• Journal of Conservation Science
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• v.17 s.17
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• pp.83-94
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• 2005

Host rock or the standing sculptured Buddha in the Yongamsa temple is macular porphyritic biotite granite, which has gone through mechanical and chemical weathering. The rock around the Buddha statue is busily scattered with steep inclinations that are almost vertically discontinuous planes with the strikes of $N8^{\circ}E$. Especially the development of the joints that cross the major joints causes the structural instability of the rock. The rock of the Buddha statue is separated into several rock blocks because of many different discontinuity. Thus it is estimated that the bed rock has not only plane and toppling failure but also wedge failure in all the sides. Since the differential pressure is imposed on the body of the Buddha in the host rock, it is urgent to give a reinforce treatment of geotechnical engineering for the safe of its structural stability. Very contact area of joints have turned into soil, which promotes the growth of weeds and plant roots, then aggravates the mechanical weathering of the rock. Thus conservational treatments should also be considered to get rid of secondary contaminants and vegetation along the discontinuities and to prevent further damages.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.2
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• pp.49-67
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• 2020

This study was conducted to compare and analyze forest vegetation distributed in Geumosanseong-inside in Geumosan Provincial Park from 2017.10 to 2019.6. The vegetation structure was classified by the phytosociological method and TWINSPAN and the correlation between the community structure and the environmental factors was analyzed using DCCA ordination analydsis. The vegetation structures are Quercus mongolica, Fraxinus mandshurica, Q. acutissima, Larix leptolepis, Prunus padus and Morus alba community by the phytosociological method and 16 communities under TWINSPAN. The importance value of Q. mongolica(64.5) was the highest, and followed by F. mandshurica, L. leptolepis, Acer pseudosieboldianum, M. alba, P. padus, Q. acutissima, Sorbus alnifolia, P. serrulata var. pubescens, F. sieboldiana, Rhododendron schlippenbachii and Castanea crenata which is consistent with species having the dominance status by analysis of the vegetation structure. As the results of DBH analysis for taxon with high importance values, Q. mongolica and M. alba represented normal distribution, and thus, the dominance status of these species is likely to continue. L. leptolepis will maintain the dominance status due to high density of large individuals as compared with species above medium size. However, it will decrease because of high mortality after increase in age class. F. mandshurica and P. padus continue to show dominance status due to high density of young individuals as compared with species above medium size. Q. acutissima have high density of individuals above intermediate size and low density of young individuals, and thus, will maintain the dominance status. A. pseudosieboldianum, F. sieboldiana and R.schlippenbachii which are arborescent will present continuously high dominance status because of high density of young individuals. Soil analysis shows that whereas pH, Ca²⁺ and Mg²⁺ in the research area were lower than the average values of overall forest soil and O.M, T-N, C.E.C and P₂O₅ were higher. We expected that these results were due to agricultures until 50 years ago in Geumosanseong-inside. As a result of DCCA ordination analysis using eleven environmental factors and communities classified by the phytosociological method analysis showed that Q. mongolica was distributed in the environment with higher elevation and O.M and steep slope, and lower P₂O₅, Mg²⁺ and Ca²⁺. In contrast to F. mandshurica, Q. acutissima was distributed in higher K⁺ and lower pH. L. leptolepsis was distributed in various environment.

• Ocean and Polar Research
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• v.25 no.2
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• pp.213-226
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• 2003

