• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.243-249
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• 1998

This study was conducted for analyzing the influence of outside temperature upon shading effect of greenhouses by simulation. The simulation program was tested by comparing predicted values to measured values and applied the Korean standard wide span glasshouse. The shading effect according to the variation of outside temperature was different by shading method and rate. The increasing rate of inside temperature with different shading rate was nearly propotional to the increasing value of outside temperature. The outside shading effect was a little better than inside shading.

• KIEAE Journal
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• v.16 no.5
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• pp.65-71
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• 2016

Purpose : The solar shading device carries out roles in a reduction of the cooling load and an improvement of the thermal comfort of occupants by adjusting incident solar radiation. In addition, The shading device enhances the visual sensation comfort by controlling the optical properties. In order to improve building performance and comfort of occupancy, interests in application of the shading devices are getting increasing. This study investigated the application and effectiveness of the external shading device design using statistical analysis. The outcome of this paper could be utilized for the realization of status quo and for an estimation of effectiveness of the shading device Method : The period of data gathering was between 2003 and 2014 and total 459 cases of practical building project were investigated. Firstly, this study defined qualification of the shading devices; the shading device should have minimum protruding lengths of 150mm to outside and have the function of shading control. This paper investigated application rate of the shading device in real project, regional rate of application, annual change of application, materials and types. Result : The statistical analysis showed that the application rate of shading devices was 25.7% in total 459 building design projects. The application rate in central and southern region was 25.3% and 27.0% respectively. Meanwhile, Jeju region showed 22.2%, which was the lowest rate although this area needs more shading devices. The application number of the shading device was the smallest in 2007, but the rate gradually increased after that. The applications was the largest in 2014 due to growing interest of the shading devices in the building.

• Korean Journal of Medicinal Crop Science
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• v.28 no.2
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• pp.111-118
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• 2020

Background: Cnidium officinale is a medicinal crop sensitive to high temperature. It is necessary to develop environment control technology that can reduce environmental stresses such as high temperature. This study was conducted to develop technology for stable production of Cnidium officinale by reducing damage owing to high temperature by applying shading treatment of varying duration, and structure. Methods and Results: Black shading nets were used from May to September or November; shading structures such as pillar, flat roof, and tunnel type structures were installed. Environmental changes, rate of photosynthesis, and growth characteristics were investigated. The shading treatment reduced temperature by 3℃. The rate of photosynthesis and yield with shading treatment were higher by 134% and 127%, respectively, than those with full sunlight. The ratio of shading area ranged from 50% to 71% according to the type of shading structure. The effect of environmental control on growth varied depending on the type of shading structure. Conclusions: The shading treatment reduced damage owing to high temperature, shading rate of 55% - 75% was recorded between the period May - September, and the flat roof type shading structure was considered the most suitable among shading methods.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.1
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• pp.10-15
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• 1987

The experiment was designed to determine the proper shading rate and shading materials to decrease the excessive dried leaves during cure of burley tobacco. Five shading rates and seaven shading materials were applied on the pipe vinyl house from initial stage or yellow stage of cure. Temperature was lower and weight-loss of leaves delayed with shading from initial stage to browning stage of cure. Excessive dried leave were largely decreased as shading rate was increased to 70%. However, at shading rate more than 70%, its decreasing extent was fewer. Price per kg and physical properties improved considerably at shading rate of 50%. Shading materials alone could not completely prevent excessive dried leaves but it could decrease them. Orange, white and purple color vinyl among shading materials had so effects of shading as the black shading cloth during curing. However, white color vinyl didn't endure more than a few months due to sunshine. A difference of light quality in visible light was no significance on air curing.

