• 제목/요약/키워드: Commercial soil

검색결과 452건 처리시간 0.026초

해상풍력타워용 버켓기초의 좌굴거동 (Buckling Behaviors of Bucket Foundation for Offshore Wind Tower)

  • 이계희;짠득푸
    • 한국해안·해양공학회논문집
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    • 제25권3호
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    • pp.123-127
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    • 2013
  • 본 논문에서는 해상풍력발전터빈의 기초형식 중 하나인 버켓기초의 관입시 발생할 수 있는 좌굴거동에 대한 연구를 수행하였다. 유한요소를 사용하여 대상구조물을 모델링하고 현재 설계기준의 기본인 원통형 쉘의 좌굴거동을 해석하여, Batdorf의 계수에 따라 설계기준에 제시된 식과 비교하여 모델의 검증을 수행하였다. 검증된 해석 모델을 바탕으로 인접한 지반의 영향 및 하중조건을 적용하고 종방향보강재와 관입깊이가 좌굴성능에 미치는 영향을 평가하였다. 평가결과 종방향보강재의 적용은 특정영역에서 좌굴강도를 크게 증가시키고 인접한 지반의 영향은 관입에 따라 선형적으로 증가하는 것으로 나타났다.

재배년수에 따른 인삼의 생육특성, 생리활성, 성분의 변화 (Changes in Growth Characteristics, Biological Activity and Active Compound Contents in Ginseng of Different Ages)

  • 문지원;장인배;유진;장인복;서수정;이성우
    • 한국약용작물학회지
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    • 제27권6호
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    • pp.383-389
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    • 2019
  • Background: Ginseng has been used as a medicine and functional food since ancient times. It is a perennial crop, and its whose commercial valuse increases with growing period and is affected by the atmosphere and soil environment. Methods and Results: In a selected field, we measured air temperature under a shade structure and soil physicochemical properties, and determied plant and root growth as well as ginsenoside and total polyphenol content of one- to five-year-old ginsengs plants. Although air temperature above 30℃ was recored for more than 37 days, no marked growth inhibition of ginseng was detected. Among all soil physicochemical properties, except for pH, were within the allowable range the shortage increases with ginseng years. In five-year-old ginseng, the quantity is about 9.7% higher than the average weight by standard, indicating that is not affected by temperature when grown under a shade structure. Three-year-old ginseng contained the highest total ginsenoside and total polyphenol levels and exhibited the greatest DPPH radical scavenging activity. Conclusions: The total ginsenoside and protopanaxadiol/protopanaxatriol ratio were both low at five-year-old ginseng plants, which was attributed to rapid growth of the root system in five-year-oid plants. There were no significant differences in total polyphenol content and antioxidant activity between.

토양 metagenome library로부터 혈전용해효소의 탐색 (Screening of Fibrinolytic Enzymes from Soil Metagenome Library)

  • 이선이;김보혜;강주형;조효진;공은희;문상욱;김영진;안순철
    • 생명과학회지
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    • 제16권2호
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    • pp.360-364
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    • 2006
  • Fibrin clots of blood vessels are one of the serious factor caused cardiovascular disease. The development of a antithrombotic and thrombolysis solvent is necessary to prevent and treat these diseases. It has been reported that a strong fibrin-specific fibrinolytic enzyme was produced from a Korean fermented soybean paste similar to Japanese miso. We have been screened the known or novel fibrinolytic enzymes by activity-based and sequence-based screening from soil DNA metagenome library containing all kinds of environmental genomic DNA. The activity-based screening was determined the protease activity on 0.5% skim milk. For sequence-based screening, we designed a set of primer expanding gene sequence of fibrinolytic enzyme, performed PCR and selected clones showing the expected size of amplicons from metagenome library. Transformation of the gene encoding fibrinolytic enzyme was carried out with commercial vectors and their transformants were selected. Finally, we found 15 positive clones from metagenome library. Then each of sequences were analyzed and identified as similar or known the clones of nattokinase. We are going to perform full sequence of each clones, ligate with expression vector, transform into competent cells and then determine activity of expressed enzymes.

