• Title/Summary/Keyword: medium- and long-term

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Optimization of the Performance of Microbial Fuel Cells Containing Alkalophilic Bacillus sp.

  • CHOI, YOUNGJIN;JOOYOUNG SONG;SEUNHO JUNG;SUNGHYUN KIM
    • Journal of Microbiology and Biotechnology
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    • v.11 no.5
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    • pp.863-869
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    • 2001
  • A systematic study of microbial fuel cells comprised of alkalophilic Bacillus sp. B-31 has been carried out under various operating conditions. A significant amount of electricity was generated when redox mediators were used. Among the phenothiazine-type redox dyes tested, azure A was found to be the most effective both in maintaining a high cell voltage and for the long-term operation. The maximum efficiency was and for the long-term operation. The maximum efficiency was obtained at ca. $50^{\circ}C$ giving an open circuit voltage of 0.7V. A small change in temperature did not significantly affect the cell performance, but a rapid decrease in performance was observed below $20^{\circ}C$ and above $70^{\circ}C$. It was noticeable that fuel cell efficiency and discharge pattern depended strongly on the carbon source used in the initial culture medium. Regardless of the initial carbon sources, only glucose and trehalose were utilized as substrates. Galactose, however, was not substantially utilized except when galactose was used in the initial medium. Glucose, in particular, showed $87\%$ coulombic efficiency, which was the highest value ever reported, when Bacillus sp. was cultured in a maltose-containing medium. This study demonstrates that highly efficient microbial fuel cells can be constructed with alkalophilic microorganisms by fine-tuning the operating conditions and by carefully selecting carbon sources in the initial culture medium.

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Probabilistic Medium- and Long-Term Reservoir Inflow Forecasts (II) Use of GDAPS for Ensemble Reservoir Inflow Forecasts (확률론적 중장기 댐 유입량 예측 (II) 앙상블 댐 유입량 예측을 위한 GDAPS 활용)

  • Kim, Jin-Hoon;Bae, Deg-Hyo
    • Journal of Korea Water Resources Association
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    • v.39 no.3 s.164
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    • pp.275-288
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    • 2006
  • This study develops ESP (Ensemble Streamflow Prediction) system by using medium-term numerical weather prediction model which is GDAPS(T213) of KMA. The developed system forecasts medium- and long-range exceedance Probability for streamflow and RPSS evaluation scheme is used to analyze the accuracy of probability forecasts. It can be seen that the daily probability forecast results contain high uncertainties. A sensitivity analysis with respect to forecast time resolution shows that uncertainties decrease and accuracy generally improves as the forecast time step increase. Weekly ESP results by using the GDAPS output with a lead time of up to 28 days are more accurately predicted than traditional ESP results because conditional probabilities are stably distributed and uncertainties can be reduced. Therefore, it can be concluded that the developed system will be useful tool for medium- and long-term reservoir inflow forecasts in order to manage water resources.

Long-Term Evolution of Decaying MHD Turbulence in the Multiphase ISM

  • Kim, Chang-Goo;Basu, Shantanu
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.1
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    • pp.47.1-47.1
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    • 2013
  • Supersonic turbulence is believed to decay rapidly within a flow crossing time irrespective of the degree of magnetization. However, this consensus of decaying magnetohydrodynamic (MHD) turbulence relies on local isothermal simulations, which are unable to investigate the role of global magnetic fields and structures. Utilizing three-dimensional MHD simulations including interstellar cooling and heating, we investigate decaying MHD turbulence within cold neutral medium sheets embedded in warm neutral medium. Early evolution is consistent with previous studies characterized rapid decay of turbulence with the decaying time shorter than a flow crossing time and power-law temporal decay of turbulent kinetic energy with slope of -1. If initial magnetic fields are strong and perpendicular to the sheet, however long term evolutions of kinetic energy shows that a significant amount of turbulent energy still remains even after ten flow crossing times, and decaying rate is reduced as field strengths increase. We analyse power spectra of remaining turbulence to show that incompressible, in-plane motions dominate.