• Asian Journal of Turfgrass Science
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• v.15 no.2
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• pp.77-86
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• 2001

The experiments were carried out to investigate effect of shading rare on variegata appearance and leaf growth of variegated liriope (Liriope platyphylla Wang et Tang variegata Hort.) The plant was grown under four different light intensities such as 0(natural light intensity), 25, 50 and 75% shading conditions. Leaf variegata appearance was better in the light than in the shade. Leaf showed good growth at 0, 25% shading treatment, average leaf width and area of yellow part were highest at 0% shading treatment. As increased shading rate, number of stomate per unit area decreased. Total chlorophyll of the whole leaf and green part were reduced by increasing shading rate, while yellow part showed oppositely. In the epidermis, cell size of 75% shading treatment showed larger than those of 0% shading treatment.

• Korean Journal of Plant Resources
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• v.11 no.1
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• pp.86-92
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• 1998

The photosynthetic rate (LPS)in the field was higher in the non-shading condition than in the shading. The fertilizer application was somewhat higher than non-fertilizer application. After humus application at 50% sading condition the growth and LPS increased with Ligularia fischeri. The maximum LPS at 80% shading was 22.3${\mu}{\textrm}{m}$mol/m/s with N-fertilizer application . Except Aster tataricus and Solidago virge-aurea. var. asiatic where the maximum LPS at non-shading and N-fertilizer application were 38.68 and 35.28${\mu}{\textrm}{m}$mol/m2/s. While the maximum LPS of Aster scaber was 30.01${\mu}{\textrm}{m}$mol/$m^2$/s at non-shading and non-fertilizer application. the growth rate was higher shading and fertilized conditions than non-shading and non-fertilized . The most effective shading condition was 50% , but leaf ration was highest in the 80% . But a. tataricus was favorable at non-shading and N-feritlized conditions.

• 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.

• 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 Forest and Environmental Science
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• v.36 no.1
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• pp.55-61
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• 2020

In this study, basic data with respect to the introduction of Hipphophae rhamnoides L. and its cultivation in Korea could be obtained. According to the size of the plug cell tray, Chinese origin's rate of seed germination was relatively high in 128 plug cell tray, and growth was vibrant in 50 plug cell tray. The germination and growth of Russian origin seeds showed that they were relatively effective in 50 plug cell tray and with respect to soil environment, TKS-2 soil with untreated shading relatively promoted both germination and growth for Chinese origin, the rate of germination was high in bed soil for horticulture and growth result was good in TKS-2 in the case of Russian origin. It was confirmed that the germination rate of Chinese origin H. rahmnoides L. was highest in untreated shading and the shoot growth was vibrant in 70% shading while the growth in roots was vibrant in the untreated shading. In the Russian origin, H. rhamnoides L. the germination rate in 30% and 70% shading was about 50% which was higher than that in the untreated shading and general growth was vibrant in 30% shading.

• Journal of The Korean Society of Grassland and Forage Science
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• v.7 no.3
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• pp.122-127
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• 1987

This experiment was carried out to investigate the effect of shading degrees (0:full sunlight, 25, 50 and 75%) on the crop growth rate (CGR), net assimilation rate (NAR) and photosynthetic activity of grasses for obtaining the basic data on the development, management and utilization of pasture in the forest. For the test, different artificial shading houses were established and pasture species used in this study were orchardgrass, timothy, perennial ryegrass and ladino clover. The experiment was performed at Livestock Experiment Station, Suwon, in 1984-'85. The results obtained are summarized as follows. 1. The highest CGR was obtained at 0% (full sunlight) and 25% of shading, followed by 50 and 75% of shading degrees, in that order. CGR of orchardgrass and perennial ryegrass were higher than those of timothy and ladino clover. 2. NAR was significantly decreased as the shading degrees increased. The highest NAR was observed at perennial ryegrass plot. 3. The photosynthetic activity during summer season was the highest at 25% of shading, followed by 50, 0 and 75% of shading degrees. While, the photosynthetic activity during fall season was the highest at 25% of shading, followed by 50, 0 and 75% of shading degrees, in that order. Those of orchardgrass and perennial ryegrass were remarkably higher than that of timothy. 4. A significant positive correlation was obtained in the relationship between CGR and NAR of main grasses, regardless of pasture species and investigated date.