• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.4
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• pp.1-6
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• 2004

This study was carried out to investigate the effects of light intensities on the growth and net photosynthesis of Piper kauzura under different shading levels : 0％, 50％, 70％ and 90％ of sunlight. Mortality rate was lowest under a 70％ shading level but 0％ and 90％ shading levels were about 46％ and 53％ each respectively. Plant height was shorter and leaf size was smaller and yellowish under a 0％ shading level but increased when light intensity was decreased. However, under a 90％ shading level, growth of Piper kauzura was inferior to other treatments. Top fresh weight was about 11.24g under a 50％ shading level and about two times higher than that observed in about 6.6g under a 90％ shading level. Root fresh weight was about 7.7g under a 0％ shading level and was about two times higher than that showed in about 3.84g and 3.64g under 90％ and 70％ respectively. Total chlorophyll content and chlorophyll a/b rate were increased when light intensity was decreased. Net Photosynthesis achieved the highest under a 70％ shading level and maximum photosynthetic photon flux density was 150 molㆍm/sup -2/ㆍs/sup -1/. Therefore, growth of Piper kauzura was good under 50∼70％ shading, Meaning that it is an indoor plant that could be highly utilized.

• Journal of the Korean Solar Energy Society
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• v.28 no.2
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• pp.50-57
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• 2008

This study intends to evaluate the effect on indoor environment(annual thermal load, sunshine)by the application of the movable horizontal shading device on summer and winter season. For these purpose, we supposed the models which are composed of the several horizontal shading devices. Then we analyzed the simulation using the IES5.5.1 and Seoul weather data. The results of this study are as follows: 1) The proper length, angle of horizontal shading device is 2.1m, 28 degree, respectively. 2) The decreasing rate of the annual load of the Movable Horizontal Shading Model(MHSM) in comparison with the No Shading Model(NSM) & Conventional Horizontal Shading Model(CHSM) is 31.11%, 6.63% respectively. 3) The decrease of sunshine of the MHSM on summer season is effective the alleviation of visual displeasure. On the other hand, the increase of sunshine of the MHSM on winter season is effective the psychological comfort. Further study is to be required the sensitivity analysis on the various shading length for the realistic proper shading length.

• Korean Journal of Medicinal Crop Science
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• v.23 no.4
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• pp.271-276
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• 2015

This study was conducted to investigate the effect of shading degree and rooting media on the growth of Caragana sinica and Sedum middendorffianum after cutting. In C. sinica, the highest rooting rate was obtained in cuttings planted in horticultural soil (Sunshine Mix #1) and peat moss mixture (peat moss : perlite = 1 : 1, v/v) under one layer of 35% shading and in cuttings planted in kanumatsuchi soil mixture (kanumatsuchi soil : decomposition of granite = 1 : 1, v/v) under non-shading. Whereas, regardless of shading degree, most cuttings of S. middendorffianum rooted in both horticultural soil and peat moss mixture. Cuttings of C. sinica showed the highest root length, 10.4cm in kanumatsuchi soil mixture under one layer of 35% shading but the highest fresh and dry weight of roots in kanumatsuchi soil mixture under non-shading. In S. middendorffianum, the highest root length, fresh and dry weight of root were obtained in cuttings planted in horticultural soil under non-shading. With these results, we recommended that cuttings of C. sinica should be propagated in kanumatsuchi soil mixture under non-shading and cuttings of S. middendorffianum in horticultural soil under non-shading.

• Journal of the Korean Solar Energy Society
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• v.34 no.3
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• pp.12-20
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• 2014

There is no comprehensive consensus of the control patterns people op::rate shadings or the motivating factors that influence their decisions. Patterns of shading devices use can affect the energy consumption of buildings. Therefore, this study aims to analyze shading device usage patterns based on the physical factors that can affect occupants behavior. First, control patterns of indoor shading devices in apartment buildings were monitored by taking pictures. Next, frequency of shading device use together with their shading portions was analyzed based on two physical factors such as window orientation and floor level. The results showed that about 35% of the monitored apartment buildings utilized indoor shading devices. Also, the south-facing apartments were more dynamically used than their east-facing counterparts. On the contrary, there was no general trend in regards to the shading operation patterns.

• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.6
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• pp.73-76
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• 2004

This study was conducted to investigate the growth responses of Polystichum lepidocaulon as influenced by 4 different shadings(Control, 50%, 70%, 90%). Under 50 or 70% shading, plant height, stipe length, blade length, blade width, and number of spores increased compared with the other shadings, except the number of frond and shoots. The plants grown under control was shown as smaller with more yellowish green leaf color, and under 90% shading the growth was slightly inferior to those under the 50 or 70% shading. Fresh weight and segment area of frond was better in increased shade levels, but they decreased in under 90% shading. Dry weight and segment thickness decreased as shading increased. Chlorophyll contents increased in proportion to lowered light intensity. Thus, 50 or 70% shading of Polystichum lepidocaulon seemed to maintain the highest growth.

