• Journal of Korean Society for Geospatial Information Science
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• v.19 no.3
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• pp.33-40
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• 2011

This paper presents the prediction and evaluation of landslide using LRA(logistic regression analysis) and ANN (Artificial Neural Network) methods. In order to assess the landslide, we selected Sarabong, Byeoldobong area and Mt. Song-ak in Jeju Island. Five factors which affect the landslide were selected as: slope angle, elevation, porosity, dry density, permeability. So as to predict and evaluate the landslide, firstly the weight value of each factor was analyzed by LRA(logistic regression analysis) and ANN(Artificial Neural Network) methods. Then we got two prediction maps using AcrView software through GIS(Geographic Information System) method. The comparative analysis reveals that the slope angle and porosity play important roles in landslide. Prediction map generated by LRA method is more accurate than ANN method in Jeju. From the prediction map, we found that the most dangerous area is distributed around the road and path.

• The Journal of Engineering Geology
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• v.17 no.3
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• pp.339-350
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• 2007

Content, swelling, concentration, drainage of clay are critical factors that could control rock failures as well as discontinuous geological structures like faults and joints. Especially, the proportional components of clay minerals can be one of few direct indicators to a rock failure caused well by rainfall. Criticality of the role of clay mineral contents gets bigger in the slope and tunnel design. This study, using a horizontal boring core of pelitic/psammitic phyllite from the OO tunnel construction site, aims to investigate mineral composition changes related to fault distribution and their mechanical effects to the activity of these discontinuous layers (i.e., clay-filled fault layers), and eventually to define correlation among rock compositions, weathering products and rock instabilities. Field survey and lab tests were carried out for the composition and strength index of fault clay minerals within the core samples and microscopic analysis of fresh and weathered rock samples.

• Journal of the Korean Geographical Society
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• v.41 no.2 s.113
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• pp.139-149
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• 2006

Earlier research works focused on the seasonal patterns and bio-geochemical processes in sand dunes, and the satellite data and aerial photographs have been used only as a backdrop or for the multi-temporal delineation of sand dune area. In order to find the optimal way to extract features' characteristics, Gimnyeong sand dune area was selected as a study site. Field works have been carried out three times to collect ground control points and sand samples for laboratory analyses. The texture of sand dune is classified as fine sand, which has been derived from shell fragments. The sand dune penetrated into the island from northwest to southeast direction. An aerial photograph was re-sampled into one-meter resolution and rectified with software including Erdas Imagine and ENVI. Sub-scenes were chosen as samples for sand dune, urban area and rural area. K-group non-parametric analysis had been done for the geometric and spectral values of enclosed texture patches. Urban areas proved to have significant smaller patches than the others.

• Korean Journal of Environment and Ecology
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• v.21 no.1
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• pp.1-12
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• 2007

Nauralized plants in Ulleungdo were enlisted as 65 taxa, 21 families,49 genera,63 species and 2 varieties by field survey and flora lists of literature cited. Family Compositae covered 27.7% and Family Gramineae, Family Leguminosae and Family Polygonaceae covered 7.7% each. In this study, the nine taxa such as Rumex nipponicus, Trifolium campestre, Oxalis articulata, Anthriscus caucalis, Ipomoea purpurea, Coreopsis Ianceolata, Galinsoga parviflora, Tritonia crocosmaeflora and Festuca arundinacea are added as Nauralized plants in Ulleungdo. Annual plants ratio is 36.9% by life-form spectrum and Europe ratio is 40.0% by origin. The Urbanization Index was 22.0 and the Ratio of Naturalized has increased by flora lists of literature cited each. Ambrosia artemisiifolia var. elatior is growing in Ulleungdo by a plant cause disturbance. Spread prevention and minimization incoming of gardening plants by management plan of naturalized plants might be required. Moreover, it is needed to induce the succession for the recovery of the cut-slope using the native plants.

• Korean journal of applied entomology
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• v.27 no.1
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• pp.21-27
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• 1988

A study was carried out to investigate the morphological characteristics and life histories of H. morosa and H. diomPhalia during the period from 1984 to 1986. The head capsule width and bOdy length of H. Morosa larvae were slightly greater than those of H. diomPhalia. Otherwise, the two species looked very similar and were hard to be differentiated from each other in all life stages. H. morosa adults emerged in late June and laid eggs in soil during the period between mid July and mid August. Larvae developed by September to the last(3rd) instar which overwintered to pupate in late May. H. diomPhalia adults emerged from mid August but remained under the soil until next spring after which females laid eggs in soil from late May to early July. Larvae developed in most cases to the last instar by September and overwintered thereafter. Unlike H. morosa, they resumed feeding next April and began to pupate in late July. The egg periods of H. morosa and H. diomPhalia did not significantly differ but the larval and pupal periods of the latter were longer than those of the former.

