• Proceedings of the Korean Society of Crop Science Conference
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• 1999.05a
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• pp.78-79
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• 1999

• Proceedings of the Korean Society of Crop Science Conference
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• 1997.10a
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• pp.96-97
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• 1997

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 2017.11a
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• pp.88-89
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• 2017

• Water Engineering Research
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• v.1 no.3
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• pp.187-197
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• 2000

This paper describes an adaptive quadtree-based 2DH wave-current interaction model which is able to predict wave breaking, shoaling, refraction, diffraction, wave-current interaction, set-up and set-down, mixing processes (turbulent diffusion), bottom frictional effects, and movement of the land-water interface at the shoreline. The wave period-and depth-averaged governing equations are discretised explictly by means of an Adams-Bashforth second-order finite difference technaique on adaptive hierarchical staggered quadtree grids. Grid adaptation is achieved through seeding points distributed according to flow criteria(e.g. local current gradients). Results are presented for nearshore circulation at a sinusoidal beach. Enrichment permits refined modelling of important localised flow features.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.1
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• pp.144-149
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• 1983

Experiments were conducted to develop a pelletization method of minute tobacco seeds for easy handling at seeding by hand or for mechanical seeding. Serpentine, zeolite, and talc were tested as coating materials and the resulting pills were compared in size uniformity, hardness, length of time needed for coating, percentage of pills containing a single seed, and speed of disintegration when submerged in water. Talc was the poorest and zeolite was good only in hardness. On the other hand serpentine was good in most characters above, except for brittleness. This defect, however, was overcome by double coating, first with serpentine and followed by zeolite. This new pelletizing method results in optimum hardness, uniform size, and high ratio of pellets containing one tobacco seed. When compared to bare tobacco seeds, the double-coated seeds did not differ in germination test.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.5
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• pp.110-120
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• 2009

The hipped roof on the research building, which was constructed 51.9m above sea level on a hillock by Korea National University of Education in June 1999, is composed of four inclined planes which are 12m in breadth, 8m in length and have a 30 degree gradient. For the roof vegetation, the yellow earth collected from around the building was laid on top. It was designed to supply the soil on the slope with water for a considerable period by making rainfall pool at the edges. In order to prevent the soil on the slope from being swept away, 31 sorts of grass seeds were imported from Germany and sown in the soil. At the present day, 10 years after the seeds began to sprout and inhabit the settled slope, 30 individual plant species were identified in the period between April 2008 and March 2009. Out of 31 species were seeded on the slanted, soiled roof, only 8 were still alive. It was confirmed that the Artemisia Princeps var, Chrysantheum, Prunella Vulgaris and Lespedeza Cuneata have been the major species inhabiting the east, west, south and north inclined planes respectively. The Phragmites Communis was inhabiting the edge of the roof where the water supply was adequate, while the Dianthus Barbatus was primarily inhabiting the south-east side of the roof. As a whole, 26 identifiable plants and 4 unidentified plants were observed on the inclined planes of the hipped roof. In consideration of the plant distribution on the slope, it was confirmed that the selection of seeds may have had an effect on the slope vegetation. As for the yellow earth laid on the roof, it was discovered that about 2~3cm thickness around the ridge was swept away, but the rest of the slope was in relatively good condition. Accordingly, it has been proven that vegetations can be applied to hipped roofs by using ordinary plants without any special structural measures.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.493-498
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• 1986

In order to evaluate the effect of various cultural methods developed during last 30 years on grain yield of wheat and barley and structure of plant stand for uptake of nutrient and water, solar energy use and com-petitive capacity with weed, 10 kinds of cultural practices were compared in the clayey upland soil. Row fertilization is more effective for uptake of N,P and K than rotary fertilization. Weed occurrence was deeply related with width of non-seeded area in the row and affected yield decrease. Winter injury was more serious in the cultural practices with thick plant community than in those with isolated individual plant. Root distribution was more remarkable in drill seeding or broadcasting than row seeding and had positively correlated with water consumption of barley.

• Journal of Korean Society on Water Environment
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• v.21 no.1
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• pp.59-65
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• 2005

A phosphate recovery system from artificial wastewater was developed using a completely mixed phosphorus crystallization reactor, in which powdered converter slag was used as a seeding crystal. In preliminary test, the optimal pH range for meta-stable hydroxyapatite crystallization for high phosphorus concentration was observed to be 6.0 to 7.0, which was different from the conventionally known pH range (8.0~9.5) for effective crystallization in relatively low phosphorus concentration less than 5 mg/L. The average phosphorus removal efficiency in a lab-scaled completely mixed crystallization system for artificial wastewater with about 100 mg/L of average $PO_4-P$ concentration was shown to be 60.9% for 40 days of lapsed time. XRD analysis exhibited that crystalline of hydroxyapatite formed on the surface of seed crystal, which was also observed in SEM analysis. In EDS mapping analysis, composition mole ratio (=Ca/P) of the crystalline was found to be 1.78, indicating the crystalline on the surface of seed crystal is likely to be hydroxyapatite. Particle size distribution analysis showed that average size of seed crystal increased from $28{\mu}m$ up to $50{\mu}m$, suggesting that phosphorus recycling from wastewater with high phosphorus concentration can be successfully obtained by using the phosphorus crystallization recovery system.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.6
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• pp.71-85
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• 2011

In Okdong coal mine abandoned area, every year large amount of mine wastes have been swept away due to heavy rains in summer. Because pH of coal-mine waste is in the early 4, plant naturally does not grow there due to unfavorable condition for growing plant. This study had an experiment to grow plant for 6 months using Mycorrhizae which can be adapted well in acid soil. As a result of Experiment, In the infected experiment pot, 90% of the plants survived but in case of uninfected experiment pot, only 25% were alive. From Growth Experiment, it appeared that average stem length increase (cm/month), average fresh weight increase ($g^{fw}/month$), average dry weight increase ($g^{dw}/month$) were increased by 60%, 21%, 31% respectively. Especially, Mycorrhizae plays an important role in providing nutrients and water when seeding are established. Mycorrhizae prevents death caused by lack of nutrients and water and helps growth and development of plant when seeding are established in the early stage. This study proved that Mycorrhizae is comparatively effective in plant growth and prevention of erosion in coal-mine abandoned area.

• Korean Journal of Plant Resources
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• v.11 no.1
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• pp.101-105
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• 1998

This study was carried out to find out the method of increasing seed germination rate of Dendropanax morbifera LEV. was drupaceous fruit. The length and width of ovarywas 7.8 to 10.7mm, 6.9 to 9.0mm, respectively, and the shape was elliptical. The ovary had 5 loculi with one speed per loculus , but one seed among 5 weeds was exalbuminous seed. The length and width of seed was 6.3 to 7.4mm, 2.0 to2.mm, respectively, and 1,000 seed weight was 14.3 to 18.0g. Seeding after stroring at $10^{\circ}C$ for 60 to 90 days was germinated to 87% . However, fall seeding directly after harvest was increased to 85% at hot-water treatement ($40^{\circ}C$) for 90 to 120 minute.