수치해석을 통한 상향식 배수겸용 쏘일네일링에 대한 강우모형사면 거동 연구 (Numerical Analysis on the Behavior of a Slope with Upward Drainable Soil Nails during Rainfall)

  • 김영남;이철규;이강일
    • 한국지반신소재학회논문집
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    • 제13권1호
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    • pp.11-22
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    • 2014
  • 본 연구는 보강과 동시에 수평배수를 겸용하는 상향식 쏘일네일에 대한 지반거동을 파악하기 위해서 모형실험과 수치해석을 이용하여 그 거동을 연구하였다. 모형실험은 모형토조 내에 상대밀도 및 강우강도 조건별로 풍화토 지반의 모형사면을 만들고 그 위에 인공강우를 뿌리는 실험을 통해 쏘일네일을 설치하지 않는 무보강조건과 배수기능을 겸한 상향식 쏘일네일을 설치하는 보강조건으로 나누어 실험을 실시하였다. 또한 실험결과를 검증하기 위하여 침투해석 프로그램인 SEEP/W를 사용하여 모형실험이 시행된 조건으로 침투해석을 실시하고 그 결과를 비교분석하였다. 본 연구 결과 강우로 인한 지하수위와 간극수압의 변화는 수치해석의 경우는 지체시간이 없이 변화되는데 비하여 모형실험은 지체시간이 있는 상태로 나타났지만 전반적으로 최종 도달시점의 측정값은 유사하게 나타나 수치해석으로 모형지반을 모사할 수 있었다.

폐수처리 슬럿지와 퇴비 및 목탄의 화학적 특성과 구조에 관한 연구 (A Study on the Chemical Composition and Structure of Sludge, Compost and Charcoal)

  • 임기표;위승곤
    • 펄프종이기술
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    • 제35권1호
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    • pp.27-32
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    • 2003
  • To understand the chemical structure of sewer sludge in comparison with commercial compost and charcoal used as a soil improver, it was carried out to analyse their ash contents and metal ions, and to elucidate the chemical structure of their residuals after a sequential treatment of alcohol-benzene(1:2) extraction in Soxhlet, 3% HCl reflux and 79% H₂SO₄ hydrolysis, using CHNS analyzer and solid C-13 NMR spectrometer. The results obtained were as follows: 1. Ash content of sludge was about 46% that is higher than those of compost (17%) and charcoal (4%). 2. The residual of sludge after a sequential treatment of HCl and H₂SO₄ hydrolyses had high ash content about 23%, too. 3. The sludge seems to be suitable to the soil improver because the content of heavy metal ions in sludge was near the compost and below the organic fertilizer standard. 4. Elemental composition of sludge residual after HCl-H₂SO₄ hydrolyes was C/sub 56/H/sub 91/O/sub 12/N₂S = (C/sub 6/H/sub 10/O/sub 5/)/sub 7/(C/sub 6/H₄)/sub 7/C₂H/sub 43/O₂N₂S, similar to C/sub 103/H/sub 122/O/sub 33/N/sub 6/S = (C/sub 6/H/sub 10/O/sub 5/)/sub 6/(C/sub 6/H₄)/sub 10/C/sub 7/H/sub 22/O₃N/sub 6/S of compost. 5. The sludge residual had proved to have both considerable aliphatic and aromatic groups, but the compost residual to have mainly aliphatic groups and the charcoal to have mainly aromatic groups, through the peak analysis of solid C-13 NMR charts. 6. So, the sewer sludge is proved to have a considerable amount of aromaticity like in woody biomass containing lignin.

