• The Journal of Engineering Geology
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• v.20 no.2
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• pp.121-126
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• 2010

Current technology for radioactive waste disposal facility is operated as part of KURT site characterization in terms of reliability assessment is conducted to expand. In this study, a geological model of KURT surrounding area on the basis of flow characteristics of the site-scale hydrogeological study was about. Distributed in the study area into four boreholes were plotted using the stereo net NS, NW, EW, Low-angle fracture group was able to identify the components of geological models and include top soil layer, belt of weathering, Low-angle fracture zone, fracture zone was divided into. Separated by fracture of the hydraulic test of through the groundwater aquifer that provides the flow hydraulic conductivity and insulation hydraulic affecting the slope of the normal distribution for the size and direction by performing statistical analysis of fracture in the direction of local ns The advantage was confirmed. In addition, Low-angle fracture hydraulic conductivity of the value of 3.61e-07 m/s has a value greater than the major fracture, the fracture zones exist in the base rock and base rock and the hydraulic characteristics of the different methods applied and had to have a different interpretation judged by was.

• Journal of Environmental Impact Assessment
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• v.24 no.1
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• pp.51-65
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• 2015

The flora distributed around Mt. Hwangseok were summarized as 495 taxa including 97 families, 295 genera, 394 species, 4 subspecies, 80 varieties and 17 forms. In the component ratio of taxa, pteridophyta was 4.2%, 1.2% of gymnospermae, 78.8% of dicotyledonae and 15.8% of monocotyledonae. The rare plants were 9 taxa including Aconitum chiisanense, Eranthis stellata, Aristolochia contorta, Viola albida and so forth. The Korean endemic plants were 13 taxa including Populus tomentiglandulos, Pseudostellaria coreana, Aconitum pseudolaeve, Thalictrum actaefolium var. brevistylum and so forth. The specific plants by floristic region were 16 taxa including Cimicifuga heracleifolia, Sanguisorba longifolia, Symplocarpus renifolius, Betula davurica and so forth. The plants adaptable to climate change were 11 taxa including Aconitum pseudolaeve, Ajuga spectabilis, Carex okamotoi, Rhynchosia volubilis and so forth. The naturalized plants were 20 taxa including Fallopia convolvulus, Rumex crispus, Phytolacca amrericana, Robinia pseudoacacia and so forth. The invasive alien plant was Aster pilosus. The emergence of local ecologically important species, set the correct range for the core and buffer zone, transition zone, coded will be necessary, the distribution of the specialty plant areas and rare plants, an area management plan should be organized by nature. In addition, a variety of assessment techniques and accurate data to establish the validity of the core area is also set to acquire.

• Journal of the Korean Society of Groundwater Environment
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• v.1 no.1
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• pp.51-58
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• 1994

Electrical soundings and mappings were conducted to elucidate the geoelectrical structures of the local area of Cheju Island. The areas of the electrical surveys are coastal areas of Cheju Island, Gwagji, Sinpung-Sincheon. Generally, the geoelectrical structures of these areas are closely related with hydrogeological structures and it is very important to elucidate the geoelectrical structures for the water supply problems. Even though the results of electrical surveys in coastal areas of Cheju Island differ from place to place, there exists a general tendency of resistivity decrease with depth and the zone in the vicinity of mean sea level has low resistivity value. Also, there is good correlation between the low resistivity zone and the ground water distribution in the survey areas. A careful examination of the results of this study enabled resistivities of the rocks in Cheju Island to be divided in some categories. The resistivities of rocks unsaturated with ground water are greater than about 1000 ohm-m. The rocks saturated with fresh water have the resistivity value of about few hundreds ohm-m. Last, the rocks saturated with saline and/or brackish water have the resistivity value of about few tens ohm-m. The subsurface resistivity distribution of Cheju Island seems to be strongly dependent on the hydraulic characteristics of the rocks, and the amount and the salinity of the ground water in the rocks rather than the surface geology of the area.

