• The Journal of Engineering Geology
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• v.11 no.1
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• pp.101-113
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• 2001

Structural and geological engineering properties of the rock mass distributed in the Yokmang mountain area were investigated to detenninc the usable cut-out volume and quarrying efficiency. The study area is located in the southern tip of the Yangsan fault system which controls the geological structure of the Kvungsang basin. As a result, the study area is mainly composed of andesicic. rhyolitic. and granitic rocks of the Cretaceous Kyungsang Supergroup and a series of right-handed strike-slip faults is developed along NNE-SSW direction. These regional faults significantly affect the spatial and meclwnical characteristics of joints such as spacing, frequency, and compressive strength. The joint frequency is highest along the fault zones and decreases toward the remote region. Based on the geological information obtained from the field survey, the detailed structure of the Yokmang mountain was analyzed and the volume of the rock mass was assessed. Considering the minimum rock block size required for the construction of a coastal dumping site, potential cut-out volume is then estimated to be 4,018,000m$^3$ the volume % of which is 48% of Yokmang mountain including the soil and weathered rock and 61% of the unweathered rock mass.

• The Journal of Engineering Geology
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• v.14 no.2
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• pp.211-222
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• 2004

In this study, a probabilistic prediction model for debris flow occurrence was developed using a logistic regression analysis. The model can be applicable to metamorphic rocks and granite area. order to develop the prediction model, detailed field survey and laboratory soil tests were conducted both in the northern and the southern Gyeonggi province and in Sangju, Gyeongbuk province, Korea. The seven landslide triggering factors were selected by a logistic regression analysis as well as several basic statistical analyses. The seven factors consist of two topographic factors and five geological and geotechnical factors. The model assigns a weight value to each selected factor. The verification results reveal that the model has 90.74% of prediction accuracy. Therefore, it is possible to predict landslide occurrence in a probabilistic and quantitative manner.

• Journal of Environmental Impact Assessment
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• v.12 no.3
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• pp.137-150
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• 2003

This study aims to survey whether local governments have legislated laws and regulations on environment impact assessment system, to compare and analyze specific projects and their scale, assessment items, and procedures & discussion process, to identify issues and generate improvement plans, and to suggest a direction for future legislation to local governments that plan to legislate laws and regulations in the future. Major outcome of the study are as follows. First, terminologies used for environment impact assessment by local governments need to be unified. Also, laws and regulations need to be legislated soon. Second, in "urban development project" areas, a total of nine project areas including "quarrying of soil and stone, sand, gravel, and minerals" was essential common projects. A total of six project types were added or newly established compared to national systems. Among them, four project types were added within national-level project areas and two project types were not available under the national-level project areas and newly added due to the nature of local governments. Third, in terms of project scale, scale enhancement of "urban development project" was most common. Analysis showed that in case of clean natural environment such as Cheju Island, it is necessary to consider reinforcing project areas where development activities take place directly in forests or rivers such as "industrial base and complex development", "water resource development", and "development of tourism complex." Fourth, the discussion and review procedures of assessment reports were similar to those at government level. However, in case of Seoul city, it is required to write a "preparation plan" before drafting an assessment report. The city features partial introduction of scoping and screening, which allows to exempt discussion procedures if impact on environment is found to be minimal after drafting the assessment report. In case of national-level, it has a dual system that is split between Ministry of Construction and Transportation and Ministry of Environment. However, in case of environment impact assessment of local governments, it is a single system where city mayors and provincial governors are in charge of both project execution and environmental assessment. Therefore, the most important task is how to satisfy objectiveness and accountability.