Kongsfjorden near Korean Arctic Station, Dasan, is a glacial fjord in the Svalbard archipelago, Arctic that is influenced by both Atlantic and Arctic water masses. During the Arctic field season August 2002, surface temperature, salinity, density, and phytoplankton biomass (chi a) was measured in Kongsfjorden. A total of 15 surface samples were collected for the phytoplankton related measurements. Chl a values ranged from 0.08 to 1.4mg chi a $m^{-3}$ (mean of 0.53mg chl a $m^{-3}$) in the overall surface stations. The highest values of the chi a concentrations (> 1.0mg chi a $m^{-3}$) were found near glacier in the northeastern part of Kongsfjorden. Nanoplanktonic (< $20{\mu}m$) phytoflagellates were important contributors for the increase of the chi a. The nano-sized phytoflagellates accounted for more than 90% of the total chi a biomass in the study area. Surface temperatures and salinities ranged from 2.5 to $7.18^{\circ}C$ (mean of $4.65^{\circ}C$) and from 22.55 to 32.97 psu (mean of 30.16 psu), respectively. The physical factors were not highly correlated with phytoplankton distribution. The character of surface water due to down-fjord wind was highly similar to phytoplankton distribution. Drifting ice, freshwater, and semdiment inputs from large tidal glaciers located in the inner part of Konsfjorden create steep physico- and biogeochemical environmental gradients along the length of this ford. The glacial inputs cause reduced biodiversity biomass and productivity in the pelagic community in the inner fjord. Primary production of benthic and pelagic microalgae is reduced due to the limited light levels in the turbid and mixed inner waters. The magnitude of glacial effects diminishes towards the outer fjord. Kongsfjorden is an important feeding ground fer marine mammals and seabirds. Especially, seabirds play the largest energy intake and also export nutrients for primary production of the marine microalgae. Kongsfjorden has received a lot of research attention as a site for exploring the impacts of climate changes. Dasan Station in Kongsfjorden will be an important Arctic site for monitoring and detecting future environmental changes.

• Journal of the Korean association of regional geographers
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• v.16 no.2
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• pp.85-99
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• 2010

This study analyzes the geomorphic environments of river channels and properties of sediments in the Naeseong-River basin, a branch of Nakdong-River. While the area at NU1 located in the uppermost reaches indicates the landscapes with the gravel riverbeds, the sand riverbeds can be seen in the downstream of NU2 whose basin consists mostly of the granite regolith. The downstream of NU2 has the braided channels in the beds and this may be due to the large quantities of sand particles supply to the bed under the favorable geologic and geomorphic conditions, properties of river flowing within the floodplains less resistant to the erosion and great fluctuations of discharges. Whereas the river at NU2 may seem that sand particles are actively eroded during the high water-level periods, the particles may be actively deposited during the periods at NM2 and NL2. Moreover, in the reaches of NU2 to NM1 and NL1 to NL2, the mean grain sizes of sediments increase downstream suggesting the other supplies of coarse sediments from the lower order streams running the steep slopes because the river flows in the areas consisting of the metamorphic rocks rather than the granites and shows the properties of incised meander.

• Acta Via Serica
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• v.1 no.1
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• pp.95-104
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• 2016

The Silk Route in ancient times served as a link between the World's greatest civilizations and as a source of knowledge, art, religion and philosophy. This network of ancient caravan paths formed the first bridge between East and West, where two different civilizations came in contact with their respective cultural traditions and religious beliefs, as well as their scientific and technological achievements. One of the main routes of the Great Silk Route passed through the Karakoram, linking Kashgar with Kashmir and the Gandhara regions. The Karakoram Highway connects the Chinese province with Pakistan and follows the ancient Silk Route, which connected the Heartlands of Asia with the Western fringes and further beyond the entire continent of Europe. Evidences of the history of humankind, ranging from Pre-historic times to the spread of Buddhism from South Asia to China and the Far East, is depicted in the rocky cliffs on the waysides and on rough boulders scattered in the upper valley of the Indus River and its tributaries. The ancient trade routes also carried scholars, teachers, missionaries and monks of different beliefs and practices, who met and exchanged ideas. The Buddhists as well as Zoroastrians and other missionaries all followed the Silk Route, leaving permanent footprints of their passage. The ancient greater Gandhara is situated in the North-West of the Indian Sub-continent, with the steep mountain ranges of the Karakoram, the Pamir and the Hindu-Kush bordering it and the dry areas of Central Asia to its rear. A number of races from Central Asia migrated to Gandhara because of its mild climate and plentiful farm products and fruits. This area was an entry point of Western Culture into India and at the same times the exit point of Indian Culture, including Buddhism, to the West. In Gandhara, the diffusion of different cultures developed an art form, during the 1-7th centuries CE commonly known after its geographic name as "Gandhara Art". The Buddhism's route of introduction into China originated in Gandhara, then reached in Korea and Japan and other countries. The fame of Gandhara however, rested on its capital, "Taxila" which was a great centre of learning. From the time of the Achaemenians, down through Muslim period, Gandhara continued to establish and maintain a link between East & West, as shown by material evidences recovered from Taxila and other Buddhist centres of Gandhara during the course of archaeological excavations.