• Journal of the Korean Institute of Landscape Architecture
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• v.47 no.6
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• pp.37-44
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• 2019

This study was conducted to identify the distribution characteristics of small village wetlands in Geumsan County, an inland mountain zone, and comparing with Seocheon County, a coastal plain area with different ecological environment characteristics. Using Arc-GIS (v10.1) the village wetland code was extracted to derive the possible location of the village wetland, and the final distribution of the village was obtained by performing indoor judging work based on satellite images, aerial photographs, topographical maps, Korea Land Information System (KLIS), land use level, land cover degree (division), and land use status by local surveying and indoor analyzing. Although Geumsan County (576.66km2) is more than 60% larger than Seocheon County (358.04km2), 607 villages in Geumsan County and 570 villages in Seocheon County are capable of making similar levels of 106.5% of wetlands, but only a fraction of those in Seocheon County were found to be 67.6%. The density of the village wetlands was much lower than that of Seocheon County, a coastal plain area, because there were many mountainous areas in Geumsan County, and most of the wetlands temporarily created for water supply were removed during the analysis phase of the Jeongsa Image, so the actual wetlands of the village were judged to be only two-thirds different from those of Seocheon County.

• Journal of Advanced Marine Engineering and Technology
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• v.11 no.2
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• pp.71-81
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• 1987

Nowadays, the high development of industrial technique demands the optimal design of marine structures to be welded under the water, because the underwater welding of the ship hull and marine structures can decrease manpower and cost of production. However there is not available at present any report on fatigue behavior about underwater welded joints. In this paper under tention- tension repeated fatigue stress with frequency of 10 cycles per second by local controlled system, the fatigue strength properties of underwater welded joints of SM41A-2 Plate-to-Plate of 10 mm thickness were experimentally examined. The results obtained were as follows : 1) The fatigue strength of underwater welded joints of SM41A-2 was peaked at the heat input of about 1, 400 joule/mm(180 A, 36 V), while, at the heat input of more than about 1, 100 joule/mm (160 A, 33 V) that of the underwater welds at the higher than cycle of life rather than the lower cycle was higher than that of the base metal but lower than that of the atmosphere welds on account of both cooling and notch effects. 2) The fatigue limit of underwater welds increased with an increase of heat input resulting in a peak of that at the heat input of about 1, 400 joule/mm and then decreased gradually. 3) The fatigue strength at N cycles was peaked between the heat input of about 1, 400 and 1, 700 joule/mm where the strain was rapidly increased. 4) It was confirmed that the optimal zone of heat input condition for obtaining the underwater welds fatigue strength higher than that of the base metal exists, and if out of this zone, the fatigue strength of the underwater welds was lower than that of the base metal because of lack weld penetration, inclusion of slag, voids, etc. 5) By the fatigue test, the underwater welds fractured brittly without visual deformation, so the strain was remarkably less than of the atmosphere welds. 6) The fatigue life factor was peaked at the heat input of about 1, 600 joule/mm (200 A, 36 V) at which the mean strain is a little higher than that of the base metal but quite lower than those of the atmosphere welds, resulting in good underwater welds because both fatigue strength and ductility of the underwater welds are higher than those of the base metal at such heat input.

• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.1
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• pp.1-8
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• 2012

To arrange effectively artificial reefs for marine afforestation, tidal currents were analyzed by numerical experiments, and particle tracking based upon tidal currents were carried out to clarify the path of algae spore. The experiments were carried out by EFDC (Environmental Fluid Dynamics Code), and water column was vertically divided 10 layers. Tidal current patterns showed to be affected by main current at outside of study area, and circle currents of two were observed from analysis of residual currents. Particle tracking were experimented for 15 days at 2 installation places in which artificial reefs for marine afforestation would be deployed. According to the results of particle tracking experiment, particle movement at St.1 showed belt type along coastal line, and St.2 showed ellipse type at 300~500 m distant from coastal line. It suggest that artificial reefs for marine afforestation should be installed belt zone at station of St.1 and ellipse zone at St.2. Modelling algae transport was also tested to account for local dispersion of algae spore due to the suspended materials.

