• Nuclear Engineering and Technology
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• v.37 no.3
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• pp.259-264
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• 2005

This paper presents a vital area identification (VAI) method based on the current fault tree analysis (FTA) and probabilistic safety assessment (PSA) techniques for the physical protection of nuclear power plants. A structured framework of a top event prevention set analysis (TEPA) application to the VAI of nuclear power plants is also delineated. One of the important processes for physical protection in a nuclear power plant is VAI that is a process for identifying areas containing nuclear materials, structures, systems or components (SSCs) to be protected from sabotage, which could directly or indirectly lead to core damage and unacceptable radiological consequences. A software VIP (Vital area Identification Package based on the PSA method) is being developed by KAERI for the VAI of nuclear power plants. Furthermore, the KAERI fault tree solver FTREX (Fault Tree Reliability Evaluation eXpert) is specialized for the VIP to generate the candidates of the vital areas. FTREX can generate numerous MCSs for a huge fault tree with the lowest truncation limit and all possible prevention sets.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.2
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• pp.59-71
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• 2019

This study was conducted to prioritize land purchase in Hwapocheon wetland protection area by reflecting the conservation value of wetlands considering HSI(Habitat Suitability Index) for flagship species. As a result of this study, the flagship species, Oriental White Stork and Been Goose, which can represent the Hwapocheon wetland protection area, were selected through selection criteria and expert feedback. Based on the habitat requirements of the selected flagship species, SI(Suitability Index) for the flagship species was reviewed and the conservation value of wetlands was assessed. The conservation value of the wetlands was divided into five grades from very high to very low. The areas with high conservation value were mainly distributed around wetlands and waters in upstream and downstream of Hwapocheon wetland protection area. The land purchase priorities were divided into five grades by overlapping the thematic maps of the conservation value of wetlands, the economics, and the urgency of restoration. The arable lands which can disrupt wetland ecosystems are analyzed as priority areas where priority purchasing is required. Relatively well-preserved wetlands and areas have low land purchase priorities. This study is meaningful in that biodiversity is considered in land purchase priorities.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.24 no.3
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• pp.99-114
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• 2021

We examined a current status of damage in biodiversity and its causing factors in Hasidong Anin coastal dune, Gangneung-si, Gangwon province which is designated as ecological and landscape conservation area. In this study, we found that ecosystem and biodiversity have been primarily damaged by anthropogenic factors such as the construction of surrounding area, military facilities illegally dumped garbage and the expansion of windbreak forest. These factors occur to damage the landscape, ecosystem and biodiversity etc. There is a significant lack of basic data needed for preservation and restoration due to the lack of prior research and value assessment. In order to establish solutions for preservation and restoration, it is critical to collect fundamental data and implement value assessments. Therefore, further studies such as ecosystem services assessment, increasing biodiversity, spatial analysis and monitoring of various items related to coastal dunes are needed.

• Journal of Korean Society of Forest Science
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• v.80 no.4
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• pp.369-378
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• 1991

Major statutory nature protection areas include Nature Parks, Nature Reserves. Nature Ecological System Protected Areas. Biosphere Reserves, Nature Protected Forests, Wildlife Sanctuaries, and Protection Forests with total area of 1,124,000 ha. These protected areas cover almost 18% of the forested area. The number of visitors of NPs reached over 33 million per year with sharp increasing rate over the years. To protect the deteriorated hiking trails and camp grounds caused by overuse, two management policies have been implemented : cooking prohibition and natural rest rotation system. While prohibition of cooking is based on the fact that most of the solid wastes in nature parks are leftovers of cooking, natural rest rotation system is mainly for rehabilitation of deteriorated areas by natural processes. The system has closed 47 trails(in 27 mountains) throughout the country since January 1991, which is scheduled to continue 3 years. Due to the lack of accumulated scientific knowledge on how, when and where to close, application of the system leaves much to be desired. This paper discusses the current efforts to protect the natural resources for recreational use and suggests future directions for an effective policy implementation.

• Journal of Bio-Environment Control
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• v.22 no.2
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• pp.162-166
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• 2013

The objective of this study was to investigate the influence of fertilization levels by soil testing on plant growth and fruit quality of musk melon in greenhouse cultivation. Leaf area and fruit weight were severely affected by fertilization level. Leaf areas were significantly reduced by 54.1% and 24.5% at 0 and 50% fertilization level compared to the 100% fertilization level, respectively. Fruit weights were reduced by 38.2% and 19.9% at 0 and 50% fertilization level compared to the 100% fertilization level, respectively. However, soluble solids and sucrose contents were increased by 1.8% and 23.3% at 50% fertilization level compared to the 100% fertilization level, respectively. These results suggest that reduction of 50% fertilization level by soil testing seem to be effective methods to reduce salt accumulation in the soil as well as increasing of fruit quality such as soluble solids and sucrose contents.

• Journal of Bio-Environment Control
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• v.7 no.1
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• pp.25-33
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• 1998

Root zone temperature have influenced on protected cultivation in winter season. Especially root zone temperature is acted on limiting factor in crop cultivation. This study was conducted to obtain optimum temperature of root zone in Protected cultivation Root zone was warmed by heated water($28^{\circ}C$) flowing through the PPC pipe(${\phi}15$) buried depth 40 cm. And the flowing water was heated by solar system. Minimum air temperature during night time was set at $14^{\circ}C$ and maximum air temperature during day time was set at $28~30^{\circ}C$ the growing period of cucumber was from Nov. 6, 1996 to Jan. 30, 1997. The results are summarized as follows. 1. Average soil temperature at 15~20 cm depth was $22^{\circ}C$ at warming plots, $17~18^{\circ}C$ at non-warming plots 2. Early growth in leaf length, stem diameter, number of leaves and leaf area for 30 days after planting were accelerated by root zone warming. Especially, the grawing rate of soil warming plots was higher 27% in leaf length, 51% in leaf number, 150% in leaf area than non-warming Plots. Above-ground and underground part of warming plots was higher 117%, 56% than non-warming plots. 3. In total yield analysis, number of fruits were 614 in soil warming and 313 in non-warming plots. In the result, total yield of soil warming plots was increased with 196% than non-warming plots. 3. In total yield analysis. number of fruits were 614 in soil warming and 313 in non-warming plots. In the result. total yield of soil warming plots was increased with 196% than non-warming plots.

