• Journal of Ginseng Research
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• v.15 no.1
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• pp.31-35
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• 1991

In order to know the optimum planting density under shading structures at different light intensity, We investigated the growth status, distribution of ginseng leaf area, correlation between planting density and root weight per plant and yield, correlation between leaf area index and root weight per plant and yield. According to the increase of planting density the leaf area per plant was decreased, but leaf area index (L.A.I) was increased. Ginseng leaf population at different lines under common straw shading were distributed mainly in frost lines but polyethylene net shading at 10fo light intensity were distributed equally in all lines. Optimum planting density in common straw shading at 5% light intensity was 55 plant per tan (90 cmX180 cm) and polyethylene net shading 81 10% light intensity was 60 plant per tan, in consideration of root weight and yield. Optimum leaf area index was 2.4 under common straw shading at 5% light intensity but was 2.7 under polyethylene net shading at 10% light intensity.

• Journal of the Korean Solar Energy Society
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• v.29 no.3
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• pp.28-36
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• 2009

The majority of fixed shading devices are installed in the exterior of a building in order to dissipate the heat absorbing from the sun and to prevent the direct sunlight. In designing external shading devices for windows, many requirements must be considered simultaneously; solar geometry, optimum energy performance, multi-purpose usage and design factors etc.. In order Lo satisfy these requirements, we suggests the folding shading device and its optimum design methodology. Also we analyzed the thermal performance using the IES_VE program according to various operating modes and compared with existing shading devices. The results show that proposed device reduce about $1.90{\sim}22.40%$ in cooling load and about $1.09{\sim}24.22%$ in heating load in comparison with existing ones.

• Horticultural Science & Technology
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• v.17 no.1
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• pp.29-32
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• 1999

This experiment was conducted to investigate the effect of different levels of shading (0, 35, 55, 75, 95% to incident sunlight) on the growth of Hedera rhombea Bean and Pachysandra terminalis Sieb. et Zucc. in order to determine optimum light intensity for ground cover plants. H. rhombea showed a upright growth type under 95% shading and P. terminalis was highest under 35% shading. Number of branches was not significantly affected by shading levels. Stem diameter and length were reduced under shading from 35% to 95%. Leaf growth was vigorous under 35% and 55% shade condition. Leaves became longer with decreasing light intensity, but shorter in 95% shading than control. There was a slight trend that total chlorophyll and chlorophyll a, b contents increased with decreasing light intensity, and so did chlorophyll a/b ratio. Fresh and dry weight of both plants were higher under 35, 55, and 75% shading than control and 95% shading. Specific leaf weight tended to decrease with reduction of light intensity. Thus, optimum light intensity for growth of them may be 35 and 55% shading of incident sunlight. In addition, it is possible to grow them under even 75% shading of incident sunlight.

• Horticultural Science & Technology
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• v.32 no.5
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• pp.584-589
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• 2014

Jeffersonia dubia is a spring-flowering perennial found in rich forests in Korea and Northern China and has potential as an ornamental or medicinal plant. However, illegal picking and land use change have decreased the number of populations and overall population size of this plant in its natural habitat. Although J. dubia has been reported to be a shade-preferring plant, no study has determined the optimum light intensity for its growth. The objectives of this work were to observe the effects of various shading levels on the physiological responses of J. dubia and to determine the proper shading level for cultivation. Treatments consisted of four shading levels (0%, 50%, 75%, and 95% shade) imposed using black mesh cloth. The number of leaves and dry weight increased with decreased shading. The shoot-to-root ratio increased with increased shading, mainly due to decreased root dry weight under shading. Plants showed low net $CO_2$ assimilation rates and $F_v/F_m$ values combined with low dry matter levels when grown under 0% shade (full sunlight). These results indicate that J. dubia plants experience excessive irradiance without shading, resulting in damage to the photosynthetic apparatus. By contrast, the net photosynthesis rate increased as the shading level increased. $F_v/F_m$, the potential efficiency of PSII, was 0.8 under 95% shade, indicating that J. dubia is well-adapted under heavy shading. However, the low dry matter of plants in the 95% shade treatment indicated that the low light intensity under 95% shade led to a decline in plant growth. Thus, moderate light (50% shading) is recommended for cultivating J. dubia without physiological defects.

• Journal of Korean Society of Forest Science
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• v.89 no.5
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• pp.591-597
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• 2000

This studies were carried out to investigate the optimum shading for seedling cultivation of Cornus controversa and C. walteri. The experiment was performed under five different shading scheme such as 100%, 50%, 30%, 10%, and 2% of the natural full sun light intensity for 7 months in the field condition. Two species showed the highest height growth under 50% of relative light intensity, and the highest diameter growth at root collar was observed both under 100% and 50% of relative light intensity. C. controversa seedlings grown under 50% of relative light intensity produced more total biomass than control seedlings, but root biomass was less in the seedlings under 50% of relative light intensity. In case of C. walteri, total biomass production of the seedlings under 50% of relative light intensity was lower than that of the seedlings under full sun light intensity, but leaves and shoot biomass was slightly high under 50% of relative light intensity. Great reductions of height growth and diameter growth at root collar, and biomass production were observed below 30% of relative light intensity in the both species. T/R ratio of the two species was highest under 30% of relative light intensity, and the chlorophyll content of the seedlings tended to be increased by reduction of relative light intensity.

