• Magazine of the Korean Society of Agricultural Engineers
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• v.55 no.4
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• pp.84-93
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• 2013

• Journal of Bio-Environment Control
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• v.22 no.1
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• pp.7-12
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• 2013

Environmental measurements in the many different types of horticultural farms were carried out to evaluate the ventilation performance for multi-span plastic greenhouses according to the eaves height, the number of spans, the existence of side wall vents and the position of roof vents. Hydroponic tomatoes were being cultivated in all experimental greenhouses, and ventilation rates of the greenhouses were analyzed by the heat balance method. It showed that the ventilation rate in the greenhouse with 4 m eaves height increased about 22% compared to the greenhouse with 2 m eaves height. The ventilation rate in the greenhouse with 9 spans decreased about 17% compared to the greenhouse with 5 spans. In the greenhouse with 9 spans, if there were no side wall vents, the ventilation rate showed about a third of the case that side wall vents were open. Overall, as the eaves height was higher and the number of spans was smaller in multi-span greenhouses, the natural ventilation performance was better. And the ventilation performance was best in the greenhouse which the eaves height was high and the position of roof vents was ridge, not gutter. Therefore, in order to maximize the natural ventilation performance, multi-span plastic greenhouses need to improve their structures such as that make the eaves height higher, place the roof vents on the ridge, install the side wall vents as much as possible, and the number of spans is limited to about 10 spans.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2002.11a
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• pp.306-315
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• 2002

본 연구는 지역별로 단동비닐하우스의 설치현황, 단면형상, 폭, 지붕높이, 측고, 측벽기울기, 골조재의 규격, 서까래간격, 가로대의 설치위치 및 개수, 내용년수 등을 현장조사를 통하여 비닐하우스의 구조실태를 파악하였다. 설치지역별에 따른 단동비닐하우스의 구조특성을 조사ㆍ분석한 본 연구결과는 관행적으로 시공되고 있는 소형비닐하우스의 구조표준화를 위한 기초자료로 활용할 수 있으며 매년 반복되고 있는 강풍과 폭설로 인한 소형비닐하우스의 피해를 줄일 수 있는 안전모델 개발의 기초자료로 활용할 수 있을 것으로 판단된다.

• 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)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 1998.05a
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• pp.89-93
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• 1998

농가보급형 비닐온실(1-2W형)은 농촌진흥청에서 '92년 4월에 폭 7m, 측고 2.7m, 동고 4.8m로 개발하여 각 시ㆍ군에 설계서를 배포하였으며 '95년 3월 자재일부와 동고의 높이를 수정하였고, 개량아치단동형(1-lS)과 '94년 6월에 개발된 한국형 유리온실과 함께 농민들이 가장 선호하는 시설형태 중 하나이다. (중략)

• Journal of Bio-Environment Control
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• v.11 no.1
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• pp.5-11
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• 2002

In this study, new development of natural ventilation window was accomplished to control environment of greenhouse with no use of farced ventilation during hot season. The ventilation effect of developed ventilation window was investigated in experimental greenhouse which was designed using side wall panel and folding type panel fur natural ventilation. Folding panel type ventilation window was designed to open upper part of the side wall and top of the roof using two hinges which are located bottom of the side wall and the roof panel to grab one side of each panels and guide the other side along with the guidance rail. Developed ventilation window has top ventilation part with maximum moving distance X=ι (1-cos$\theta$)=848.5 mm and side ventilation part with maximum moving distance Y=ι/2 $\times$sin$\theta$=1,184.4 mm at 45$^{\circ}$ of theoretical opening angle. It took 4.5 minutes to open roof vent fully and temperature at 1.2 and 0.8 m height decreased after 1 minute from starting opening and became equilibrium state maintaining 3-4$^{\circ}C$ difference after 2 minutes from complete opening. Air exchange rate was 15.2~39.3 h$^{-1}$ which was more than 10~15 h$^{-1}$ of continuous type and Venlo type greenhouse. The descent effect of temperature by ventilation windows was two times higher than Venlo type greenhouse.

• Journal of Bio-Environment Control
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• v.21 no.4
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• pp.428-436
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• 2012

This study aimed to develop the multi-span plastic greenhouse which is suitable for tomato cultivation and is safe against climatic disasters such as typhoon or heavy snow. The width and heights of eaves and ridge of newly developed tomato greenhouse are 7, 4.5 and 6.5 m, respectively. The width is the same but the eaves and ridge heights are 1.8 and 2 m higher than conventional 1-2 W greenhouses, respectively. Cross beam has been designed as a truss structure so it can sustain loads of tomato and equipment. Tomato greenhouse has been designed according to climatic disaster preventing design standard maintaining the high height. In other words, the material dimensions and interval of materials including column and rafter have been set to stand against $40m{\cdot}s^{-1}$ of wind and 40 cm of snow. Tomato greenhouse has been equipped with rack-pinion type roof vents which have been used in glass greenhouse in order to prevent excessive rise in air temperature. This vent type is different from that of 1-2 W type greenhouse which is made by rolling up and down the vinyl at upper part of column. Roof vents are installed at ridge, and thus external air inflow and natural ventilation are maximized. As the height increases, heating cost increase as well and, therefore, tomato greenhouse has been equipped with multi-layered thermal curtain, of which thermo-keeping is excellent, to prevent heat from escaping.