• Korean Journal of Environment and Ecology
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• v.6 no.1
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• pp.12-24
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• 1992

The application of island biogepgraphy and habitat fragmentation theory to protected area management in Korea is discussed. The accelerating destruction and degradation of natural habitats, with the associated erosion of biodiversity, demands and urgent response and a critical review of attitudes to protected area management. The flora of Korea will continue to change in both distribution and status in response to these man induced changes. The conservation and management of ecosystems, because of the variety of threats and the varying levels of biodiversity to be conserved, requires an integrated approach. Such an approach assesses the variety of threats, prevalent and potential, and responds with a strategy combining habitat, species and population management. The application of island biogeography, habitat fragmentation and edge effects theory to conservation strategies in Korea will assist in the understanding of the dynamic relationships between the isolation. degradation and fragmentation of surviving habitat patches. The application of such approaches is discussed with recommendations made for the adoption of an increasingly scientific approach to plant conservation based upon a knowledge of the conservation status and distribution characteristics of the Korean flora. Such data combined with demographic studies on topics such as Minimum Viable Population Size will allow an integrated approach to plant and habitat conservation to progress.

• Journal of Wetlands Research
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• v.19 no.4
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• pp.403-408
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• 2017

This study aims to set up the basic data to manage the waterfowl habitat through the analysis of the changes of physical structure according to the time series of Hangang(Riv.) as water birds' habitat. Study area was 41.5km in length from Paldang bridge to Hangju bridge. during total length of 497.52km and horizontal boundary was based on the protected lowland in year 1975. As the analysis result of land use from the center of water to adjacent road to the river, ratio of year 1975 was in order of sedimentary land(22.7%), surface water(20.7%), built-up area(16.9%), field(16.2%), paddy field(15.9%), and afterwards most of the areas were changed through the construction of arterial highway and submerged weir in order to use Hangang(Riv.). In year 1985, the area ratio of protected lowland(57.8%) and surface water(32.8%) dramatically increased. After construction of river bank the recreational areas continually increased and relatively natural areas decreased. In year 2005, the area ratio of protected lowland was enlarged to 57.6% and surface water also to 33.3%. While the length of both riversides and naturalness decreased by 10.9%, 91.5% respectively in year 2005 compared to year 1975, the depth of water increased by 1.46m. Comprehensively, the flow of changes by physical structure in Hangang(Riv.) for 30 years was divided into two periods. The main characteristics in the first period were decrease of riverside area and enlargement of the surface water through the massive construction before middle of year 1980, and afterwards revetments were intensively artificialized with changes of land use for amusement area. In terms of water fowl habitat, Hangang(Riv.) which previously had various types of habitat condition was changed into simplified habitat for few of species, and the active improvement apporach was needed for habitat diversity.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.6
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• pp.167-185
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• 2020

The purpose of this study is to prepare a plan for improving the bird habitat environment of Linear Park. To this end, after grasping the status of bird habitats on the Gyeongchun Line Forest Road, a representative linear park in Seoul, the habitat environment was evaluated and the correlation with the bird habitat was analyzed to derive a plan to improve the habitat environment. The results for correlation between diversity of birds and habitat environment were as follows. For the habitat environment inside the park, the order of positive correlation was in the order of park area (0.92), number of insect species (0.87), green area ratio (0.77), average width of linear park (0.74), Biotope area ratio (0.73), Immigration planted species (0.57). Also, for habitat environment outside the park, the bird diversity was influenced in the order of area outside the park (0.88), green area ratio of the park (0.76). Thus, in order to enhance the diversity of birds found in the park, the bird habitat environment inside the park needs to expand the park area, secure insect diversity, enhance green area ratio and ecological area ratio, expand the width of linear park, and lower the impermeable layer. For the bird habitat environment outside the park, wider area, green area ratio, and forest area of the park influenced on better bird habitation while lower ratio of road space and building-to-land ratio influenced on higher bird diversity. It is necessary to create an environment inhabitable for various species of birds and to make a healthy and pleasant city urban system for co-existence of human and living creatures.

• Journal of Bio-Environment Control
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• v.19 no.1
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• pp.6-11
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• 2010

This experiment was conducted to investigate the effect of greenhouse orientation on the greenhouse environment and the growth and yield of tomato cv 'Momotaro-Yoku' in forcing culture. The photosynthetic phpton flux density (PPFD) of a.m was higher in north-south orientation than that in east-west orientation and it was opposed in the p.m. Mean PPFD of a day was higher in east-west orientation than that in north-south orientation because the light transmitting area became larger in east-west orientation with decrease of incidence angle. The PPFD at 60 cm point above ground of all furrows was poor due to shadows near plants and it was higher in north-south orientation than that in east-west orientation. The air temperature in the greenhouse was higher in east-west orientation than that in north-south orientation but there was no significant difference since mid February as solar altitude goes up. The soil temperature was some higher in east-west orientation than that in north-south orientation and there was not significant difference among ridges. In east-west orientation, as ripening was promoted, high early yield of tomato were obtained. So total yield was greater about 8% in east-west orientation than that in north-south orientation. Therefore, it was considered that east-west orientation is more advantageous than north-south orientation for forcing culture of tomato.