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A Study of Statistical Tools Application - Evaluation of Process Capability - (통계적기법(統計的技法) 활용(活用)에 관(關)한 연구(硏究) - 공정능력평가(工程能力評價)를 중심(中心)으로 -)

  • Seong, Won-Yong;Jung, Soo-Il
    • Journal of the Korea Safety Management & Science
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    • v.10 no.2
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    • pp.195-203
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    • 2008
  • The purpose of this study is to develop a guideline of process capability evaluation and to apply this guideline improving the quality of products, especially in the small and medium enterprises. In this study we deal in the concept of process capability evaluation, the calculation of process capability index, and the application of a case study. Man must compare the state of process with the standards in evaluating of the process capability. Control chart can be used as a yardstick for judgement for the long term period and the distribution shape of histogram for the short term period. Man should regard to the significant figure by the calculation of process capability index.

A Study on Development Strategies of the Korean Fisheries Outlook Project based on AHP (AHP 기법을 이용한 우리나라 수산업관측사업의 추진방향에 관한 연구)

  • Nam, Jong-Oh;Nho, Seung-Guk
    • The Journal of Fisheries Business Administration
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    • v.41 no.1
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    • pp.25-52
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    • 2010
  • The purpose of this paper is to suggest major strategies and necessary new projects for the medium- and long-term development of the Korean Fisheries Outlook Project. To suggest the Korean Fisheries Outlook Center with the above purpose, this paper employs Analytic Hierarchy Process analysis based on surveys obtained by special groups related with the KFOP. The survey is broadly composed of two goals; the medium- and long-term development directions and setting up of new furtherance projects. Each goal has upper and lower strategies respectively. The first goal, the medium- and long-term development directions, has four factors as upper strategies. The upper strategies are composed of accuracy, efficiency, timeliness, and political effectiveness of the fisheries outlook information. In addition, each upper strategy has three lower strategies respectively. For example, accuracy of the fisheries outlook information includes strength of data collection function, strength of satellite photography function, and strength of data analysis function. The second goal, setting up of new furtherance projects, has three factors as upper strategies. The upper strategies consist of accuracy promotion of outlook information using high-technique, field expansion of outlook species, and strength of analyzing function on oversea fisheries information. Each upper strategy has three lower strategies respectively. For instant, accuracy promotion of outlook information using high-technique has strength of information analysis function covered from production to consumption, strength of satellite information function, and structure of forecasting model on demand and supply by outlook species. The above upper and lower strategies were analytically drawn out through insightful interviews with special groups such as officials of the government, presidents of the producer and distributor groups, and researchers of the Korea Maritime Institute and other research institutes. As a result of AHP analysis, first, priorities of upper strategies with the medium- and long-term development directions are analyzed as accuracy, timeliness, political effectiveness, and efficiency in order. Also, priorities of all lower strategies reflecting priorities of upper strategies are examined as includes strength of data collection function on the fisheries outlook information, delivery of rapid information on outlook products for all people interested, strength of data analysis function on fisheries outlook information, strength of consumption outlook function on fish products, and strength of early warning system for domestic fish products in order. Second, priorities of upper strategies with the setting up of new furtherance projects are analyzed as accuracy promotion of outlook information using high-technique, field expansion of outlook species, and strength of analysis function on oversea fisheries information in order. In addition, priorities of all lower strategies reflecting priorities of upper strategies are examined as building up of forecasting model on demand and supply by outlook species, strength of information analysis function covering all steps from production to consumption, expansion of consumption outlook for consumers, strength of movement analysis function of oversea farming industry, and outlook expansion of farming species.

MEDIUM-TERM LIVER BIOASSAY FOR RAPID DETECTION OF CARCINOGENS

  • Hasegawa, Ryohei;Shirai, Tomoyuki;Ito, Nobuyuki
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1993.04a
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    • pp.91-91
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    • 1993
  • The vast number of compounds which have been introduced into our environment in recent years is far beyond our capacity to assess for carcinogenicity using expensive, life-time carcinogenicity studies in rodents. Several in vitro short term assays which are very rapid and inexpensive have therefore been applied as mass screening methods. However, increasing evidence has indicated that mutagenicity results do not always correlate with long-term carcinogenicity. Therefore, the existence of discrepancies dictates the necessity of suitable in vivo rapid assay systems which could bridge the gap between mutagenicity and conventional long-term testing.

