• 한국생물환경조절학회:학술대회논문집
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• 한국생물환경조절학회 2003년도 추계학술대회 논문집
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• pp.183-186
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• 2003

• Journal of Biosystems Engineering
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• 제34권5호
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• pp.363-370
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• 2009

Hot air heater with light oil combustion is used as the most common heater for greenhouse heating in the winter season. Hot air heaters of 256,246 units have been supplied as main greenhouse heating equipment until 2008 and greenhouse heating cost has reached to 620 billions won in Korea. In order to improve the thermal efficiency of the hot air heater and to reduce the expenses for greenhouse heating, prototype hot air heater was manufactured and tested in this experiment. The heat exchanger of tested prototype hot air heater was circular and hexagonal pipe type and inline and stagger arrangement type. Capacity of the heating was 43,062 kJ/h and total heat transfer area of the heat exchanger was $10.728\;m^2$. According to the performance test, it could supply heat of 38,240 to 35,100 kJ/h depending on the fan motor speed of 1,740~1,220 rpm, respectively. Thermal efficiency of hot air heater was 87.0% to 80.8% in the same conditions. As a result, thermal efficiency of hot air heater with hexagonal pipe-stagger arrangement heat exchanger developed in this study was higher 10.2% than that of conventional hot air heater and heating energy saving rate of 14.3% increased.

• 생물환경조절학회지
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• 제25권4호
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• pp.270-276
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• 2016

This study analysed overall heat transfer coefficient, heat transmission, and rate of indoor air heating provided by water curtain in order to determine the heat transfer characteristic of double-layered greenhouse equipped with a water curtain system. The air temperatures between the inner and outer layers were determined by the water flow rate and inlet water temperature. Higher water flow rate and inlet water temperature resulted in the increased overall heat transfer coefficient between indoor greenhouse air and water curtain. However, it was found that with higher levels of water flow rate and inlet water temperature, indoor overall heat transfer coefficient was converged about $10W{\cdot}m^{-2}{\cdot}^oC^{-1}$. The low correlation of overall heat transfer coefficient between water curtain and air within double layers was likely because the combination of greenhouse shape, wind speed and outdoor air temperature as well as water curtain affected the heat transfer characteristics. As water flow rate and inlet water temperature increased, the heat transferred into the greenhouse by water curtain also tend to rise. However it was demonstrated that the rate of heat transmission from water curtain into greenhouse with water curtain system using underground water was accounted for 22% to 28% for total heat lost by water curtain. The results of this study which quantify heat transfer coefficient and net heat transfer from water curtain may be a good reference for economical design of water curtain system.

• 한국토양비료학회지
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• 제48권5호
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• pp.372-378
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• 2015

Growing crops under different soil textures may affect crop growth and yield because of soil N availability, soil N leaching, and plant N uptake. The objective of this study was to evaluate effects of three different soils (sandy loam, loam, and clay loam) on cucumber (Cucumis sativus L.) yield, nitrogen (N) use efficiency (NUE), and water use efficiency (WUE) by subsurface drip fertigation in the greenhouse. Three different soil textures are sandy loam, loam, and clay loam with 3 replications. The dimension of each lysimeter was $1.0m(W){\times}1.5m(L){\times}1.0m(H)$. Cucumber was transplanted on April $8^{th}$ and Aug $16^{th}$ in 2011. The subsurface drip line and tensiometer was installed at 30 and 20 cm soil depth, respectively. An irrigation with $100mg\;NL^{-1}$ concentration was automatically applied when the tensiometer reading was 10 kPa. Volumetric soil water content for cucumber cultivation was the highest in 30 cm soil depth regardless of soil texture and was lowered when soil depth was deeper. The volumetric soil water contents at soil depths of 10, 30, 50, and 70 cm were the highest at clay loam, followed by loam, and sandy loam. The growth of cucumber at the $50^{th}$ day after transplanting was the lowest at sandy loam. Cucumber fruit yields were similar for all three soil textures. The highest amount of water use at sandy loam was observed. Nitrogen and water use efficiencies for cucumber were higher for clay loam, followed by loam and sandy loam, while the amount of N leaching was the greatest under sandy loam, followed by loam, and clay loam. Overall, growing cucumber on either loam or clay loam is better than sandy loam if subsurface drip fertigation is used in the greenhouse.

