• Title/Summary/Keyword: Selection process

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Numerical Simulations of Water Quality in ManKyong River (QUAL-II E 모델에 의(依)한 만경강(萬頃江)의 수질예측(水質豫測))

  • Shim, Jae-Hwan;Choi, Moon-Sul
    • Korean Journal of Environmental Agriculture
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    • v.10 no.1
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    • pp.67-75
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    • 1991
  • The QUAL-II E Model was applied to predict the water quality of the Mankyong drainage System, and lead to following conclusion. 1. The difference between computed and measured BOD at the M-3 (Bakgugeong) station was within 10%, indicating that the application of the QUAL-IIE Model for the prediction of water quality was satisfactory thus far. 2. The application of the model states that the discharge of concentrated pollutants at the M-1 station on the Jeonju stream, located 41Km upstream from the estuary, causes the worst problems. The sluice which extends residence time and enlarges watery surface improves water quality by a Self-purification process at the M-3 station, 28km upstream from the estuary. 3. The accuracy of the model diminished when this model was applied on the estuary downstream of the sluice. Hence, the application of the model on the estuary needs to be used with caution. 4. Among the conputed water quality parameters, BOD is the worst problem. At the M-3 station, BOD is computed to be 26.6 mg/1 in 1996, 30.7 mg/1 in 2,001, 33.0 mg/l in 2006, and 37.5 mg/1 in 2011. When preventive measures against water pollution are not properly exercised, severe problems in irrigation and water resources are expected. This study will be of used in the selection of irrigation water intake points, the criteria of effluent treatment, the management of water resources, and the establishment of water quality managemont policy.

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A Model of Four Seasons Mixed Heat Demand Prediction Neural Network for Improving Forecast Rate (예측율 제고를 위한 사계절 혼합형 열수요 예측 신경망 모델)

  • Choi, Seungho;Lee, Jaebok;Kim, Wonho;Hong, Junhee
    • Journal of Energy Engineering
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    • v.28 no.4
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    • pp.82-93
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    • 2019
  • In this study, a new model is proposed to improve the problem of the decline of predict rate of heat demand on a particular date, such as a public holiday for the conventional heat demand forecasting system. The proposed model was the Four Season Mixed Heat Demand Prediction Neural Network Model, which showed an increase in the forecast rate of heat demand, especially for each type of forecast date (weekday/weekend/holiday). The proposed model was selected through the following process. A model with an even error for each type of forecast date in a particular season is selected to form the entire forecast model. To avoid shortening learning time and excessive learning, after each of the four different models that were structurally simplified were learning and a model that showed optimal prediction error was selected through various combinations. The output of the model is the hourly 24-hour heat demand at the forecast date and the total is the daily total heat demand. These forecasts enable efficient heat supply planning and allow the selection and utilization of output values according to their purpose. For daily heat demand forecasts for the proposed model, the overall MAPE improved from 5.3~6.1% for individual models to 5.2% and the forecast for holiday heat demand greatly improved from 4.9~7.9% to 2.9%. The data in this study utilized 34 months of heat demand data from a specific apartment complex provided by the Korea District Heating Corp. (January 2015 to October 2017).

