• Title/Summary/Keyword: 광폭 온실

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Effect of roof slope on the transmissivity of direct and diffuse solar radiation in multispan glasshouse by a computer simulation (컴퓨터 시뮬레이션에 의한 연동 유리온실내의 직달일사 및 산란일사 투과율에 미치는 지붕경사각의 영향)

  • 김용현;이석건
    • Proceedings of the Korean Society for Bio-Environment Control Conference
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    • 1998.05a
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    • pp.27-32
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    • 1998
  • 국내에 보급되어 있는 유리온실은 네덜란드에서 수입된 벤로형(Venlo type or Dutchlite)과 벤로형에 비해서 동고가 높으며 온실 한 동의 폭이 상대적으로 큰 광폭형(widespan type)이 대부분을 차지하고 있다. 벤로형 은실의 측고는 3.5~4.0m로서 다소 차이가 있으나, 한 동의 폭과 지붕경사면의 길이가 일정하기 때문에 온실의 지붕경사각은 대부분 22$^{\circ}$를 나타낸다. (중략)

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Analyses of Actual State and Structural Safety of Regionally Characterized Greenhouses in Korea (지역별 특성화 온실의 실태 및 구조적 안전성)

  • 김문기;남상운;손정익;윤남규
    • Journal of Bio-Environment Control
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    • v.3 no.2
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    • pp.128-135
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    • 1994
  • Recently, regionally characterized greenhouses have been built every place around the country. These greenhouses insist of their higher performance by considering regional merits than the greenhouses without considering regional ones, but it is not clear. The purpose of this study was to make clear the characteristics of the regionally characterized greenhouses through the analyses of actual state and structural safety. The greenhouses were investigated and classified into wide span house, large pipe house, arched lattice house, wooden house, viniculture house, and domed pipe house. The frames of wide span house, arched truss house, viniculture house and domed pipe house were analyzed to be structurally stable under the design wind speeds and snow depths in recurrence intervals of 15 or 30 years, but large pipe house was a little unstable and required some reinforcements, and wooden house turned out to be unstable. In addition, foundations of all characterized greenhouses were stable against pull - out capacity under the design wind speeds in recurrence interval of 30 years.

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Variation of Photosynthetic Photon Flux in Commercial Plastic Greenhouses (상업용 플라스틱 온실의 광합성유효광량자속 변화)

  • Lee, Hyun-Woo;Kim, Young-Shik
    • Current Research on Agriculture and Life Sciences
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    • v.30 no.1
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    • pp.27-33
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    • 2012
  • This study was conducted to provide data necessary for clearing up the way to be able to improve covering and management method of covering material in commercial plastic greenhouse. The photosynthetic photon flux(PPF) in representative 4 different commercial tomato greenhouses was measured and analyzed. The variation trend of daily integral PPF was in agreement with that of the duration of sunshine. Each of daily integral PPF for 4 different experimental greenhouses was quite dissimilar, and was less than the amount of PPF necessary to grow tomato. October to November of beginning of winter was a good season to replace covering material in order to secure more PPF during insufficient winter season in greenhouse. The main inside factors to interrupt PPF incidence were thermal screen, inside covering material, condensation receiver in greenhouse. The single wide span greenhouse covered with PO film was superior to the other experimental greenhouses in the aspect of PPF transmittance.

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The Development of Wide-span Plastic Film Greenhouse for Strawberry Seedling Cultivation (딸기 육묘용 광폭 플라스틱 필름 온실 개발)

  • Man Kwon Choi;Myeong Whan Cho;Hyun Ho Shin;Ki Bum Kweon
    • Journal of Bio-Environment Control
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    • v.32 no.4
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    • pp.442-448
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    • 2023
  • This study aimed to develop an optimal greenhouse model for strawberry seedling during the summer high-temperature period based on the results of field surveys. We conducted a survey on the structure types of 46 strawberry seedling farms nationwide, including width, ridge height, eaves height, ventilation method, seedling bed width, and spacing. Based on the survey results, we derived the optimal greenhouse model by considering various factors. The greenhouse width was set at 14 meters to maximize the efficiency of seedling beds and overall space. The height was determined at 2 meters, taking into account ventilation during the summer season. To reduce stress on the supporting structure due to snow loads, we established a reinforcement installation angle of 50 degrees. We analyzed two different models that use support beams with dimensions of φ48.1×2.1t and φ59.9×3.2t, respectively, to ensure structural safety against meteorological disasters, considering regional design wind speeds and snow accumulation. We utilized these developed greenhouse model to conduct strawberry seedling experiments, resulting in a high survival rate of average 93.2%. These findings confirm the usefulness of the strawberry seedling greenhouse in improving the seedling environment and enhancing overall efficiency.