• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.223-224
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• 2004

고준위폐기물 혹은 사용후 핵연료의 처분용기 재질은 각 국의 처분개념과 처분공의 주위 환경에 따라 달라질 수 있다. 용기의 후보재질로는 탄소강, 스텐레스 강, 구리, 니켈, 티탄 혹은 이들의 합금이 주로 고려되고 있으나, 국내에서는 아직 선정되지 않았다. 국내 처분환경에서 이들 재질의 부식특성을 조사하고자 모의 화강암 지하수를 가해 만든 겔 상태의 경주 벤토나이트에 탄소강, 스텐레스 강, 구리 시편을 넣고, $70^{\circ}C$, 아르곤 분위기에서 530일 경과한 후 시편의 표면 변화 (그림 1) 및 무게 감소를 측정하였다. 철 부식시편은 검정색의 철 화합물 층으로 덮여 있었으며, 구리표면에는 노란색의 부식층이 형성되었는데, 이를 XRD로 분석한 결과 $Cu_2O$로 판명되었다. 그러나 $700^{\circ}C$에서 각각 0, 24, 96시간동안 예민화시킨 스텐레스 강 시편들은 모두 초기상태 그대로 광택을 유지하고 있었으며, XRD에서 다른 화합물의 형성을 발견할 수 없었다 (그림 2). 시편의 무게 감소가 균일부식에 기인한 것으로 가정하여 환산한 결과, 구리와 스텐레스 강 모두 0.3~0.4 $\mu\textrm{m}/yr$의 부식속도를 나타내었다. 그러나 구리는 부식생성물이 표면에 부착되어 있기 때문에 실제 부식두께는 이 값보다 더 클 것으로 생각된다. 용기가 초기 530일간과 같은 속도로 처분용기의 부식이 진행된다면 한국에서 기준처분 개념으로 삼고 있는 50mm 두께의 내부식성 외벽 금속용기는 적어도 만년이상 견딜 수 있을 것으로 추정된다. 한편, 검정색 부식층을 제거한 무게감소로부터 계산한 철의 부식속도는 구리의 약 30배에 해당하였다. 금속 재질의 정확한 부식 거동을 파악하기 위해서는 보다 장기간의 실험이 요구된다. 시험법 선정에 각계(규제기관, 학계, 발전소 현장 및 산업계 등) 전문가로부터 기술자문회의를 통하여 자문 의견을 받기로 하였다. 특히 현재 폐기물 인수 기술기준치가 설정된 국가의 시험법을 심층 있게 검토하기로 하였다.검토하기로 하였다. 혹은 수성주변 환경이 지배하는 산악이나 구릉지에서 흔히 나타나는 침엽수-낙엽활엽수의 혼합림 식생상태를 잘 대변해 주고 있는 것으로 판단된다. 끝으로, 의림지 호저 퇴적층 중에서 인위적인 교란흔적이 없는 암회색 유기질 니층에 대한 탄소연대측정 결과, 제1호공 12번 시료에서 950$\pm$40 years B.P을 얻었으며, 제3-1호공에서도 아래로 내려가면서 8, 10, 11번 시료에 대하여 500$\pm$30 years B.P, 650$\pm$30 years B.P, 800$\pm$40 years B.P의 연대측정 결과를 획득하였다. 이상과 같은 의림지 호저 퇴적층의 형성환경과 형성시기 연구를 통하여 의림지의 제방축조의 최초시기를 해석해 보면, 의림지의 제방은 적어도 과거 약 827년 전에서 866년 전에는 이미 축조되어 있었음을 알 수 있다. 과거 제천 일대에 살았던 옛사람들이 의림지 하류의 곡지중앙과 고기 충적선상지에 대한 관계용 용수조달의 필요성에 부응하여 상류부 곡지하천의 자연입지 환경을 최대한 이용하여 축조한 것으로 판단된다..준비하였다.전류를 구성하는 주요 입자의 에너지 영역(75~l13keV)에서 가장 높은(0.80) 상관계수를 기록했다. 넷째, 회복기 중에 일어나는 입자들의 유입은 자기폭풍의 지속시간을 연장시키는 경향을 보이며 큰 자기폭풍일수록 현저했다. 주상에서 관측된 이러한 특성은 서브스톰 확장기 활동이 자기폭풍의 발달과 밀접한 관계가 있음을 시사한다.se that were all low

