• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.5
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• pp.29-35
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• 2015

The optimal greenhouse scales for controlled tomato should be studied because the increase of oil price and labor costs following the shortage of workforce makes greenhouse cultivation hard to gain profits. The purpose of this study is to estimate optimal production scales by greenhouse types for controlled tomato. The translog cost function is estimated based on the production cost survey data. The results can be summarized as follows: First, the average production cost of controlled tomato per kg decreases as the production scale increases. Second, according to the tomatoes farm of standard farming income data of RDA, the minimum production scale is 23 ton. Third, the estimated output of single-span greenhouse considering production scale with minimum average cost is 345 ton and production cost per kg is 1,476 won. The corresponding figures of multi-span greenhouse are 415 ton and 936 won, respectively. The study results can be used as basic materials for efficient decision making of tomato farmhouses and novice farmers. Also, the study shows that multi-span greenhouse should be encouraged to be built, since it requires lower marginal cost than single greenhouse. The results of this paper will help increase the income of farmhouses and cut expenses for the coming years.

• Journal of The Korean Society of Agricultural Engineers
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• v.60 no.4
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• pp.105-111
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• 2018

Institutional inertia anti-disaster standard was presented mainly on the upper surface, it is necessary to improve to the soil type standard and uplift the resistance standard greenhouse that are vulnerable to strong winds. In this study, we carried out a field test using the load control method in order to evaluate the uplift resistance of continuous foundation of greenhouse with different depths of the rafters. Institutional inertia anti-disaster standard of greenhouse foundation did not protect the greenhouse structure from the damages caused by strong winds and heavy snow. Therefore, field tests for behavior characteristics of continuous greenhouse foundation were carried out to ensure stable facility cultivation. The field test condition was evaluated using different embedded depth as follows: 30cm, 40cm, 50cm and spacing 50cm, 60cm, 70 cm. As a result of the uplift resistance field tests using the load control method, the minimum uplift resistance was found to be over 90kg and uplift resistance displacement was 9.4mm. Uplift resistance of the continuous greenhouse foundation was in the range of 90-180 kg according to embedded depth and spacing. Using the test condition, there was no constant trend in the uplift resistance.

• Journal of Ginseng Research
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• v.29 no.4
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• pp.182-184
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• 2005

A new cultural practice for commercial production of American ginseng by organically grown in a shaded greenhouse under controlled environment conditions has been developed. This new procedure will shorten the dormant period and reduce the cultivation period from 4 years in conventionally grown ginseng to 2 years.

• Proceedings of the Korean Society of Crop Science Conference
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• 2001.05a
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• pp.134-135
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• 2001

• Journal of Biosystems Engineering
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• v.41 no.4
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• pp.328-336
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• 2016

Purpose: The heat culture areas of greenhouses have been continuously increasing. In the face of international oil price fluctuations, development of energy saving technologies is becoming essential. To save energy, auxiliary heat source and thermal insulation technologies are being developed, but they lack cost-efficiency. The present study was conducted to save energy by developing a conceptually new semi-basement type greenhouse. Methods: A semi-basement type greenhouse, was designed and constructed in the form of a three quarter greenhouse as a basic structure, which is an advantageous structure to inflow sunlight. To evaluate the performance of the developed greenhouse, a similar structured general greenhouse was installed as a control plot, and heating tests were conducted under the same crop growth conditions. Results: Although shadows appeared during the winter in the semi-basement type greenhouse due to the underground drop, the results of crop growth tests indicated that there were no differences in crop growth and development between the semi-basement type greenhouse and the control greenhouse, indicating that the shadows did not affect the crop up to the height of the crop growing point. The amount of fuel used for heating from January to March was almost the same between the two greenhouses for tests. The heating load coefficients of the experimental greenhouses were calculated as $3.1kcal/m^2{\cdot}^{\circ}C{\cdot}h$ for the semi-basement type greenhouse and $2.9kcal/m^2{\cdot}^{\circ}C{\cdot}h$ for the control greenhouse. Since the value is lower than the double layer PE (polyethylene) film greenhouse value of $3.5kcal/m^2{\cdot}^{\circ}C{\cdot}h$ from a previous study, Tthe semi-basement type greenhouse seemed to have energy saving effects. Conclusions: The semi-basement type greenhouse could be operated with the same fuel consumption as general greenhouses, even though its underground portion resulted in a larger volume, indicating positive effects on energy saving and space utilization. It was identified that the heat losses could be reduced by installing a thermal curtain of multi-layered materials for heat insulation inside the greenhouse for the cultivation of horticultural products by installing thermal curtain of multi-layered materials for heat insulation inside the greenhouse, it was identified that the heat losses could be reduced.