• Korean Journal of Plant Resources
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• v.9 no.3
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• pp.254-260
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• 1996

The study was conducted to find out the ways of increasing fresh leaf yield under conditions of the optimum shading net treatment and planting densities of Aster glehni. Although the most effective shading net treatment to acclimatize the plant was 75% shading in 1993, as growing years were prolonged, effects of shading net treatment was not recognized. Ca contents in 75% shading net treatment was much higher than other shading net treatments. Shading effect tend to promote their growth and fresh leaf yield in 1993 even though 75% shading net treatment did not increase fresh leaf yield in 1994 and 1995. Planting density. $30\times20cm$. showed the effectiveness fresh leaf yield for 1994 and 1995 except for 1993.

• Journal of the Korean Solar Energy Society
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• v.35 no.2
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• pp.93-101
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• 2015

Zero energy building is a self sufficient building that minimizes energy consumption through passive elements such as insulation, high performance window system and installing of high efficiency HVAC system and uses renewable energy sources. The Korea Government has been strengthening the building energy efficiency standard and code for zero energy building. The building energy performance is determined by the performance of building envelope. Therefore it is important to optimize facade design such as insulation, window properties and shading, that affect the heating and cooling loads. In particular, shading devices are necessary to reduce the cooling load in summer season. Meanwhile, BIPV shading system functions as a renewable energy technology applied in solar control facade system to reduce cooling load and produce electricity simultaneously. Therefore, when installing the BIPV shading system, the length of shadings and angle that affect the electricity production must be considered. This study focused on the facade design applied with BIPV shading system for maximizing energy saving of the selected standard building. The impact of changing insulation on roof and walls, window properties and length of BIPV shading device on energy performance of the building were investigated. In conclusion, energy consumption and electricity production were analyzed based on building energy simulations using energyplus 8.1 building simulation program and jEPlus+EA optimization tool.

• Journal of The Korea Institute of Healthcare Architecture
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• v.18 no.3
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• pp.29-39
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• 2012

Window and shading designs have a great influence on energy consumption and daylighting in buildings. As far as energy is concerned, small window area is advantageous. But it is not good to the patient healing in hospital. So it is important to find out the optimum window shape which is favorable for both energy consumption and patient healing. In this study, annual energy consumption and daylight illumination levels were analyzed according to the window shapes and shading devices for a multi-beded patient room in hospitals. The simulations were conducted for 19 different cases by COMFEN 4.0 computer simulation program. The results of this paper are as follows. First, window to wall area ratio and shading devices have great influences on annual energy consumption. But it is a problem in that they decrease significantly daylight level in bed room. Second, considering the same energy consumption, reducing the width of window rather than the hight of window is desirable for the secure of daylight level. Third, increase of the number of horizontal shade is not desirable in south face of the building for the energy consumption and daylight level. Fourth, sun shade is not necessary in north face of the building for the energy consumption and daylight level.

• FLOWER RESEARCH JOURNAL
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• v.19 no.1
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• pp.37-41
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• 2011

This experiment was carried out to find an optimum shading level for the growth of root and shoot, and to find the effect of shading level after August on the induction and growth of inflorescence of Phalaenopsis hybrid. The shading levels were 50%, 60%, 70%, 80% and 90% of natural light($1200{\mu}molm^{-2}s^{-1})$. The $CO_2$ uptake, transpiration rate, carbohydrate content, fresh weight and dry weight of Phalaenopsis hybrid were higher at 50-60% level than the others. But, it was diminished when the shading level was increased from 70% to 90%. Inflorescence length, the number of inflorescence and flower per plant all increased under 50-60% shading level and the day needed for the flowering after treatment decreased. Especially, the induction of inflorescence was depressed and flowering is not occurred under 90% during experiment period. These results suggest that the optimal shading level for the growth of Phalaenopsis including inflorescence was founded to be 50-60% in the season of light intensity and amount of sunshine decrease after august.

• The Journal of the Acoustical Society of Korea
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• v.27 no.7
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• pp.350-356
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• 2008

In this paper, we propose shading functions to the appropriate focused beamforming for near-field target estimation. This near field shading functions are based on Chebychev and Manning windows. In order to obtain the optimum sensor weighting values with the help of the proposed shading technique, we assume that the sensor positions associated to the non-uniformly distributed array are precisely known. We calculate a series of sensor weighting values from the FFT operation of given shading functions in time domain. By applying the shading weights on the sensor array, we can see that the level of sidelobe becomes diminished and the performance of estimating range and azimuth gets improved. In addition, we propose a non-uniform structure in terms of frequency bands, which may minimize the attenuation of incoming signals.