• Proceedings of the Korean Society of Organic Agriculture Conference
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• 2008.12a
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• pp.111-118
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• 2008

1. 고추 무농약재배 비가림 시설재배 효과 무농약 고추 노지 터널재배와 비가림 재배의 수량성을 검토하고, 관행 비가림 시설에 측고와 동고를 높이고 가로대를 보강하여 최소한의 투입으로 작물재배 환경을 개선으로 농작업에 편리성을 도모하고자 시험을 수행한 결과 비가림 시설재배가 노지 터널재배에 비하여 생육이 양호하고. 수량이 2배정도 많았다. 노지재배 고추는 강우로 인하여 탄저병이 40% 정도 발생되었으나, 비가림 시설재배는 탄저병과 역병이 전혀 발생되지 않았다. 2. 고추 비가림 시설 환경 개선 효과 구명 비가림 시설의 측과와 동고를 높이는 간단한 환경개선으로 여름철은 시설내 온도가 관행 비가림 시설보다 낮아지는 효과가 있었다. 또한 비가림 시설환경 개선에 의해서 "녹광" 풋고추의 생육은 증가되었으며, 홍고추 "조양" 품종도 같은 경향이었다. 고추의 수량은 풋고추 "녹광" 품종이 홍고추 "조양" 품종보다 수확량이 현저하게 많았고 처리간에는 비가림 시설의 환경을 개선한 시설이 관행 비가림 시설에 비하여 증수되었다. 그리고 비닐온실의 측고를 높인 결과 비닐 온실 내 측면으로 사람의 통행이 자유로워 작업환경 도도 개선되었다.

• Journal of Wetlands Research
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• v.11 no.2
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• pp.39-46
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• 2009

Garolim Bay is typically a semi-enclosed bay without a significant supply of freshwater and sediments from surrounding drainage area. The bay have a variety of subenvironments including deep tidal channels, tidal flats, sand dunes, islands, and inlet. Because environmental quality of bay strongly depends on the exchange of water over benthic subenvironments, it is necessary to analyze quantitatively exchange of water between sea and bay. Hydro-hypsography is the relative distribution of water-surface areas at different depths. The hydro-hypsographic curve in Garolim bay shows that the tidal flats occupy about 77 % of the bay surface. Hydraulic turn-over time (HTT) is 1.32 tidal cycles which indicate well-flushed bay. Hydro-hypsometric techniques will be useful for assessments of health of bays.

• Journal of Bio-Environment Control
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• v.22 no.4
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• pp.371-377
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• 2013

The government has been carrying out a project for supporting the rain shelter for hot pepper as part of measures stabilizing the demand and supply of hot pepper since 2012. However, the eaves height of single-span plastic greenhouses extensively used in farms is low, which are inappropriate for the rainproof cultivation of hot pepper. This study attempted to develop single-span plastic greenhouses which are structurally safe and have the dimensions suitable for the rainproof cultivation of hot pepper as well. The structure status of plastic greenhouses and restructuring wishes of 56 rainproof cultivation farms nationwide were investigated to set up the width and height of the plastic greenhouses. 53% of the plastic greenhouses currently in operation had a width of under 7 m and 64% of their eaves had a height of 1.5 m or less, which accounted for the highest rate. Mostly the width of 7.0 m was desired for the greenhouses and the height of 2.0 m for their eaves, so these values were chosen as the dimensions for the singlespan plastic greenhouses. After an analysis of their structural safety while changing the specifications of the rafter pipe in various ways, 5 kinds of models were suggested considering the frame ratio and installation costs. The 12-Pepper-1 model is a developed single-span plastic greenhouse for hot pepper in which a ${\emptyset}42.2{\times}2.1t$ rafter pipe is installed at an interval of 90cm and the models of 12-Pepper-2 through 5 are the other developed ones in which a ${\emptyset}31.8{\times}1.5t$ rafter pipe is installed at intervals of 60 cm, 70 cm, 80 cm and 90 cm, respectively. As a result of an analysis of economic feasibility of 12-Pepper-2 compared to 10-Single-3 in the notification of the Ministry for Food, Agriculture, Forestry and Fisheries, it turned out that there would be an increase in profits by about 1.2 million won based on one building of a greenhouse sized 672 $m^2$.