• 생물환경조절학회지
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• 제15권1호
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• pp.47-52
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• 2006

This studies were carried out in summer season to increase high temperature tolerance using hydrogen peroxide treatments on cucumber in greenhouse. The water stress of cucumber in greenhouse by the hydrogen peroxide treatments showed as control>250 mM>500 mM treatments in order. The photosynthesis rate of cucumber at $30^{\circ}C$ did not show difference with each hydrogen peroxide treatment in temperature controlled greenhouse. However, the photosynthesis rate of cucumber in the control and hydrogen peroxide treatments at $40^{\circ}C$ was significantly different. The photosynthesis rate of cucumber in combined treatment with 1,000 $mg{\cdot}L^{-1}\;CO_2$ supply and hydrogen peroxide was also higher than control, however, there was no different of photosynthesis in 250 mM and 500 mM treatment. The value of $F_v/F_m$ and $F_m/F_o$ of chlorophyll fluorescent in 500 mM hydrogen peroxide treatment at $40^{\circ}C$ was highest. Also the activity of POD, the antioxidant enzyme, was higher with high hydrogen peroxide concentration than the other treatments. The high temperature limits for growth were $43^{\circ}C$ in the control, $44^{\circ}C$ in the 250 mM and $46^{\circ}C$ in the 500 mM according to analyze chlorophyll fluorescent $F_o$. The high temperature tolerance in cucumber increased approximately $3^{\circ}C$ by the hydrogen peroxide treatments under this experiment conditions.

• 식물병연구
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• 제12권2호
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• pp.75-80
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• 2006

2003 년부터 2005 년까지 장미 주요 재배단지를 중심으로 뿌리혹병 발생을 조사한 결과 전지역에서 발생이 확인되었으며, 주로 토양재배보다는 양액재배되는 장미에서 발생이 더 심하였다. 뿌리혹병에 감염된 장미는 주로 지제부에 발생이 많았으며, 뿌리에 발생하여 생육이 부진해지는 피해를 나타내었다. 저항성 품종 선발에서는 '리틀 실버' 등 10 품종만이 저항성 품종으로 검정되었을 뿐 대부분이 감수성이었다. 특히 '골든게이트', '리틀마블', '로사로제티' 등은 매우 감수성이 높았다.

• 한국응용곤충학회지
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• 제53권4호
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• pp.485-490
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• 2014

경기도 화성지역에서 시설재배 무화과를 대상으로 총채벌레의 발생현황과 피해특성을 조사하였다. 황색끈끈이트랩 및 피해과실에서 발생하는 총채벌레를 동정한 결과 파총채벌레(Thrips tabaci Lindeman), 꽃노랑총채벌레(Frankliniella occidentalis Pergande), 대만총채벌레(Frankliniella intonsa Trybom) 등 3종의 발생이 확인되었다. 이들 3종 중 파총채벌레의 밀도가 가장 높았으며, 다음은 꽃노랑총채벌레, 대만총채벌레 순으로 나타났다. 총채벌레에 의해 피해를 받은 과실은 비대생장과 착색이 정상적으로 이루어지지 않았고 표면이 거칠고 코르크화 되었다. 실체현미경을 이용하여 피해 받은 과실의 내부를 조사한 결과 피해부위에 회색곰팡이가 발생하였고, 총채벌레의 사체 및 탈피각이 관찰되었다. 무화과 주 수확기에 총채벌레에 의한 과실의 피해율은 7월이 18.2%로 가장 피해가 많이 나타났으며, 이후에는 8월(9.7%), 9월(2.9%), 10월(1.3%) 순으로 나타났다.

