• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.4
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• pp.307-316
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• 1994

To investigate the effect of light pretreatment on photosynthetic characteristics of leaf blade of rice, 2 varieties of japonica type and 2 varieties of tongil type were grown under 30% or 70% shading conditions from tillering stage to heading stage. Shading treatment of 70% at the heading stage produced low dry matter, and higher LAR and SLA compared with other combination of shading treatment and growing stage did. Photosynthetic activity was lower in order of 0%, 30% and 70% shading treatment under the low light intensity(5Klux) but significantly high in 30% shading treatment under the high light intensity (33Klux) at tillering stage. Photosynthetic activity under low(5Klux) and high(33Kluk) light intensity were higher in order of 70%, 30% and 0% shading treatment at heading stage. Respiration /photosynthesis ratio was lower in shading treatment than in control. CGR, RGR and NAR decreased in shading treatment. Shading treatment reduced the number of ripened grain per panicle and decreased the harvesting index.

• Korean Journal of Computational Design and Engineering
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• v.13 no.1
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• pp.1-7
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• 2008

Data compression becomes increasingly an important issue for reducing data storage spaces as well as transmis-sion time in network environments. In 3D geometric models, the normal vectors of faces or meshes take a major portion of the data so that the compression of the vectors, which involves the trade off between the distortion of the images and compression ratios, plays a key role in reducing the size of the models. So, raising the compression ratio when the normal vector is compressed and minimizing the visual distortion of shape model's shading after compression are important. According to the recent papers, normal vector compression is useful to heighten com-pression ratio and to improve memory efficiency. But, the study about distortion of shading when the normal vector is compressed is rare relatively. In this paper, new normal vector compression method which is clustering normal vectors and assigning Representative Normal Vector (RNV) to each cluster and using the angular deviation from actual normal vector is proposed. And, using this new method, Visually Undistinguishable Lossy Compression (VULC) algorithm which distortion of shape model's shading by angular deviation of normal vector cannot be identified visually has been developed. And, being applied to the complicated shape models, this algorithm gave a good effectiveness.

• KIEAE Journal
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• v.5 no.3
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• pp.3-9
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• 2005

Venetian blinds are used with windows to improve the uniformity ratio of illuminance and interior daylighting distribution under direct sunlit conditions. The main objective of Venetian blinds shading system is to obstruct direct sunlight and at the same time allow daylight to penetrate into the room. Venetian blinds would have greater effect on the interior daylighting condition under clear sky which has both skylight and sunlight than overcast sky which has only skylight. However, due to the lack of data, design and evaluation tools, it is difficult for architects to choose or install venetian blinds during the building design stages. The purpose of this study was to develop an analysis method for shading and daylighting effects of Venetian blinds using the RADIANCE program. The major variables related to the venetian blinds included blinds's slat angle and the ratio of slat width to window height, the radius slat of curvature and the building azimuth. In this study, a series of parametric physical mock-up model measurements and genblinds command in the RADIANCE simulations. The results of this study will provide building designers with the design data at early design stages.

• Asian Journal of Turfgrass Science
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• v.5 no.2
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• pp.95-114
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• 1991

This paper was designed to estimate the interaction of the first productivity, light conditions and to analyze the ecophysiological productivity, growth characteristics grown under various shading conditions in Zoysia japonica . The results summarized this experiment were as follows; 1.After transplanting the grass, increasing rate of leaf number and total leaf length was remarkahly high at the early growth stage in the control and the 30% shading plot. 2.The increasing rate of leaf area ratio (LA R) in all the experimental plot was remarkable high at the early growth stage after transplanting the grass. Especially, the control and 30% shading plot in compared with another plots, were remarkably high at rate of leaf area. 3.The length and the node number of rhizome in the control and 30% shading plot were also high and the difference was significantly large by the growth stage. 4.Chlorophyll content was very high at 36days after transplanting and then decreased. Increasing rate of shade resulted in its low content. The rate of chlorophyll a to b was decreased by in-creasing rate of shade. 5.The content of soluble sugar in the control and 30% shading plot was low at the early growth after transplanting and high at the late growth stage. Its content in the plot of 70% shading was remarkably low throughout the growth stage. 6.The increasing rate of standing plant in all the experimental plots was high at the early growth stage after transplanting. Increasing rate of shade was typically low through all the growth stage.

• Journal of Korean Living Environment System
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• v.24 no.6
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• pp.810-823
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• 2017

The envelope is important for sustainable building. Recent commercial buildings are causing thermal degradation and cooling load due to the increase of the area of the windows. Therefore, this research studied kinetic shading system which can improve energy saving and visual environment in summer. For that, this study proposed new shading system and shape considering the orientation of the building and the location of the sun. Based on this, this study analyzed the effectiveness on energy reduction and improvement of visual environment by applying the kinetic shading system proposed in this study. As the results of this study, energy reduction rate was 35% in the east, 22.9% in the south, and 30.7% in the west depending on the application location. Also, as the result of the illuminance analysis, it was found that the effect of achieving uniformity ratio of illumination was considerable.

