• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.2
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• pp.1-11
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• 2004

The purpose of this study was to determine usability as potted flowers and garden plants by controlled plant height using growth retardants. There was no significant difference on the dwarfing effect according to the degree of exposure the sun, but growth was well under full exposure to the sun. The plant height was decreased by application of Cycocel (CCC), Bonzi (paclobutrzol), Ancymidol, and Uniconazole compared to the control group, and treatment of Bonzi $5mg{\cdot}L^{-1}$ was most dwarfing effect for both full sun exposure or 70% controlled shading condition. No consistent different was found in stem diameter, leaf color change, the content of chlorophyll and anthocyanin when the concentration of plant growth retardants was altered. These factors were affected only by light intensity. In comparison to the results of the control group, leaf length, leaf width, plant width and petiole length were all reduced by the application of growth retardants.

• Journal of Environmental Science International
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• v.16 no.11
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• pp.1313-1318
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• 2007

Illicium anisatum was bred under four different light intensity. Those condition were full sunlight(PPFD $1600{\mu} mol\;m^{-2}s^{-1}$), 30% treatment(PPFD $400{\mu} mol\;m^{-2}s^{-1}$), 50% treatment(PPFD $250{\mu} mol\;m^{-2}s^{-1}$) and 70% treatment(PPFD $100{\mu} mol\;m^{-2}s^{-1}$), respectively. Chlorophyll a and b were increased according to decrease of light intensity. Thirty percent and 50% treatment had not significant different in chlorophyll a and b. Thirty percent treatment was shown the best photosynthetic activity through invested photosynthetic rate, intercellular $CO_2$ concentration and water use efficiency. Photosynthetic activity trend of 50% treatment was similar to 30% treatment. Seventy percent treatment was shown the best photosynthetic activity at low light intensity but that was decreased to lower value than 30% and 50% treatment under high intensity. Control, bred full sunlight, was shown the worst photosynthetic activity at measured all light intensity. That result could imply that was caused by photo-inhibition because of long term exposed of shade tolerant plant at high light intensity. Leaf characteristics had not significant different in leaf length, width and area but leaf dry weight had similar trend to photosynthetic activity.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.9
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• pp.635-640
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• 2010

This study is suggested tilt window type to be restrained solar radiation through vertical window type in buildings. The shading and aesthetical effect of buildings would be solved by installation of tilt window type. For investigate optimum an angle of tilt window and building azimuth in reference region, the distance of transmitted solar radiation is calculated. The results of calculation showed optimum an angle of tilt window is obtained $7^{\circ}$ that the distance of transmitted solar radiation is 20% of 1.5m of balcony width. In case of an tilt window angle of $7^{\circ}$, the optimum building azimuth is showed $SW15^{\circ}{\sim}SE15$.

• Korean Journal of Medicinal Crop Science
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• v.10 no.5
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• pp.379-383
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• 2002

The significant chemical components estimating the quality and growth characteristics in different parts of tea plants were compared and analyzed in the shoots of shading tea plants. The results are summarized as follows. The leaves length, leaves width and weigth of 100 buds in the leaves were increased with growing, while the leaf moisture was decreased. The contents of total nitrogen, caffeine, vitamin C and saponin in the leaves were decreased with growing, while those of total amino acid and chlorophyll were the highest in the 4th leaves and in 3rd leaves, respectively. The content of tannin ranged from 9.53% to 11.23%. The content of tannin at the 1st leaves was the highest as 11.24%, but that of the 4th leaves was the lowest as 9.53%. the content of fatty acid at the 2nd leaves was the highest as 3,594mg/100g, and that of the 5th leaves was the lowest as 2,782mg/100g. The contents of palmitic acid and stearic acid were the highest in the 5th leaves, but those of oleic acid, linoleic acid and linolenic acid were the highest at the 2nd leaves. In conclusion, the 5th leaves among tea shoots plucked after shading for 15 days could be used to manufacture powder green tea.