2008 Dietary Goals and Dietary Guidelines for Korean Adults (2008 한국 성인을 위한 식생활목표와 식생활지침)

  • Paik, Hee-Young;Kim, Cho-Il;Moon, Hyun-Kyung;Yoon, Jin-Sook;Joung, Hyo-Jee;Shim, Jae-Eun;Jung, Hyun-Ju
    • Journal of Nutrition and Health
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    • v.41 no.8
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    • pp.887-899
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    • 2008
  • Recently the Ministry of Health and Welfare, Republic of Korea, announced the “Dietary Guidelines for Korean Adults (DGKA)”, which includes ten Dietary Goals, six Dietary Guidelines, and twenty-three Action Guidelines. DGKA are developed as the revision of the 2003 Dietary Guidelines for Koreans, targeting adult population. Dietary Guidelines are developed for general purpose as well as for different age groups. They are revised periodically to accommodate changes in diet and health problems of the population. The process of developing new DGKA can be summarized as 1) selection of focus areas, 2) analysis and review of available data for each area selected, and 3) derivation of guidelines based on the analyzed data, and 4) finalizing the guidelines after open discussions among the experts and general public. Five focus areas were selected by examining the Nutrition Goals of the Health Plan 2010 of Korea, soliciting proposals from the experts in the related fields, and reviewing existing and international guidelines. Five areas selected were 1) adequate intake of nutrients and foods, 2) balance of energy intake and physical activities, 3) alcohol intake, 4) food security and nutrition service, and 5) food safety. Adequacy of nutrient and food intakes of the Korean adult population was assessed using 2005 Korea National Health and Nutrition Examination Survey (KNHANES) data. Newly developed Dietary Reference Intakes for Koreans were used as reference values to assess the prevalence of inadequacies and excesses in nutrient intakes. Energy balance was examined with energy intake of 2005 KNHANES survey and results of physical activity questionnaire in the survey. Alcohol intake was also examined using 2005 KNHANES results of dietary intakes as well as the results of questionnaire survey on alcohol intakes. Food security, nutrition services, and food safety were analyzed using various government data and published results on the issues. Ten Dietary Goals and six Dietary Guidelines were developed after data analysis and were subjected to reviews of experts and general public. The final DGKA are: 1) Eat a variety of foods from each food group, 2) Increase physical activity and maintain healthy weight, 3) Eat proper amount of clean foods, 4) Avoid salty foods and try to eat foods with bland taste, 5) Avoid foods with high fat contents and deep-fried foods, and 6) When you drink alcohol, limit the amount. Twenty-three action guidelines are developed in order to achieve these guidelines in actual diet and life among the population. The government is disseminating the guidelines with “337” slogan and emblem. “337” indicates everyone should practice “3” guidelines of promoting good eating practice, “3” guidelines to limit or decrease in your diet, and you should practice them for “7” days a week. The guidelines will be useful in promoting healthy food habits and good nutritional status which will result in decrease nutrition related health problems in Korea.

Optimization of solid phase extraction and simultaneous determination of trace anions in concentrated hydrofluoric acid by ion chromatography (불산 중 극미량 음이온 분석을 위한 고상 추출법 및 이온크로마토그래프를 이용한 동시분석법 확립)

  • Yoon, Suk-Hwan;Jo, Dong-ho;Kim, Hyun-Ji;Shin, Ho-Sang
    • Analytical Science and Technology
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    • v.29 no.5
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    • pp.219-224
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    • 2016
  • 불산 중 극미량 음이온의 고상추출과 이온크로마토그래프를 이용한 고감도 분석법이 개발되었다. 불산 중 불소이온이 고상에 의해 제거하였고 이어서 음이온 (F, CH3COO, Cl, Br, NO3, PO43−, SO42−)들이 이온크로마토그래프를 이용하여 연속적으로 분리하였다. 고상 추출법에 영향을 주는 각 인자들 (흡착제의 선택, 시료의 부피 및 pH, 용출 용액과 용출용액의 부피)을 결정하였으며 그 결과 흡착제로서 Oasis WAX 컬럼이 가장 우수하였고 1.0 mL의 시료부피, 용출용액으로 50 mM 초산암모늄염 5 mL가 분리능에서 가장 우수하였다. 개발한 방법에 의한 음이온 (Cl, Br, NO3, PO43−, SO42−)들의 방법검출한계는 25 % 불산용액 (w/w) 중에 0.04~0.30 µg/L의 범위를 보였고 정밀도는 20.0와 40.0 µg/L의 농도에서 5 % 이내를 보였다. 한 제조회사에 의한 25 % 불산 중 음이온의 4.2에서 47.5 µg/L의 범위로 모두 검출되었다. 이 방법은 시험절차가 간단하고, 재현성 및 감도가 좋아서 반도체회사에서 불산 중 음이온 불순물을 정도 관리하는데 매우 유용한 방법이 될 것으로 판단된다.

Optimum Conditions of Enzymatic Reactions for Production of Isomaltooligosaccharides from Rice Flour (쌀가루로부터 이소말토올리고당 제조를 위한 효소반응 최적 조건)

  • Park, Ji-in;Shin, Jiyoung;Yang, Ji-young
    • Journal of Food Hygiene and Safety
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    • v.35 no.1
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    • pp.83-92
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    • 2020
  • This study investigated the optimal conditions of enzymatic reaction for production of isomaltooligosaccharides (IMO) using rice flour. To manufacture IMO, commercial enzymes (Termamyl 2X, Maltogenase L, Promozyme D2, Fungamyl 800L and Transglucosidase L) were used. The sugar composition and amount of IMO were examined by HPLC with charged aerosol detector (HPLC-CAD) in each manufacturing process. Liquefaction reaction was performed according to different Termamyl 2X concentrations (0.025%, 0.05%, 0.075%, 0.1%) and reaction times (1 h, 2 h). As a result, the reducing sugar content was the highest at 138.26 g/L when 0.075% Termamyl 2X was added for 2 hours. In order to optimize simultaneous saccharification and transglucosylation, experiments on enzyme selection, enzyme concentration and enzyme reaction time were conducted. Reaction with 0.0015% Maltogenase L, 0.05-0.1% Promozyme D2 and 0.1% Tansglucosidase L was effective in decreasing glucose content and increasing content of IMO with a high degree of polymerization. A change in sugar content was observed every 6 hours to determine the optimal reaction time, and the highest IMO was produced after 36 hours of reaction (75.36 g/L). The IMO prepared under optimal conditions showed isomaltose, 35.11 g/L; panose, 11.97 g/L; isomaltotriose, 19.95 g/L; isomaltotetraose, 7.46 g/L; isomaltopentaose, 1.05 g/L at 18 brix and the ratio of IMO in the total sugar was 56.37%.

