• 한국산림과학회지
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• 제85권3호
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• pp.532-538
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• 1996

Indoor seed orchard의 가능성을 시험하기 위해 온실의 화분에서 자라는 낙엽송 접목묘와 야외에서 자라는 실생묘에 Gibberellins(GA4/7) 살포, 주입 및 몇가지 보조 처리를 사용하여 조기개화를 유도하였다. 온실의 화분에 지라는 접목묘에 대해서는 GA4/7 반복 살포 단독처리가 가장 효과적이었으나 보조 처리로서 사용된 root pruning은 상승효과를 보이 지 못했다. GA4/7 주입은 접목표의 치사를 초래하였기 때문에 유용한 방법이 아니었다. 10년생 실생묘를 이용한 야외실험에서는 GA4/7 살포와 보조처리로서 root pruning 또는 plastic mulching의 사용이 개화의 유도에 가장 효과적이었다.

• 국제학술발표논문집
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• The 10th International Conference on Construction Engineering and Project Management
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• pp.1316-1316
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• 2024

Greenhouses require various control systems to create an optimal environment, and from an architectural engineering perspective, the uniformity of the internal environment is crucial for crop growth. However, greenhouses are structurally exposed to external weather conditions, leading to a high probability of variations in temperature, humidity, CO2 levels, lighting, etc., across different zones within the greenhouse. Such non-uniformity can impact the growth rate, quality, and yield of crops, highlighting the necessity of maintaining a consistent environment within the greenhouse. To address this, experiments utilizing Computational Fluid Dynamics (CFD) simulations were conducted targeting greenhouses in Pocheon, South Korea, focusing on the central heating and cooling systems to propose an optimal design considering the uniformity of internal temperatures. Subsequently, validation was performed using measurements from temperature and humidity sensors within the greenhouses. The heating and cooling systems operate based on indoor temperatures, activating cooling when indoor temperatures exceed the set cooling temperature in summer and heating when temperatures fall below the set heating temperature in winter. A standard greenhouse model was set as case 1, and experiments were conducted by adjusting the position and spacing of the fabric ducts of the heating and cooling systems, resulting in six categorized cases. Variations in temperature and humidity distribution were observed among the cases, and quantitative analysis provided optimal positions and spacing for the fabric ducts. The results of this study can serve as foundational data for developing environmental control solutions for agricultural facilities.

• 한국농공학회논문집
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• 제53권6호
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• pp.145-152
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• 2011

In order to heat greenhouse nearby river channel, riverbank filtration water source heat pump was developed for getting plenty of heat flux from geothermal energy. Recharging well, thermal storage tank with separating insulation plate and filtering tank for eliminating iron, manganese were mainly developed for making the coefficient of performance (COP) of heat pump higher. Heating system using riverbank filtration water source heat pump was installed at a paprika greenhouse in the Jinju region where a single fold of vinyl cover and 2 layers of horizontal thermal curtain were installed as a part of temperature keeping and heat insulation with a greenhouse area of 3,185 $m^2$. 320,000 kcal/h was supplied for performing a site application tests. A greenhouse heating test was performed from Feb. 1, 2011 to Apr. 30, 2011. As the result of that, COPh of the heat pump was measured in the range of 4.0~4.5, while COPS of the system was represented as 2.9~3.3. COP measured of the heat pump was very good and well responded to indoor heating temperature of the environment control system of a greenhouse.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1998년도 학술발표회 발표논문집
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• pp.250-254
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• 1998

This paper shows how the environmental parameters(temperature, humidity) in the greenhouse are influenced by air movement produced by air circulation fans. When the fans were used, they could make indoor temperature and humidity homogenious, but there was no significant difference in the location and number of fans. When the fans were not used during the night time, there was no significant difference in the temperature and humidity, but the standard deviation was reduced by using the fans.

• Korean Chemical Engineering Research
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• 제60권4호
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• pp.606-612
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• 2022

실내 거주 시간이 늘어나면서 발생하는 CO₂를 인체에 무해한 농도인 1,000 ppmCO₂ 이하로 유지하기 위해 연구들이 활발히 진행 중이다. 본 연구에서는 저농도 CO₂흡착제로서 KOH와 K₂CO₃와 같은 알칼리성 첨가제를 상용 활성탄에 함침하여 사용하였다. 흡착된 CO₂ 양은열중량분석기(TGA)와 chamber(CO₂ IR analyzer)로평가하였다. 비표면적이 928.5 m²/g인 상용 활성탄(AC)은 KOH가 함침 된 KOH/AC(13.6 m²/g)와 K₂CO₃가 함침 된 K₂CO₃/AC(288.8 m²/g)보다 비표면적이 높았다. 챔버실험결과, AC는 CO₂를 거의 흡착하지 않았지만, KOH/AC와 K₂CO₃/AC는 각각 93.5 mg_CO2/g_sample 및 94.5 mg_CO2/g_sample 흡착하였다. 이것은 비표면적 및 미세기공의 부피에 의한 물리적인 흡착 영향보다 알칼리성 활성점의 증가가 CO₂ 흡착에 더 유리하게 작용한 것으로 판단된다. KOH/AC와 K₂CO₃/AC의 재생성능은 chamber test 결과 대조군(K₂CO₃/Al+Si supports)과 비교했을 때 안정적으로 흡착 성능을 유지하는 것으로 나타났다(3회 반복 실험). 또한, KOH/AC와 K₂CO₃/AC는열중량분석기의절대습도 1%H₂O를고려한조건에서 145.7 mg_CO2/g_sample및 150 mg_CO2/g_sample로 나타났다. 따라서 KOH 및 K₂CO₃ 등과 같은 알칼리 성분의 함침은 상용 활성탄의 안정적인 흡착 및 재생 후 흡착성능을 나타내어, 실내 이산화탄소 저감을 위한 흡착제 개발에 적용될 수 있을 것으로 판단된다.