• The Journal of Natural Sciences
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• v.6 no.1
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• pp.55-64
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• 1993

Experiments were conducted to study the effect of auxins and cultural factors on rooting characteristics in offshoots cutting of Aloe vera. The result obtained were as follows;1. Short offshoots(15-20cm) with rhizome had more roots than that of the removed rhizome, while long offshoots(25-30cm) without rhizome had more roots and heavier root dry weight than short offshoots with rhizome. The highest rooting ability occured when IBA treated 500mg per liter in short offshoots with rhizome, whereas long offshoots without rhizome showed higher rooting ability at the level of 1,000mg/l of IBA and 200mg/I of NAA2. Among three kinds of anxin treated, both IBA and NAA showed better rooting ability than ethychlozate. Root number, root length and root dry weight were higher at 10 min. dipping treatment of IBA 500mg/I for short off-shoots without rhizome and 10 min. dipping treatment of IBA 1,000mg/l for long offshoots with rhizome. Rooting ability of long offshoots was higher than that of short offshoots.3. In addition to IBA 1,000mg/l, 7-day dryness under shading condition increased root number and dry weight of root in offshoots without rhizome. Control treatment lengthened root by increasing drying period under the shading condition.4. The plain soil with mamure had not only higher root dofferentiation but higher root growth of offshoots cutting than the artificial soil.5. Rooting ability in offshoots cutting had a tendency increasing with decrease in shading percentage to natural. Black color poly ethylene film mulching had better rooting ablility than transparency poly ethlene film mulching in offshoots cutting.

• Journal of Bio-Environment Control
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• v.14 no.2
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• pp.76-82
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• 2005

Evaporative cooling pad system is one of the main cooling methods in greenhouses and its efficiency is very high. However, it has some disadvantages such as greenhouse temperature distributions are not uniform and installation cost is expensive. In this study, a CFD simulation model f3r predicting the air temperature distribution in the fan and fad cooling greenhouse was developed. The model was calibrated and validated against experimental data and a good fit was obtained. The influence of different outside wind, fan and pad height, ventilation rate, shading, and greenhouse length, were then examined. In order to reduce the internal temperature gradients, it is desired that the prevail wind direction and the fan and pad heights are considered. The simulation indicates that high ventilation rates and shading contribute to reduce the temperature gradients in the fan and pad cooling greenhouse. In order to maintain the desired greenhouse temperature, the pad-to-fan distance should be restricted according to the design climate conditions, shading and ventilation rates. The developed CFD model can be a useful tool to evaluate and design the fan and pad systems in the greenhouses with various configurations.

• Journal of agriculture & life science
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• v.46 no.2
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• pp.19-25
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• 2012

This study is an analysis of the initial growth of Adenophora triphylla var. japonica, and the growth of their above- and underground parts by means of shading treatment in order to provide a basic data that can be used in growing A. triphylla var. japonica in mountainous area. As for the rate of sprouting by shading treatment, 25% treatment and control showed the earliest sprouting. The leaf unfolding had the same order as the rate of sprouting. The analysis of the characteristics of growth of above- and underground parts showed that the growth of aboveground parts are excellent in the 25% treatment. 25% treatment were shown to be the longest in the total length of roots and root projection area. Control were discovered to be the most prominent in root surface area, root diameter, and root volume. 75% and 25% treatment in distribution by root diameter showed 72.4% and 69.5% of very fine root(>0.5mm), respectively.

