• The Korean Journal of Ecology
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• v.23 no.3
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• pp.281-291
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• 2000

The objectives of this study were to classify quantitatively vegetational types of P. densiflora for. erecta forest. The results were summarized as follows. 1) According to the canonical correspondence analysis(CCA), variables such as topography, altitude, available P/sub 2/O/sub 5/, and Mg/sup 2＋/were highly correlated on three axes. Based on the correlations between vegetation units and environmental factors, Rhododendron micranthum community tended to be more distributed in the such situations of high altitude, upper topography, high C/N ratio, low level of Mg/sup 2＋/and Ca/sup 2＋/. Vaccinium koreanum community tended to be more distributed in the such conditions of high altitude, upper topography, high level of Ca/sup 2＋/and Ma/sup 2＋/. 2) According to the results of importance value analysis, Tree layer and Subtree layer in study areas showed high Ⅳ along with P. densiflora for. erecta, Quercus mongonlica, Q. variabilis, Q. serrata, Fraxinus rhychophylla and shrub layer indicated that Ⅳ of P. densiflora for, erecta in Sokwang-ri area was higher than those of the other areas. Therefore, it was considered that P. densiflora for. erecta forest of Sokwang-ri area could be naturally regenerated. 3) According to results of species diversity, the species diversity of Uljin region showed the least low value as 0.6622, other regions appeared about 0.7. In the diversity by vegetation types, Acer pseudosieboldianum community showed high value. 4) According to the analysis of community similarity, Sokwang-Ri region was lowly correlated with Uljin region, while the index among the other areas appeared above 0.6. 5) According to the analysis of interspecific association, it was divided into 2 groups. The species of first group were mainly involved in character species, and the species of second group were involved in differential species groups.

• Korean Journal of Environment and Ecology
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• v.33 no.6
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• pp.722-733
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• 2019

This study was carried out to provide basic information for the ecological preservation management of temple forest (Donghaksa, Gapsa, Sinwonsa) by investigating the ecological characteristics of vegetation structure of the Cultural Heritage Site in Mt. Gyeryongsan National Park based on the Braun-Blanquet vegetation survey method from September 2018 to May 2019. As a result of hierarchical cluster analysis, the forest vegetation was classified into 3 vegetation units (Zelkova serrata - Akebia quinata - Kerria japonica community, VU1; Quercus serrata - Callicarpa japonica - Carpinus cordata community, VU2; and Pinus densiflora - Prunus sargentii - Fraxinus sieboldiana community, VU3). The indicator species of each vegetation unit were 12 taxa, 8 taxa, and 6 taxa, respectively. The result of the importance value analysis showed that Z. serrata had the highest importance value in all vegetation units, and the result of the species diversity analysis showed that the species diversity of VU3 was 0.939, which was relatively higher than other vegetation units. The result of the CCA of correlation between vegetation units and abiotic environmental factors showed that VU2 had a negative correlation with altitude, and biotic environmental factors had no significant correlation with vegetation units.

• Journal of Intelligence and Information Systems
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• v.7 no.2
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• pp.35-49
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• 2001

Over the years, cluster analysis has become a popular tool for marketing and segmentation researchers. There are various methods for cluster analysis. Among them, K-means partitioning cluster analysis is the most popular segmentation method. However, because the cluster analysis is very sensitive to the initial configurations of the data set at hand, it becomes an important issue to select an appropriate starting configuration that is comparable with the clustering of the whole data so as to improve the reliability of the clustering results. Many programs for K-mean cluster analysis employ various methods to choose the initial seeds and compute the centroids of clusters. In this paper, we suggest a methodology to evaluate various clustering programs. Furthermore, to explore the usability of the methodology, we evaluate four clustering programs by using the methodology.

• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.548-557
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• 2001

This study was carried out to classify forest vegetation of Mt. Myeonsan with phytosociological analysis of ZM School and to explain community types with CCA ordination. The research sites were located in the northern part of Kyungsangpook-Do area and in the southern part of Kangwon-Do. The 73 plots were investigated in the study areas which were including 291 plant species. The forest vegetation was classified into Quercus mongolica community group, Juglans mandshurica community group, and Larix leptolepis plantation. Q. mongolica community group was divided into 9 communities such as Rhododendron schlippenbachii community, Symplocos paniculata community, Pinus densiflora community, Betula schmidtii community, Fraxinus rhynchophylla community, Populus davidiana community, Tilia amurensis community, Betula costata community and Betula davurica community. J. mandshurica community group was divided into 5 communities and 4 groups such as Acer mono community (subdivided into Quercus serrata group and typical group), Fraxinus mandshurica community, Ulmus laciniata community (subdivided into typical group and Ribes mandshuricum group), Malus baccata community and Carpinus laxiflora community. And it was entirely classified into 17 vegetation units. According to CCA, Q. mongolica community group showed high positive correlation to topography, altitude and slope degree, and J. mandshurica community group showed high positive correlation to bare rock. However, L. leptolepis community group was not significantly ordinated with the gradient of environmental factors. And in correlation of axes, important environmental variables were topography and altitude.

