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Efficiency of Analysis Agricultural R&D Program by Data Envelopment Analysis (DEA를 이용한 농림 R&D 사업의 효율성 분석)

  • Jun-Hyun Kim;Bong-Soo Lee;Jae-Kyung Kim
    • Korea Trade Review
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    • v.45 no.1
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    • pp.47-64
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    • 2020
  • For the past few years, the Korean government has been consistently expanding its national research & development budget to accelerate economic growth through technology innovation and the enhancement of international competitiveness in global markets. The objective of this paper is to define the concept and analyze the current status of national R&D programs by measuring R&D efficiencies. We determine R&D efficiency by reflecting inputs and outcomes of the five main agricultural R&D programs between 2010 to 2015, and by categorizing and regrouping figures that may affect R&D performance. Among 1,128 targeted projects, 832 projects with patents and thesis were selected for analysis in terms of measuring technology efficiency, pure technology efficiency, and efficiency of scale. Also, the Kruskal-Wallis test was also utilized as well. As a result of empirical analysis, figures that affected the efficiency level of national R&D programs included differences in research resources, research management levels and skills, and research field. This study can be utilized as a reference for re-establishing national agricultural R&D policies, such as enhancement of national technology competitiveness in the global market environment, improving and adapting to new agricultural conditions, market expansion, national agricultural R&D efficiency, aging rural population, agricultural management cost increase, and climate change mitigation.

Optimization Study on the Performance Analysis of Organic Rankine Cycle for Characteristics of Low Temperature Heat Sources (저온열원의 특성에 따른 ORC 성능해석 최적화 연구)

  • Eom, Hong-Sun;Yoon, Cheon-Seog;Kim, Young-Min;Shin, Dong-Gil;Kim, Chang-Gi
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.24 no.1
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    • pp.51-60
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    • 2012
  • Optimization procedures of performance analysis for ORC(Organic Rankine Cycle) system are established to the characteristics of low temperature heat sources such as open-type and closed-type. Effective heat recovery and heat extraction related to maximum power of the cycle as well as heat quality and thermal efficiency must be considered in the case of the open-type low temperature heat source. On the other hand, in the case of the closed-type low temperature heat source, only thermal efficiency is important due to constant heat input. In this study, thermal efficiency and exergy efficiency representing a level of close to Carnot cycle are studied, as useful index for the optimization of the ORC system. To validate the results of cycle analysis, those are compared with appropriate experimental data of ORC system as a thermal efficiency point of view.

Consumer Information Competency of Contemporary Consumers: Effects on Information Search Efficiency and Effectiveness for Purchase of Electronic Goods (현대 소비자의 소비자정보역량: 전자제품 구매 시 정보탐색 효율성 및 효과성에 미치는 영향)

  • Hwang, Hye Sun;Kim, Kee-Ok
    • Journal of the Korean Home Economics Association
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    • v.50 no.6
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    • pp.99-117
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    • 2012
  • This study aimed to measure consumer information competency, which indicates consumers' general ability to search and utilize information. The model of this study was constructed in order to identify how consumer information competency influences the efficiency and the effectiveness of external information search. The model was verified with related prior knowledge as a moderator variable in order to understand holistic consumer information search activity. The result of the study is as follows. First, the concept of consumer information competency was constructed with four sub-abilities: define, search, extract, and synthesis & use. The ability of define was the highest, as opposed to the ability of extract, which was the lowest. Second, consumer information competency was lower for women as well as for low family income. The sub-abilities of search and synthesis & use were lower for aging consumers. Third, consumer information competency has positive effects on information search efficiency and effectiveness. Moreover, the efficiency influences the effectiveness positively. Fourth, prior knowledge moderates the effect of consumer information competency to the efficiency. Only for consumers with high knowledge the efficiency has the effect of mediating between consumer information competency and the effectiveness.

Efficiency Effects of Mergers in the Korean Pharmaceutical Industry (국내 제약산업의 합병효과 분석)

  • Lee, Cheolhaeng;Cho, Keuntae
    • Journal of the Korean Operations Research and Management Science Society
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    • v.42 no.3
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    • pp.35-49
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    • 2017
  • The main objective of this paper is to empirically analyze the efficiency effects of mergers on Korean pharmaceutical firms and suggests managerial or policy implications for managers or policy makers. This study selects non-merging control firms close to the size of merging firms, as well as a set of merging firms, and measures the effects of mergers on efficiency three years before and after the merger using the non-parametric data envelopment analysis (DEA) method. To compare the differences of efficiency means among several groups, Wilcoxon rank sum test or Wilcoxon signed rank test is used. It showed that the long-term effects after the merger appeared partially. Furthermore, it was observed that there was no difference statistically in the efficiency between merging and non-merging firms. Also, there was no difference statistically in the efficiency between the pre- and post-merger periods. In conclusion, there was not any observed synergy effect through group (or affiliated) mergers between affiliates or related mergers for Korean pharmaceutical firms.

Improvement in LED structure for enhanced light-emission

  • Park, Seong-Ju
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2003.11a
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    • pp.21-21
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    • 2003
  • To increase the light-emission efficiency of LED, we increased the internal and external quantum efficiency by suppressing the defect formation in the quantum well and by increasing the light extraction efficiency in LED, respectively. First, the internal quantum efficiency was improved by investigating the effect of a low temperature (LT) grown p-GaN layer on the In$\sub$0.25/GaN/GaN MQW in green LED. The properties of p-GaN was optimized at a low growth temperature of 900oC. A green LED using the optimized LT p-type GaN clearly showed the elimination of blue-shift which is originated by the MQW damage due to the high temperature growth process. This result was attributed to the suppression of indium inter-diffusion in MQW layer as evidenced by XRD and HR-TEM analysis. Secondly, we improved the light-extraction efficiency of LED. In spite of high internal quantum efficiency of GaN-based LED, the external quantum efficiency is still low due to the total internal reflection of the light at the semiconductor-air interface. To improve the probability of escaping the photons outside from the LED structure, we fabricated nano-sized cavities on a p-GaN surface utilizing Pt self-assembled metal clusters as an etch mask. Electroluminescence measurement showed that the relative optical output power was increased up to 80% compared to that of LED without nano-sized cavities. I-V measurement also showed that the electrical performance was improved. The enhanced LED performance was attributed to the enhancement of light escaping probability and the decrease of resistance due to the increase in contact area.