• Journal of Wetlands Research
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• v.13 no.3
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• pp.613-621
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• 2011

Bog bean (Menyanthes trifoliata L.) is an endangered species in Korea, inhabiting in montane wetlands. Its' habitats are decreasing due to artificial disturbances and climate change in Korea. Interspecies competitions determine the distribution of a species and it is important to examine the effects of companion species on the growth of a species. To reveal the effects of habitat substrate and companion species on the growth of bog bean, we compared the growth parameters of bog bean at three substrate conditions where plant communities were formed: water column, Sphagnum mat, and paddy soil. Bog bean had the highest relative coverage at Sphagnum mat condition and there are few species whose height were higher than it. In contrast, there were many species larger than bog bean at paddy soil condition. The maximum coverage of bog bean was the largest at water column condition, and the lowest at paddy soil condition. Our results indicate that the growth of bog bean was more restricted by interspecific competition at paddy soil condition than at Sphagnum mat condition. Those results suggest that bog bean avoid competitions by expansion of rhizome rather than elongation of its height. For conservation or creation of bog bean habitats, it is necessary to offer the environment where other species cannot survive well.

• Korean Journal of Environmental Biology
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• v.24 no.4
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• pp.359-367
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• 2006

The vascular plants of this site were identified as 641 taxa through field investigation; 101 families, 340 genera, 547 species, 80 varieties, 12 forms, 1 subspecies and 1 hybrid. Based on the Rare plants of the Forest Service and Korea Forest Research Institute, 9 taxa were listed except implanted species; Loranthus tanakae, Aristolochia manshuriensis, Aristolochia contorta, Viola albida, Cypripedium macranthum, Schpolia japonioa, Acanthopanax chiisanensis, Rhododendron micranthum. Based on the Korean endemic plants, 18 taxa were listed; Salix purpurea var, japonica, Asarum sieboldii var. mandshuricum for. misnadrum, Persicaria lapathifolia for. alba, Pseudostellaria sylvatica, Aconitum pseudolaeve var. erectum, Corydalis maculata, Corydazis albipetala, Corydalis grandicazyx, Cardamine amaraeiormis, Chrysosplenium barbatum, Filipendula glaberrima, Lespedeza x tomentella, Acanthopanax chiisanensis, Melampyrum setaceum var. nakaianum, Weigela subsessilis, Adenophora triphylla var. hirsute, Cirsium setidens, Saussurea pseudogracilis. Specific plant species by floral region were total 81 taxa (12.6%); Prunus yedoensis in class V, 13 taxa (Thuja orientalis, Cimicifuga heracleiiolia, Sedum middendorffianutn, Rhododendron micranthum, etc.) in class IV, 17 taxa (Equisetum palustre, Aceriphyllum rossii, Angelica gigas, Cirsium setidens, etc.) in class III, 15 taxa (Heloniopsis orientalis, Lychnis cognata, Saxifraga oblongifolia, Viola orientalis, etc.) in class II, 35 taxa (Hosta capitata, Cimicifuga simplex, Chrysosplenium flagelliferum, Campanula punctata, etc.) in class I. So, the naturalized plants were listed 53 taxa and the naturalization index was 8.2%, urbanization index was 20.7%.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.12 no.4
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• pp.47-71
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• 2009

