• Title/Summary/Keyword: efficiency of scale

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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.

Unified Estimations for Parameter Changes in a Generalized Uniform Distribution

  • Kim, Jung-Dae;Lee, Jang-Choon
    • Journal of the Korean Data and Information Science Society
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    • v.13 no.2
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    • pp.295-305
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    • 2002
  • We shall propose several estimators for the shape and scale parameters in a generalized uniform distribution when both parameters are polynomial of a known exposure level, and obtain expectations and variances for their proposed estimators. And we shall compare numerically efficiencies for the several proposed estimators for the shape and scale parameters in a generalized uniform distribution in the small sample sizes.

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Ethanol Fermentation of Fusant between Heterologous Transformant of Saccharomyces cerevisiae and Candida tropicalis in Pilot Scale (Pilot Scale에서의 Fusant의 Ethanol 발효)

  • Seu, Jung-Hwn;Kim, Young-Ho;Lee, Soon-Mo;Bang, Byung-Ho
    • Microbiology and Biotechnology Letters
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    • v.17 no.1
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    • pp.14-18
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    • 1989
  • As the final experiment to assess the possibility of industrial application of FSC14-75, ethanol productivity from liquefied sweet potato starch was examined in a pilot scale of 300 liters. FSC14-75 produced 6.6%(v/v) of ethanol from 13.3% of liquefied sweet potato starch in 8 days, and the residual sugar was 3.15%. The corresponding efficiency was 70% of the theoretical maximum. Since we could isolate unicellular cell and flocculent cell from the fermentation broth, we designated them FSC14-75(S) and FSC14-75(F), respectively. We investigated ethanol productivity of FSC14-75(F) compared with that of FSC14-75(S) from liquefied potato starch in a mini·tar tormentor scale of 2.5 liters. FSC14-75(F) was found more favorable than the counterpart in terms of ethanol productivity, and produced 8.1%(v/v) of ethanol from 15% of liquefied potato starch with an efficiency of 75%. In a pilot scale fermentation with 15% of liquefied sweet potato starch, ethanol productivity of FSC14-75(F) reached maximum level of 7.7%(v/v) after 8 days, and the residual sugar was 1.9%. However, the ethanol productivity was not enhanced by a supplementary addition of Thermamyl to the fermentation broth after sterilization.

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Linear regression under log-concave and Gaussian scale mixture errors: comparative study

  • Kim, Sunyul;Seo, Byungtae
    • Communications for Statistical Applications and Methods
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    • v.25 no.6
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    • pp.633-645
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    • 2018
  • Gaussian error distributions are a common choice in traditional regression models for the maximum likelihood (ML) method. However, this distributional assumption is often suspicious especially when the error distribution is skewed or has heavy tails. In both cases, the ML method under normality could break down or lose efficiency. In this paper, we consider the log-concave and Gaussian scale mixture distributions for error distributions. For the log-concave errors, we propose to use a smoothed maximum likelihood estimator for stable and faster computation. Based on this, we perform comparative simulation studies to see the performance of coefficient estimates under normal, Gaussian scale mixture, and log-concave errors. In addition, we also consider real data analysis using Stack loss plant data and Korean labor and income panel data.

Measuring Efficiency and Productivity of the Korean Public Hospitals (공공병원의 효율성 및 생산성 분석)

  • You Taewoo;Yim Jongeun;Zi Hongmin
    • Journal of the Korean Operations Research and Management Science Society
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    • v.29 no.3
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    • pp.79-98
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    • 2004
  • Despite its contribution to the Korean medical service industry the question of how efficiently the Korean public hospitals have operated has been unresolved. This study gauges and analyzes the overall efficiency and the Malmquist productivity index in the industry over the period 1992 through 2001. In addition to cost efficiency. we also measure technical, allocative, pure technical and scale efficiencies. Furthermore. the Malmquist index is decomposed into efficiency and frontier changes. We identify several important factors which seem to have strong relationship with various inefficiency estimates. The results indicate that on average the public hospitals has wasted a significant amount of resources and costs over the period. Unlike many other industries, the low level of cost efficiency of the public hospital industry is mainly due to allocative inefficiency rather than technical inefficiency. The Maimquist productivity indices seem both due to the frontier change and efficiency change, but with more effect by the former. The results also indicate that the turnover of hospital beds has played an important role in determining efficiency and productivity of this important industry.

Estimating Minimum Efficient Scale of Korean Mobile Telecom Market: Relation between Cost per Minute and Traffic Volume (국내이동통신서비스 시장에서의 최소효율규모 추정: 분당원가와 통화량 간 관계분석을 중심으로)

  • Choi, Sae-Sol;Han, Sung-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38C no.10
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    • pp.867-873
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    • 2013
  • Competition policy for growth and activation of market should consider structural nature of relevant industry closely. In this viewpoint, whether domestic MNOs(mobile network operators) are competing while securing the effect of scale economies and maximum production efficiency is an important element when looking for competition policy means of domestic mobile communication market. With this, present study analyzed level of MES (Minimum Efficient Scale) and whether achieving them or not through investigating the relation between the cost per minute and call traffic of domestic MNOs. This analysis is differentiated from existing econometric studies entailing several assumptions by enhancing a reality reflection through directly deducing of cost curve using verified data(cost per minute and call traffic). As a result of analysis, the levels of minimum efficient scale were different from each other between domestic MNOs, and an incumbent MNO(SKT) accomplished minimum efficient scale while entrant MNOs(KT and LGU+) could not yet reach minimum efficient scale level. This result demonstrates a gap exists in production efficiency level among domestic MNOs and implies that the policy to alleviate the gap among operators is required when establishing competitive policy in the future.