• Korean Journal of Environment and Ecology
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• v.7 no.1
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• pp.35-48
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• 1993

To compare ecological succession stage between 1987 and 1992, this study was executed in Mt. Puk'an. 26 sample plots of 500$m^2$ were set up. The results were summarized as follows; 1. To analysis plant community structure, the classification by TWINSPAN and CCA, DCA and RA ordination were applied to the study area. That of Mt. Puk'an was divided 4 groups by altitude. The dividing groups are Robinia pseudo-acacia-Quercus spp. community, mixed forest community, Q. serrata community, and Q. mongolica community. The successional trends of tree species over 500m seem to be from Pinus densiflora to Q. mongolica and below 500m in altitude seem to be from Robinia pseudo-acacia through Quercus acutissima, Q. mongolica, Prunus sargentii, Sorbus alnifolia to Q. serrata in the canopy layer. In the case of understory and shrub layer, the successional trends to be from Corylus sieboldiana, Zanthoxylum schinifolium through Rhus trichocarpa, Rhododendron mucronulatum, Rh. schlippenbachii to Acer pseudo-sieboldianum. 2. In comparing successional trends with 1987', the advanced data was not obtained in 1992. It was postulated that succession is not progressed by human disturbance and air pollution.

• 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 Wood Science and Technology
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• v.37 no.3
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• pp.245-254
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• 2009

As a substitute for CCA, which is inhibited due to its environmental pollution and human harmfulness, and CuAz and ACQ with a high cost, okara-based wood preservatives were formulated with okara hydrolyzates using copper sulfate and/or borax as a metal salt. The efficacy of the preservatives and X-ray microanalysis of wood specimens treated with the preservatives were examined to confirm the potential of the okara-based wood preservatives. Most of the preservatives showed excellent decay resistance against brown-rot fungi, Postia placenta and Gloeophyllum trabeum. The efficacy was improved when the acid concentration and temperature used for the hydrolysis of okara increased. In addition, when borax was added into copper sulfate/okara hydrolyzates preservative formulations, any decay was not found in the specimens. From the microscopic observation of the specimens treated with okara-based wood preservatives, it seems that okara is contributed to the fixing of metal salts in wood blocks. Therefore, it is speculated that okara-based wood preservatives can effectively protect wood against fungal attack as CuAz, and that the preservatives are sufficient to use as an alternative wood preservative of CCA, ACQ and CuAz.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.6
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• pp.2761-2765
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• 2016

Opisthorchiasis is a health problem in rural communities of Thailand, particularly in the northeast and north regions. Therefore, this study aimed to investigate raw fish consuming behavior related to liver fluke infection among the population at risk for opisthorchiasis and cholangiocarcinoma (CCA). A cross-sectional descriptive study was conducted in Meuang Yang district, Nakhon Ratchasima province, northeast Thailand, between June and October 2015. Participants were screened for CCA, and samples who had a high score of CCA risk were purposively selected. A predesigned questionnaire was utilized to collect the data from all participants. $X^2-test$ was used for analysis of associations between demographic data and raw fish consumption. The results revealed that participants had past histories of stool examination (33.0%), liver fluke infection (21.0%), praziquantel use (24.0%), raw fish consumption (78.0%), relatives family consuming raw fish (73.0%), and relatives family with CCA (3.0%). Participants consumed several dished related to liver fluke infection, mainly raw fermented fish (13.0%), under smoked catfish (5.00%), raw pickled fish (4.00%), and raw spicy minced fish salad (3.00%). The most common types of cyprinoid fish were Barbodes gonionotus (39%), Hampala dispar (38%), Puntius brevis (37%), Cyclocheilichthys armatus (33%), Puntioplites proctozysron (32%), and Luciosoma bleekeri (30%), respectively. Participants had a low level of knowledge (mean=3.79, SD=0.74), moderate attitude (mean=7.31, SD=7.31) and practice (mean=38.64, SD=6.95) regarding liver fluke prevention and control. Demographic variables like age (>36 years old; $X^2-test=17.794$, p-value=0.001), education (primary school; $X^2-test=18.952$, p-value=0.001), marital status (married; $X^2-test=12.399$, p-value=0.002), and income (<5,000 baht; $X^2-test=27.757$, p-value=0.015) were significantly associated with raw fish consumption. This result indicates that the population had risk consumption for liver fluke infection particularly of various cyprinoid fishes that are $2^{nd}$ intermediate hosts. Therefore, health education is required to improve their behavior.

• 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 Korean Society for Geospatial Information Science
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• v.4 no.2 s.8
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• pp.181-193
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• 1996

A new technique for land cover classification which applies digital image pre-classified by unsupervised classification technique, clustering, to Canonical Correlation Analysis(CCA) was proposed in this paper. Compared with maximum likelihood classification, the proposed technique had a good flexibility in selecting training areas. This implies that any selected position of training areas has few effects on classification results. Land cover of each cluster designated by CCA after clustering is able to be used as prior information for maximum likelihood classification. In case that the same training areas are used, accuracy of classification using Canonical Correlation Analysis after cluster analysis is better than that of maximum likelihood classification. Therefore, a new technique proposed in this study will be able to be put to practical use. Moreover this will play an important role in the construction of GIS database