• Title/Summary/Keyword: water-reducing

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Development of the Automatic Turnout (자동 분수공의 개발)

  • 저하우;이남호;김성준;최진용;한형근;한휘남
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.36 no.4
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    • pp.33-38
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    • 1994
  • Floating-type automatic turnout was developed for the purpose of reducing labor cost and labor-working hours related to turnout management. The point of automation is to use a flexible-float within the turnout. The weight of float is changed by emptying and filling with water at the beginning and ending of irrigation. The turnout is controlled to open and close small bole on the float bottom using electromagnets. With the weight control of float. the gate of turnout is opened by the empty float to begin irrigatiom and is closed by the filled float to stop irrigation. The turnout was designed to be operated by the main computer and to minimize electric power consumption by sending an electric current at the beginning and ending of irrigation. The functional experiment was succesfully carried out and the rating curves for both free overflow condition and submerged flow condition were derived.

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EFFCTS OF TILLAGE SYSTEMS ON THE QUALITY OF RUNOFF FROM SLUDGE-AMENDED SOILS

  • Mostaghimi, Saied;Bruggeman, Adriana C.
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1993.10a
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    • pp.984-993
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    • 1993
  • land application of sewage sludge requires careful monitoring because of its potential for contamination of surface water and groundwater. A rainfall simulator was used to investigated the effects of freshly applied sludge on runoff of sediment and nutrients from agricultural crop lands. Rain was applied to 16 experimental field plots. A three run sequence was used to simulate different initial moisture conditions. Runoff, sediment and nutrient losses were monitored at the base of each plot during the simulated rainfall events. Sludge was surface applied and incorporated at conventionally -tilled plots and surface applied at no-till plots, at rates of 0, 75, 150 kg-N/ha. No-till practices greatly reduced runoff, sediment , and nutrient losses form the sludge treated plots, relative to the conventional tillage practices. Incorporation of the sludge was effective in reducing nutrient yields at the conventionally-tilled plots. This effect was more pronounced during the third rain torm, with wet initial conditions. Peak loadings of nutrients appeared during the rainstorm with wet initial conditions.

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Nitrate and Pesticide Losses Under Various Cropping Management Systems

  • Kent Mitchell, J.;Felsot, Allan;Hirschi, Michael C.;Lesikar, Bruce J.
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1993.10a
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    • pp.1003-1012
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    • 1993
  • The objective of this study was to evaluate the effectiveness of tillage and cropping management systems in reducing the movement of nitrate and pesticides in surface and sub-surface flow. Nitrate and pesticides in runoff and sub-surface tile flow have been monitored for two years from fields with various tillage and cropping management practices. Samples have also been obtained along the mainstream of the watershed. Concentrations of nitrate an pesticides differed little among specific sampling locations along the river, but they definitely followed a seasonal cycle. Nitrate concentrations from the tile drains varied considerably between fields depending upon the cropping management systems used, with concentrations varying seasonally as inthe river.

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Evaluation on SGBD demineralizers and Optimized Cation/Anion Resin ratio in PWR NPPs

  • Sung Ki-Bang;Nam Yong-Jae;Lee Jae-Sung
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2005.11a
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    • pp.79-86
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    • 2005
  • In PSR on the Kori 3&4 NPP, The low level radioactive waste resin from SGBD demineralizer is more than $65\%$ of total waste resin in NPP So, it needs to be improved. The secondary cooling water pH control methods are used ammonia-AVT from the first. According to changing ETA which is better than ammonia, SGBD cation load is increased about 2-3 times. Waste resin product is also increased in proportion to the SGBD cation load. To reduce the waste volume, new cation resin exchange criteria is confirmed that demineralizer is almost saturated.

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Electro-chemical Mechanical Deposition for Planarization of Cu Interconnect (Cu 배선의 평탄화를 위한 ECMD에 관한 연구)

  • Jeong, Sukhoon;Seo, Heondeok;Park, Boumyoung;Park, Jaehong;Park, Seungmin;Jeong, Moonki;Jeong, Haedo;Kim, Hyoungjae
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.18 no.9
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    • pp.793-797
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    • 2005
  • This study introduces Electro-chemical Mechanical Deposition(ECMD) lot making Cu interconnect. ECMD is a novel technique that has ability to deposit planar conductive films on non-planar substrate surfaces. Technique involves electrochemical deposition(ECD) and mechanical sweeping of the substrate surface Preferential deposition into the cavities on the substrate surface nay be achieved through two difference mechanisms. The first mechanism is more chemical and essential. It involves enhancing deposition into the cavities where mechanical sweeping does not reach. The second mechanism involves reducing deposition onto surface that is swept. In this study, we demonstrate ECMD process and characteristic. We proceeded this experiment by changing of distribution of current density on divided water area zones and use different pad types.