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A Study on Selecting the Areas That Need to Be Improved in R&D and Production Management of SMEs (중소기업의 연구개발 및 생산운영관리 개선영역 도출에 관한 연구)

  • Chang, Youngsoon
    • Korean Management Science Review
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    • v.30 no.3
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    • pp.71-79
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    • 2013
  • This paper investigates and selects the areas that need to be improved in R&D and production management of small and medium size companies. The study on the capability of R&D and production management shows that the areas for evaluating of the R&D and production management levels are composed of 8 elements : R&D resource, R&D support and experience, long-term operations strategy, intermediate range planning, short-term planning, subcontractor management, logistics and inventory management, and quality management. The investigation of the gap between the importance of the areas and the capability of SMEs shows that the most important things are to consolidate supply chain, to improve product and process competitiveness using quality improvement, and to enhance production management through sophisticated short-term planning. The detailed analysis also shows that the areas that need to be improved depend on the size and sales of the company.

The Impact of M&A of Small and Medium-Sized Companies on Merger Disclosure Effect and Long-Term Operating Performance (중소기업의 M&A가 합병 공시효과와 장기 영업성과에 미치는 영향)

  • Kim, Byoung_jin;Jung, Jin-young
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.12 no.6
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    • pp.49-63
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    • 2017
  • The purpose of this study is to analyze the effects of the collective characteristics of SMEs on M&A activity on the disclosure effect of mergers and long-term business performance after mergers. From 2000 to 2012, we examine 717 cases of small and medium-sized enterprises (SMEs) using multiple regression analysis and difference analysis. The results of this study are as follows. First, it is confirmed that the effect on the merger announcement effect is the same as the previous study on the Korean capital market listed companies except for the effect of diversification, listing effect, and cross-border effect. In addition, we have found that firms with higher performance in the past have higher excess returns in the disclosure effect of mergers and acquisitions. Second, unlike the previous studies that non-related mergers have a positive effect on long-term operating performance, for the characteristics of SMEs with lower market competitiveness than that of average listed companies, SMEs merging with same industry group companies have a positive effect on long-term operating performance. This study provides a new perspective on the merger and acquisition of SMEs by examining the effects of M&A announcement and long-term performance.

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A Case Report of Treatment of Numbness Associated with Contrast Medium Injection using Modified Samul-tang (조영제 투여 후 초발한 저린감에 대한 사물탕가미(四物湯加味) 치료 증례보고)

  • Kwon, Jung-yeon;Bae, Ji-yong;Kong, Kyung-hwan;Go, Ho-yeon
    • The Journal of Internal Korean Medicine
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    • v.40 no.5
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    • pp.983-989
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    • 2019
  • Objective: Many types of delayed adverse reactions, such as long-term numbness, occur after injecting contrast medium, but few clinical studies have reported effective treatments for these reactions. We report that herbal medicine can have a positive clinical effect in patients who have experienced long-term numbness after contrast medium injection. Method: A patient who had felt numbness in her head and whole limbs presented at Semyung University Korean Medicine hospital. Her numbness had first started 2 days after injection of contrast medium, and she had felt it constantly for almost 2 years. After admission at the hospital, she took "modified Samul-tang" herbal medicine (120 cc three times per day) from 29 January 2019 to 2 February 2019. We measured her numbness using a numeric rating scale (NRS) on 29 January and 2 February and we compared both scores to determine the degree of favorable and clinical effects of herbal medicine. Result: The NRS score for numbness was 5 for her head and limbs on the first day (29 January), but after 4 days (2 February), the NRS score decreased to 0 for her head and both arms and hands, and it decreased from 5 to 2 for both her legs and feet. Conclusion: Korean herbal medicine can have positive clinical effects on treating adverse reactions due to injection of contrast medium.

A Study on Activation of Cooperative Employment through Long-term Field Placement: Based on Kumoh Institute of Technology including 3 Universities Case Study (장기현장실습을 통한 연계취업 활성화 방안 연구: 금오공과대학교 외 3개대학 사례를 중심으로)

  • Lee, Seok-moon;Jeong, Yeon-koo
    • Journal of Practical Engineering Education
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    • v.9 no.1
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    • pp.31-39
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    • 2017
  • Due to quantitative growth focused on short-term field placement and excessive competition between universities, the need for long-term field placement model is increasing and participation of government and universities is increasing for effective on-the-job training. In order to solve the problems of shortage of R&D manpower in small and medium sized companies, Kumoh Institute of Technology and three participating universities have been conducting industrial internship as R&D long-term field placement program from 2015. Students undertake long-term on-the-job training in the R & D department for six months to improve their R & D skills and strengthen their work capacity. In this paper, we propose effective ways of stimulating cooperative employment through long-term field placement in R&D departments from pre-preparation stage to ending stage through comparative analysis of cases of industrial internship in 2015 and 2016.