• Journal of Ocean Engineering and Technology
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• v.22 no.5
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• pp.44-51
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• 2008

The planning and design of coastal structures against wave attack is required to accurately predict wave transformation, wave run-up, and fluid. particlevelocities an a slope. On tire other hand, in tire swash and surf zones of a natural beach, where coastal erosion and accretion occur at tire land-sea boundary, hydrodynamic analysis is essential. In this study, a RBREAK2 numerical model was created based on the nonlinear shallow water equation and laboratory measurements were carried out in terms of tire free surface elevations and velocities for tire cases of regular and irregular waves on 1 : 10 and 1 : 5 impermeable slopes. The data were used to evaluate tire applicability and limitations of tire RBREAK2 numerical model. The numerical mode1 could predict tire cross-shore variation of the wave profile reasonably well, but showed more accurate results for slopes that were steeper than 1 : 10. Except near tire wave crest, tire computed depth averaged velocities could represent tire measured profile below tire trough level fairly well.

• Korean Journal of Environment and Ecology
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• v.11 no.3
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• pp.270-276
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• 1997

The purpose of this study was to investigate the number of climbing plant species habitated in South Korea. Relationships between their distribution and environmental factors were surveyed. Research sites for vertical distribution were Mt.S rak, Mt.Kwangkyo, Mt. Eoudap and Mt. Chiri. The results of this study are as follows: The number of climbing plants habitated in South Korea was 267 species, 95 genera, 41 families. According as latitude lower, the number of climbing plant species increased. And most areas of Korean peninsula except for alpine regions and the northern part of North Korea seemed to be suited for the growth of climbing plants. The number of climbing plant species decreased with its altitude. And it is confirmed that their distributions were limited to the below of 1,500m sea level which was applicable to the area of Kira's warmth index above 45. The species of climbing plants changed with its plant community although at same altitude. The number of climbing plant species was different from the face of slope, and the species diversity became lower at south slope than that of north slope.

• Journal of the Korean GEO-environmental Society
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• v.2 no.2
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• pp.41-50
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• 2001

In this study, for the stability analysis of marine embankment, the slope stability analysis and possibility of lateral movement with the marine embankment in ${\bigcirc}{\bigcirc}$harbor were carried out. In order to simulate the practical site condition, the expected maximum sea water level and maximum embankment height were assumed for these analyses. For the evaluation of soil properties, field test, laboratory test, and especially chemical composition analysis were performed for the this analysis. Based on these test results, the soil parameters were determined by applying ground improvement concept under columnar stabilized ground condition and also the effect of staged backfilling was considered under the dredged ground condition. For the optimal design, the stability analyses of embankment with changed height and unchanged height were performed under unimproved soil condition. The result showed that both cases were unstable not only with slope stability but also with lateral movement. Therefore, Deep Mortar Piling was applied for stability analysis and this result was safe. As the conclusion, the deep mortar piling method was suggested as reinforced foundation design for this site.

• The Korean Journal of Ecology
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• v.13 no.4
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• pp.321-329
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• 1990

An investigation was performed to elucidate wave character of the timber line on the middle slope of the west side of Paektusan. The Betula ermanii forest, which composes the timber line on about 2, 060m elevation of sea level, is the pure community of B. ermanii. Diffraction pattern of wave distribution of B. eramnii due to boundary condition of alpine temperature gradient was found out on the timber line. Interference patterns of waves of B. ermanii communities produced by environment conditions such as soil layers, whids, snow and relief were shown on a specific area. These facts indicate that the B. ermanii individuals have wave and particle duality, the complementarity principle.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1713-1716
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• 2003

Casing Oscillator is a construction machine that used to insert casings which is based on construction of a building or bridge into the ground. The purpose of using casing supports a pile or in case when heavy loads and moments happens. It is very important that the casings are retaining perpendicular to sea level regardless of the slope of the ground. So it requires that Casing Oscillator keep horizontality. But, it was useless a horizontal control without another heavy equipment. Tornado is a type of Casing Oscillator to advance. It controls horizontality with 4 cylinders. Those cylinders controlled by high-speed solenoid valves. This paper represents horizontal control of the Tornado using Kinematics. First. the horizontal control simulated by AMESim, which is simulation tool. then it compared with experimental results.

• Journal of Environmental Science International
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• v.12 no.1
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• pp.15-22
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• 2003

Fifteen major naturally populated habitats around the Mt. Halla, Jeju province for wild Cornus kousa are mostly located on the southeast side of the mountains at 850-1,550m in altitude at sea level and are in half sunney areas. More than 40.0% of the naturally populated area of Cornus kousa are edge of forest areas and 53.3% populate on the steep slope of the mountain in 0-5℃. The direction of the slop for about 40.0% of total populated areas is southeast. In the naturally populated areas, total of 64 taxa dividing into 42 families, 59 genera 56 species and 8 varieties have been shown, mostly Hydrangea petiolaris, Rubus oldhamii, Ilex crenata, Sasa quelpaertensis, Ligustrum obtusifolium. It is suggested that these areas are secondary forest in a typical deciduous forest in Mt. Halla where the second transition had been progressed after forest damage or environmental stress. The index of species diversity of plant groups in these areas is 1.286-4.238 based on the Shannon-Wiener's method.

