• Title/Summary/Keyword: Plastic-house

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A 3D-Structural Beam Optimization for a VENLO-Type Plastic-Film House using Computer Aided FEM (전산유한요소를 이용한 벤로형 플라스틱필름온실의 3D 구조재 최적 설계)

  • 김경원;김만수;윤진하;전종길;이인복
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 2003.07a
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    • pp.360-365
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    • 2003
  • 최적화의 개념은 목적에 따라 다양하겠으나 수치해석에서는 기본적으로 설계변수를 움직여 목적함수를 최소화 혹은 최대화하는데 있다. 열전달에서는 최소온도, motor를 설계할 때는 최대토크 등이 있고, 구조물설계에 있어서는 최소무게(Weight or Volume) 혹은 최대의 Frequency를 구하는데 최적화 수치해석이 이용되고 있다. 오늘날 컴퓨터하드웨어의 발달과 더불어 전산수치해석의 영역이 급속히 높아져가고 있으며 PC에서의 계산처리능력이 90년대의 work station급을 초가 함으로써 보다 쉽게 전산수치해석이 가능하게 되었다. (중략)

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Distribution Characteristics of a Mini -Sprinkler without a Bridge (Non-bridge 형 미니스프링쿨러의 살수 특성)

  • 이남호
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.42 no.1
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    • pp.66-72
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    • 2000
  • A study was conducted to find distribution patterns of minisprinkler without a bridge for the desing of microirrigation systems. The experiments were executed in a plastic house to minimize the effect of the wind. Data were collected at four different operation pressures and at 3 different riser heights. Sprayed water were collected by aluminium cans with 65mm diameter and 100mm height placed at 0.3m grid spacing . A schematic distribution pattern with distance from a minisprinkler was suggested for the layout design of the minisprinkler. Distribution pattern of the minisprinkler was found irregular in space. Distributin performance characteristics of the minisprinkler such as effective radius. , effective area, mean application depth, absolute maximum application depth, effective maximum application depth and coefficient of variation were determined. It was indicated that there is a trend of decrease in variation coefficient adn better water distribution by the increase in operation pressures and riser heights.

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A Study on the Dry-Shrinkage Properties For Floor Mortar With Crack-Reducing (균열저감형 바닥마감전용 모르터의 건조수축특성 연구)

  • 이종렬;이웅종;채재홍;박경상;김기수
    • Proceedings of the Korea Concrete Institute Conference
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    • 1999.04a
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    • pp.175-180
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    • 1999
  • The heating system of korea apartment house is called Ondol. The surface finishing mortar of this floor system typically used the cement based mortar, where the surface finishing mortar easily appears the crack. To order to crack control, the cement that added expansive additive used to reducing dry-shrinkage. For the surface finishing mortar, the types of shrinkage is known as plastic shrinkage, dry-shrinkage and autogenous This experimental study is to investigate the difference on dry-shrinkage of the cement that added expansive additives and OPC. The test method is varied the ration of water/cement (W/C) and the ratio of sand/cement(S/C). For OPC, The increase of the ratio of S/C is reduced dry-shirnkage but for the cement that added expansive additives, the increase of the ratio of S/C is augmented dry-shrinkage For OPC, The increase of the ratio of W/C is augmented dry-shrinkage but for the cement that added expensive, the increased of the ratio of W/C is reduced dry-shrinkage.

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Effect of Anti-dropping on Environmemt and Oriental Melon(Cucumis melo L) in Plastic Films House. (연질필름 피복시설내 방적처리가 시설환경 및 참외 생육에 미치는 영향)

  • Jeon, Hee;Kwon, Young-Sam;Kim, Hyun-Hwan;Lee, Si-Young
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 1997.05a
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    • pp.53-58
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    • 1997
  • 시설내 방적처리별 광환경, 개선 효과는 수적율이 환기나 송풍 단독으로 처리한 경우보다 2.6-5.8% 가량 낮은 2.7%를 보여 투광율이 송풍, 환기 단독 처리구보다 2.7-4.9% 가량 높아 67.4%를 보인 송풍+환기개선처리에서 가장 우수하였고 하우스 공간에서의 정식후 6일간 적산최저기온은 무처리에 비하여 4.6$^{\circ}C$가 낮았으나 작물이 정식된 터널에서는 0.8$^{\circ}C$ 정도 낮았다. 참외의 생육은 환경이 방적효과로 광환경이 우수한 송풍+환기개선처리에서 두 처리보다 엽수가 3-5매 가량 많고 착과율도 4-8% 정도 높아 전체적인 수량이 3,630kg/10a로 무처리에 비하여 43%나 증수되었다.

