, the rate of increase in output is relative greater than the input. That means efficiency is good condition. The analysis result shows that most retailers are showing DRS status especially Chinese retailers. Scale efficiency is a major cause of inefficiency rather than pure technology efficiency. It is recommended for ineffective retailers to reduce inputs to become efficient retailers. Otherwise, retrain existing employees or introducing advanced technologies to increase the output. Conclusions - Most of Chinese retailers are operating inefficiently which caused by the excessive investment in the inputs. On the other hand, Other global retailers are analyzed to be efficient by DEA. In this study, benchmarking targets of some retailers' suggested to improve the management efficiency especially in inputs.

• Journal of East Asia Management
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• 제3권1호
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• pp.11-23
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• 2022

Under the circumstances of China's slower economic growth, the first document ofthe central committee of the CPC continue to focus on "three agricultures" problems, agriculture play a basic role on China's economic. Since 2007, the first document directly stresses the important role of agricultural and fisheries every year. Central Government Working Report of 2015 also stresses that under the new normal of economy, it is important to improve quality and efficiency of agriculture. Agricultural focus going forward will be on improving capacity of competitiveness, innovation and sustainable development.The fishery as an important part of agriculture plays a vital role in the protection of national food security, the prosperity of the rural economy and the optimization of national food structure. However, the situation faced on accelerating the speed of Chinese fisheries is still grim. As an important fishery breeding city in my country, Weihai has achieved remarkable results in the development of fisheries. Based on the input-output indicators of Weihai City from 2010 to 2020, this article uses the DEA model method to conduct a comprehensive analysis of the factors affecting the fishery production efficiency in Weihai City. This paper calculates the two stages of comprehensive efficiency, pure technical efficiency and scale efficiency, and comprehensive compares the two stages. The research results show that: From 2010 to 2020, the average comprehensive technical efficiency of Weihai fishery was 0.928, the average scale efficiency was 0.963, and the average pure technical efficiency was 0.963. The comprehensive technical efficiency of Weihai fishery production showed an upward and downward trend, the pure technical efficiency showed a downward and then upward trend, and the pure technical efficiency showed a fluctuating trend.

• 가정∙방문간호학회지
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• 제27권1호
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• pp.16-28
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• 2020

Purpose: The aim of this study was to evaluate the efficiency of long-term care visiting nursing centers in communities using data envelopment analysis (DEA). Methods: Data were collected using a self-reported questionnaire. The average number of staff per 6 months and total space of center were used as input variables. The average number of clients per 6 months and the average profits per 6 months were used as output variables. EMS Window version 3.1 was used to measure the efficiency scores. Descriptive statistics and tobit regression were applied to analyze the general characteristics of the variables and the factors affecting efficiency scores. Results: The average efficiency of 30 long-term care visiting nursing centers in communities was approximately 66.9% on technical efficiency analysis, and 79.1% on scale efficiency analysis. Eight nursing centers on technical efficiency analysis and 12 centers on scale efficiency analysis had 100.0% efficiency. Conclusion: Our findings reveal that long-term care visiting nursing centers in communities have low operational efficiency. Therefore, it is essential to institute policies and regulations to improve the efficiency of visiting nursing centers and to strengthen the business competencies of center officers.