• 생물환경조절학회지
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• 제21권4호
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• pp.312-316
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• 2012

본 연구는 비닐하우스 피복재인 폴리오레핀(PO)계 필름의 효과를 구명하고자 관행의 피복필름(PE + EVA)과 비교하여 피복재별 물리적 특성과 상추와 오이의 생육 및 수량을 검토하였다. 인장강도, 인열강도 등 피복재의 물리적 특성은 일반필름보다 PO필름이 우수하였다. 400~700 nm의 광합성유효광의 투과율은 일반필름에 비해 PO필름이 4.1% 높았고, 전체 광선투과율(300~1,100 nm)도 PO필름이 4.3% 높았다. 하우스 내의 주간 평균기온은 일반필름보다 PO필름이 $1.5^{\circ}C$ 높았고, 야간 평균기온도 PO필름이 $0.8^{\circ}C$ 높게 유지되었다. 주야간 상대습도는 필름 간에 유의적 차이가 없었다. 엽록소 함량은 오이의 경우 필름 간 유의적 차이는 없었으나 일반필름에 비해 PO필름이 엽록소 a가 약간 높았으며, 상추는 PO필름이 일반필름보다 유의하게 높았다. 수확기 오이 생육에 있어서 초장, 엽면적, 생체중 및 건물중 모두 일반필름보다 PO필름을 피복한 하우스에서 크고 무거웠다. 수확한 오이의 과실 수량은 일반필름에 비해 PO필름이 14.0% 높았고, 상추 수량도 일반필름보다 PO필름이 13.6% 높았다.

• 생물환경조절학회지
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• 제31권1호
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• pp.52-59
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• 2022

시설재배 온실에서 병해충 방제를 위해 자율적으로 이동하면서 작물에 농약을 살포할 수 있는 무인 자동 농약 살포 시스템을 이용하여 방제처리를 실시하였다. 토마토, 딸기의 총채벌레(Frankliniella occidentalis)와 온실가루이(Trialeurodes vaporariorum) 해충에 대한 방제효과를 조사한 결과, 꽃노랑 총채벌레의 방제효과는 토마토에서 85.6%, 딸기에서 87.5%로 나타났고, 온실가루이는 각각 81.7%와 80.6%를 나타내었다. 또한 약제처리 방법에 따른 방제효과는 관행약제살포 처리구 81.7%, 무인 자율 약제 살포처리구 83.9%의 방제효과를 나타내었다(F=22.1, p < 0.001). 두 처리구간 방제효과 비교 시 현저한 유의성은 나타나지 않았으나 무인 자율 약제 살포처리에서 2.2% 높은 효과를 나타내었다. 한편, 약제 살포 시간을 비교한 결과, 무인 자동 약제 살포기는 살포시간이 5min/10a으로 관행 약제 살포시간 25-30min/10a 보다 25min 정도 적게 소요되었다. 이러한 결과는 발생최성기에 시설온실에서의 효율적인 해충 방제로 무인 자동 약제 살포방제법이 유용하게 사용될 수 있을 것으로 판단되었다.

• 농촌계획
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• 제24권3호
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• pp.33-42
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• 2018

The aim of our study was to provide a basic data for the development of a small greenhouse model suitable for urban farmers. The study analyzed installation inclination, positive and negative reasons for installation, location of installation, preferred crops in small greenhouses, plans for use of products, and expected effects by using small greenhouse. Positive opinion on small greenhouse installation was 80.4% of the survey respondents. The most positive reason for the installation of small greenhouses was fresh and safe food supply, and the negative reason was maintenance difficulties. The results obtained in our survey indicated that small greenhouses were more likely to be installed near the house, and urban farmers tended to grow organic leafy vegetables in soil. The expected benefits of small greenhouse operation were largely divided into 'benefit for the improvement of the quality of life' and 'benefit for economic profits', and expectation for the improvement of the quality of life was higher than economic benefit. As a result of the Likert 5-point scale analysis, 'benefit for the improvement of the quality of life' by using a small greenhouse was graded as high as 4.17~4.60. On the other hand, the 'benefit to economic profits' was rated as low as 3.51~4.14.