• Journal of Korean Society of Forest Science
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• v.104 no.3
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• pp.390-396
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• 2015

This study was carried out in order to closely examine quality index by shading level of 2-year-old (1-1 seedling) container seedling of Daphniphyllum macropodum which is known as the species of having shade tolerance that is evergreen broad leaved tree in the warm temperate region. The shading treatment was regulated with the shading level of full sunlight, and 35%, 55%, 75%, 95% of full sunlight. As a result of surveying growth according to the shading level, both height and root collar diameter were surveyed to be the highest with 45.1 cm and 8.22 mm, respectively, under 75% of shading. The next was surveyed to be 43.2 cm & 8.05 mm and 42.5 cm & 7.98 mm, respectively, in order of 35% and 55% in shading. Leaf, shoot, root, and whole dry mass production were the highest under 75% of shading. The next was higher in leaf, stem, and whole dry mass production under 55% of shading. A root was higher under 35% of shading in the next. H/D ratio was the range of 5.29~5.35 under the 35~75% shading that showed the relatively high height and root collar diameter. T/R ratio was the lowest with 1.17 under 35% of shading. It was 0.41 under 95% of shading as for LWR, 0.24 under 75%-95% of shading as for SWR, and 0.46 under full sun and 35% shading as for RWR. QI was the highest with 3.74 under 75% of shading. As a result of surveying the whole experiment, it is concluded that the production of D. macropodum seedling is more effective under 75% shading

• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.598-608
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• 2011

The purpose of this study was to examine potential effects of shading and fertilizing treatment - two basic applicable factors in production of 1-year-old container seedling - on growth and seedling quality of Quercus myrsinaefolia, one of evergreen tree species in warm temperate zone of Korean. Every experimental process was conducted in a facility that consisted of compartments under the lighting control with full sunlight and shading (35%, 55% and 75% of full sunlight). Based on fertilizing treatment, this study made an experiment in 4 groups of container seedling: control (non-treated seedlings) and 1000, 2000, 3000 ppm group (3 groups with different concentrations of water-soluble fertilizer (N:P:K=19:19:19, v/v). Seedlings under 55% shading with 2000 ppm concentration showed the highest height (totaling 21.1 cm), and under 35% shading with 2000 ppm concentration showed the highest root collar diameter growth (totaling 3.96 mm) among others. All three fertilizing groups except control showed H/D ratio ranging from 4.27 to 5.26 regardless of fertilizer concentration under 35% and 55% shading where container seedlings showed a tendency toward excellent growth of height and root collar diameter. Overall, 2000 ppm group under 55% shading showed highest dry mass production of leaves (1,292 g) among others, while 2000 ppm group under 35% shading showed highest dry mass production of shoots and roots (0.592 g and 0.998 g, respectively) among others. Also, it was found that 2000 ppm group under 35% shading showed the highest dry mass production of whole seedling, which was followed by 2000 ppm group under 55% shading and 3000 ppm group under 35% shading, respectively. According to analysis on LWR of Quercus myrsinaefolia depending on shading and fertilizing treatment, it was found that 3000 ppm group under 75% shading showed highest LWR level among others, whereas every fertilized group showed lower RWR level than control without fertilizing regardless of shading levels. In general, all fertilized groups under 55% shading had relatively high quality index (QI), and 2000 ppm group under 35% shading had highest QI among others. Based on the findings of this study, it is concluded that shading level ranging from 35 to 55% and fertilizing concentration of 2,000 ppm are suitable for producing 1-year-old container seedlings of Quercus myrsinaefolia with excellent growth and high quality index.

• 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.

• Journal of the Korean Institute of Educational Facilities
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• v.15 no.2
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• pp.4-15
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• 2008

The purpose of this study was to evaluate the characteristics of daylighting environment in classroom of an school building due to the external shading devices such as fixed louvers, light shelves and exterior venetian blinds. In this study, we have made a field research with regard to the facade design in classroom of an school building. And we have made a classification of external shading devices considering the design parameters. Finally, through RADIANCE simulation, we have calculated the spatial distribution of illuminance, uniformity ratio of illuminance and daylight factors. The results of this study will provide the building designer with the basic daylighting performance data at early design stages.

• Korean Journal of Plant Resources
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• v.34 no.5
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• pp.462-469
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• 2021

Maesa japonica (Thunb.) Moritzi & Zoll. is a rare evergreen shrub that occurs in west Gotjawal, Jeju island, Korea. This study was conducted to investigate effects of an artificial shading on flowering and growth characteristics of M. japonica seedlings. The level of shading had been set to be 35%, 55% and 75% using shading net. The stage of flowering and flowering ratio, seedling height, the number of leaves and stems, leaf area were measured. Flowering timings were delayed by shading. The number of flowering seedlings per plot and inflorescences per seedling were the most in 55% shading level. Tendency of decreased seedling height with increased shading level was shown. The number of leaves and stems were the fewest values in 75% shading level. The increased biomass with decreased shading level was statistically significant. Aboveground and underground biomass were 2.1 and 1.7 times higher in shading 35% than in shading 75%, respectively. Meanwhile, all seedlings in non-shading plots were dead in winter. Such might be speculated as results of the light stress. As a result, we conclude that M. japonica vitally demands the shading for growth and the optimal shading levels for growth and flowering are 35% and 55%, respectively.