• Journal of Radiation Protection and Research
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• v.27 no.3
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• pp.189-198
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• 2002

The time for evacuation of residents in emergency planning zone(EPZ) of Uljin nuclear site in case of a radiological emergency was estimated with traffic analysis. Evacuees were classified into 4 groups by considering population density, local jurisdictions, and whether they ate residents or transients. The survey to investigate the behavioral characteristics of the residents was made for 200 households and included a hypothetical scenario explaining the accident situation and questions such as dwelling place, time demand for evacuation preparation transportation means for evacuation, sheltering place, and evacuation direction. The microscopic traffic simulation model, CORSIM, was used to simulate the behavior of evacuating vehicles on networks. The results showed that the evacuation time required for total vehicles to move out from EPZ took longer in the daytime than at night in spite that the delay times at intersections were longer at night than in the daytime. This was analyzed due to the differences of the trip generation time distribution. To validate whether the CORSIM model fan appropriately simulate the congested traffic phenomena assumable in case of emergency, a benchmark study was conducted at an intersection without an actuated traffic signal near Uljin site during the traffic peak-time in the morning. This study indicated that the predicted output by the CORSIM model was in good agreement with the observed data. satisfying the purpose of this study.

• Journal of Korea Water Resources Association
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• v.50 no.3
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• pp.169-179
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• 2017

Recently, due to global warming and climate change in Korea, local heavy storm occurs frequently. In this study, the risky areas for flooding in urban areas are analyzed for flood inundation based on two-dimensional urban flood runoff model (XP-SWMM) focusing on coastal high flood-risk urban areas. In addition, the MCDM (Multi-Criteria Decision Making) technique is utilized in order to establish the flood defense structural measures. The alternative flood reduction method are compared and the optimum flood defense measures are selected. A simulation model was used with three structural flood prevention measures (drainage pipe construction, water detention, flood pumping station). In order to decrease the flooding area, flood assessment criteria are suggested (flooded area, maximum inundation depth, damaged residential area, construction cost). Priorities of alternatives are determined by using compromise programming. As a result, the optimal flood defence alternative suggested for Janghang Zone 1 is flood pumping station and for Janghang Zone 2, 3 are drainage pipe construction.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.1
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• pp.19-27
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• 2019

This study is to measure the length of the Demilitarized Zone and the Military Demarcation Line(MDL) on the Korean Peninsular. For this purpose, maps of the Armistice Agreement Volume II were used. These maps are nine sheets. In order to extract the MDL shown on the map, coordinates were assigned to the scanned image maps using the georeferencing module of ArcGIS based on the sheet line coordinates. The accuracy of the extracted vectors was checked by overlaying them on the maps of the Armistice Agreement Volume II. And I tried to validate these vectors through comparative analysis with vectors extracted from Kim(2007). Vectors extracted from Kim(2007) had errors in the curvilinear parts of the MDL, but the vectors extracted from this study exactly matched the MDL in the Armistice Agreement Volume II. The measured length is 239.42km(148.77miles). This means that the expression '155mile MDL' or '248km DMZ' in papers, reports or mass media has so far been inappropriate. I think this study will be able to provide information on the exact length of the DMZ in studies related with DMZ or in policy decisions by the national and local government. However, it is deemed necessary to verify this result by national organizations such as the NGII(National Geographic Information Institute). After these verification procedures, I hope that the national government will inform the people of the exact length of DMZ and MDL.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.170-181
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• 2020

In a situation where population decline is intensifying, the decline of local mid-small sized cities is emerging as a social problem. The decline will increase the difficulty of supplying demand-based living services. Therefore, increasing accessibility to living services is important for quality of life. With this background, the purpose of this study is to derive living zones that can use high-order services in metropolitan cities through high-speed railway. To this end, the behaviors of residents in mid-small sized cities were investigated through a questionnaire, and living zones and vulnerable areas were derived through a GIS analysis. The results of the study are summarized as follows. First, most of the residents had experience using cultural, medical, shopping, and educational services in metropolitan cities. Second, the time required to visit a metropolitan city for the use of higher-order services was about 2 hours, and the desired time was about 50 minutes. Third, when accessibility is improved, the willingness to use the higher-order service of the metropolitan city is high. Fourth, many regions have been derived as living zones where services of metropolitan cities can be used through high-speed rail. Lastly, the major vulnerable areas were found to be the northern area of the Gangwon region, the northern area of the Yeongnam region, the west coast of Chungnam, and the border area of Jeonnam and Gyeongnam.