• Journal of Forest and Environmental Science
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• 제31권3호
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• pp.149-163
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• 2015

The aim of the present study was to assess the variation in species composition and diversity of woody species at different altitudes (900 to 2600 m asl) in Kedarnath Wildlife Sanctuary (KWLS) and its adjoining areas in Garhwal Himalaya, India. A total of 94 woody plant species (including 44 tree and 50 shrub species) belonging to 72 genera and 44 families were reported. Density varied from $235{\pm}9$ to $505{\pm}21trees\;ha^{-1}$ and $4,730{\pm}474$ to $9,530{\pm}700shrubs\;ha^{-1}$. Total basal cover varied from $10.49{\pm}0.66$ to $42.92{\pm}2.57m^2ha^{-1}$ (trees) and $0.36{\pm}0.024$ to $0.62{\pm}0.047m^2ha^{-1}$ (shrubs). Shannon-Wiener Index fluctuated between 2.30 to 3.53 (trees) and 2.74 to 3.78 (shrubs). Analysis of variance (ANOVA) indicated that altitude and aspect had significant effect on the distribution of woody species. Taxonomically, Rosaceae with 15 species emerged as the dominant family. Low value of maturity index and contiguous distribution of species denoted the early successional status of the studied forests. The conservation assessment based on altitudinal regimes and the information on species structure and function can provide baseline information for monitoring and sustaining the biodiversity.

• Plant Resources
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• 제4권3호
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• pp.130-139
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• 2001

Four major naturally populated areas around the Jindong valley in Inje-Gun, Gangwon province for wild Pyrus ussuriensis, Malus sieboldii, and Malus baccata are mostly located on the southeast side of the mountains at 630-745m in altitude at sea level and are in very good sunny areas. The total of 77 taxa dividing into 32 families, 58 genera, 65 species, and 12 varieties has been inhabited in these areas. Most of these plants are heliophytes, which love sunshine, but some of rhizo-plants such as Sasa borealis, climbing plants such as Actinidia arguta and Celastrus orbiculatus, or naturalized plants like Bidens frondosa are also shown. These areas have been continually destroyed, so it is possibly thought that the second transition has been progressed. The index of species diversity of plant groups in these areas is 0.672∼1.465 based on the Shannon-Wiener's method, but its index for the area that rhizo-plants like Sasa borealis are growing as an under planting decreases relatively. In this study, the oldest plant of Pyrus ussuriensis in Korea, which is 120cm in diameter at breast height (DBH), 19m in tree height and 25m in width, has been found.

• 한국수산과학회지
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• 제38권6호
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• pp.385-392
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• 2005

Seasonal variation of abundance and species composition of ichthyoplankton were studied in the coastal water off Tongyoung, Korea. Monthly samples were collected using a ring net which were towed horizontally at 4 different stations from March, 1998 to February, 1999. A total of 74 species representing 35 families and 8 orders were found. Of these species 40 species (17 families) were Perciformes. Of the fish larvae couected Engraulis japonicus, Repomucenus sp., Parablennius yatabei, Synechogobius hasta, and Tridentiger sp. were the dominant species representing $80.6\%$ in total number of individuals. The number of species was highest in August and lowest in December; number of individuals was highest in May and lowest in November. The diversity index (Shannon and Wiener Index) was highest in march, and lowest in December.

• 한국환경과학회지
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• 제12권1호
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• pp.15-22
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• 2003

Fifteen major naturally populated habitats around the Mt. Halla, Jeju province for wild Cornus kousa are mostly located on the southeast side of the mountains at 850-1,550m in altitude at sea level and are in half sunney areas. More than 40.0% of the naturally populated area of Cornus kousa are edge of forest areas and 53.3% populate on the steep slope of the mountain in 0-5℃. The direction of the slop for about 40.0% of total populated areas is southeast. In the naturally populated areas, total of 64 taxa dividing into 42 families, 59 genera 56 species and 8 varieties have been shown, mostly Hydrangea petiolaris, Rubus oldhamii, Ilex crenata, Sasa quelpaertensis, Ligustrum obtusifolium. It is suggested that these areas are secondary forest in a typical deciduous forest in Mt. Halla where the second transition had been progressed after forest damage or environmental stress. The index of species diversity of plant groups in these areas is 1.286-4.238 based on the Shannon-Wiener's method.