The resource plants of northern region in Gapyeong-gun were investigated 7 times from Apr. 2007 to Oct. 2007. In the result of survey, the flora of this area, depend on voucher specimens, consist of 480 taxa totally; 94 families, 286 genera, 412 species, 4 subspecies, 52 varieties and 12 forms. The Resource plants in this area were categorized by their use into edible 177, pasturing 136, medicinal 124, stainable 69, ornamental 133, afforest 24, timber 10, fiber 6, industrial 2 taxa and unknown use plants 72, respectively. There were remarkable plants such as 14 taxa of Korean endemic plants, 85 taxa of specific plants which were designated by the Ministry of Environment, and 12 taxa of rare and endangered plants of Korea Forest Service. Furthermore, 22 taxa of naturalized plants 4.6% were also observed in this area and Urban Index (UI) was 8.2%. The vegetation status of investigated area was comparatively well conserved, but the degree of UI could be increased rapidly by the climbers, development of forest road. Therefore, the systems for conservation need to prepared for the effective management of forest, and the special plans need to control the number of climbers and visitors.

• Journal of the Korean Institute of Landscape Architecture
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• v.49 no.2
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• pp.101-112
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• 2021

In Korea, efforts have been made continuously to improve the environment of traditional markets concerning the issues of urban regeneration. In particular, many old cities and traditional markets face a lack of parking spaces. As a solution to this, attempts are being made to prepare underground parking spaces by designing urban planning facilities in three-dimensional ways and utilizing the upper part as a more meaningful space. This study is about the master plan to use the upper green area while creating an underground parking lot at 571 Sinmae-dong, Suseong-gu, Daegu. This green area was defined as a space with dual values, 'defensive green space' that needs to be ecologically protected, and 'active cultural space' where walking flows to the market and various events are concentrated. Three specific design strategies to balance these values were presented. First, to prevent indiscriminate occupation and damage by people and maintain a healthy green environment, securing the maximum amount of undivided green space in the site was suggested. Second, a space layout and a topography and planting patterns that can overcome the morphological characteristics of narrow and long-shaped sites enable the experience of abundant green spaces. Third, providing space to strengthen the connections with nearby urban facilities such as Sinmae Market and Gosan Library can also intensively accommodate cultural activities in various cities. This study has academic significance in providing implications for urban regeneration projects with similar contexts in the future.

• Ecology and Resilient Infrastructure
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• v.7 no.4
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• pp.366-373
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• 2020

This study investigated habitat diversity changes by conducting weir operations at the Sejongbo site in the Geum River basin. High-resolution aerial photographs taken before and after the weir-opening operation were used for habitat analyses. We classified water and bar areas into 17 types, such as lotic habitats, including riffles, runs, and glides, and lentic habitats, including reservoirs, pools, bar-head backwaters, and bar ponds. Then, we estimated each habitat area quantitatively, calculated a habitat diversity index, and established a habitat diversity map. Our results indicated that after the weir-opening operation, lotic habitats and new types of shallow lentic habitats increased in the water area. In addition, for the bar area, bare lands without cultivation increased distinctively. Finally, we observed that the habitat diversity index drastically increased after the weir-opening operation, which could provide a relatively simple channel of diverse habitats.

• Korean Journal of Remote Sensing
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• v.38 no.3
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• pp.225-236
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• 2022

Urbanization due to population growth and regional development can cause various environmental problems, such as the urban heat island phenomenon. A planned city is considered an appropriate study site to analyze changes in urban climate caused by rapid urbanization in a short-term period. In this study, changes in land cover and surface heat island phenomenon were analyzed according to the development plan in Sejong City from 2013 to 2020 using Landsat-8 Operational Land Imager/Thermal Infrared Sensor (OLI/TIRS) satellite imagery. The surface temperature was calculated in consideration of the thermal infrared band value provided by the satellite image and the emissivity, and based on this the surface heat island effect intensity and Urban Thermal Field Variance Index (UTFVI) change analysis were performed. The level-2 land cover map provided by the Ministry of Environment was used to confirm the change in land cover as the development progressed and the difference in the surface heat island intensity by each land cover. As a result of the analysis, it was confirmed that the urbanized area increased by 15% and the vegetation decreased by more than 28%. Expansion and intensification of the heat island phenomenon due to urban development were observed, and it was confirmed that the ecological level of the area where the heat island phenomenon occurred was very low. Therefore, It can suggest the need for a policy to improve the residential environment according to the quantitative change of the thermal environment due to rapid urbanization.