Studies on the Quality Evaluation and Metal Content of Asp. Rhi. Bac. sp. Fermented Denjang added Mulberry Leaves in Sanitary Canned. (위생캔으로 제조한 상엽첨가 Asp. Rhi. Bac.속 발효된장의 품질평가와 금속물질 함량에 관한 연구)

  • 허윤행
    • Journal of environmental and Sanitary engineering
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    • v.19 no.1
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    • pp.42-49
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    • 2004
  • The study was carried out in order to improve the quality of fermented soybean, that is, Doenjang with strain ,mold and bactea, added mulberry leaves powder were investigated and analyzed as follows. 1. The water content of samples was 38.51-50.10%, pH value 5.44-6.21 and total acidity, 2.42-3.13 2. The reducing sugar of content for samples was 7.01-7.24% on contrast mulberry added sample was 8.34-12.11%, Amino-N as contrast 5.96-7.63% mulberry added, 8.34-12.11% 3. In sensory evaluation test, excellent results was 2% added sample than others. 4. The heaby metals analyzed form samples cans, iron, tin and lead content of samples were 5.63-6.03 ppm, 31.70-35.53 ppm and trace.

Studies on the Quality Evaluation and Metal Content of Fermented Doenjang added Green Tea Powder in Sanitary Canned (위생 캔으로 제조한 녹차첨가 발효된장의 품질평가와 금속물질 함량에 관한 연구)

  • Heo, Yun-Haeng
    • Journal of environmental and Sanitary engineering
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    • v.22 no.1 s.63
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    • pp.37-47
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    • 2007
  • In order to improve the Quality of fermented soybean Doenjang was investigated. The samples were prepared and fermented by the koji made with A. oryzae, B. subtilis and B. natto strains, that the product added green tea powder with sanitary canned food. 1. The water content of sample was 50.30-42.14%, pH value 6.03-5.52 and total acidity, 3.01-3.87. 2. The reducing sugar content for samples was 9.35-7.81%, Amino-N, 7.96-9.21%. 3. In the sensory evaluation test, the good sensory qualify that was S-2 sample than to S-1 and S-3. 4. The heavy metals analyzed from sample cans, tin, iron and lead content were 27.31-29.04 ppm, 5.32-5.91 ppm and trace amount.

Myocardial Protective Effect of Adenosine in Ischemic Rat Heart (흰쥐의 허혈심장에서의 Adenosine의 심근 보호 효과에 관한 연구)

  • 박승규
    • Journal of Chest Surgery
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    • v.23 no.6
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    • pp.1090-1106
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    • 1990
  • This study was undertaken to investigate whether adenosine administered during cardioplegic arrest could enhance myocardial protection and improve recovery of function after ischemia. Isolated Langendorff-perfused rat hearts were subjected to 40 minutes of normothermic [37oC] ischemia. Control hearts [n=10] received modified St. Thomas’ cardioplegic solution, and the remaining hearts received modified St. Thomas’ cardioplegic solution with either 20 \ulcornerM [n=10], 200 \ulcornerM [n=10] adenosine. After ischemia of 40 minutes and 30 minutes of reperfusion, left ventricular contractility was superior in all groups of adenosine-treated hearts compared with control hearts. Furthermore, there was a significant incremental increase in functional recovery with increasing dose of adenosine. Post-ischemic diastolic stiffness was significantly better in all adenosine groups compared with controls. No differences were noted in coronary flow or myocardial water content between adenosine-treated and control hearts. These data demonstrate that adenosine administered in these concentrations provides myocardial protection, preservation of myocardial ATP and creatine phosphokinase and improved post-ischemic functional hemodynamic recovery after normothermic ischemia, presumably metabolically by reducing depletion of adenosine triphosphate, inducing rapid cardiac arrest and enabling improved post-ischemic recovery.

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The Effectiveness of a Child-Care Centers' Based Parent Education Program on Environmental Preservation (유아교육기관의 환경보전 부모교육프로그램 효과연구)

  • Choi, Kyung Sun;Cha, Mi Young
    • Korean Journal of Child Studies
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    • v.25 no.4
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    • pp.177-190
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    • 2004
  • Training for mothers and children first included information on water, ground, and air pollution, saving energy, and reducing trash. In the second phase, the family followed steps outlined in an environmental preservation guidebook. The experiment was of 16 weeks duration, conducted with 120 subjects, comprised of sixty 4-year-old children and their mothers. Measures included environmental preservation knowledge and the actual practice of environmental preservation on the part of the subjects. Mothers performed self-evaluations while teachers measured the children. SPSS was used for data collection and analysis. The results of this study indicate that the program increased perceptions on environmental preservation and the actual practice of the experimental group. The program application also resulted in meaningful co-relationships between perceptions and practice and between mothers and their children.

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Durability of the Solidified Mine Tailing-Hydrated Lime Mixture Against Repeated Freezing and Thawing (폐광미-소석회 고화체의 동결융해 내구성에 관한 연구)

  • Min, Kyoung-Won;Lee, Hyun-Cheol;Kim, Tae-Poong
    • Journal of Industrial Technology
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    • v.28 no.B
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    • pp.65-69
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    • 2008
  • The tailings piled in abandoned mines are well-known potential sources of soil contamination. Hydrated limes were applied as cementing materials to solidify heavy metal contaminated tailings for the purpose of reducing their toxicity and migration rates. The optimum mixing ratio of tailings, hydrated lime, and water was determined through a preliminary test. The mixtures of mine tailings and hydrated lime solidified through pozzolanic reaction were tested for their durability against repeated freezing and thawing processes. After repeated freezing and thawing, the uniaxial compressive strengths of all the solidified mixture specimens decreased in comparison with those before test but still higher than $3.5kgf/cm^2$, the standard recommended for land reclamation solids by EPA(Environmental Protection Agency), which suggested that hydrated lime be a potential material to treat the abandoned mine tailings for the environmental purpose.

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