• Title/Summary/Keyword: Research efficiency

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Binary and ternary gas mixtures of He-Ne-Xe for improvement of vacuum ultraviolet luminous efficiency in ac-PDPs.

  • Jung, Kyu-Bong;Lee, Jun-Ho;Park, Won-Bae;Jeon, Wook;Oh, Phil-Young;Cho, Guang-Sup;Uhm, Han-Sup;Choi, Eun-Ha
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.522-524
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    • 2004
  • The improvement of luminance and luminous efficiency is the one of the most important part in AC-PDPs. To achieve high luminance and luminous efficiency, high VUV emission efficiency is needed. We measured the emission spectra of vacuum ultraviolet(VUV) rays in surface discharge AC-PDP with binary and ternary gas mixtures of Ne-Xe and He-Ne-Xe. The influence of He-Ne-Xe gas-mixture ratio on excited $Xe^{\ast}$ resonant atoms and $Xe_2$$^{\ast}$ dimers has been investigated. It is found that luminous efficiency of ternary gas mixture, He-Ne-Xe, is shown to be much higher than that of binary gas mixture of Ne-Xe.

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Operating performance of squid jigging vessel using the LED and metal halide fishing lamp combination (LED와 메탈핼라이드 집어등을 겸용한 오징어채낚기 어선의 조업 성능)

  • An, Heui-Chun;Bae, Jae-Hyun;Bae, Bong-Seong;Park, Jong-Myung
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.49 no.4
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    • pp.395-403
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    • 2013
  • Fishing efficiency of the squid jigging vessel using the LED and metal halide fishing lamp combination was analyzed to reduce the cost for fishing operation utilizing the fishing light system for high degree of efficiency in the squid jigging fishery (one of the representative coastal and offshore fisheries in Korea). This study aims to improve the nature of existing LED lamps and to develop fan-shaped LED lights having 180W of power and ${\pm}45^{\circ}$ angle of light intensity distribution. The marine experiment for making a comparison of their fishing efficiency was tested by a 9.77 tons fishing vessel from Oct. through Dec. 2012. As a result, experimental fishing vessel showed slightly higher fishing efficiency than the average of metal halide lamp-equipped vessel and 20% energy savings. This means that the combination of LED and metal halide lamps would provide an efficient way to lower energy consumption while maintaining fishing efficiency.

Multi-criteria Decision Making Method for Developing Greenhouse Gas Technologies Strategically Considering Scale Efficiency: AHP/DEA CCR-I and BCC-I Integrated model Approach (규모의 경제성을 고려한 전략적 온실가스저감기술 개발을 위한 다기준의사결정기법: AHP/DEA CCR-I 및 BCC-I 혼합모형 적용)

  • Lee, Seong-Kon;Mogi, Gento;Kim, Jong-Wook
    • Transactions of the Korean hydrogen and new energy society
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    • v.19 no.6
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    • pp.552-560
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    • 2008
  • In 1997, Korean government established the National Energy and Resources Plan, which targeted from 1997 to 2005 with strategic energy technology development. At the end of 2005, Korean government built a New National Energy and Resources Plan preparing for upcoming 10 years from 2006 until 2015 based on energy technology trees comparing with the previous plan, which based on the energy R&D projects. In this research, we prioritize the relative preferences and efficiency by an AHP/DEA CCR-I and BCC-I integrated model approach considering scale efficiency for well focused R&D and efficiency of developing Greenhouse Gas technologies as an extended research from a view point of econometrics as an extended research.

The Development of the High-efficiency Rectifier on Marine Metallic Structures(II) (해양금속구조물의 전기방식을 위한 고효율 정류기 개발(II))

  • Ha, Tae-Hyun;Bae, Jeong-Hyo;Kim, Dae-Kyeong;Lee, Hyun-Goo;Choi, Sang-Bong;Jeong, Seong-Hwan
    • Proceedings of the KIEE Conference
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    • 2000.11d
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    • pp.727-728
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    • 2000
  • The Cathodic Protection system which is usually applied to marine metallic structures in domestic is Sacrificial Anode Method. In general. low efficiency rectifiers are using in the field of Cathodic Protection. These rectifiers are not only low efficiency but also manual type which is not able to control remotely. In this paper we describe the high efficiency rectifier used the high speed switching method for optimum corrosion control of marine metallic structures.

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The Development of the High-efficiency Rectifier on Marine Metallic Structures (해양금속구조물의 전기방식을 위한 고효율 정류기 개발)

  • Ha, Tae-Hyun;Kim, Dae-Kyeong;Bae, Jeong-Hyo;Lee, Hyun-Goo;Choi, Sang-Bong;Jeong, Seong-Hwan
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.3130-3132
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    • 2000
  • The Cathodic Protection system which is usually applied to marine metallic structures in domestic is Sacrificial Anode Method. In general, low efficiency rectifiers are using in the field of Cathodic Protection. These rectifiers are not only low efficiency but also manual type which is not able to control remotely. In this paper we describe the high efficiency rectifier used the high speed switching method for optimum corrosion control of marine metallic structures.