• Structural Monitoring and Maintenance
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• 제2권3호
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• pp.237-252
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• 2015

This paper addresses the issue of reliability and performance in wireless sensor networks (WSN) based structural health monitoring (SHM), particularly with decentralized damage identification techniques. Two decentralized damage identification algorithms, namely, the autoregressive (AR) model based damage index and the Wiener filter method are developed for structural damage detection. The ambient and impact testing have been carried out on the steel beam structure in the laboratory. Seven wireless sensors are installed evenly along the steel beam and seven wired sensor are also installed on the beam to monitor the dynamic responses as comparison. The results showed that wireless measurements performed very much similar to wired measurements in detecting and localizing damages in the steel beam. Therefore, apart from the usual advantages of cost effectiveness, manageability, modularity etc., wireless sensors can be considered a possible substitute for wired sensors in SHM systems.

• Journal of Forest and Environmental Science
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• 제34권1호
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• pp.31-45
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• 2018

At present the biodiversity of the riparian forest is under threat due to various anthropogenic pressures. Hence study was conducted along the three unprotected zones of riparian forest in Dikhu river, Nagaland, north-east India in order to compared the diversity, distribution and population structure of riparian trees. In each zone $100{\times}100m^2$ plot were marked and subdivided into 20 plots of $10{\times}10m^2$. 10 plots on each side of the river were taken randomly covering 0.02 ha. Only tree with dbh ${\geq}10cm$ and dbh above 1.5 m above ground level were recorded as individual species. A total of 29 tree species belonging to 18 families were recorded from the three zones of the river. Tree species richness was highest at the middle zone (19) followed by upper (14) and lower zone (7). The most abundant species and family recorded at upper, middle and lower zones were Melia azaderach of Euphorbiaceae ($380\;stems\;ha^{-1}$), Terminalia chebula of Euphorbiaceae ($432.5\;stems\;ha^{-1}$) and Duabanga grandiflora of Lythraceae ($365\;stems\;ha^{-1}$) respectively. The ranges of diversity indices observed in the three zones were: Shannon-Wiener index (1.25-0.73), Simpson diversity index (0.42-0.93), Evenness index (0.47-0.37) and Index of co-dominance (0.75-0.94). Rest of other indices were also estimated and compared. Distribution of trees shows the contagious pattern common in the upper and middle zones and regular in the lower zone. The girth size class analysis demonstrated that the riparian forest is in less mature succession stage. This study emphasize the need for management and conservation of riparian forest by developing policy to declare the riparian zone as protected area to prevent further degradation and loss of biodiversity from these unregulated zones along the river.

• 한국산림과학회지
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• 제103권3호
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• pp.313-320
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• 2014

본 연구는 경상북도 봉화군 석포면 대현리와 소천면의 경계에 있는 청옥산 산림습원의 현황을 파악하고 습원의 식물상 및 식생조사를 통해 생물종다양성을 확보하여 산림 생태계의 보전 및 관리를 위한 기초 자료를 제공하기 위하여 수행되었다. 조사대상지에 분포하는 자원식물의 종류조성은 72과 167속 209종 2아종 27변종 5품종 총 243종류로 밝혀졌다. 한국특산식물은 7과 9속 9종 총 9종류가 출현하였으며, 희귀식물은 11과 13속 12종 3변종 총 15종류가 출현하였고, 귀화식물은 5과 8속 8종 총 8종류가 분포하였다. 습지출현빈도에 따른 구분은 절대육상식물이 184종(75.72%)으로 가장 많이 나타났고 절대습지식물은 4종(4.65%)이 확인되었다. 습한 정도에 따른 구분은 습생식물이 26종류, 정수식물이 2종류 확인되었다. 생육지에 따른 구분은 숲이 136종류(55.97%)로 가장 많이 나타났고, 개방지가 70종류(28.81%), 습한 개방지가 35종류(14.40%), 수중이 2종류(0.82%)가 확인되었다. 본 조사지역의 식생구조를 중요치와 종다양성지수로 분석한 결과 목본식물 중에서는 물푸레나무의 중요치가 22.17%로 가장 높게 나타났으며, 초본식물 중에서는 햇사초가 10.40%로 가장 높은 수치를 나타냈다. 이 지역의 평균 종다양성지수는 2.507로 비교적 높은 것으로 나타났다. 본 연구의 결과에 기초하여 생태적인 복원 및 복구을 위해서 장기적인 모니터링이 필요할 것으로 판단된다.