Large-scale 3D fast Fourier transform computation on a GPU

  • Jaehong Lee;Duksu Kim
    • ETRI Journal
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    • v.45 no.6
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    • pp.1035-1045
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    • 2023
  • We propose a novel graphics processing unit (GPU) algorithm that can handle a large-scale 3D fast Fourier transform (i.e., 3D-FFT) problem whose data size is larger than the GPU's memory. A 1D FFT-based 3D-FFT computational approach is used to solve the limited device memory issue. Moreover, to reduce the communication overhead between the CPU and GPU, we propose a 3D data-transposition method that converts the target 1D vector into a contiguous memory layout and improves data transfer efficiency. The transposed data are communicated between the host and device memories efficiently through the pinned buffer and multiple streams. We apply our method to various large-scale benchmarks and compare its performance with the state-of-the-art multicore CPU FFT library (i.e., fastest Fourier transform in the West [FFTW]) and a prior GPU-based 3D-FFT algorithm. Our method achieves a higher performance (up to 2.89 times) than FFTW; it yields more performance gaps as the data size increases. The performance of the prior GPU algorithm decreases considerably in massive-scale problems, whereas our method's performance is stable.

The opening efficiency of the miniaturized large-scale net for anchovy boat seine to reduce the fleet size (선단 축소를 위한 기선권현망 축소형 대형 어구의 전개 성능)

  • AN, Young-Su;BACK, Young-Su;JIN, Song-Han;JANG, Choong-Sik;KANG, Myoung-Hee;CHA, Bong-Jin;CHO, Youn-Hyoung;KIM, Bo-Yeon;CHA, Ju-Hyeng
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.54 no.1
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    • pp.12-24
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    • 2018
  • This study was conducted in order to improve opening efficiency of the miniaturized large-scale net for anchovy boat seine gear to reduce the fleet size. Field experiments were performed to observe geometry of nets by catcher boats. When the distances between the two ships were 150, 300 and 450 m, and the speeds of towing nets were 0.6, 0.9, and 1.2 k't, respectively. The vertical opening and actual opening of each part of the miniaturized large-scale net was as follows: the front part of the wing net, 8.7-13.3 m, 51-78%; the middle part of the wing net, 28.1-34.2 m, 55-67%; the entrance of the inside wing net, 31.3-38.5 m, 60-73%; the square and bosom, 22.7-29.6 m, 47-62%; the entrance of the body net, 20.9-26.4 m, 42-52%; the entrance of the bag net, 17.2-21 m, 72-89%; the flapper, 13.2-15.3 m, 78-83%; and the end of the bag net, 13.2-15.7 m, 72-75%. By connecting the net pendants with the front part of the wing net, the opening of the front part of the wing net was significantly improved compared to the traditional gear, which ensured both the wing net and the inside wing net with a normal net height. This, in turn, increased the efficiency of herding. The height of the body and bag nets was also higher than that of the tradition gear. In particular, the body net attached to the gear significantly improved the pocket shape of the gear and reduced the number of fish that were caught and escaped from the bag net, which increased the rate of fishing. The tension of towing nets was measured approximately between 2,958 and 7,110 kg, which indicates that the fleet can tow nets with 350 ps, the standard engine horse power. The fishing operation time was shortened compared with of the existent net, and the large-scale buoy attachment operation was also possible to operate the ship without fish detecting boat.

A Production Efficiency Analysis of Cucumber Farms in South Korea (시설오이 재배농가의 생산효율성 분석)

  • Kim, Hae-min;Jang, Min-ki;Yi, Hyang-Mi
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.10
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    • pp.6823-6831
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    • 2015
  • The purpose of this study is to analyse cucumber farms managing efficiency and to draw some factors needed to maximize farms production efficiency. After reviewing and analysing some cucumber farms main management index in detail, we found that, compared to scale improvement, technical efficiency has more potential to increase cucumber farms income. Moreover There is a positive correlation between cucumber production and farms pure technical efficiency slightly, but because of the degree, we suggested to reduce input elements for enhancing pure technical efficiency under certain conditions.

Performance Evaluation and Characteristic Study of the Single Anaerobic Digestion from Piggery Slurry (돈분 슬러리를 이용한 단상 혐기소화공정의 특성연구 및 성능평가)

  • Park, Woo-Kyun;Jun, Hang-Bae;Park, Noh-Back;Kwon, Soon-Ik;Shin, Joung-Du;Hong, Seung-Gil
    • Korean Journal of Environmental Agriculture
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    • v.30 no.1
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    • pp.31-36
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    • 2011
  • BACKGROUND: Disposal of slurry animal manure produced by an anaerobic slurry-type barn method is not easy since the animal slurry contain high moisture content which makes solid-liquid separation a difficult process. However, recently, the interest about anaerobic digestion process as an environment-friendly waste disposal method has gained a wide interest because it can treat highly organic matter contained by the piggery slurry, decrease the odor after treatment, and enable the effective recovery of the methane gas which is a valuable energy resource. The objectives of this study were to identify the solubilization characteristics and to improve the anaerobic digestion efficiency of piggery slurry through full-scale anaerobic digestion experiments. METHODS AND RESULTS: In a full-scale continuous anaerobic digestion operation, the adaptability of single anaerobic digestion and its digestion efficiency were also evaluated in the farm field. The actual pH range and alkalinity concentration of piggery slurry used during the operation were comparatively higher than the concentrations of pH and alkalinity in the digestion tank which were stable at 7.5~8.0, 4,008 mg/L (as$CaCO_3$), respectively. The removal efficiency of organic matter (TCOD) by anaerobic digestion was 75~90% and methane gas production amount was at 0.33 L/L/day, a little higher than that of ordinary animal manure. CONCLUSION(s): Our findings showed higher recovery of highly purified methane and greater efficiency of anaerobic tank digestion since its methane gas content was at 65~70%.