• Journal of the Korean Institute of Landscape Architecture
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• v.15 no.1
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• pp.9-16
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• 1987

In Seoul metropolitan area, rockily denuded fores lands are widely distributed. Out of the rock-exposed hillslopes, Kwanak-Samsung mountains and Bookhan-Dobong mountains areas are the most severely eroded land at present To develope the rehabilitation measures for the rock-exposed hillslopes, it is essentially required that mechanisms of rock debris production and movement from the rock-exposed hillslopes should be studied. And also, suitable experiments for planting techniques should be practised at the field level. In this context, some experiments for the on-site fixation of the unstable stone-debris including plantation establishments on the rock-exposed hillslopes, have been carried out for 4 years from 1983 to 1986 at Kwanak mountain hillslopes. The results may be summarized as follows : 1) The soil environment-tolerable tree species for plantation extablishment on rock-exposed hillslopes include Buxus microphylla var. koreana, Forsythia koreana, Juniperus chinensis var. sargentii, Alnus hirsuta and Pinus rigida. These trees have, however, been showed fairly good growth performence at the places having more than about 30cm of soul layer depth above rock-bed. 2) In raising of seedlings to plant on the rock-exposed hillslopes, containerized seedling practices knave been appeared as the most adoptable measures. 3) In fixation of the unstable stole debris-and-sands on the on-site of rock. exposed hillslopes, the stone-lined barrier measures are more effective at comparatively large-sized places of rock-exposed hillslopes while the stone-bowed barrier measures are more effective at small-sifted isolated sold-debris places. The stone-buttressed terraces measures are more effective at the soil-composed hillslopes rather than rock-exposed hillslopes.

• Journal of Korean Society of Forest Science
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• v.76 no.1
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• pp.17-26
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• 1987

To develop the rehabilitation measures for rockily denuded forest lands which are widely distributed in Seoul metropolitan area, erosional characteristics of denudation should, first of all, be evaluated and analysed. As a fundamental study for developing such technical measures, the rockily denuded lands were classified into 6 types according to denudation features of the mountain land, and also movements of stone debris-and-sand on rock-exposed hillslopes were measured and analysed. The 6 basic types of denudation features include a) natural rock-outcrop-exposed land, b) stone debris-and-sand scattered land, c) stone debris-and-sand deposited land, d) coarse sand producing bare land susceptible to weathering and erosion, e) dwarfed pine growing land, and f) torrential valley susceptible to the debris slides. In the stone debris-and-sand scattered hillslopes (type b), average amount of moved-down debris reached to about 3.9 ton/ha/yr due to surface washing and slidings. In the particle size distribution of the moved-down debris, it amounts to about 25% of 10-25mm, about 15% of 5-10mm, about 24% of 2-5mm, and about 36% of less than 2mm in diameter class, respectively. The detailed experimental studies should be accomplished further more about the denudation processes including weathering, erosion and debris slides on rock-exposed hillslopes.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.1378-1385
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• 2008

The probability of landslide hazards was predicted to natural terrain around the stone relics of Jinjeon-saji area, which is located in Yangyang, Kangwon Province. As the analysis results of field investigation, laboratory test and geology and geomorphology data, the effect factors of landslides occurrence were evaluated, and then the landslides prediction map was made up by use of prediction model considering the effect factors. The susceptibility of stone relics induced by landslides was investigated as the grading classification of occurrence probability using the landslides prediction map. In the landslides prediction map, the high probability area of landslides over 70% of occurrence probability was 3,489m3, which was 10.1% of total prediction area. If landslides are occurred at the high elevation area, the three stories stone pagoda of Jinjeon-saji (National treasure No.122) and the stone lantern of Jinjeon-saji (Treasure No.439) will be collapsed by debris flow.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.2
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• pp.60.1-60.1
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• 2013

We study tidal disruption and subsequent mass fallback process for stars approaching supermassive black holes on bound orbits, by performing three dimensional Smoothed Particle Hydrodynamics simulations with a pseudo-Newtonian potential. We find that the mass fallback rate decays with the expected -5/3 power of time for parabolic orbits, albeit with a slight deviation due to the self-gravity of the stellar debris. For eccentric orbits, however, there is a critical value of the orbital eccentricity, significantly below which all of the stellar debris is bound to the supermassive black hole. All the mass therefore falls back to the supermassive black hole in a much shorter time than in the standard, parabolic case. The resultant mass fallback rate considerably exceeds the Eddington accretion rate and substantially differs from the -5/3 power of time. We also show that general relativistic precession is crucial for accretion disk formation via circularization of stellar debris from stars on moderately eccentric orbits.