• Journal of Korean Society on Water Environment
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• v.22 no.4
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• pp.687-694
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• 2006

Dewatering sludge using inorganic chemicals with polymer has been evaded for reuse on account of the risks of high heavy metals contained and soil acidification. Composting feasibility of coagulation & dewatering sludges produced from livestock waste treatment plant was investigated. The results of analysis prove that dewatering sludge is valuable matter with suitable elements for composting if high quality ferric chloride ($FeCl_3$) is used for coagulation & dewatering process. In pot-cultivation of harvestes, using effects of dewatering sludge improved with lime treatment was very effective. The results of pot-cultivation proved that harms of crops according to different acid tolerances were not detected. But it was not applied to crops with weak acid tolerance or greenhouse for free from gas damage. Also, Further studies and monitorings are necessary to use sludges because results of pot-cultivation were generated differently by characteristics of soil, nutrient demand of plants, mature degree of sludge, consecutive cultivation and etc.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2002.04a
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• pp.48-50
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• 2002

오이의 원산지는 열대지방으로 생육 적온이 25-3$0^{\circ}C$ 정도로 매우 높다. 그러나 사계절이 뚜렷한 국내 기후 특성 상 생육적온 이하의 환경과 이상의 환경을 경험하게 된다. 시설오이는 온실에서 재배되기 때문에 계절에 따라 고온과 저온 스트레스를 받기 쉽다. 이 가운데 환기를 적극적으로 실시하는 여름철과 봄, 가을에는 밀폐된 공간의 특성상 열집적현상으로 환기가 제대로 이루어지지 않아 고온장해를 받는 경우가 많다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2002.04a
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• pp.60-61
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• 2002

시설호박은 재배작형이 매우 다양하여 시설억제, 촉성, 반촉성 및 시설조숙 재배 등으로 실시된다. 또한 재배 품종도 애호박, 풋호박 및 츄키니 호박 등 소비 경향에 따라 다양한 양상을 보인다. 시설호박의 암꽃분화는 저온단일에서 유기되지만 수확하기 위해서는 개화 당일 오전 8시 이전에 수분이 제대로 되어야 하고 일기불순, 질소과다, 고온관리, 밀식 및 정지불량 등은 낙화나 낙과의 원인이 된다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2002.04a
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• pp.57-59
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• 2002

봄철에 우리나라에 날아오는 황사는 발원지가 중국 고비 사막, 황하강 상류 및 타클라마칸 사막으로 알려져 있다. 그리고 최근에는 해마다 중국에서 여의도의 6배 정도의 면적이 사막화되어 피해가 심화되고 있고, 바람의 방향도 다양하여 피해 대상국도 대한민국과 일본과 같은 극동아시아 뿐만 아니라 중앙아시아까지도 확대되고 있다. 이 때문에 UN에서는 주변국들의 협조로 사막의 산림녹화 등에 힘쓰고 있으나 커다란 효과를 나타내지 못하고 있는 실정이다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2002.04a
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• pp.51-53
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• 2002

시설오이의 국내 재배면적은 2001년도에 5,412 ha 으로서 389천톤을 생산하였다. 재배작형은 시설억제, 촉성, 반촉성, 시설조숙 등 매우 다양하고, 재배작형과 지역적인 재배관습 그리고 소비경향에 따라 재배품종 또한 다양하다. 시설오이의 단보당 평균 수량은 7,184 kg 이지만, 이들 재배요인에 따라 단보당 수량이 지역별로 4배 정도로 차이가 많다. 즉 중부지방에서 무가온 시설조숙재배인 경우 과중이 120g 내외인 백다다기 오이를 4~5개월 정도 단기간 재배하기 때문에 수량이 단보당 3,500kg 정도이지만, 남부지방에서 7~10개월 정도 장기간 청장계 오이를 재배하는 경우에는 단보당수량이 12,000kg 이상을 넘는다. (중략)