• Journal of Korean Society of Forest Science
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• v.113 no.1
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• pp.51-65
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• 2024

Phyto-sociological methods were used in this study to assess the vegetation structure of a forest stand at Mt. Goehwa in Sejong-Si with the aim of providing vegetation information for urban forest utilization and management plans. The actual forest vegetation was classified into two types of community groups (Quercus serrata-Lindera obtusiloba and Coreopsis lanceolata community groups) at the highest hierarchical level. The Q. serrata-L. obtusiloba community group was classified into six units, which included artificial forest and natural forest vegetation. Artificial forests were classified into three communities (Pinus rigida, Castanea crenata, and Robinia pseudoacacia), whereas natural forests were classified into three communities (Quercus variabilis, Quercus acutissimaa, and Pinus densiflora). The Coreopsis lanceolata community group, which exhibited vegetative characteristics of urban forest edge areas, was categorized into four units. The urban forest edges were classified into four communities (Indigofera bungeana, Lespedeza bicolor, Amorpha fruticosa, and Lespedeza cuneata). Accordingly, the vegetation structure of Mt. Goehwa was categorized into 10 vegetation unit systems. An importance value analysis showed the highest importance value for C. crenata at 6.7%, followed by P. rigida at 6.4%, and R. pseudoacacia at 6.3%, indicating that the ecological impact of plantation species can be significant on Mt. Goehwa. A community coefficient of similarity analysis revealed that the artificial and natural forests had similar species compositions; however, both forests differed from the urban forest edge. This variation was further confirmed by Detrended correspondence analysis(DCA), with similar results. Canonical correspondence analysis(CCA) showed that the artificial forest and natural forest community types were positively correlated with altitude, bare rock, and the present species. By contrast, the urban forest edge community types were negatively correlated with these factors.

• The Korean Journal of Ecology
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• v.25 no.3 s.107
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• pp.153-161
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• 2002

This study was carried out to classify forest vegetation of the Mt. Naeyeon with phytosociological analysis of ZM school and to explain ordination of communities with CCA. The research sites were located between the northern part of Pohang-si area and the southern part of Yeongdeok-gun area. The 70 plots consisted of 253 species were investigated. The forest vegetation was classified into Quercus mongolica community, Q. variabilis community, Pinus densiflora community, Carpinus laxiflora community and Zelkova serrata community. Q. mongolica community was divided into 2 groups such as Rhododendron schlippenbachii group and Euonymus oxyphyllus group and Q. variabilis community was divided into 3 groups such as Syneilesis palmata group, Lespedeza$\times$tomentilia group and Tilia mandshurica group, and Z. serrata community was divided into 2 groups such as Carpinus cordata group and Diospyros lotus group. According to the results of CCA ordination, Q. mongolica community showed high positive correlation to altitude and topography, whereas it showed negative correlation to bare rock. But Z. serrata community showed the opposite tendency to Q. mongolica community, Altitude was considered as the most important factor among 5 environmental variables in the correlation with axes.

• Journal of the Korean Society for Nondestructive Testing
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• v.32 no.5
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• pp.494-501
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• 2012

In the present paper, the ultrasound blood images were measured at both the human radial artery(RA) and common carotid artery(CCA), depending on the age, and the pulsatility index of blood echogenicity(PIBE) was analyzed. In addition, the ultrasound blood images were measured at both RA and CCA of both the stroke patients and the control group, and PIBE was compared. PIBE of RA for the young group was similar with that for the old group ($0.13{\pm}0.11$ and $0.16{\pm}0.03$). PIBE of CCA for the young group, however, was larger than that for the old group ($0.70{\pm}0.21$ and $0.32{\pm}0.01$), and was more variable depending on the subject. Similarly, the fibrinogen concentrations of the patients ($336{\pm}61$ and $340{\pm}126mg/dl$) were more than that of the control group ($264{\pm}38$ and $257{\pm}43mg/dl$), for both RA and CCA. The results indicate the possibility of the ultrasonic test on the correlation between erythrocyte aggregation and stroke, and it is expected that the in-vivo EA measurement would be clinically useful.

