• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1995.10a
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• pp.82-84
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• 1995

현재 국내에는 여러 가지 개량된 형태의 온실이 보급되어 온실산업의 생산성이 상당히 증가하고 있다. 그러나 현재 널리 보급되어 있는 온실의 형태가 구조적 안전성, 환경조건 및 경제성 등의 측면에서 현실적으로 완전한 조건을 갖추었다고는 보기 어렵다. 따라서 이들 형태들에 대한 다양한 질적 개선을 통하여 국내 환경에 보다 적합한 형태로 개선 발전시킬 필요가 있을 것으로 판단된다. (중략)

• Journal of Bio-Environment Control
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• v.23 no.2
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• pp.148-157
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• 2014

The purpose of this study was to investigate greenhouse maintenance by farms by looking into greenhouses across the nation for greenhouse specification, disaster-resistance greenhouse construction, types and degree of damage due to natural disasters, pre-inspection in case of typhoon or heavy snow forecast, and fire-fighting facilities to prevent a fire. The findings were summarized as follows: as for greenhouse specification, the highest proportion of them were 90 m or longer both in single- and multi-span greenhouses in terms of length; 8 m or wider and 7.0~7.9 m in single- and multi-span greenhouses, respectively, in terms of width; 1.5~1.9 m and 2.0~2.9 m in single-and multi-span greenhouses, respectively, in terms of height; and 3.0~3.9 m and 6 m in single- and multi-span greenhouses, respectively, in terms of diameter. As for disaster-resistance greenhouses, farmers were reluctant to install such greenhouses. The low distribution of disaster-resistance greenhouses was attributed to the greenhouses built dependent on the old practice, the greenhouses already completed, and relatively high construction costs. As for damage by natural disasters, greenhouses were subject to more damage by typhoons than heavy snow. They mainly inspected the ceiling and side windows, entrances, and fixation bands for covering materials in case of typhoon forecast and the heating devices in case of heavy snow forecast. As for repair methods for greenhouse pipe corrosion, they preferred partial replacement to painting and did not use stiffeners for structures to prevent a natural disaster in most cases. As for the maintenance of greenhouse covering materials, most farmers inspected their sealing property but did not clean the coverings for light transmission. The destruction of structural materials can be prevented by eliminating greenhouse covering materials during a typhoon, but they were not able to do so because of the covering material replacement costs and the crops they were growing. The study also examined whether greenhouse farms had fire-fighting facilities to prevent a fire and found that they lacked the perception of greenhouse fire prevention to a great degree.

• Korean Journal of Agricultural Science
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• v.28 no.2
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• pp.99-107
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• 2001

It is difficult to install a ventilation window on the roof of single span greenhouses of arch shape. Investigation on the roof ventilation structures for those greenhouses was conducted. In small greenhouses with spans of 5 to 8 m, circular or chimney type ridge vents made of plastic were employed. In large greenhouses with spans of 12 to 18 m, even span roll-up ridge vents made of steel pipe were employed. The effect of roof ventilation was evaluated by comparative experiments between greenhouse installing ridge vents and having controlled side vents only. Roof ventilation contributed greatly to restraint of temperature rise and maintenance of uniform temperature distribution in greenhouses. And ventilation efficiency was analyzed by experiments on the opening and closing operation of the ridge and side vent. There were no temperature differences according to opening and closing sequence of ventilation window. But for greenhouse temperature control by ventilation, it is desirable to open side vents after ridge vents and to close ridge vents after side vents.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1999.11a
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• pp.174-178
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• 1999

현재 농가에 많이 보급되어 있는 플라스틱피복 파이프 온실은 폭설이나 돌풍을 비롯한 강풍하에 놓이게 되면, 피복재의 파손이나 구조적인 붕괴현상으로 인하여 온실내 재배작물이 치명적인 피해를 입는 경우가 발생하게 된다. 실예로 1994년 2월 12일의 폭설과 1995년 7월 23일의 태풍 등 최근 2년을 연속하여 폭풍이나 강풍으로 막대한 피해를 경험한 바 있으며, 1997년 11월 12일의 나주 돌풍, 1998년 1월 8일 서부 경남지역의 강풍을 동반한 폭설, 1999년 8월 3일에 상륙한 태풍 올가 등은 온실과 같은 경량구조물의 안전을 크게 위협하고 있다. (중략)

• Journal of Korean Association for Spatial Structures
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• v.5 no.4 s.18
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• pp.61-70
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• 2005

In paper the discrete optimum design program was developed using the continuous and discrete optimum algorithms based on the SUMT and genetic algorithms. In this paper, the objective function is the weight of structures and the constraints are limits state design limits method. The design variables are diameter and thick of steel pipe. Design examples are given to show the applicability of the optimum design using the continuous and discrete optimum algorithms based on the SUMT and genetic algorithms of this study.