• Journal of the Korean Geographical Society
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• v.51 no.6
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• pp.739-759
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• 2016

C. Gottsche(1855-1909), the Deutsch geologist, was invited by $M{\ddot{o}}llendorff$ who was the viceminister of foreign affairs in Korea, and travelled through the inland of Korean peninsula in 1884. He covered 2,550km in 138 days. After that journey, he wrote three academic papers about the geography and geology of Korea with the data of that field trip. Those paper bear considerable significance in that they included the first approaches to Korean geography and geology by a field-scientist with a modern academic training. Unlike other two papers focusing on the geology or the minerals, "The Geography of Korea(${\ddot{U}}ber$ Land und Leute in Korea(1886))" has its own value as a historical document, because it shows how the contempory Korea actually appeared to the eye of a $19^{th}$ western field-scientist. As this has not been introduced in Korean acdemic journals yet, this study might contribute to the understanding of how westerners regarded Korea in the end of 19th century.

• Korean journal of applied entomology
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• v.56 no.4
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• pp.439-440
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• 2017

The obscure mealybug, Pseudococcus viburni Signoret (Hemiptera: Pseudococcidae) is a polyphagous cosmopolitan pest, damaging vineyards and fruit orchards. The species has long been quarantined in Korea and has never been recorded in the wild in Korea. In this study, to confirm the absence of P. viburni in Korea, we have searched for the species from the orchards. 533 sites of persimmon orchards, 144 sites of apple and other orchards, and 281 sites of nurseries and greenhouses were surveyed for the last three years (2015-2017). As a result, P. viburni occurs neither in the wild nor in nurseries in Korea.

• Spatial Information Research
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• v.14 no.3 s.38
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• pp.285-297
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• 2006

We aim to investigate the morphological and environmental characteristics of royal tombs of Chosun Dynasty by using GIS technique and remotely-sensed data. Most of the royal tombs are located on the banded gneiss and granite and over the south- and east. facing slopes and have altitudinal ranges of 150 to 200 meters. Due to the time gaps, exact locational preferences of the royal families can not be understood at this moment and also proximity to the running water is hard to be quantified. Close examination of Gwangneung indicates that the artificial modification and weathering have severe impacts on the slope and stone artefacts. The results from this research can be useful to preserve the valueless cultural heritages.

• Analytical Science and Technology
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• v.13 no.1
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• pp.34-40
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• 2000

The optimum conditions for the half-life time and residual analysis of the iminoactadine triacetate fungicide on soils were investigated by using the gas chromatography. Iminoctadine triacetate(IOTA) was extracted from soils with 2.0 M-NaOH/methanol and chloroform. The extracted IOTA was derivatized to pyrimidine hexafluroacetylacetone by the acetylation and analyzed with GC/ECD after elimination of moisture and impurities on the Sep-Pak column. From the standard addition experiments with 0.1 and 1.0 ppm, the average recoveries were ranged from 83.8 to 93.2 % and the detection limit was 0.005 ppm. The half-life time of iminoctadine triacetate in the silty clay was 30 days in the laboratory and 19.5 days in the field test whereas it was 27 days and 17.5 days for each in case of silty loam.

• Journal of Wetlands Research
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• v.12 no.2
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• pp.1-12
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• 2010

This study examined geological characteristics of a wetland in Mountain Geumjeong in Busan Metropolitan City. Field survey and laboratory tests were performed to identify topographic features, geological and structural geological characteristics, rock strength along the distance from the wetland, soil profile in the wetland, and chemical property of the wetland soil. The bedrock of the wetland consists of hornblende granite. Hornblende granite and rhyolitic rock around the wetland have the joints with strikes of N-S, E-W, and NE-SW directions and with higher dips greater than $60^{\circ}$. Lower rock strength and higher weathering grades take place towards the wetlands. According to X-ray diffraction analysis of wetland soil samples, kaolinite, montmorillonite, and gibbsite appear which demonstrate weathered products of feldspars in the hornblende granite. The soil profile in the wetland comprises O, A, B, and C horizons from the land surface. The contents of the organic matters decrease from shallow parts to deeper parts of the soil profile. In addition, $K^+$ and $Na^+$ originating from the weathering of feldspars are dominant components among inorganic ions in the wetland soil.