Case Study on Optimization of Send-out Operation in Liquefied Natural Gas Receiving Terminal (LNG 터미널 송출 운전 최적화 사례 연구)

  • Park, Chansaem;Han, Chonghun
    • Korean Chemical Engineering Research
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    • v.53 no.2
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    • pp.150-155
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    • 2015
  • Recently, LNG receiving terminals have been widely constructed and expanded for an increase in LNG demand. Selection of the storage tank for send-out and estimation of send-out flow rate have significant influence to process operation and economics. In this study, a send-out flow rate of each storage tank is optimized in order to minimize the total BOG generation rate. Considering a size and characteristic of each storage tanks, BOG flow rates are estimated using a dynamic simulation with varying liquid levels in the tanks. The regression model is developed fitting BOG flow rates and tank liquid levels, which are boil off rate model to predict BOG flow rates with particular level data. The objective function and constraints including required total send-out flow rate and level limit in the tanks are formulated to optimize a send-out flow rate of each tank. This method for optimization of send-out operation is applied to the Incheon LNG receiving terminal considering two scenarios for various liquid levels and maximum and minimum required send-out flow rates. For maximum required send-out flow rate, this method achieves BOG reduction of 9% comparing with assumed conventional operation.

Research on Ginseng Production During the Past 20 years (인삼재배 분야의 과거 20년 연구)

  • Park, Hoon
    • Journal of Ginseng Research
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    • v.20 no.4
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    • pp.472-500
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    • 1996
  • Researches on mineral nutrition, physiology and phyrsiological diseases, . cultivaction methods. brceding. pest control quality management and extension during 1976-1995 in Korea were reviewed Review in brceding and pest control was restricted to the researches directely related to cultivaction. Mineral nulrient up take. partion and varicos factors such as top dreasing. Light intersity etc. and interrelationship between minerals were investigated. Top dressing was not effective due to low minera1 requorement Physiological characteristics on tempelature light and water were well elucidated and applied to assess traditional cultivation method and its inovation. Photosyrnthetic pigments. light harvest proteins and activity of related enzymes were studied. In nitrogen metabolism arginine, praline, ammonium, threonine appeared to have important role in re growth of shoot Saponin metabolism was studied in relation to growth and new ginsenosides were found but physiological role of saponin was not clearly elucidated yet Endogenous growth regulators were reported and various erogenous growth regulators were studied for growth stimulation. short stem and seed pruning etc. Various physiological diseases were investigated for cause and control measures were established. Water culture was little studied Forest culture was studied but not retched the recommendable stage Drip irrigation straw mulching. seasonal shading and soil preparation method including soil fertility adjustment were established for practical application. Shading materials completely changed to polyethylene net and materials of polymers The research on ginseng cultivation in paddy field opened the way to establish the permanent ginseng cultivation plantation Ginseng harvester and seeder were developed in the late 1950s. Transplanted and many other machines were developed in the early 1990s. In ginseng breeding only pure line selection was of practical significance several verities were at the stage of seed propagation at ginseng plantations. Mutation breeding (${\gamma}$-ray. X-ray chemicals) was not successful. The research on plantlet formation through tissue culture was a little progressed but still far behind to vegetative propagation. Disease control research was concentrated in the isolation and identification of pathogans. their ecological charactelistics and biological control and soil humigation. Potato root rot nematodes was found and control method was established. Insect and small animal control research was greatly progresses in identification, ecological investigation, and ecological and physical control. Weed control was less important due to the development of mulching method of ridge and ditch. Quality factors of raw ginseng in relation to red ginseng process were extensively studied. Traditional quality measures were elucidated in accordance with modern analytical chemistry resulting in the importance of peptides in the centrat part rather than ginsenosides For large root production growth promoting rootzone micrcorganisms (PGPRM) were isolated and active compounds were identified. Field test on PGPRM was on going. Varictus methods formality improvement through cultivation were developed. Management research of ginseng production was rare Extension was active throuch official and private organizations and through workshop for the extension specialists, and direct lectures to grower's. Extension services made the researcher to understand the existing problems at grower's fields. Research environment for ginseng production was in prime time only for three years when Korea Ginseng Research Institute was established then gradually aggravated.