• Journal of Bio-Environment Control
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• v.17 no.3
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• pp.197-203
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• 2008

This study was performed to check the structural safety of modified 1-2W Greenhouses to be utilized fur growing Paprika. This type of greenhouse was derived from being remodeled by enhancing the column height of conventional 1-2W type greenhouses. According to the results of structural analysis performed by SAP-2000, there was not significant change in critical snow depth in spite of increasing the column height of 1.2 m by welding. But the critical wind velocities were shown to be $26.0\sim4l.0m/s$, which were $3\sim18%$ lower wind velocities compared with those critical velocities estimated for typical type of 1-2W greenhouse. Under the wind loads, those maximum section forces such as shear force, axial force, and bending moment, together with the deformed frame shape of strained greenhouse, were almost similar in both typical type and modified type. Maximum bending moment of column was found at eave's height of column on windward side. Under the snow loads, those maximum section forces such as shear farce, axial force, and bending moment, together with the deformed frame shape of strained greenhouse, were almost similar in both typical type and modified type. Maximum section forces except axial force was found at eave's height of column. Maximum axial force was found at inner column. Soil bearing capacity together with the total foundation resistance against wind upheaval was found to be consistently safe enough to resist to both wind load and snow load.

• Journal of Bio-Environment Control
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• v.24 no.4
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• pp.308-316
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• 2015

This study was conducted to investigate the situation of ICT apply to plastic greenhouse, and the results be apply to design of new one. A CFD analysis were conducted to monitering the ventilation and energy saving of the single span greenhouse newly designed. The causes of delay to apply ICT to plastic greenhouse are the high cost for installation(24%), insufficiency of after services(19%), often disorder(16%), unskillful management of soft ware(15%), insufficient ICT efficiency(13%) and unsatisfying of income increase(12%). The parts of problem occurred in ICT plastic greenhouse are the structure, actuator, environmental control system and sensor(approximate 14%, respectively), remote control technique(13%), plant management technique(12%), energy saving technique(10%) and utilization of software(8%). In the condition of lateral window closed, the average wind speed changed to slow, but it was faster in the condition of leeward side window opened than in the condition of lee and winward side window opened. The air movement in the condition of lateral window closed occur by air moving fan not by out air. It is not affect the room temperature but effective the uniformity of room temperature. The average temperature of low height greenhouse was uniform than high height one. The average temperature in condition of 3rd curtain opened become same with outside temperature after 2 hours, but take more 5 hours in condition of 3rd curtain closed.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1999.07a
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• pp.91-96
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• 1999

농업구조개선의 일환으로 추진된 시설원예현대화사업으로 1990년의 25,450㏊이던 시설원예면적은 1992년부터 급격히 증가하여 1997년 말 47,264㏊로 늘어났다. 이 가운데 경질 및 유리 온실은 372㏊(0.2%)이고 플라스틱 피복온실이 46,892㏊ (99.8%)로 거의 대부분을 차지하고 있다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2003.04a
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• pp.48-51
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• 2003

아연도금 파이프 단동비닐하우스의 면적은 국내 원예시설면적의 80%를 차지하고 있으나, 시공의 용이성과 시공비의 저렴함으로 인하여 구조물로서의 공학적 설계에 대한 인식이 부족한 실정이다. 그리고, 온실형태는 지역농협이나 작목반 등에서 보유하고 있는 성형활대에 따라 결정이 되어지고 있다. 이러한 이유로 단동비닐하우스는 매년 태풍 및 폭설 등의 기상재해로 큰 피해를 입고 있는 실정이다. 따라서, 2001년말 농촌진흥청에서는 농가지도형 비닐하우스 모델을 10가지를 제안하였다. (중략)

• Journal of Bio-Environment Control
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• v.3 no.1
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• pp.72-81
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• 1994

최근, 원예시설의 자재의 규격화 및 국내상황에 적합한 원예시설의 설치를 위하여 구조안전기준 등을 포함한 일련의 체계적인 원예시설의 연구가 진행 중에 있고, 그 결과의 파생효과로써 최근 일부 온실의 시공시에 국내상화에 적합한 합리적인 구조설계가 정착되어 가고 있는 실정이다. 그러나 대부분의 온실설계에서 환경제어장치 정도의 언급 이외에는 환경설계 및 환경제어에 관련된 내용을 설계에 적용하는 예는 거의 없기 때문에 부가가치가 높은 생산시설의 설치에 따른 비효율적인 운용이 우려된다.(중략)