• Journal of Korean Society of Forest Science
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• v.100 no.2
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• pp.283-291
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• 2011

The purpose of this study was to identify the public's preferences of different types of debris barriers and the impacts of construction materials, design, size, and planting on landscape preferences. On-site survey was carried out in Mt. Palgong during on December, 2009 and a total 122 visitors' data were analyzed. A total of 82 students Yeungnam and Donga University were also questioned in the classes during on December, 2009. Survey results showed that the debris barrier constructed with natural materials such as stone were more preferred and the level of planting around the debris barrier impacted most on the landscape preferences. The results imply that the importance of eco-friendly construction materials and methods has been increased in term of not only environmental conservation but also people's preferences. Therefore, the factors for enhancing landscape of debris barrier should be considered synthetically in terms of construction material, design, size, and planting level.

• Journal of Korean Society of Disaster and Security
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• v.14 no.1
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• pp.51-59
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• 2021

In Korea, where 64% of the soil is mountainous, typhoons and local rains concentrated in the summer season are frequent in mountainous disasters such as landslides and debris flow. The area of study was the area where the damage to the debris flow was caused by typhoon Mitag in October 2019, and all the houses located in the downstream area were damaged. In this study, numerical simulations were conducted on the area where the damage of earth and stone flow occurred using Hyper KANAKO model that can consider erosion and sedimentation, and the applicability of the model was examined by comparing the actual damage area and the analysis results of the model. As a result of the numerical simulation, the damage area of the debris flow in the target area was 53,875 m², the maximum flow depth was 2.4 m, and the average flow depth was 1.7 m.

• The Journal of Engineering Geology
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• v.18 no.3
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• pp.303-309
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• 2008

A probability of slope hazards was predicted at a natural terrain around the stone relics of Jinjeon-saji area, which is located in Yangyang, Kangwon Province. As the analyzing results of field investigation, laboratory test and geology and geomorphology data, the effect factors of landslides occurrence were evaluated. Also, the landslides prediction map was made up using the prediction model by the effect factors. The landslide susceptibility of stone relics was investigated as the grading classification of occurrence probability. In the landslides prediction map, the high probability area was $3,489m^2$ and it was 10.1% of total prediction area. The high probability area has over 70% of occurrence probability. If landslides are occurred at the predicted area, the three stories stone pagoda of Jinjeon-saji(National treasure No. 122) and the stone lantern of Jinjeon-saji(Treasure No.439) will be collapsed by debris flow.

• Journal of the Korean association of regional geographers
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• v.18 no.3
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• pp.253-267
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• 2012

The study looked into the type and characteristics of debris landforms in Mt. Mudeung. By focusing on the representative area, we aimed to categorize the debris landforms based on the morphologic and genetic characteristcis. The types of debris areas in Mt. Mudeung can be divided into the exposed debris type, mixed type of matrix, and the boulder-hidden type. Supply of block in the debris slope area displays different features depending on types of rocks. For the stony slopes of andesite, the block must be moved from the columnar joint or cliff in the upper part. The andesite debris slopes display dominant edge shape while displaying no round shape. The granite stony slopes display dominant round shape and the present exposed slope was assumed to be formed as the core stone which was deep weathered moved along slope during the periglacial era and the matrix was removed after post-glacial era. The movements of blocks are assumed to be caused by solifluction process. The joint area where granite and andesite areas meet, granite is located beneath andesite area, and this implies that blocks were actively freezing and creeping by solifluction and freezing and thawing at that time. It can be assumes that the granite matrix formed plain slope and then andesite boulder covered up the slope. Currently, the blocks in the stony slopes of Mt. Mudeung shows almost no mobility and the stony slopes created under periglacial climate can be considered to be fossil landform.

• The Journal of the Petrological Society of Korea
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• v.24 no.1
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• pp.1-10
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• 2015

Neulgeori prehistoric site is located at Joong-ri Kwanin-myon Pocheon-si, Gyeonggi-do, where lots of stone artefacts were excavated. We investigated the petrological features of the artefacts through petrographical observation and modal analysis. In addition we estimated the provenance of the artefacts by means of the geological survey. The twelve stone artefacts used in this study are identified as ash tuff, lapilli tuff, granite porphyry, andesite and diorite porphyry. Various rocks were used for making flakes, whereas blades and debris were from the tuffaceous rocks. Lapilli tuff is considered to have been delivered from the Dongmakgol tuff in the Cheolwon basin, granite porphyry from the Cretaceous granite porphyry stocks cropped out at the southeastern Oksan-ri and eastern Yeoncheon areas. Andesite artefact would have been originated from the outcrops located at the northern part of the site, and diorite porphyry artefact from the southern part of the site. The stone artefacts investigated are estimated to have been transported from the area within 15 kilometers from the site.

• Parasites, Hosts and Diseases
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• v.24 no.1
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• pp.89-94
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• 1986

The authors would record the fifth case of human fascioliasis in Korea, occurring in a 48 year old Korean man who lived in Munkyong, Kyongsangbuk-do. The diagnosis was based on the morphology and measurements of the eggs which were collected in necrotic debris from the tunnel-like ulcerations of the gallbladder wall which was surgically removed for a gall stone. Although we failed to find out the fluke in the specimen, there found an evidence of once presence of Fasciola in the inflamed wall of the gallbladder in this patient.