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The Evaluation of Relative Management Efficiency of Automobile Companies Using Non-parametric Approach (비모수 검정을 활용한 자동차 기업의 상대적 경영 효율성 평가)

  • Ha, Gui Ryong;Choi, Suk Bong
    • Knowledge Management Research
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    • v.15 no.2
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    • pp.147-164
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    • 2014
  • This paper investigated the efficiency of automobile firms by using several non-parametric approaches. First, using Data Envelopment Analysis (DEA), the paper has investigated the critical factors that determine the relative efficiency of management performance in automobile companies. Second, we examined how the firm size impact on the difference of this efficiency by using Kruskl-Wallis Test. Third, by using Mann-whitney test, we also investigated the difference of the efficiency accoss existence of technological innovation activity. Finally, the paper explored the relationship between technological innovation and management efficiency by using logistic regression model. The findings of this study provided practical information for inefficient automobile firms to find benchmarking firms and strategic position to improve their efficiency. The result also provided theoretical and methodological implications for those who explore factors affecting management efficiencies. Future research directions with the limitation of the study are discussed.

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Numerical Analysis of OLED Luminescence Efficiency by Hole Transport Layer Change (유기발광 소자의 수송층 두께 변화에 따른 수치적 해석)

  • Lee, Jung-Ho
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.17 no.12
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    • pp.1341-1346
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    • 2004
  • The OLED research is gone for two directions. One is material development research, and another one is structural improvement part. All two are thing to heighten luminescence efficiency of OLED. n other to improve luminescence efficiency of OLED Electron - hole pairs must consist much more in the device Their profiles are sensitive to mobility velocity of electrons and holes. In this paper, we demonstrate the difference of velocity between hole and electron by experiments, and compare with a data of simulation and experiment changing hole carrier transport layer thickness, so we get the optimal we improve luminescence efficiency. We suggest improving the efficiency of OLEDS would be to balance the injection of electrons and holes into light emission layer of the device. And, we improve understanding of the various luminescence efficiency through experiments and numerical analysis of luminescence efficiency in variable hole carrier transport layer's thickness.

Measuring production efficiency using Data Envelopment Analysis : The case of public Corporation Medical Centers (자료포락분석(DEA)을 이용한 효율성 측정 - 지방공사 의료원을 대상으로 -)

  • 박창제
    • Health Policy and Management
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    • v.6 no.2
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    • pp.91-114
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    • 1996
  • In this research, the Data Envelopment Analysis(DEA) was applied to measure production efficiency of Public Corporation Medical Centers(PCMCs) operating in Korea. The focus of this research is triple. First, identifing convenience and usefulness of DEA to measure the relative efficiency among PCMCs. Second, assessing magnitudes of the relative efficiency for each PCMC. Third, adding insights into some factors resulting inefficiency in PCMCs. Then, in this paper technical efficiency and scale efficiency measured by DEA[introduced by Charnes, Cooper, and Rhoides(1978) and Banker, Charnes, and Cooper(1984)] were analyzed and a new separate variable was introduced which makes it possible to determine whether operations were conducted in regions of increasing, constant or decresing returns to scale(in multiple input and output situations). And a multi-factor Tobit analysis was conducted to see which variables are associated with PCMC's efficiency.

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Evaluating the Efficiency of Mobile Content Companies Using Data Envelopment Analysis and Principal Component Analysis

  • Cho, Eun-Jin;Park, Myeong-Cheol
    • ETRI Journal
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    • v.33 no.3
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    • pp.443-453
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    • 2011
  • This paper evaluates the efficiency of mobile content firms through a hybrid approach combining data envelopment analysis (DEA) to analyze the relative efficiency and performance of firms and principal component analysis (PCA) to analyze data structures. We performed a DEA using the total amount of assets, operating costs, employees, and years in business as inputs, and revenue as output. We calculated fifteen combinations of DEA efficiency in the mobile content firms. We performed a PCA on the results of the fifteen DEA models, dividing the mobile content firms into those having either 'asset-oriented' or 'manpower and experience-oriented' efficiency. Discriminant analysis was used to validate the relationship between the efficiency models and mobile content types. This paper contributes toward the construction of a framework that combines the DEA and PCA approaches in mobile content firms for use in comprehensive measurements. Such a framework has the potential to present major factors of efficiency for sustainable management in mobile content firms and to aid in planning mobile content industry policies.

Statistical Difference of Production Efficiency in Medicinal Crop Farm (약용작물 재배농가의 생산효율성 통계적 차이에 대한 연구)

  • Choi, Don Woo;Kim, Dong Choon;Lee, Hang Ah;Lim, Cheong Ryong
    • Journal of Korean Society for Quality Management
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    • v.48 no.3
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    • pp.453-462
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    • 2020
  • Purpose::This study aims to analyze the management performance and production efficiency of medicinal crop farmers. Methods: We conducted an empirical survey of medicinal crop farmers and analyzed production efficiency using DEA method. Results: First, The crops that increased the number of farms during 2010 and 2018 were Angelica tenuissima and Salvia miltiorrhiza, which was attributed to higher income per hour than other crops. Second, As for the efficiency of Liriope platyphylla, the average was 0.376, and the coefficient of variation was the lowest, 0.566. Third, Salvia miltiorrhiza and Atractylodes japonica had the highest technical efficiency after Liriope platyphylla, but the variation coefficient was high and the efficiency was relatively high. Fourth, As a result of performing variance analysis to find out the difference of each crops on the value of medicinal crop efficiency, the technical efficiency, pure technical efficiency, and scale efficiency were all statistically significant. Conclusion: Based on the results above, following policy suggestions are offered. First, It is necessary to provide information on crops with high income compared to the input of labor, and to develop labor-saving cultivation technologies for each crop. Second, A stable labor supply system will be needed in rural areas. Third, Efforts should be made to close the technological gap between farmers through a lot of education and consulting for farmers who grow medicinal crops.