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Bacterial Node Soft Rot of Pepper (Capsicum annuum L.) Caused by Erwinia carotovora subsp. carotovora (Erwinia carotovora subsp. carotovora에 의한 고추 마디 무름병)

  • 정기채;임진우;김승한;임양숙;김종완
    • Korean Journal Plant Pathology
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    • v.14 no.6
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    • pp.741-743
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    • 1998
  • A bacterial disease of pepper (Capsicum annuum L.) that rooted the stem nodes to black was found in pepper plants which cultivated in plastic house at Chungdo, Kyungpook, Korea in March, 1998. Bacterial isolates derived from the diseased peppers were pathogenic to potato, eggplant and Chinese cabbage but, was not pathogenic to chrysanthemum by artificial inoculation. On the basis of bacteriological characteristics and pathogenicity test on host plants, the causal organism of the node soft rot of pepper is identified as Erwinia carotovora subsp. carotovora and the name of disease is proposed as bacterial node soft rot of pepper.

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Estimating upland crop water use in Jeju (제주도 밭작물 용수량 산정방법)

  • Lee, Yong-Il;Kim, Hyeon-Soo;Lim, Han-Cheo;Song, Chang-Khil;Moon, Kyung- Hwan;Kang, Bong-Kyoon
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2005.10a
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    • pp.32-37
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    • 2005
  • Crop evapotranspiration rates of the garlic, potato and carrot were measured in a lysimeter at the National Institute of Subtropical Agriculture. The crop coefficients were calculated using the values of the actually measured evapotranspiration(ETcrop) and the reference crop evapotranspiration (ETo) estimated by the Penman-Monteith equation. The maximum crop coefficients of the garlic, potato, carrot and cabbage were 1.07, 1.07, 0.73 and 0.92 respectively. For the Citrus Aoshima Unshiu and Hallabong in the plastic house, the maximum crop coefficients were 1.38 and 1.29 respectively. Computer program using EXCEL was also developed to estimate the crop water use.

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Investment beneficial analysis of rice alternative plants

  • Yi, Hyang-Mi;Goh, Jong-Tae;Lee, Jong-In
    • Korean Journal of Agricultural Science
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    • v.40 no.2
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    • pp.169-176
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    • 2013
  • The price and revenue of rice are expected to decrease due to increasing rice imports, decreasing consumption and the discontinuance of the government's rice procurement. This degenerating profitability is leading to a rise in the cultivation of upland-crops such as beans, fodder crops and fruits in paddy fields. However, there is a lack of research on the selection of rice substitute crops which are adaptable to the relevant region through profitability analysis. This research, therefore, analyzed investment profitability of rice substitute crops for Cheorwon-gun area in Kangwon province. The study applied net present value (NPV) and internal rate of return (IRR), which fit for mutually exclusive investments that make one selection to the exclusion of other crops. Target crops are green house plants in Cheorwon-gun area. Financial analysis showed paprika and cucumber have investment feasibility for automated vinyl greenhouses and conventional plastic greenhouses respectively.

A Study on the Plan (무동 스튜디오(Meudon Studio)에 관한 연구)

  • Choi, Jae-Suk
    • Journal of architectural history
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    • v.1 no.1 s.1
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    • pp.191-204
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    • 1992
  • This study is done in order to settle down as a Architecture Movement mainly had conducted by Theo van Doesburg. The process of this research is mainly focus on the Theo van Doesburg had used it as a house and studio, which had built in November 1930 since Agust 1925. Even though the works and theories of Theo van Doesburg had widely inffuenced on Modern Architects, these were the only experimental paper architecture by conceptural proposal of plastic architecture. Namely, The value of his works and theories did not overcome experimental archtecture. but, Theo van Doesburg left one work, at Meudon near Paris. This study intends to clear the special features of changing process and spatial characteristics on planing throughout from the planning to accomplisment of it.

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The study on the environmentally friendly recycling method of CFRP (환경성을 고려한 폐 복합재료(CFRP)의 재활용기법에 대한 연구)

  • Lee, Cheul-Kyu;Kim, Yong-Ki;Phirada, Pruitichaiwiboon;Kim, Jung-Suck;Ju, Chang-Sik
    • Proceedings of the KSR Conference
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    • 2008.11b
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    • pp.1803-1806
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    • 2008
  • Various efforts of reducing the green house gas in the whole industrial fields including railway industry have been implemented. Tilting train is the key example because it can run more faster on the existing rail than others due to its composite body. The system has an advantage of light weight but also a task to solve, recycling of composite material. To recycle the CFRP(Carbon Fiber Reinforced Plastic), there are two typical methods; chemical and thermal method. In this study, more environmentally friendly recycling method was recommended through the environmental function through comparing both recycling methods.

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