강우량이 극히 적은 여건에서의 인삼재배의 순응 : 캐나다 브리티쉬 콜롬비아의 실례 (The Adaptation of Ginseng Production of Semi-arid Environments : The Example of British Columbia, Canada)

  • Bailey, W.G.
    • Journal of Ginseng Research
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    • 제14권2호
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    • pp.297-309
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    • 1990
  • Ginseng is renowned for both its medicinal and herbal uses and successful cultivation of Panax ginseng in Asia and Panax Vtiinvtiefolilim in North America has until recently taken place in the native geographical ranges of the plants. As a consequence of the potential high capital return and anticipated increases in consumer consumption, commercial cultivation of American ginseng now occurs well outside the native range of the plant in North America. In fact, the region of greatest expansion of cultivation is in the semi-arid interior region of British Columbia, Canada. Linked with this expansion is the potential domination of the ginseng industry by agricultural corporations. In the interior of British Columbia, the native decidous forest environment of eastern North America is simulated with elevated polypropylene shade and a sllrface covering of straw mulch. The architecture of these environments is designed to permit maximillm machinery useage and to minimize labour requirements. Further, with only a four-year growth cycle, plant densities in the gardens are high. In this hot, semiarid environment, producers believe they have a competitive advantage over other regions in North America because of the low precipitation rates. This helps to minimize atmospheric humidity such that the conditions for fungal disease development are reduced. If soil moisture levels become limited, supplemental water can be provided by irrigation. The nature of the radiation and energy balance regimes of the shade and much environment promotes high soil moistilre levels. Also, the modified environment reduces soil heating. This can result in an aerial environment for the plant that is stressful and a rooting zone environment that is sub-optimal. The challenge of further refining the man modified environment for enhanced plant growth and health still remains.

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Production of liquid fertilizer from broken eggs and evaluation of its effect on lettuce growth

  • Kim, Bo-Ra;Lee, Jae-Han;Kim, Su-Hun;Choi, Ha-Yeon;Choi, Bong-Su;Oh, Taek-Keun;Lee, Chang-Hoon
    • 농업과학연구
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    • 제47권1호
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    • pp.11-18
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    • 2020
  • Eggs are likely to be used in agriculture because they can provide enough nutrients for crop growth. Statistics show that a large number of eggs are lost due to breakage before reaching the final consumer. The purpose of this study was to make a natural liquid fertilizer as a substitute for chemical fertilizers using broken eggs as a resource and to evaluate the efficiency of the formulated fertilizer. To make the liquid fertilizer, the broken eggs and distilled water were mixed at ratios of 6 : 4 and 4 : 6. Then, effective micro-organisms (EM) and sugar were added, and the mixture was fermented. The temperature and electrical conductivity (EC) increased gradually with the fermentation while the pH decreased. When evaluated following the seed germination index method of the compost, it was found that the fertilizer matured 10 days after the beginning of the experiment. The growth experiment was conducted with lettuce in which the fermented liquid fertilizer was compared with a commercial liquid fertilizer. The 6 : 4 treatment produced plants with the densest fresh shoot and roots weighing 41.6 and 4.6 g, respectively. The number of leaves (12.3 per plant) was also the highest for the 6 : 4 treatment. Soil analysis showed that the soil pH was improved, and the soil organic matter was increased in the fermented liquid fertilizer treatment.

지진파의 주파수 특성에 따른 지반-말뚝-구조물 상호작용계의 거동 특성 분석 (A Study of Characteristics of Soil-Pile-Structure Interaction Behavior on the Frequency Contents of the Seismic Waves)

