• Korean Journal of Environmental Biology
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• v.32 no.2
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• pp.95-101
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• 2014

In order to investigate effects of elevated $CO_2$ concentration and temperature on the ecological niche of Quercus serrata in Korea. We divided experimental condition in the greenhouse that are control (ambient condition) and treatment with elevated $CO_2$ (approximately 1.6 above than control) and increased air temperature (approximately $2.2^{\circ}C$ above than control). We measured twenty kind characters of seedlings and calculated the ecological niche breadth. As a result, the ecological niche breadth, treatment was widened in the light gradient than the control, was narrowed in the moisture and nutrient gradient. This is may be predicted when the global warming progress, Q. serrata is increases resistance to light environment, and decrease resistance to moisture and nutrient environment. According to the principal component analysis (PCA), control and treatment were arranged based on factor 1 and 2 in each environment gradients. Ecological response is involved variety characters. Among them, indicating that Characters of production is involved in many a parts.

• Korean Journal of Plant Resources
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• v.19 no.2
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• pp.300-307
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• 2006

To clarify the morphological and geographical differentiation among the polyploid complexes of L. lancifolium collections in Korea, the mo게hological variation of 173 accessions were analyzed by ANOVA (one-way analysis of variance) and PCA (principal component analysis) on the basis of 38 morphological characters. 173m accessions were grouped into 78 diploids and 95 triploids by ploid levels and the triploids separated into 75 inland triploids (all around the Korea) and 20 island triploids (Backryung-do and Sochung-do, westemmost and northernmost islands of Korea) by geographic distribution and morphology. Island triploids showed significant morphological differences with inland triploids in ANOVA by many floral and leaf characters. In PCAs, diploids were separated from inland triploids by having longer plant height, smaller flower characters, higher pollen fertility and more stomata. The first four principal components accounted for 44.1% of the total variation. Plots of the island and inland groups for the first and second principal components separated each other with slight overlapping. Although the ploid forms are different between diploid and island triploid, island triploids were more closely overlapped with diploids by principal component 1 and 2 than inland triploids. This reflects that the whole external morphology of island triploids are similar to that of diploids. This, the phenotypic differentiation between inland and island triploids seems to be partly related to their geographical origins.

• The Journal of the Korea Contents Association
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• v.12 no.7
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• pp.437-444
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• 2012

This study features an analysis of the socio-economic factors of ten cities on the Honam-line that affect the number of train passengers. The 3 main factors based on the principal component analysis were the population, the distance between two regions, and the area size of each region while the number of automobiles has been conventionally used instead of the area size of each region. A formula to predict the train passengers by the regression analysis was developed and showed a good agreement to the number of real passengers. When Honam highspeed railway is opened, the traveling time between two regions as well as the area size of each regions should be more precisely considered.

• Food Science and Preservation
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• v.23 no.5
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• pp.727-737
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• 2016

This study was carried out to determine the descriptive sensory profile of oriental melon. The sensory profile of oriental melons (cultivated in Seonju, Kyungsangbuk-do) were used quantitative descriptive analyses and twelve trained panel developed the total forty sensory attributes related appearance, aroma, texture etc. Six appearances attributes and two aromas attributes were derived from whole oriental melon with skin. Five aromas, six tastes and six textures were derived from the mesocarp of oriental melon. And also, oriental melons were analyzed for pH, titratable acidity, solid soluble contents and weight. The weight, titratable acidity and soluble solid content of oriental melons showed significant differences according to samples. And also, in the sensory attributes of these samples by trained panel and consumer test, there were significant differences between organic cultivated samples and conventional cultivated samples. Based on principal component analysis of sensory attributes data by trained panel and consumer, oriental melons were primary separated along the first principal component, which accounted for 27.73% (trained panel test) and 19.82% (consumer test) of total variance (trained panel test; 58.36%, consumer test; 46.18%) between the samples farm, cultivation method, total acidity, sweet aroma, bitterness, etc. Generally, whole oriental melon with skin showed significant differences in the sensory attributes according to cultivation method and farms. But, the mesocarp and endocarp part showed not certainly differences in the sensory attributes between organic cultivated samples except conventional cultivated samples.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.242-247
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• 2011

