• The Journal of Advanced Prosthodontics
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• v.8 no.6
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• pp.494-503
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• 2016

PURPOSE. The aim of this study was to compare the efficacies of two-implant splinting (2-IS) and single-implant restoration (1-IR) in the first and second molar regions over a mean functional loading period (FLP) of 40 months, and to propose the appropriate clinical considerations for the splinting technique. MATERIALS AND METHODS. The following clinical factors were examined in the 1-IR and 2-IS groups based on the total hospital records of the patients: sex, mean age, implant location, FLP, bone grafting, clinical crown-implant ratio, crown height space, and horizontal distance. The mechanical complications [i.e., screw loosening (SL), screw fracture, crown fracture, and repeated SL] and biological complications [i.e., peri-implant mucositis (PM) and peri-implantitis (PI)] were also evaluated for each patient. In analysis of two groups, the chi-square test and Student's t-test were used to identify the relationship between clinical factors and complication rates. The optimal cutoff value for the FLP based on complications was evaluated using receiver operating characteristics analysis. RESULTS. In total, 234 patients with 408 implants that had been placed during 2005 - 2014 were investigated. The incident rates of SL (P<.001), PM (P=.002), and PI (P=.046) differed significantly between the 1-IR and 2-IS groups. The FLP was the only meaningful clinical factor for mechanical and biological complication rates in 2-IS. CONCLUSION. The mechanical complication rates were lower for 2-IS than for 1-IR, while the biological complication rates were higher for 2-IS. FLP of 39.80 and 46.57 months were the reference follow-up periods for preventing biological and mechanical complications, respectively.

• The KIPS Transactions:PartC
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• v.11C no.5
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• pp.653-658
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• 2004

Failures in optical networks that have huge transmission capability provoke service discontinuitH and thus large economical damage. Even though many algorithms are proposed for protection and restoration on a single failure, there are few algorithms for multiple failures. Eulerian tour is known to be effective to protect and restore a single failure in the literature. This paper proposes an algorithm that can perform efficient protection and restoration for multiple failures based on combined Eulerian tours. The proposed one is very effective on protection and restoration in general cases with two failures, and the comprehensive computer simulation shows that the restoration rate increases up to about 90%.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.1
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• pp.109-130
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• 2013

This study is to offer the raw data for conservation and restoration of national park by surveying and analysing the vascular plants in the Gayasan national park. The flora were summarized as 102 families, 328 genera, 469 species, 4 subspecies, 59 varieties and 9 forms. The endangered plants designated by Ministry of Environment were 2 taxa; Pedicularis hallaisanensis Hurus. and Gymnadenia conopsea for. albiflora Y.N.Lee. The rare plants designated by Korea Forest Service were 13 taxa; Crypsinus hastatus (Thunb.) Copel., Ligusticum tachiroei (Franch. & Sav.) M. Hiroe & Constance, Primula modesta var. fauriae (Franch.) Takeda, Lilium distichum Nakai ex Kamibay and so forth. The korean endemic plants were 15 taxa; Betula ermanii Cham., Carpinus laxiflora (Siebold & Zucc.) Blume, Stewartia pseudocamellia Maxim., Galium koreanum (Nakai) Nakai, Heloniopsis koreana Fuse, N.S. Lee & M.N. Tamura and so forth. The specific plants by floristic region were 66 taxa; Betula chinensis Maxim., Spiraea fritschiana Schneid., Vaccinium hirtum var. koreanum (Nakai) Kitam., Cimicifuga heracleifolia Kom., Adoxa moschatellina L. and so forth. The plants with approval for delivering oversea were 22 taxa; Salix hallaisanensis H.L$\acute{e}$v., Sanguisorba argutidens Nakai, Viola albida Palib., Weigela subsessilis (Nakai) L.H.Bailey and so forth. The naturalized plants were 30 taxa; Chenopodium album L., Lepidium apetalum Willd., Trifolium pratense L., Bidens frondosa L., Helianthus tuberosus L. and so forth.

• Proceedings of the Korean Quaternary Association Conference
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• 2002.12a
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• pp.94-95
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• 2002

South Korea is divided into five ecoprovinces and sixteen ecoregions. The criteria for ecoprovince classification are ecosystem connectivity and cultural homogeneity. Ecoregions are classified by cluster analysis. The variables used in the analysis are latitude, longitude, seasonal mean temperature, and seasonal precipitation. The large forest fires occurred in the specific ecoregions including Kangwon coastal ecoregion, WoolYoung coastal ecoregion, Hyungsan Taehwa coastal ecoregion, Upper Nagdong river basin ecoregion and Southeastern inland ecoregion. The largest forest fire in the korean history occurred in Kangwon coastal ecoregion in the year 2000. The fire devastated the forestland over 25,000ha. Korea Forest Service, Ministry of Environment, Province Kangwon and NGO organized an investigation committee for the restoration of the burnt area. The committee suggested restoration principles and also forged a restoration strategy of the Kangwon burnt area.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.11-11
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• 2020

Background : The genus Cypripediums are typically adapted to the low temperature and cold climates of the high land in Korea. The species which were reported in Korean peninsula are C.japonicum, C.macranthos, C.calceolus and C.guttatum. We had already reported the successful germination of the C.macranthos and C.guttatum. The small spotted lady's slipper orchid(C.guttatum) is most endangered plants to extinction of which population was reported less than 100 in Korea. The objective of the present research is restoration of the C.guttatum in ex situ and adaptation in high land and nursery. Methods and Results : The 350 seedlings of C.guttatum were transplanted in soil at alpine area(altitude 750m) and the nursery of Korea National Arboretum(KNA) in YangPyeong city on May 2019 and 2020 in order to verify the possibility of ex situ restoration. The sprouted ratio of the seedlings were less than 10% in the alpine area and 83% in the nursery of KNA. The reasons of the diverse survival ratio are presumed as the low moisture content in the soil and heavy shade of the alpine area. The 15 cypripedium species and 29 hybrids were also effectively adapted in the KNA rare plant garden. Conclusion : These results demonstrated the difficulties of the restoration for small spotted lady's slipper orchid in the natural habitation. From the above results, we may conclude that the critical factors of the genus Cypripedium are intensive care for the fragile seedlings during the 1^st year acclimatization.