• Plant Resources
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• v.4 no.1
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• pp.59-64
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• 2001

This study was conducted to clarify the floristic composition and to investigate the landscape structure of habitats of Aconitum pseudo-leave var. erectum. A. pseudo-leave is designated an endemic plant in Korea. Floristic compositions of habitats were mainly composed of Quercus mongolica community. Other elements in this composition were Weigela subsessilis, Corylus sieboldiana and Cornus contioversa. Landscape ecological structure of habitats were defined by soils of mesic, loamy skeletal, slope of more than 60$^{\circ}$, sixty percent of woody coverage at 460-520m above the sea level and 25m away from drainage. Distribution patterns of A. pseudo-leave var. erectum plants in Taejon were presented on the 1km X 1km grid map.

• Journal of the Mineralogical Society of Korea
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• v.22 no.2
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• pp.115-127
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• 2009

Mineral quantification was performed on sediments of the Ulleung basin by X-ray powder diffraction and the computer software based on Rietveld quantification method. The sediments are dominated by amorphous opal-A with quartz, feldspars, micas, clays, calcite, and pyrite. The opal-A shows iterative variation in abundance with increasing burial depth. In addition, the relative abundance of opal-A is coincident with abundance of organic carbon contents, indicating that the Ulleung sediment consists mostly of amorphous silica derived from organism in the pelagic environment. Upward increase in the abundance of opal-A is markedly shown in the cores located in the slope region. On the other hand, there is a distinct tendency that the abundance of calcite is inversely proportional to that of opal-A. This indicates that the abundance of opal-A increases during the rise of sea level. Also, the fall of sea level lowers the abundance of opal-A.

• Journal of The Geomorphological Association of Korea
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• v.25 no.1
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• pp.1-17
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• 2018

The characteristics and burial ages of sand sediments on the Jiduri coast in Daechung-myeon, Ongjin-gun, Incheon were investigated. Daecheong Island is the area where the characteristics of the rocky coast and sand coast are shown. Various studies have been conducted on the Okjukdong sand dune that appears in the north of the island. However, there has been no study on the sandy sedimentary topography of the Jiduri and Moraewul area in the south. The sandy sedimentary terrain of Jiduri is divided into sandy beaches, sand dunes and sand deposits along the slope including climbing dune. Overall, the depth of sandy sediments in Jiduri is not deep. The characteristics of sandy sediments and burial ages were investigated at an elevation of about 23 m above sea level at the back of Jiduli Beach and 46 m above sea level at the ridge line between Jiduri and Moraewol. From the Jiduri coast to the hillside behind, the average grain size decreases and the sorting becomes better as it moves from the intertidal zone to the beach and the foredune. This indicates the selective sand transport by the wind and can be judged by the terrain formed under the current sedimentation environment. The average grain size at the upper part of the section of JD-1 (elevation of about 23m MSL) was $1.6918{\varphi}$ of medium sand. The sorting was $0.4584{\varphi}$, skewness was -1.0491 and kurtosis was -1.2411, respectively. Particularly, the average particle size of the crosssection issomewhat uniform, but the color of the constituent material changes from brown to black. In the case of JD-2 (about 46 m MSL), the mean grain size of the section was $1.7943{\varphi}$, the sorting was 0.4931, the skewness was -1.1163, and the kurtosis was 1.2133. On the other hand, the brown and black layers of JD-1 exhibited a burial age of $0.1{\pm}0.0ka$ and the JD-2 had a burial age of $0.7{\pm}0.0ka$.

• Economic and Environmental Geology
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• v.36 no.6
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• pp.527-536
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• 2003

The Dokdo volcano in the south-central part of the East Sea is classified into 8 rock units. The units and sequence suggest that the Dok Island forms a small stratovolcano constructed from at least 3 times eruption cycles above the sea level and proceeded with transformation of a few different eruption styles during each cycle. Reconstruction of the volcanic form, from the geologic structures and spatial lithofacies changes, suggests that the island is remnants of the southwestern caldera rim of the stratovolcano whose central part lies several hundred meters to the northeast. The subaqueous volcano shows abig guyot, which looks like a shield volcano, that represents gentle slope at 90-175 m deep and relatively steep one in 200∼2,000m, and 25∼30km wise base on sea floor. Therefore the total Dokdo volcano represents a multiple volcano that stratovolcano with small caldera overlies the big guyot.