Soil management for environment-friendly agriculture depends on the effects of soil microbial activities and soil fertility. To improve soil health for the upland crops, this study evaluated a relationship between soil chemical properties and soil microbial diversities at 25 sites in upland soils in Gyeongnam Province. The average nutrients in the upland soils were 1.7 times for available phosphorous, 1.4 times for exchangeable potassium and 1.5 times for exchangeable calcium higher compared to recommend concentrations in the upland soils. We found a significant positive correlation between the soil organic matter and the soil microbial biomass C (p<0.01). Contents of organic matter and dehydrogenase in the inclined piedmont soils were significantly higher than those in the other topographical soils (p<0.05). In addition, concentrations of organic matter and microbial biomass C in the loam soils were significantly higher than in the silt loam soils (p<0.05). In principal component analyses of chemical properties and microbial populations in the upland soils, our findings suggested that available phosphorous should be considered as potential factor responsible for the clear upland soils differentiation. The soil organic matter was positive correlation with Bacillus sp. and fungi, whereas soil pH was also positive correlation with Pseudomonas sp. in upland soils.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.220-227
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• 2014

This paper introduces and applies the World Bank's methodology for constructing composite index or aggregating indicators. After recalculating the world competitiveness index of IMD using Unobserved Component Model(UCM) we compare it with the existing index and try to find some implications. We also try to construct the composite index for measuring the performance of local finance. We employ the Principal Component Analysis(PCA) for validating the appropriateness of selected indicators used in making the composite index. We found that the UCM and PCA are very useful and will be used widely in various evaluations such as regional development, local finance, local competitiveness and public enterprise, etc.

• Journal of Korea Technology Innovation Society
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• v.15 no.3
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• pp.481-499
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• 2012

This paper shows a empirical results by adopting Kauffman' NK model. First, we find interdependence parameter K is nine in the technological ecosystem Landscape. According to principal component analysis, our technological ecosystem landscape is based on K=N-1 technology structure. Second, to Kauffman NK model, our technological ecosystem landscape is completely uncorrelated each other and contains a large number of local optima. As additional technology rises, the number of local optima rises rapidly. Our results mean that the more complexity in the technological ecosystem landscape, the less effective technology innovation will be in our country's technology system.

• Education of Primary School Mathematics
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• v.21 no.4
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• pp.431-444
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• 2018

The purpose of this study was to develop and validate a mathematics anxiety scale for elementary students in South Korea. Based on the literature review, I developed two types of survey items measuring elementary students' mathematics anxiety. Teachers or students may use survey measurements selectively according to the students' participants in mathematics private institutions. In order to assess the reliability and validity of survey items, I conducted surveys with elementary students. The sample consisted of 300 elementary students in public elementary schools in Seoul. A total of 28 items were developed and examined for the internal consistence. The results showed that the proposed scale was appropriate to represent the mathematics anxiety of elementary students. The survey items of this study could be applied for assessing elementary students' mathematics anxiety regardless of their gender and age factors.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.9
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• pp.3900-3914
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• 2012

This study examined the background of the recent global financial crisis and the concept of one of the financial derivatives such as the credit default swap(CDS) or synthetic CDO(collateral debt obligations), given the rapid growing and changing the over-the-counter derivative markets in their volume and structures. In comparison with the previous literature such as the study of Park & Kim (2011), this research empirically performed more thorough and comprehensive investigations to find any financial characteristics or attributes to determine the CDS spreads. Regarding the results obtained from the multiple regression models, the explanatory variables such as STYIELD3, SLOPE, INASSETS, and VOLATILITY, showed their statistically significant effects on all the tested dependent variables(DVs). Another procedure such as the principle component analysis(PCA), was also performed to account for additional IDVs as possible determinants of the dependent variables. Subsequent to this analysis, larger coefficients of each corresponding eigenvector such as BETA, PFT2, GROWTH, STD, and BLEVERAGE were found to be possible financial determinants. For robustness, all the IDVs were employed to be tested in the 'full' regression model with stepwise procedure. As a result, STYIELD3, SLOPE, and VOLATILITY, and BETA showed their statistically significant relationship with all the dependent variables of the CDS spreads.

• Journal of the Korea Convergence Society
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• v.10 no.9
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• pp.323-332
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• 2019

The purpose of this study was to examine the validity and reliability of the Revised Multidimensional Coping Scale(MCS-R) in university student who attended smoking cessation group therapy. Data were collected from 198 university students. Construct validity using exploratory factor analysis were conducted and convergent validity using Resilience scale, Patient Health Questionare-9(PHQ-9) were conducted. A Principal components analysis with varimax rotation and Kaiser normalization identified a thirteen-factor accounting for 69.7% of the variance in scores. Also, the internal consistency(0.66-0.94) and test-retest reliability was adequate(0.44-0.85) in all subscales of the MCS-R. The MCS-R has adequate psychometric characteristics so it can be used to verify.