• Korean Journal of Remote Sensing
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• v.38 no.3
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• pp.311-326
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• 2022

The Compact Advanced Satellite 500-4 (CAS500-4) is under development to efficiently manage and monitor forests in Korea and is scheduled to launch in 2025. The National Institute of Forest Science is developing 36 types of forestry applications to utilize the CAS500-4 efficiently. The products derived using the remote sensing method require validation with ground reference data, and the quality monitoring results for the products must be continuously reported. Due to it being the first time developing the national forestry satellite, there is no official calibration and validation site for forestry products in Korea. Accordingly, the author designed a calibration and validation site for the forestry products following international standards. In addition, to install calibration and validation sites nationwide, the authors selected appropriate sensors and evaluated the applicability of the sensors. As a result, the difference between the ground observation data and the Sentinel-2 image was observed to be within ±5%, confirming that the sensor could be used for nationwide expansion.

• Journal of Korean Society of Forest Science
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• v.113 no.1
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• pp.14-30
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• 2024

This study characterized areas at risk of land creep by focusing on a site that has undergone this phenomenon in Ulju-gun, South Korea. Land creep in the area of interest was catalyzed by road expansion work conducted in 2022. The site was examined on the basis of its geological features, topography, effective soil depth, soil hardness, electrical resistivity, and subsurface profile. It consists of a slope covered with sparse vegetation and a concave top that retains rainwater during rainfall. Compositionally, land creep affected the shale, sandstone, and conglomerate formations on the site, which had little silt and more sand and clay compared with areas that were unaffected by land creep. An electrical resistivity survey enabled us to detect a groundwater zone at the site, which explains the softness of the soil. Finally, the effective soil depth at the land creep-affected area was 30.4 cm on average, indicating deep colluvial deposits. In contrast, unaffected sites had an effective soil depth of 24.7 cm on average. These results should facilitate the creation of systems for monitoring and preemptively responding to land creep, significantly mitigating the socioeconomic losses associated with this phenomenon.

• Korean Journal of Environmental Biology
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• v.24 no.3
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• pp.248-257
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• 2006

Total naturalized plant species in the streams of Jeonju were listed as 109 taxa; 24 families, 75 genera, 106 species, 3 varieties. Dividing by stream, Jeonju stream has 75 taxa; 20 families, 55 genera, 73 species, 2 varieties. Samcheon stream has 86 taxa; 19 families, 64 genera, 84 species, 2 varieties. Soyang stream has 80 taxa; 21 families, 60 genera, 77 species, 3 varieties. Urbanization Index (UI) of total streams (109 taxa) was 40.2%. UI was 27.7% in Jeonju stream (75 taxa), 31.7% in Samcheon stream (86 taxa), 29.5% in Soyang stream (80 taxa). Dividing by degree of naturalization classification, 25 taxa (9.2%) were found in class 5, 17 taxa (6.2%) in class 4, 32 taxa (11.8%) in class 3, 27 taxa (9.9%) in class 2 and 8 taxa (2.9%) in class 1. Dividing by introduction period, 48 taxa (44%) aye in period I, 19 taxa (17%) in period II, 42 taxa (39%) in period III. Dividing by growth type, 48 taxa (44%) are annuals, 25 taxa (23%) are biennials, 33 taxa (30%) are perennials. Dividing by the place of origin, 39 taxa (35%) are from Euyope, 33 taxa (30%) from North America, 11 taxa (10%) from Tropic America, 9 taxa (8%) from Europe Asia,5 taxa (5%) from South America, 5 taxa (5%) from China.