• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2003.04a
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• pp.140-145
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• 2003

폐쇄형 묘생산 시스템을에서 기내 배양된 감자 소식물체를 이용하여 플러그묘의 생산이 시도(Kim 등, 2002)된 이래 묘소질이 우수한 감자 플러그묘를 생산하기 위한 연구가 지속되고 있다(이 등, 2002, 2003). 묘소질은 정식 후 활착의 용이, 수량 증대 및 품질의 우수성을 제공하는 잠재력으로서, 초장, 절간장, 엽형, 엽색 등과 같은 외적 소질과 광합성속도, 엽록소함량, 근활력 등 내적 소질로 구분된다(Kim, 2002). (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2007.05a
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• pp.249-252
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• 2007

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2000.10b
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• pp.19-22
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• 2000

접목을 실시할 때 접수와 대목의 적정한 생육은 접목을 용이하게 할 뿐만 아니라 활착 후 접목묘의 묘소질 지속에도 커다란 영향을 미칠 수 있다. 자연광 조건에서 육묘를 실시하면 묘의 생육이 불균일하여 묘소질이 일정치 않게 된다. 그러므로 인공광을 이용한 폐쇄된 환경 조건에서 육묘가 바람직하나, 대목용 박에 대한 적정 광합성 유효광량자속 또는 광주기가 제시되지 않고 있다. 본 연구의 목적은 대목용 박의 초기 생육에 미치는 광합성 유효광량자속과 광주기의 영향을 구명하는 데 있다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2002.04a
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• pp.20-24
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• 2002

농산물은 기후와 시장동향에 따라 물량, 품질, 가격이 변동하고 산지에 따라 상품규격이나 품종이 다양하기 때문에 적기에 수출물량을 공급하고 지속적으로 확보하는 것이 어려운 문제로 대두되고 있다. 따라서 앞으로 농산물의 국제 경쟁력은 상품의 고품질화와 시장의 변화에 따른 상품의 안정적 공급에 달려 있다고 할 것이다. 연구결과에 의하면 작물이 안정적으로 생장하고 고품질의 수확물을 지속적으로 생산하기 위해서는 적정 일일적산 광합성유효광양자속을 균일하게 공급할수 있어야한다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2002.04a
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• pp.85-92
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• 2002

채소는 다른 작물에 비해 생육기간이 매우 짧기 때문에 환경의 영향을 많이 받는다. 특히 환경이 제어되는 시설에서 양액재배를 할 경우에는 생육이 왕성하므로 노지에 비해 재배기간을 단축시킬 수 있으며, 근권부 양액제어나 지상부 환경제어를 통해 고품질 채소를 생산할 수 있는 장점이 있다. 따라서 빠른 생육을 제어하거나 예측할 수 없어 수확적기를 놓치면 외관적 품질이 현저히 떨어지고 질적 품질도 저하하여 소비자의 기호에 맞추기 힘들게 된다. (중략)

• Journal of Ecology and Environment
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• v.30 no.1
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• pp.1-7
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• 2007

A model was developed to predict the effects of rising air temperature on net photosynthetic rate of Quercus mongolica stands at Mt. Paekcheok-san, Kangwon-do in South Korea. The PFD (Photon flux density) and air temperature were determined from weather data from the research site and the Daegwallyeong meteorological station and gas exchange or release responses of each tree component were measured. Using these data, we simulated the effects of increases in mean annual air temperatures above current conditions on annual $CO_2$ budget of Q. mongolica stands. If mean annual air temperature is increased by 0.5, 1.0, 1.5, 2.0, 2.5 or $3.0^{\circ}C$, annual net photosynthetic rate will be increased by 8.8, 12.8, 14.5, 12.6, 9.2 and 1.0 ton $CO_2\;ha^{-1}yr^{-1}$ respectively. Simulations indicate that changes in air temperature will have a major impact on gas exchange and release in Q. mongolica stands, resulting in a net increase in the rate of carbon fixation by standing crops.