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Review of Site Characterization Methodology for Deep Geological Disposal of Radioactive Waste (방사성폐기물의 심층 처분을 위한 부지특성조사 방법론 해외 사례 연구)

  • Park, Kyung-Woo;Kim, Kyung-Su;Koh, Yong-Kwon;Jo, Yeonguk;Ji, Sung-Hoon
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.15 no.3
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    • pp.239-256
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    • 2017
  • In the process of site selection for a radioactive waste disposal, site characterization must be carried out to obtain input parameters to assess the safety and feasibility of deep geological repository. In this paper, methodologies of site characterization for radioactive waste disposal in Korea were suggested based on foreign cases of site characterization. The IAEA recommends that site characterization for radioactive waste disposal should be performed through stepwise processes, in which the site characterization period is divided into preliminary and detailed stages, in sequence. This methodology was followed by several foreign countries for their geological disposal programs. General properties related to geological environments were obtained at the preliminary site characterization stage; more detailed site characteristics were investigated during the detailed site characterization stage. The results of investigation of geology, hydro-geology, geochemistry, rock mechanics, solute transport and thermal properties at a site have to be combined and constructed in the form of a site descriptive model. Based on this site descriptive model, the site characteristics can be evaluated to assess suitability of site for radioactive waste disposal. According to foreign site characterization cases, 7 or 8 years are expected to be needed for site characterization; however, the time required may increase if the no proper national strategy is provided.

Exercise Effect Applied to Patients Who Underwent Lung Resection with Lung Cancer: Systematic Review and Meta-Analysis (폐암으로 폐 절제술을 시행한 환자에게 적용한 운동 효과: 체계적 문헌고찰과 메타분석)

  • Park, Young-Joo;Bae, Phil-Won
    • The Journal of the Korea Contents Association
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    • v.18 no.6
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    • pp.652-666
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    • 2018
  • The purpose of this study was to investigate systematic review and meta-analysisto identify exercise intervention effect applied to patients who underwent lung resection with lung cancer. A total of 1,322 publications were searched from 1990 to 2016 through domestic and foreign electronic databases, and the final 13 publications were selected through literature selection process. Finally, eight RCT (randomized controlled trial) and five NRCT (non-randomized controlled trial) were identified, including 925 participants. The results of the meta-analysis of the effect sizes of the intervention on the outcome variables showed that the health-related quality of life EORTC QOL-C13/30 (the European Organization for Research and Treatment of Cancer Core Quality of Life Questionnaire) (MD-0.50 95 % CI -0.83-0.18) and SF-36 PCS (the Medical Outcomes 36-Item Short Form Health Survey PCS) (MD 0.75, 95 % CI 0.41-1.10) in the intervention group were significantly higher than the control group. The results of this study suggest that exercise interventions can potentially improve the quality of life of patients who underwent lung resection with lung cancer.

What Drives International Science and Technology Cooperation? (과학기술분야 국제협력 필요성의 인식에 대한 연구: 거래비용이론, 성과측청관점, 지식기반관점을 중심으로)

  • Shin, Hyung-Deok;Chung, Tae-Young;Ryu, Choon-Ho;Lee, Joung-Ho
    • Journal of Korea Technology Innovation Society
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    • v.13 no.4
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    • pp.638-655
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    • 2010
  • The importance of international science and technology cooperation is growing more and more, but we do not know much about what criteria could be used to choose a science or a technology that needs international cooperation first and foremost among many kinds of competing sciences and technologies. Moreover, this selection process is affected by evaluators' or science/technology experts' perception, but we do not quite know what they actually see when they evaluate the needs of international cooperation. This study investigates the conditions that international science and technology cooperation is encouraged by scholars and researchers in various areas. Based on theoretical arguments of Transaction Cost Economics, Measurement View, and Knowledge-Based View, we drew hypotheses on when experts perceive greater needs of international cooperation. Using the classification categories of 10 major sciences and technologies, we collected data from 151 respondents from scientists in research institutions and colleges. As a result, we found that experts in science and technology areas perceive strong needs of international cooperation when the importance of focal science or technology is high and the relative national level of focal science or technology is low. Also, we found that the importance and relative level of focal science and technology have positive moderating effects each other. Lastly, we found that when experts evaluate their own major areas, the strength of positive relationship between the importance of science and technology and needs of international cooperation is diminished.

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