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Analysis and Optimization of Wireless Power Transfer Efficiency Considering the Tilt Angle of a Coil

  • Huang, Wei;Ku, Hyunchul
    • Journal of electromagnetic engineering and science
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    • v.18 no.1
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    • pp.13-19
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    • 2018
  • Wireless power transfer (WPT) based on magnetic resonant coupling is a promising technology in many industrial applications. Efficiency of the WPT system usually depends on the tilt angle of the transmitter or the receiver coil. This work analyzes the effect of the tilt angle on the efficiency of the WPT system with horizontal misalignment. The mutual inductance between two coils located at arbitrary positions with tilt angles is calculated using a numerical analysis based on the Neumann formula. The efficiency of the WPT system with a tilted coil is extracted using an equivalent circuit model with extracted mutual inductance. By analyzing the results, we propose an optimal tilt angle to maximize the efficiency of the WPT system. The best angle to maximize the efficiency depends on the radii of the two coils and their relative position. The calculated efficiencies versus the tilt angle for various WPT cases, which change the radius of RX ($r_2=0.075m$, 0.1 m, 0.15 m) and the horizontal distance (y=0 m, 0.05 m, 0.1 m), are compared with the experimental results. The analytically extracted efficiencies and the extracted optimal tilt angles agree well with those of the experimental results.

Measuring Technical and Scale Efficiencies of Korean Seed Companies -On the Outset of Establishing the Center for Private Seed Companies- (국내 육종업체의 기술 및 규모효율성 분석 -민간육종연구단지 조성을 계기로-)

  • Gim, Uhn-Soon;Choi, Se-Hyun;Cho, Jae-Hwan;Jung, Yong-Gwan;Lah, Jung-Hyun
    • Korean Journal of Organic Agriculture
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    • v.22 no.1
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    • pp.1-23
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    • 2014
  • The purpose of this paper was to measure technical efficiencies and scale efficiencies of Korean seed industry by DEA method, and to identify the factors affecting the efficiencies by Tobit regression model. Survey data of 50 seed companies nationwide were applied for the analysis. The average score of overall technical efficiency for the surveyed companies in 2012 was 0.44, which is decomposed into pure technical efficiency 0.68 and scale efficiency 0.63. A majority of the seed companies exhibited at least one form of inefficiency except a few companies in optimal scale. It was also shown the most companies were operating in the stage of increasing returns to scale, which implies Korean seed companies are mainly in smaller scale than optimal. Additional results suggest that the Center for Private Seed Companies, which will be established at Gimje in 2015, plays an important role to make domestic seed companies improve their scale efficiency as well as pure technical efficiency by way of enlarging their size and co-using the high technology in the Center.

AN EXPERIMENTAL STUDY ON THE EFFICIENCY OF A LOCAL VENTILATION SYSTEM AND THE PROTECTING FACE MASKS IN DENTAL LABORATORIES

  • Kim, Uoong-Chul
    • Journal of Technologic Dentistry
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    • v.11 no.1
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    • pp.95-102
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    • 1989
  • This study was performed to study the efficiency of a local ventilation system, installed in dental laboratories, and of two types of protecting face masks. The dust originating from the workpiece as well as from the wheels and stones was collected on air filters in the cutting cycle during coarse and fine grinding, and in the subsequent polishing procedures of each specific dental material. The efficiency of the ventilation system was measured on the basis of weight reduction of dust in the breathing air at a distance about 20-40 cm from workpiece. The results were as follows: 1. Use of the local ventilation system reduced the amounts of respirable dust to an average level of 21.4%, although the efficiency of the local ventilation system varied depending upon materials used. 2. Mounting a nozzle on the tube improved the efficiency of the ventilation system considerably. The efficiency of the local ventilation system also increased as the workpiece was closing to the tube inlet. 3. With or without the local ventilation system, the distance between the position of the workpiece and sampler greatly affected the dust level. 4. The face masks covering the sampler improved the efficiency of the ventilation system considerably.

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Study on the Device for Pump Efficiency Measurement (펌프의 효율측정 장비에 관한 연구)

  • Bae, Cherl-O
    • Journal of Korea Ship Safrty Technology Authority
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    • s.33
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    • pp.53-62
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    • 2012
  • Pumps are used widely in feed water, cooling & heating system and process line of industrial and construction fields. They consume nearly 20% of the each nation's total electrical energy. But The management of pump energy wasn't controlled well. Their loss of energy is huge if they have been operated at low efficiency. The first buying cost of pump is small compare to the power consumption of pump, so we can recommend the suitable replace time and best operating condition of parts and pump to measure the pump efficiency. Pump efficiency is usually measured according to the two methods which they are called thermodynamic method and traditional technique. And we measured the pump efficiency using two methods using potable pump efficiency measurement device and compared the results with the real performance curve offered from pump maker.

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Data Envelopment Analysis of Managerial Efficiency of China, Korea and Other Global Retail Distributors (자료포락분석을 이용한 중국·한국·글로벌 소매유통업체 경영효율성 분석)

  • Wang, Peng;Kim, Moon-Hong
    • Journal of Distribution Science
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    • v.16 no.5
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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.