• 미생물학회지
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• 제46권3호
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• pp.262-269
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• 2010

국내 자생하는 왕대, 분죽, 조릿대, 호마죽과 같은 다양한 대나무 산림토양의 낙엽층, 부식층, 근권토양 내 방선균 밀도 측정 결과, $2.7{\times}10^6-2.7{\times}10^8$ CFU/g로 계수되었으며, 특히 조릿대 낙엽층 내에는 $2.7{\times}10^8$ CFU/g의 매우 높은 밀도로 분포하였다. 본 연구에서는 대나무림 낙엽층으로부터 100균주, 부식층으로부터 70균주 그리고 근권토양으로부터 160균주로 총 330균주의 방선균을 수집하였다. 이들 분리된 균주들의 기균사, 기중균사 및 색소형성 등을 관찰한 결과 36개 방선균 군집으로 분류되었다. 각 그룹으로부터 대표 방선균 50균주를 선발하여 16S rRNA 유전자 염기서열을 해석하고 계통학적 위치를 검토한 결과, 94%가 Streptomyces 속에 속하였으며, cluster I (2균주), II (35균주), III (6균주), 그리고 IV (7균주)에 속하는 특징을 나타내었다. 대나무 산림토양으로부터 수집된 Streptomyces 속 방선균 50균주를 Shannon-Wiener법에 의해 다양성 지수를 산출한 결과, 대나무림 낙엽층으로부터 수집된 방선균의 다양도는 3.33으로 부식층과 근권토양 보다 높게 나타났으며, 근권토양으로부터 수집된 방선균의 88%가 cluster II에 속하는 특징을 나타내었다. 본 연구에서 수집한 방선균을 Botrytis cinerea, Xanthomonas campestris 그리고 Xanthomonas axonopodis pv. vesicatoria에 대해 항균활성능을 검토한 결과, 각 74균주, 16균주, 25균주 그리고 24균주가 항균활성능을 나타내었다.

• 한국방사선학회논문지
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• 제17권5호
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• pp.663-670
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• 2023

본 연구에서는 기존의 노이즈 제거 알고리즘을 적용한 영역 확장 기반의 분할 방법과 U-Net을 이용한 분할 방법의 성능을 정량적 평가인자를 이용하여 비교평가 하고자 하였다. 먼저, 전산화단층검사 영상에 median filter, median modified Wiener filter, fast non-local means algorithm을 모델링하여 적용한 뒤 영역 확장 기반의 분할을 수행하였다. 그리고 U-Net 기반의 분할 모델로 훈련을 진행하여 분할을 수행하였다. 그 후, 노이즈 제거 알고리즘을 사용한 경우와 U-Net을 사용한 경우의 분할 성능을 비교 평가하기 위해 평균 제곱근 편차 (root mean square error, RMSE), 최대 신호 대 잡음비 (peak signal to noise ratio, PSNR), universal quality image index (UQI), 그리고 dice similarity coefficient (DSC)를 측정하였다. 실험 결과, U-Net을 이용하여 분할을 수행했을 때 분할 성능이 가장 향상되었다. RMSE, PSNR, UQI, 그리고 DSC 값은 각각 약 0.063, 72.11, 0.864, 그리고 0.982로 noisy한 영상에 비해 각각 1.97배, 1.09배, 5.30배, 그리고 1.99배 개선된 것을 확인할 수 있었다. 결론적으로, 전산화단층검사영상에서 U-Net이 노이즈 제거 알고리즘에 비해 분할 성능 향상에 효과적임을 입증하였다.

• Journal of Ecology and Environment
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• 제40권2호
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• pp.84-88
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• 2016

To understand the effects of habitat characteristics on the genetic diversity of Persicaria thunbergii, three sites of different environmental conditions in a water system were surveyed. Site A was the closest to the source of the water system, and there was a dam between sites A and B. Site C is located on the lowest downstream in the water system. Vegetation survey of four quadrats at each site was performed, and soil samples were collected for physicochemical analysis. Random amplification of polymorphic DNA (RAPD) analysis of ten P. thunbergii individuals at each site was conducted to calculate population genetic diversity and genetic distance among populations. Soil was sterile sand at site A, whereas loamy soil at sites B and C. A pure stand of P. thunbergii appeared at site A, while other species occurred together (such as Humulus japonicus and Phragmites australis) at sites B (Shannon-Wiener index; $H_B=0.309$) and C ($H_C=0.299$). Similar to the species diversity, genetic diversity (Nei's gene diversity; h) within population of site A ($h_A=0.2381$) was relatively lower than sites B ($h_B=0.2761$) and C ($h_C=0.2618$). However, site C was separated from sites A and B in genetic distance rather than the geographical distance (Nei's genetic distance; A~B, 0.0338; B~C, 0.0685; A~C, 0.0833).