• Korean Journal of Environment and Ecology
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• v.31 no.3
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• pp.297-317
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• 2017

The research has been conducted in order to classify the vegetation types of natural forest in Mt. Janggunbong, Bonghwa-Gun and establish its following characteristics of stands. Vegetation data were collected by June in 2014 to August in 2016. Based on the 71 quadrates, we carried out an analysis of species-area curve, vegetation types, importance value, species diversity, coincidence method and CCA. As a result of the species-area curve, it was showed the proper investigation, vascular plants consisted a total of 227 taxa; 67 families, 152 genera, 197 species, 3 subspecies, 27 varieties. The forest vegetation was classified into 7 vegetation units, when it comes to a community group, they are classified into the Quercus mongolica community group. As for community, Q. mongolica community group is classified into the Acer pictum subsp. mono community, Pinus koraiensis community and Q. variabilis community. As for group, A. pictum subsp. mono community is classified into Lychnis cognata group and Deutzia glabrata group. The P. koraiensis community is classified into A. komarovii group and P. koraiensis typical group. The Q. variabilis community is classified into Parthenocissus tricuspidata group and Q. variabilis typical group. As for subgroup, P. tricuspidata group is classified into P. tricuspidata typical subgroup and Salix caprea subgroup. As a result of the importance value, Q. mongolica showed highest importance value in tree layer of vegetation units 1, 2, 3, 4 and 5. Betula schmidtii showed highest importance value in tree layer of vegetation unit 6. P. densiflora showed highest importance value in tree layer of vegetation unit 7. In subtree layer, shrub layer and herb layer of vegetation units 6 and 7, Q. mongolica and Q. variabilis showed high importance value. This implying that a vegetation units 6 and 7 is predicted to be composed by Q. mongolica and Q. variabilis. As for species diversity, vegetation units 1, 2 and 3 showed high species diversity(2.130~2.353). It was considered to be due to the topographical characteristics of valley. As a result of coincidence method and CCA, altitude showed high correlation than other environmental factor.

• Korean Journal of Environment and Ecology
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• v.32 no.1
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• pp.77-96
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• 2018

We investigated and analyzed three Korean island sites (Bijin-do, Ae-do, and Bogil-do) and one Japanese site (Tachibanayama) of sword-leaf litsea (Actinodaphne lancifolia) forests, known as the climax forest, to discuss the vegetation succession sere of warm-temperature evergreen broad-leaved forests. We then reviewed the literature in Korea, Japan, China, and Taiwan to consider the distribution characteristics of evergreen broad-leaved forests, vegetation succession sere, and climax tree species. Although Mt. Tachibana and Ae-do showed the most advanced vegetation structure, the soil and ordination (CCA) analysis indicated that it was not enough to consider that the sword-leaf litsea forest was at the climax stage in the warm-temperature region. The Actinodaphne lancifolia forest is sparsely distributed in Korea and Japan while the common types of vegetation in the warm temperate zone region in East Asia are Machilus spp., Castanopsis spp., and Cyclobalanopsis spp. The vegetation succession sere of the Korean warm-temperature region is thought to have a secondary succession such as Pinus thunbergii, P. densiflora, Q. serrata (early stage) through Machilus thunbergii, innamomum yabunikkei, Neolitsea sericea, Actinodaphne lancifolia (middle stage) to Castanopsis sieboldii, Q. acuta, Q. salicina (climax stage). However, Machilus thunbergii will be the climax species as an edaphic climax in places where there is a strong influence of the sea wind, or it is difficult to supply the seeds of Castanopsis spp. and Cyclobalanopsis spp.

• The Journal of the Korea Contents Association
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• v.9 no.9
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• pp.97-104
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• 2009

This paper describes comparison and analysis of methodology which enables us in order to search the projection technique of optimum for projection in the plane. For this methodology, we applies the high-dimensional facial motion capture data respectively in linear and nonlinear projection techniques. The one core element of the methodology is to applies the high-dimensional facial expression data of frame unit in PCA where is a linear projection technique and Isomap, MDS, CCA, Sammon's Mapping and LLE where are a nonlinear projection techniques. And another is to find out the methodology which distributes in this low-dimensional space, and analyze the result last. For this goal, we calculate the distance between the high-dimensional facial expression frame data of existing. And we distribute it in two-dimensional plane space to maintain the distance relationship between the high-dimensional facial expression frame data of existing like that from the condition which applies linear and nonlinear projection techniques. When comparing the facial expression data which distribute in two-dimensional space and the data of existing, we find out the projection technique to maintain the relationship of distance between the frame data like that in condition of optimum. Finally, this paper compare linear and nonlinear projection techniques to projection high-dimensional facial expression data in low-dimensional space and analyze it. And we find out the projection technique of optimum from it.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1071-1079
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• 2011