• 한국해양학회지
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• v.29 no.3
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• pp.217-227
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• 1994

From northeast to southwest, discontinuous sand ridges distribute on the western continental shelf of Korean Peninsular. The dimension of sand ridges is 3 to 21 m high, 3.1 to 6.8 km wavelength and 9-64 km long with 0.5 steep slope. they are probably originated and reformed by the intensity of tidal current according to the sea level rise. The characteristics of sand ridges revealed in study area are summarized as follows: (1) The sand ridges line up with the long axes of the tidal current ellipses, indicating a tidal control. (2) these are composed of two sedimentary sequences on the 3.5 kHz seismic profiles and core sediments. The upper sequence characterized by prolonged type is covered with thin veneer of massive fine sand(Mz, 2-3$\phi$) with Olive Gray(5Y 5/2). The lower sequence is characterized by internal reflector type with parallel and discontinuous. It consists of sandy mud or muddy sand(Mz, 5-7$\phi$) with laminar structures. the parallel internal reflectors are truncated on the slope of sand ridges. (3) Asymmetrical sand waves are superimposed on the sand ridges, and facing to the crest. However, symmetrical sand waves lie on the crest. Sand ridges having characteristics above is originated by scouring of tidal current, covered with coarase relict sediments, and modified by sadware.

• Journal of Korean Society for Atmospheric Environment
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• v.33 no.2
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• pp.159-173
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• 2017

The Weather Research and Forecast (WRF) - Community Multiscale Air Quality (CMAQ) system was applied to investigate the influence of major point sources located in Chungcheongnam-do (CN) on surface $PM_{2.5}$ (Particulate Matter of which diameter is $2.5{\mu}m$ or less) concentrations in its surrounding areas. Uncertainties associated with contribution estimations were examined through cross-comparison of modeling results using various combinations of model inputs and setups; two meteorological datasets developed with WRF for 2010 and 2014, and two domestic emission inventories for 2010 and 2013 were used to estimate contributions of major point sources in CN. The results show that contributions of major point sources in CN to annual $PM_{2.5}$ concentrations over Seoul, Incheon, Gyeonggi, and CN ranged $0.51{\sim}1.63{\mu}g/m^3$, $0.71{\sim}1.62{\mu}g/m^3$, $0.63{\sim}1.66{\mu}g/m^3$, and $1.04{\sim}1.86{\mu}g/m^3$, respectively, depending on meteorology and emission inventory choice. It indicates that the contributions over the surrounding areas can be affected by model inputs significantly. Nitrate was the most dominant $PM_{2.5}$ component that was increased by major point sources in CN followed by sulfate, ammonium, and others. Based on the model simulations, it was estimated that primary $PM_{2.5}$ $(PPM)-to-PM_{2.5}$ conversion rates were 41.3~50.7 ($10^{-6}{\mu}g/m^3/TPY$) for CN, and 12.4~18.3 ($10^{-6}{\mu}g/m^3/TPY$) for Seoul, Incheon, and Gyeonggi, respectively. In addition, spatial gradients of PPM contributions show very steep trends. $NO_X$-to-nitrate conversion rates were 7.61~12.3 ($10^{-6}{\mu}g/m^3/TPY$) for CN, and 3.94~11.3 ($10^{-6}{\mu}g/m^3/TPY$) for the sub-regions in the SMA. $SO_2$-to-sulfate conversion rates were 4.04~5.28 ($10^{-6}{\mu}g/m^3/TPY$) for CN, and 3.73~4.43 ($10^{-6}{\mu}g/m^3/TPY$) for the SMA, respectively.