• Journal of Environmental Science International
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• v.27 no.10
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• pp.821-829
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• 2018

This study was conducted to examine the influence of Light-Emitting Diode (LED) light quality in urban agricultural plant factories on the growth and development of Seolhyang strawberry daughter plants in order to improve the efficiency of daughter plant growth and urban agriculture. LED light quality by demonstrated that above-ground growth and development were greatest for daughter plant 2. Daughter plant 1 showed the next highest growth and development, followed by daughter plant 3. Among the different qualities of LED light, the stem was thickest and growth rate of leaves was highest for R + B III (LED quality: red 660 nm + blue 450 nm/photosynthetic photon flux density (PPFD): $241-243{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) and lowest for R (red $660nm/115-117{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$). Plant height, leaf width, petiole length, and the leaf growth rate were highest for W (white fluorescent lamp/$241-243{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) and lowest for R + B I (red 660nm+blue 450nm/$80-82{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$). For above-ground growth and development, as the plants surpassed the seedling age, mixed light (red + blue), rather than monochromatic light (red or blue), and higher PPFD values tended to increase development. Regarding the quality of the LED light, daughter plant 2 showed the highest chlorophyll content, followed by daughter plant 1, and daughter plant 3 showed the least chlorophyll content. When the wavelength was monochromatic, chlorophyll content increased, compared to that when PPFD values were increased. Mixed light vitality was highest in daughter plant 2, followed by 1, and 3, showed increased photosynthesis when PPFD values were high with mixed light, in contrast to the results observed for chlorophyll content.

• Journal of Bio-Environment Control
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• v.8 no.2
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• pp.108-114
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• 1999

This study was conducted to investigate the optimum environment for leaf lettuce (Lactuca sativa L. var. crispa) in a plant factory to increase mass-production efficiency of quality leaf lettuce. Transpiration rate and $CO_2$ assimilation rate were increased with increasing the photosynthetic photon flux density (PPFD). The highest fresh weight and dry weight were observed at the PPFD of 200 and 300 U moi $m^{-2}$ $s^{-l}$, respectively. The optimum aerial environment for the growth and quality of leaf lettuce in the plant factory was determined to be over 200 $\mu$mol $m^{-2}$ $s^{-1}$ for PPFB. Although the interaction between light intensity and nutrient level was not significant, the lettuce growth was the best under electrical conductivity (EC) of 1.8 mS $cm^{-1}$ / at high light intensity (250 $\mu$mol $m^{-2}$ $s^{-1}$ ) and EC of 2.4 mS cm-1 at low light level (150 $\mu$mol $m^{-2}$ $s^{-1}$ ) respectively.y.

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.3
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• pp.144-151
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• 2020

Agrivoltaic systems (AVS) is defined as combining farm-grown crops with photovoltaic panels (PV) installed several meters above the ground. Solar radiation (W/㎡), photosynthetic photon flux density (PPFD, µmol/㎡/s), air temperature (℃), vapor pressure (kPa), soil moisture (㎥/㎥), soil temperature (℃), wind direction (˚), and wind speed (m/s) were measured under the AVS in Boseong-gun during winter barley season. Data was collected by 5 minute interval. All data can download at Github site (https://github.com/chojaeil/AVS_Boseung). To gap-filling missing solar radiation data during about two weeks, the conversion coefficient from solar radiation to PPFD was estimated as 0.41. Further, according to the ratio of diffuse radiation to direct radiation, the maximum value among the twenty PPFD sensors under the AVS was related to the PPFD value of filed.

• Journal of Biosystems Engineering
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• v.26 no.4
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• pp.379-384
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• 2001

To enhance the smooth graft-taking of grafted seedlings, the excessive evapotranspiration from grafted seedlings just after grafting should be avoided. A measurement system of the evapotranspiration rate of grafted seedling under artificial lighting was set up to investigate the effect of physical environment on the evapotranspiration and graft-taking characteristics of grafted seedlings quantitatively. The evapotranspiration rate of grafted seedlings affected by relative humidity and light intensity were analyzed using the measurement system. The hypocotyl of watermelons (Citrullus vulgaris cv. Sweetdew, Hungnong Seed Co.) was slantly cut and then inserted into a hole on the stem of rootstock (Lagenaria siceraria cv. FR-King, Hungnong Seed Co.). Grafted seedlings were healed and joined for 5 days under cool-white fluorescent lamps (FL20SEX-d/18, Keumho Electric Co.) with photoperiod of 12h$.$d$\^$-1/ except dark period for one day after grafting in a closed graft-taking enhancement system developed by Kim(2000). The evapotranspiration rate and graft-taking of grafted seedling at air temperature of 23$\^{C}$ and air current speed of 0.1m$.$s$\^$-1/ was highly affected by relative humidity. But light intensity showed higher effect on the stem length of scion than relative humidity. In conclusion, it was suggested that relative humidity should be controlled at higher than 90% with photosynthetic photon flux of 50$\mu$mol$.$m$^2$$.$s$\^$-1/ to increase the survival of grafted seedlings and to produce healthy seedlings.