In this study, coal combustion ash (CCA) was evaluated for its stabilization effect on acidic mine waste with column experiment. Total of six treatments were installed depending on mixing ratio between coal wastes and CCA (0, 20, 40%) and mixing method (completely mixing and layered). Artificial acidic rain (pH 5.6) was used for feeding solution with flow rate of $0.05mL\;min^{-1}$. Result showed that higher pH of leachate was observed as more CCA was mixed. The highest pH in leachate was measured when 40% of CCA was mixed with coal waste (pH of 5.8). Also, complete mixing with CCA and coal waste was more effective to increase the pH of leachate than layered treatment. Regarding the reduction of soluble Fe amount, the highest efficiency (78%) was observed when 20% of coal ash was completely mixed with mine waste. Based on those result, optimum mixing ratio of coal ash with mine waste can be ranged 20-40% depending on environmental circumstances in the field.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.4
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• pp.643-650
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• 2020

The phased array antenna has an advantage enabling rapid beam aim without the mechanical rotation of the antenna, because it arranges multiple elements in a linear or planer (grid or circular) and electronically controls the phase for each element. The planar array antenna is generally used a grid array and a circular array, and the circular form has the higher resolution comparing to the grid form due to the its structural characteristics. However, a concentric circular array (CCA) or a concentric ring array (CRA) with multiple circular arrays which each has different radius is used in the limited area, because the entire radius should be increased for the circular array with a number of elements. In this paper, we introduce the angle-of-arrival (AOA) estimator for an adaptive beamforming satellite system based on CRA and provide the simulation results for performance evaluation. In addition, simulation results are compared and analyzed to the case for the circular array antenna.

• Korean Journal of Environmental Biology
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• v.28 no.3
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• pp.115-124
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• 2010

In order to find out the short-term phytoplankton dynamics during summer season in Jinhae Bay, we investigated the environmental factors and phytoplankton population densities at 16 stations. A total of 66 phytoplankton species were appeared, diatoms occupied more than 80% of total species, and the others were dinoflagellates and raphidophyceaes. The dominant species were diatoms Chaetoceros affinis, C. didymus, C. pseudocurvisetus, Leptocylindrus danicus, Pseudonitzchia pungens, Skeletonema costatum and dinoflagellates Cochlodinium polykrikoides, Gymnodinium impudicum, Karenia mikimotoi, Prorocentrium minimum, Protoperidinium bipes and Scrippsiella trochoidea. According to multidimensional scaling (MSD) and cluster analysis based on phytoplankton community data from each station, the Jinhae bay was divided into two groups. The first group included stations in the inner part of Masan Bay, which is strongly influenced by high nitrogen loading and low salinity by river discharge. The second group included the other remained stations. Based on canonical correspondence analysis (CCA), small-size dinoflagellates K. mikimotoi, P. minimum, P. bipes and S. trochoidea and centric diatom C. pseudocurvisetus and S. costatum, which is dominanted in the inner area of bay, were related with DIN (ammonium, nitrate, nitrite). These results imply that the study area was grouped into the two water masses (inner and outer water of Masan Bay) and inner waters had higher phytoplankton abundances and Chl.a concentration than outer waters. As a result, summer phytoplankton peaks in the inner shallow bay were stimulated by increases in nitrogen and temperature.

• Journal of Ecology and Environment
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• v.29 no.6
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• pp.521-529
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• 2006

This study was carried out to classify all forest vegetation types in Ulleung Island, Korea using the methodology of the Z.-M. school's phytosociology, and map out the spatial distribution patterns of those vegetation types. The forest vegetation was classified into the mountain forest type (Acer okamotoanum community group) and maritime forest type (Artemisia scoparia community group). Vegetation units at the community level were divided into three categories; six communities, sixteen groups, and seven subgroups, giving a total of 22 communities. Total area for mapping was 5,544.9 ha, of which Fagus engleriana community accounted for 1,952 ha (35.2%), Hedera rhambea community ror 1,196 ha (21.6%), Camellia japonica community for 1,104 ha (19.9%), Sambucus sieboldiana var. pendula community for 612 ha (11.0%), Aster spathulifolius community for 506 ha (9.1%), and Tsuga sieboldii - Pinus parviflora community for 174 ha (3.1%). According to canonical correspondence analysis (CCA), variables such as $Mg^{2+}$, pH, $Ca^{2+}$ were positively correlated in maritime vegetation types, and variables such as total nitrogen, carbon content, C/N ratio and ration exchange capacity (CEC) were highly correlated in mountain vegetation types, respectively. The sea level and the slope direction were not showing regular trend as a factor to decide on species diversity, evenness and richness in this research area. But it seems to be affected by topography, slope degree and dominance vegetation.