• Korean Journal of Environment and Ecology
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• v.28 no.6
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• pp.650-656
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• 2014

This study was executed in Woraksan National Park from Febuary, 2008 to December, 2013 in order to study the behavioral characteristics of introduced four female gorals using annual home range, seasonal home range, and elevation use characteristics. Annual home range of reintroduced female gorals were $1.13{\pm}0.32km^2$ of MCP 95%, $0.37{\pm}0.18km^2$ of MCP 95% and $0.07{\pm}0.03km^2$(t=0.607, p>0.05) of FK 50% respectively. In seasonal home range and elevation use characteristics of MCP 95%, autumn($0.73{\pm}0.26km^2$) and summer($0.77{\pm}0.06km^2$) were the largest home range and spring($0.58{\pm}0.38km^2$) and winter($0.47{\pm}0.25km^2$) had a smaller home range and it showed that there was a difference between summer and winter home ranges(F=3.868, P<0.05). As a result of seasonal elevation analysis, elevation use was 435m(28.4%) in spring, 464m(26.7%) in summer, 414m(28.8%) in autumn, and 393m(21.2%) in winter, respectively. It showed that these gorals used higher elevation in summer(F=0.783, P>0.05). We could not analyze the characteristics of introduced gorals, because only introduced female gorals were used for this study. However, we could understand that habitat use characteristics were of statistical significance in introduced gorals from the analyses of their home range, seasonal home range and elevation use.

• Korean Journal of Environment and Ecology
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• v.21 no.4
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• pp.347-355
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• 2007

Asiatic black Bear(Ursus thibetanus ussuricus) cubs aged one or two were introduced from Russia(Primosky krai) and North Korea for reinforcement of the bear population and they were released to grow wild in Jirisan National Park. We did research on the characteristics of the denning sites of the Asiatic black cubs, which were released before, from Oct. 2004 to Apr. 2006, and the results were as follows: The released bears hibernated in three types of dens,; tree hollows, rock hollows or ground nests. The hibernating sites were dominated by a community of oak trees and its location was at an average of $923{\pm}221m$ height above the sea level ; the average slope incline was $25.9{\pm}7.9^{\circ}$, and the average denning duration was $98{\pm}9$ days. It was analyzed that the cubs' denning site was $2.8{\pm}2.8km$, on an average, far from the release point; $2.0{\pm}0.9km$ far from villages; $1.9{\pm}1.7km$ far from park inspection trails, and $1.9{\pm}1.0km$ on the average far from a driveway. It is assumed that environmental attributes of the denning sites were closely correlated to those of the release points.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.25 no.6
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• pp.13-24
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• 2022

The purpose of this study is to evaluate the applicability of Ecosystem Service Matrix method in Songnisan and Hannamgeumbukjeongmaek Boeun-gun area. The assessment was carried out with 25 land cover types by 7 ecosystem values. The research area was divided by 30m x 30m cell unit and the each cell value was classified into 5 grades. The total number of cell under the investigation was 433,910 units in Songnisan and 84,975 in Boeun-gun. Class I and II area were widely spread and Class V area is narrowly distributed inside of Class III area in Songnisan. I area, II area and separately managed zone belong to Ecological Zoning map and Environmental Conservation Value Assessment Map(Environment + Ecology) were assessed Class I in Ecosystem service matrix. In conclusion, Ecosystem Service Matrix assessment based on land cover map is a rapid assessment methodology which reflecting ecosystem functions in a larger area. If it is supported with more ecosystem functions, the more precise nature value can be calculated.

• Journal of Korean Society on Water Environment
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• v.32 no.1
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• pp.15-22
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• 2016

This study aims to analyze the changes in the benthic macroinvertebrate community before and after a restoration project in a eutrophic stream. Species diversity and species richness increased at the points where the channel changed from standing water to running water. However, species diversity and richness decreased at the points where only riparian restoration was implemented, and the concentration of suspended solids increased, while biochemical oxygen demand and total phosphorus decreased and the concentration of dissolved oxygen increased. In such reaches, functional feeding groups went from collector-filterers to collector-gatherers, and habitat orientation groups changed from clingers to burrowers.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.12
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• pp.94-105
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• 2003

OBS(Optical Burst Switching) networks which decouple the burst from its header has characteristic one-way reservation. Therefore, the fault of a fiber link may lead to the magnitude of burst loss. Since sending a header packet and using an offset time before the transmission of the corresponding burst. In this paper, we analysis a offset time based on the burst loss rate resulting from only link failure and by applying the restoration schemes in an optical burst switching networks. The simulation results in terms of the effect of a offset time is evaluated in our network model to verify that comparing the numerical analysis with simulation result. Finally, and through these results, We propose the new restoration scheme based on offset time considered Quality of Service.