• Journal of Environmental Impact Assessment
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• v.19 no.1
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• pp.49-57
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• 2010

The objective of the research is to analyze changing trend of water discharge in precipitation, according to changing land use, through an environment-friendly urban development method called LID. The study chose S1 basin (Separated Sewer districts) in Cheongju region for survey. Among LID methods, relatively more applicable methods of green rooftop space and parking lot with permeable material were selected to construct plausible scenarios. Curve Number (CN) value was calculated due to land use patterns in each scenario, and SWMM model simulation were conducted during 2008 for comparative analysis. For Case 1, only parking lot with permeable material was applied to the scenario. Green rooftop space I and II were applied to Case 2 and 3 respectively. For Case 4 and 5, green rooftop space I and II were applied, in addition to parking lot with permeable material, Calculation of CN value showed that for S1 basin, the value was 88.1 (prior to scenario application), 86.5 (Case 1), 81.9 (Case 2), 68.5 (Case 3), 80.4 (Case 4) and 67.2 (Case 5). Changing pattern of rain water discharge was analyzed for each scenario. For Case 1, the change was not remarkable before and after application of scenario. In Case 2 and 4, the impact of rain water discharge as source of pollutant fell to 20~30%. The rate dropped to 30~50% in Case 3 and 5 respectively. The result demonstrates that the amount of rain water discharge, amount and frequency of sewer overflow, frequency of rain water discharge, and pollution load decreased in accordance with declining CN value in each scenario. In installing green rooftop space, the effect was twice greater when rain water discharge was directly infiltrated into soil.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.1
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• pp.57-65
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• 2011

The composition of species for each community of Quercus by vegetation and soil survey, the community classification by TWINSPAN, the structural characteristics of communities were used and analyzed during the period of 2000~2004 for Quercus mongolica forest. And the resulting suggestions for a subsequent planting model for forest are as follows. The Quercus mongolica community had the highest importance value for Quercus mongolica followed sequentially by Acer pseudosieboldianum, Acer mono, Rhododendron schlippenbachii, Tilia amurensis, Fraxinus rhynchophylla, and Fraxinus sieboldiana. As a result of suggesting a planting modeling for the Quercus mongolica communities in the areas with the warmth index of both $60.90{\sim}79.79^{\circ}C$ and $53.96{\sim}64.82^{\circ}C$, Quercus mongolica was absolutely dominant in case of the subtree layer for the accompaniment species of distribution in the planting modeling by tree layer in the two areas depending on the warmth index, while there were distinct differences shown in case of the lower tree layer. While Acer pseudosieboldianum, Tilia amurensis, Fraxinus rhynchophylla, Sorbus alnifolia, Acer mono, etc. were appeared in the subtree layer for the areas with the warmth index of $60.90{\sim}79.79^{\circ}C$. Cornus controversa, Quercus mongolica, Fraxinus sieboldiana, etc. were many appeared in the subtree layer for the areas with the warmth index of $53.96{\sim}64.82^{\circ}C$. And, when we made ecological Quercus mongolica community, subtree layer planting is different by warmth index.

• Applied Biological Chemistry
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• v.23 no.3
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• pp.178-183
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• 1980

Citrus fruits harvested in 1979 were collected from markets scattered in Jeju and Seogwipo area on Jeju island and also from citrus orchards with five, ten, fifteen, twenty, and thirty years of cultivation history. Organophorous insecticides and organochloro acaricides in the pulp of fruits were analysed by gas liquid chromatograph. It was found that EPN and Kelthane were most significant residues found in the citrus fruits in terms of both level and frequency of occurrence. Among citrus fruits collected from various markets, EPN was detected in 28% of the fruits samples in the range of 0.009 to 0.025 ppm, while Kelthane, at lower level, was found in all citrus fruits in the range of trace to 0.007 ppm. Residue levels of citrus fruits from orchards of various cultivated periods, in general, confirmed those of the fruits collected from commercial markets. However, residues of Kelthane in the citrus fruits tended to increase with orchards having longer cultivation history.

• Weed & Turfgrass Science
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• v.6 no.4
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• pp.355-358
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• 2017

Amur silver grass, Miscanthus sacchariflorus is one of the promising biofuel weeds. A damage of noctuid pest, Leucapamea askoldis was firstly observed from Amur silver grass in Hwasun silver grass plantation during the survey of insect pests of Amur silver grass in Iksan, Hwasun, and Sancheong plantation areas in Korea. The host of L. askoldis was not known yet in Korea. The L. askoldis damage was observed as larval feeding on newly grown shoots and roots of M. sacchariflorus close to soil surface from early May in 2013. Investigated larval density was $1.6{\pm}1.1per\;m^2$ on April 4 and damage rate of shoots was $0.8{\pm}0.4%$ on May 4, 2013. The larvae bore into shoots of M. sacchariflorus and feed on the inside of plant. The damaged shoots are easily pulled out and distinguished by the boring hole on the shoots. L. askoldis was potential insect pest in M. sacchariflorus plantation areas.