• Journal of Bio-Environment Control
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• v.32 no.3
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• pp.226-233
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• 2023

High solar radiation in summer season causes excessive respiration of crops and reduces photosynthesis. In addition, the rainy season, which mainly occurs in summer, causes a low light condition inside the greenhouse. A low light condition can reduce crop growth and yield. This study was conducted to evaluate the effect of shade and supplemental lighting on the growth and yield of cucumber during summer season. Cucumber grafted seedlings were transplanted in two plastic greenhouses on August 30, 2022. To reduce the light intensity inside the greenhouse, a 50% shading screen was installed in one greenhouse. Supplemental lighting was conducted from September 7, 2022 to October 20, 2022. HPS (high-pressure sodium lamp), W LED (white LED, red:green:blue = 5:3:2), and RB LED (combined red and blue LED, red:blue = 7:3) were used for supplemental lighting sources, and non-treated (nonsupplemental lighting) was as the control. The supplemental lighting was conducted before sunrise and after sunset for 2 hours with a photosynthetic photon flux density of 150 ± 20 µmol·m^-2·s^-1. The plant height, leaf length, leaf width, and SPAD value tended to increase in the shading group. RB LED increased stem diameter regardless of shading treatment. Fresh and dry weights of fruits were not significantly different in shading and supplemental lighting. Average fresh weight of fruits was not significantly different among supplemental lighting as the harvest date passed. In conclusion, in this study 50% shade treatment significantly improved the growth of cucumber during the summer season. In addition, the growth and fruit characteristics are better than the control without supplemental lighting. This study can be used as basic research data for applying supplemental lighting technology to cucumber cultivation.

• Journal of Bio-Environment Control
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• v.15 no.4
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• pp.406-411
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• 2006

New Guinea impatiens (Impatiens hawkeri) shows very sensitive responses to different light conditions. Due to these phenomena, testers of DUS (distinctness, uniformity and stability) for granting plant variety protection right often have problems distinguishing genetic or physiological differences. New Guinea impatiens 'Fishlimp 149' was grown under several light intensities in a rain-sheltered vinyl house to observe differences of plant growth and flowering. As compared with the control (avg. $1,010{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$), treatments of shade-1 (avg. $599{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) and shade-2 (avg. $88{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) showed increased plant height, plant width, leaf size and pedicel length. On the contrary, these growth parameters decreased in shade-3 (avg. $30{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) with the lowest light intensity. Shade-1 treatment enhanced flower characteristics such as flower diameter, upper petal width, side petal width and lower petal length. However, these characteristics were suppressed by lower light intensities than that in shade-1. Anthocyanin contents of shoot, leaf and pedicel decreased with increasing shading, but that of flower petal was the greatest of the shade-1 treatment. Shade-1 treatment showed the greatest Hunter a value analyzed by a colorimeter, and L and b values increased with increasing shading. Shade-1 treatment seemed to be provided the most proper light condition for DUS test of New Guinea impatiens. Additionally, anthocyanin accumulation on New Guinea impatiens during DUS test was due to not genetic differences but physiological phenomenon.

• Journal of Ginseng Research
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• v.8 no.1
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• pp.65-74
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• 1984

This experiment was carried out to study the effects of light intensity and soil water regimes on the growth of ginseng seedling. The results were as follows: 1. The maximum light intensity and optimum temperature in 1,le photosynthesis of ginseng seedling were 10,000 lux and 23 $^{\circ}C$. Respiration rate was increased at high temperature. 2. Air and soil temperature under the shading were increased as the increase of light intensity but soil water contents were decreased as the increase of light intensity, whereas air and soil temperature were decreased as the increase of precipitation under the shade b5: soil water contents were increased as the increase of precipitation under the shade. 3. The higher the transmittance of the shade, the greater the specific leaf weight (S.L.W.) and stomatal density. In contrast, however, the contents of total chlorophyll, chlorophyll a and b, and stomatal length was decreased. There was no any significant difference light intensity of the a/b ratio of chlorophyll. 4. The highest photosynthesis was occurred in ginseng leaves grown under the shade 5% L.T.R. and net photosynthesis rates increased with increasing soil water contents. 5. Optimum condition for usable seedling yield were 5% L.T.R. and 3.3% precipitation under the shade. Useless seedling increased with increasing precipitation under the shade.