  • 이종우;이필규;김문겸;김민규
    • 한국전산구조공학회논문집
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    • 제17권3호
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    • pp.295-308
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    • 2004
  • 본 연구에서는 기 개발된 유한요소-경계요소 조합을 통한 지반구조물 상호작용해석기법을 이용하여 주파수 특성이 다른 여러 가지 지진파를 이용한 수치해석을 통하여 지진파에 따른 거동특성을 분석하였다. 사용한 기본해의 검증을 위하여 적용된 다층 반무한 해를 Estorff 등의 연구결과와 비교하였으며, 기본해를 이용하여 개발된 지반-구조물 상호작용해석기법의 검증을 위하여 자유장해석을 수행하였다. 자유장 해석결과는 1차원 파전달 이론에 의하여 개발된 자유장응답해석 프로그램인 SHAKE의 결과와 비교하여 그 타당성을 검증하였다. 검증된 해석기법을 이용하여 특성이 다른 3종류의 지진파가 적용된 2차원 평면상의 지반-구조물 상호작용해석을 수행함으로써 지진파와 말뚝유무에 따른 지반-구조물 상호작용거동특성을 분석하였다. 해석결과 지진이 작용할 때는 말뚝기초를 사용하는 것이 반드시 유리한 결과를 주지는 않는다는 것을 알았으며, 지반의 비선형성을 고려 할때는 말뚝의 유무가 지진응답결과에 큰 영향을 미치지 않는다는 것을 알 수 있었다.

시설과채류(오이, 참외)의 뿌리혹선충 종합방제에 관한 연구 (Study on Integrated Control against Root-knot Nematode of Fruit Vegetables (Oriental Melon and Cucumber) in Vinyl House)

  • 박소득;박선도;권태영;최부술;이원식;최영연
    • 한국응용곤충학회지
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    • 제34권1호
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    • pp.75-81
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    • 1995
  • 시설 과채류 재배지의 뿌리혹선충의 피해경감을 위해서 경북도내 시설 오이 재배단지인 칠곡과 참외재배 주산지인 성주에서 1992년부터 1994년까지 3년간 방제시험한 결과 뿌리혹선충의 피해를 경감시키기 위한 토양개량 적기는 모래산흙인 마사토의 경우에 3년 붉은산흙인 경우 4년마다 하는 것이 효과적이고 농약과 조합한 오이의 방재시험에서 빗사마드 분제가 78.2%, 카보입제+토양반전+담수가 71.2%, 카보입제+담수가 66.3%이었으며 참외에서 살충제처리후 20일에는 77.7~80.6%의 방제효과를 보였으나 60일 후에는 33.7~49.5%로 방제가 낮아 후기에는 효과가 낮았다. 참외재배 논에서의 작부체계에 따른 뿌리혹선충 밀도 억제효과는 참외 재배후 담수하여 벼를 재배할 때에 벼 수확시 방제효과가 91.1%로 대부분의 선충이 사멸되었다. 각 처리구 공히 처리당시에는 뿌리혹선충 증식을 억제하였으나 생육추기로 갈수록 선충밀도가 증가되었다. 그러나 토양개량은 3년간 효과적이였으며 가장 경제적으로 선충의 증식을 억제하 수 있는 처리는 3년마다 한번씩 벼를 재배하는 것이었다.

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유기질 비료의 시용이 배 과원의 토양과 엽과 눈 특성에 미치는 영향 (Effects of Compost Application on Soil Properties and Leaf and Bud Characteristics of Pear Trees in Orchard Farms)

  • 이재안;김월수;최현석
    • 한국유기농업학회지
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    • 제17권4호
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    • pp.567-575
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    • 2009
  • 본 실험은 미생물이 포함되어있는 환경 친화적인 상업용 유기질비료(compost)를 2년 동안시용함으로서, 토양 내 화학성과 '신고' 배 수체생장을 향상시킬 수 있는 지를 알아보기 위하여 수행하였다. 시판된 유기질 비료 처리는 토양 내 미생물생체량과 토양 pH, 유기물함량, 그리고 양이온 치환용량을 관행재배 구에 비해서 증가시켰다. 유기질 비료 처리에 의해 개선된 토양환경은 엽 내 무기성분 함량에는 크게 영향을 미치지 못했으나, 엽 두께를 증가키시고, 엽과 꽃눈 수를 증가시킴으로서, 배 수체생장에 크게 영향을 미친 것으로 판단된다.

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