• Journal of Biosystems Engineering
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• 제27권6호
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• pp.565-572
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• 2002

In order to control the root-zone temperature of greenhouse crops in the hydroponics at hot and cold season, heat pump system for cooling and heating was built and tested in this work. The system was air-to-water type and vapour compression type. The heating and cooling mode was selected by the four way valve. Capacity of the compressor was 3.75㎾ and heat transfer area of the evaporator and the condenser were 3.05㎡ and 0.6㎡, respectively. According to the performance test, it could supply heat of 42,360 to 64,372kJ/h depending on the water circulation rate of 600 to 1,500ℓ/h, respectively, when indoor air temperature was 10∼20$\^{C}$. COP of heat pump system was 3.0 to 4.0 in the heating mode. But, COP of the cooling mode was 1.3 to 2.1 at indoor temperature of 20∼35$\^{C}$. The feasibility test in the greenhouse the developed heating and cooling system was installed, showed that the heating cost of the developed system was only about 13% of that of the conventional heating system. The heating cost of the developed system was 367won/day(electric consumption 9.7㎾h/day), while that of the conventional system was 2,803won/day(oil consumption 7.7ℓ/day) at the same heating mode.

• Journal of Biosystems Engineering
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• 제23권6호
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• pp.599-606
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• 1998

This study was carried out to develop the control system with PLC and its operating software and to investigate its control ability of greenhouse environments. Two experimental greenhouses were controlled by PLC and ON/OFF controller, respectively. In greenhouse controlled by PLC, target values of air temperature, relative humidity and $CO_2$ concentration were automatically changed. In warm-water heating, the variation of air temperature was reduced to $\pm$ $0.6^{\circ}C$ by the method of proportional-integration(PI) control with an inverter. In ventilation, the variation of air temperature was reduced, since windows open and close with multistage by mutual relation formula among the target, indoor, and outdoor temperature. Relative humidity at daytime was maintained with range of 35% to 55% by PLC controlled fogger. $CO_2$ concentration was automatically controlled from 300 to 800 $\mu$molㆍ$mol^{-1}$ according to amount of solar radiation. The suppling amount and frequency of nutrient solution were controlled by total integrated solar radiation. Difference in the yield of cucumber in the greenhouse controlled by PLC and by ON/OFF controller was not significant at the 5% level.

• 교육녹색환경연구
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• 제10권1호
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• pp.34-41
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• 2011

Global environment is getting deteriorated at an alarming rate. Eco-school could be one of the effective solutions to project our environment and a good sample of architecture to economize in total energies, resources and greenhouse gases. In case of our country, the study of eco-school planning is not sufficient compared with other countries, so this paper would be a good study on the indoor environment of the classroom by surveying their opinions and ideas from the group of users in school facility. The result of this study shows that the proper installation of building equipment and nature ventilation system is necessary to provide delightful environment for the students and to save the energy. To ensure that we have adequate saving and protection it is necessary to change the existing appraisal standard.

• 교육시설
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• 제15권6호
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• pp.4-11
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• 2008

Global environment is getting deteriorated at an alarming rate. Eco-school could be one of the effective solutions to protect our environment and a good sample of architecture to economize in total energies, resources and greenhouse gases. In case of our country, the study of eco-school planning is not sufficient compared with other countries, so this paper would be a good study on the indoor environment of the classroom by surveying their opinions and ideas from the group of users in elementary school. The result of this study shows that the proper installation of building equipment and nature ventilation system is necessary to provide delightful environment for the students and to save the energy. To ensure that we have adequate saving and protection, it is necessary to change the existing appraisal standard.

• 농업과학연구
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• 제41권3호
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• pp.251-258
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• 2014

In order to set up the basic environmental control systems which the new concept greenhouses have to equip, greenhouse characteristics, environmental management and control systems in domestic glasshouses and plastic houses were investigated and analyzed comparatively. Survey results on the width, length, eaves height, and the number of spans etc. showed that glasshouses were bigger than plastic houses significantly. New concept greenhouses claim to be plastic houses, but it will be reasonable to follow the specifications of the glasshouse. Specifications to be applied to new concept greenhouses were proposed as follows; hot water heating systems, aluminum screens as the thermal curtain, evaporative cooling systems, roof vents on the ridge, circulation fans, $CO_2$ enrichment, hydroponic systems, and automatic irrigation control systems. Environmental measurement systems for the indoor and outdoor temperature, humidity, light, wind speed and indoor $CO_2$ concentration have to be fully equipped. The automatic control system has to be as a complex environmental control system, not a single item control system. Also, for stable dissemination, domestically producing complete greenhouse control system should be made as soon as possible.