• Journal of Korean Society of Forest Science
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• v.90 no.3
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• pp.363-372
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• 2001

The objective of this study was to investigate the site and growth characteristics of dominating Cornus controversa in the hardwood stands at Mt. Gariwang and Mt. Joongwang area located in Pyungchang-gun, Kangwon-do. The C. controversa was mainly distributed at the rather steep slope and aspect facing from northeast to northwest, and altitudes ranging from 800 to 1,100m. The C. controversa grew at relatively deep A soil layer with high moisture and nutrients. Major competing species in upper stories were Quercus mongolica, Acer mandshuricum, Salix hulteni, Acer pictum, and herb plants such as Polystichum tripteron, Dryopteris crassirhizoma, Meehania urticifolia, Pseudostellaria pahbiniana, Ligularia fischeri, Impatiens noli-tangere, Corydalis speciosa in the floor. The average annual diameter growth of C. controversa according to the altitude was $4.06({\pm}0.90)mm$ below 900m, $2.51({\pm}0.65)mm$ from 900 to 1,000m, $3.28({\pm}0.12)mm$ from 1,000m to 1,100m and $2.81({\pm}0.35)mm$ above 1,100m. Good annual growth was shown at northwest site, but no difference due to micro-topography.

• Ocean and Polar Research
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• v.32 no.4
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• pp.337-350
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• 2010

This study conducted sedimentological and geophysical surveys for 3 years (2006-2008) in southern Gyeonggi Bay, Korea to elucidate temporal changes in subaqueous dune morphology on a sand ridge trending northeast to southwest that has been excavated by marine sand mining. The sand ridge (~20 m in height, ~2 km in width and 3~4 km in length) has a steep slope on the NW side and a gentle slope on the SE side, creating an asymmetric profile. Large (10~100 m in length) and very large (>100 m in length) dunes occurring on the SE side of the ridge show a northeastward asymmetrical shape, whereas dunes on the NW side destroyed by marine sand mining display a southwestward asymmetry. The comparison between Flemming (1988)'s correlation and the height-length correlation of this study indicates that tidal current and availability of sand sediment are major controlling factors to the development and maintenance of dunes. Depth and sedimentary characteristics (grain size) are not likely to be major controlling factors, but indirectly influence dune growth by hydrological and sedimentary processes. The length and the height of dunes decrease toward the southeastern trough away from the crest of the ridge. These features result from the decrease of tidal current and sediment availability. The length and the height of dunes on the southeast side decrease gradually over time. This is a result of the interaction between tidal current and the decrease in sediment availability due to sediment extraction by marine sand mining. Marine sand mining has destroyed the dunes directly, causing irregular shapes of shorter length and lower height. The coarse fraction of suspended sediments is transported and deposited very close to the sand pit. By contrast, relatively fine sediments are transported by the tidal current and deposited over a wide range by the settling-lag effect, resulting in a decrease of sediment grain size in the area where suspended sediments are deposited. In addition, marine sand mining, decreases the height of dunes. Therefore, morphological and sedimentological characteristics of dunes around the sand pits will be significantly changed by future sand mining activities.

• Journal of the Korean Electrochemical Society
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• v.4 no.3
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• pp.125-131
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• 2001

A long-term variation of electrode polarization in the MCFC has been analyzed successfully using a single cell with a Au, $CO_2/O_2$ reference electrode Four different cells with different components were operated and their electrode polarizations were analyzed. As published in the literatures, the cathode polarization was larger than that of the anode. The more stable operation of a single cell with the Al-coated cell frame up to 6,000hrs indicates that the corrosion at the cell frame, particularly wet seal area, plays an important role to determine the lifetime of a MCFC. At the initial stage of the cell operation, the voltage of the cell using a cathode stabilized by the $LiCoO_2$ coating was relatively low due to the high cathode polarization. As the cell was operated and the stabilized cathode was lithiated sufficiently, the cathode polarization decreased and the cell voltage was recovered. It was observed that the voltage of the cell using the $Li_2CO_3/Na_2CO_3$ electrolyte fluctuated with operation time and the cathode polarization fluctuated along with the cell voltage quite similarly. Although the mechanisms of the voltage fluctuation were not clear yet, the results imply that the voltage fluctuation was related with a reaction in the cathode side. After testing every single cell, the cathode polarization increased with the steep decrease in the cell voltage. Thus, the cathode should be improved in order to develop more durable MCFC.