• Journal of Environmental Science International
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• v.20 no.4
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• pp.527-540
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• 2011

The investigation was made about distribution and ecological characteristics of Rhododendron mucronulatum var. mucronulatum, R. dauricum and R. schlippenbachii on Mt. Changbai in China. The Ericaceae plants are known to be highly ornamental and easy to cultivate. The results of investigations are like followings. The plant species diversity was the highest in habitats of R. mucronulatum var. mucronulatum, followed by those of R. schlippenbachii and R. dauricum. R. mucronulatum var. mucronulatum community was found in the northwest exposure areas of 300m in altitude. Corylus heterophylla, Carex humilis var. nana, Atractylodes japonica species also grew in the R. mucronulatum var. mucronulatum community. R. dauricum communities were widely distributed in the west exposure areas of 1226-1860m above sea level. R. schlippenbachii populations were found in areas of under 300m above sea level, which has dry soil. But humidity of air was relatively high in the place. Artemisia japonica, Lespedeza bicolor and Dactylis glomerata were found around the habitats of R. schlippenbachii. Phalanx type of plants were dominant near the habitats of Ericaceae plants as 61%. Further, there appeared higher plant life totalling to 72 taxa comprising 54 species, 16 varieties and 2 forma with 31 families and 59 genuses at the whole survey area. Among these, Compositae plants excellent in resistance to environment was surveyed the most, accounting for 30.0%.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.10 no.2
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• pp.79-90
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• 1990

The National Construction Research Institute of Korea has measured the depth of the frozen ground covering all the areas of South Korea during ten years ranging through 1980. The measurements were made for the frozen ground at random but intended for the most frost-susceptible soils. The soils of the frozen ground were sampled and then classifide into four groups according to the frost design soil classification system suggested by the Corps of Engineers of the United States. The contours of the maximum depth of the frost penetration are drawn on a map with data collected during the ten years. Also isolines of the design frezing index are shown on an another map using the metorological information of 1980-1989 and compared whth those in vestigated in 1980 by Highway Survey Team of the Ministry of Construction, Korea. It is known that the maximum depth of the frost penetration is related to freezing index values. An empirical formula expressing the relation is suggsted, in which the depth is proportional to the one-third power of the air freezing index values.

• Parasites, Hosts and Diseases
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• v.32 no.4
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• pp.207-214
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• 1994

The prevalence of intestinal parasites and CLonorchis sinensis infection was observed among inhabitants in the upper stream of Kumgang (River) from Junuary to October 1991. A total of 743 fecal specimens was examined by cellophane thick smear and formalin-ether concentration technique. The parasite positive rate including helminth eggs and protozoan cysts was 40.8%, the positive rates for every species were: Clonorchis sinensis 30.8%, Metqgonimur app. 14.5%, Fosciolc spry. 0.7%, Tqsnia app. 1.5%, Asccris lumbricoides 0.4%, Enterobius vermicularis 0.1%, Hookworm 0.1%, Trichuris kichiura 1.6%, Entamoeba coli 0.7%, E. histolytica 0.3%, Endolimox nana 0.3%, Giardia lamblia 0.3% and lodamoebc buetschlii 0.1%, respectively. The cumulative positive rate in Okchon-gun showed 51.1%, in the Kumsan-gun 50.8% and in the Muju-gun 28.6%. Through this survey, it was concluded that the soil transmitted intestinal parasites including helminthseggs and protozoan cysts have been decreased remarkably among the inhabitants along the upper stream of Taechong Dam, Kum-gang (River), on the other side, Clonorchis sinensis, Metogonimw app. and Tuenin sap. are still inorderate prevalent. Key words: Intestinal parasites, Clonorchis sinensis, Metogonimus app. Fasciolc sup. Kumgang (River).