• Journal of Korea Multimedia Society
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• v.14 no.5
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• pp.691-702
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• 2011

Recently, several researchers have attempted to combine human visual perception and computer graphics. Cole et. al. suggest the study results in which line drawing algorithm in computer graphics characterize the properties of line drawing made by artists. The paper also evaluates CG line drawing algorithms depending on whether people recognize effectively specific 3D shape from the image made by those CG line drawing algorithms. However, human recognizes the shape of objects more effectively in image made by BRDF shading model than line drawing algorithm. It means that the shading factor is important to recognize shape with human perception. In this paper, we analyze the correlation between shading made by human artists and that made by CG shading algorithms. The study is to characterize the mathematical properties of artists' shading and CG shading. This type of analysis can guide the future development of new CG shading algorithm in computer graphics for the purpose of shape perception.

• Advances in Energy Research
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• v.5 no.4
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• pp.289-304
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• 2017

Large glazed surfaces and windows become common features in modern buildings. The spread of these features was influenced by the dependence of designers on mechanical and artificial systems to provide occupants with thermal and visual comfort. Countries with hot summer and cold winter conditions, like Jordan, require maximum shading from solar radiation in summer, and maximum exposure in winter to reduce cooling and heating loads respectively. The current research aims at designing optimized double-positioned external shading device systems that help to reduce energy consumption in buildings and provide thermal and visual comfort during both hot and cold seasons. Using energy plus, a whole building energy simulation program, and radiance, Lighting Simulation Tool, with DesignBuilder interface, a series of computer simulations for energy consumption and daylighting performance were conducted for offices with south, east, or west windows. The research was based on comparison to determine the best fit characteristics for two positions of adjustable horizontal louvers on south facade or vertical fins on east and west facades for summer and winter conditions. The adjustable shading systems can be applied for new or retrofitted office or housing buildings. The optimized shading devices for summer and winter positions helped to reduce the net annual energy consumption compared to a base case space with no shading device or with curtains and compared to fix shading devices.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.120-120
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• 2022

Agrivoltaic System (AVS) was introduced with the concept that it could generate electricity by using the extra light remain after crops use for photosynthesis in farm, which can earn additional income. However, crop yield was declined under the AVS condition due to the decrease in light energy. In the past, many researchers have been studied about crop states under shading conditions. However, the phenomenon of partial shading such as under the AVS is not well studied. In this study, to figure out the response of crop under the different light conditions, the electron transport rate (ETR) and non-photochemical quenching (NPQ) of rice was investigated using the chlorophyll fluorescence measurement. Also, physiological changes of crops under the shading conditions were investigated. The growth experiment under partial shading under AVS and overall shading which made of 35% shade cloth was conducted to understand the eco-physiological responses of rice to light in terms of the photosynthesis. Under the shading conditions, SPAD value and chlorophyll contents were higher, but the leaf thickness was lower than control. The overall shading condition show lower ETR than others during the growing season. In contrast, NPQ was higher than other treatments. This means the available light energy cannot contribute to photosynthesis under the shading condition.

• Horticultural Science & Technology
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• v.33 no.2
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• pp.227-232
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• 2015

This experiment was carried out to investigate the effects of shading materials (aluminum specific-shading screen and polypropylene non-woven fabric) and shading ratio (50% and 70%) on climatic changes, cut-flower quality, and yield of spray rose cultivars for export during high temperature periods. The daily cumulative solar radiations were higher with the aluminum specific-shading screen, especially with 50% shading compared to polypropylene non-woven fabric. Air temperature and root zone temperature within rockwool media greatly decreased with the aluminum specific-shading screen, but relative air humidity was not different among shading methods. Chlorophyll contents (SPAD values) were slightly higher with aluminum-specific shading screen than with polypropylene non-woven fabric, and were higher with 50% than with 70% aluminum specific-shading screen. Except for 'Lovely Lydia', marketable and exportable yields of all cultivars were higher with 50% than with 70% aluminum shading treatment. In addition, flowers talk length, stem diameter, number of node and 7ea-leaflet, and floret number tended to be better with aluminum specific-shading screen. Flower stalk length was higher with 70% than with 50% aluminum shading treatment. Chromaticity of petals slightly increased, and vase life was 0.5-2.5 days longer for each cultivar with aluminum specific-shading screen than with polypropylene non-woven fabric.

• KIEAE Journal
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• v.17 no.2
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• pp.29-34
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• 2017

Purpose: Recently, significant heat loss through the window takes place in buildings. Nevertheless, there exists little literature concerning the exterior horizontal shading devices and the design criteria are not clearly settled yet. Applying the exterior horizontal shading devices is more efficient as compared to the interior shading devices in that solar radiation can be directly blocked before passing through the window or the envelope. The purpose of this study is to reduce the internal load by designing the exterior horizontal shading devices and verify the degree of reduction in energy consumption. Method: This study aims to reduce energy consumption in cooling and heating through proposing proper length and shape of the exterior horizontal shading devices in public buildings. In the process, actual energy data and the Design Builder simulation program are utilized. In addition, economic aspect is considered to figure out the optimal length of the exterior horizontal shading devices that maximizes efficiency. Result: As a result, the proper length and shape of the exterior horizontal shading devices are provided as follows: 1) Energy consumption in cooling and heating is minimized when the exterior horizontal shading devices are designed as 0.5m*2. 2) Electricity bill is the lowest when the exterior horizontal shading devices are designed as 3.3m*2. The gap between maximum and minimum electricity bill is about 7.8~14%.