• 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.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.6
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• pp.1768-1774
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• 2008

The particulate behaviors of nickel ferrite were investigated under the simulated PWR shutdown chemistry conditions. Temperature of the simulated water with concentration of 0.1 ppm Li and 2,000 ppm B was dropped from $300^{\circ}C$ to $150^{\circ}C$ with a rate of $0.625^{\circ}C/min$ and then constantly maintained at $150^{\circ}C$ under the pressure of 2,500 psi. The on-line particle counting and the concentration measurement of nickel dissolved were performed under 5, 15 and 25 cc/kg $H_2O$ dissolved hydrogen. Experimental results showed that total particle count in the simulated water was not greatly changed for three hydrogen concentrations as temperature was decreased. However, particles were smaller as temperature was decreased and then maintained constantly. The degree of variation in particle size distribution was greater at 15 cc/kg $H_2O$ dissolved hydrogen than any other dissolved hydrogen concentrations. Concentration of nickel ion was increased as temperature was decreased and was higher at 15 cc/kg $H_2O$ dissolved hydrogen than any other dissolved hydrogen concentrations. Theses results show that nickel ferrite is unstable with temperature variation and at dissolved hydrogen concentration of 15 cc/kg $H_2O$.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.11
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• pp.2689-2696
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• 2015

Radioactive isotopes which are manufactured using a cyclotron in a radioisotope used for radiation diagnosis is affected by the production yield according to size and shape of the beam and beam uniform degree from irradiated location when the proton beam investigated the target by cyclotron. Therefore, in this paper developed the BPM(Beam Profile Monitor) device capable of measuring the beam cross-section at the cyclotron beam line. It was configured so as to be able to remote control the BPM device in LabView and used the BPM program it was to be able to easily monitor and display to analyze the graph of two-dimensional graph and a three-dimensional beam distribution numerical information of the beam obtained while scanning the tungsten wire to the X and Y axis. The time it takes to measure the beam can be confirmed 37seconds when step motor driving speed was 2000pps. Through a beam readjusted based on the measured beam distribution information by optimizing the beam distribution it can be made to maximize the RI production yield and contribute supply stabilization.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.590-600
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• 2021

This study compared the stand structure of Abies koreana forests between Mt. Jirisan and Mt. Hallasan by analyzing DBH distribution, stem vitality, crown structure, importance value, species diversity, and DCA. The data were acquired through the national long-term ecological research project conducted by the Ministry of Environment. In the comparison of DBH class distribution, the stem density of A. koreana with DBH < 20 cm was higher in Mt. Hallasan than that in Mt. Jirisan; however, the stem density of A. koreana with DBH > 20 cm was higher in Mt. Jirisan than that in Mt. Hallasan. For A. koreana stem vitality, the ratio of alive standing was higher in Mt. Jirisan (72.0%) than in Mt. Hallasan (60.7%), whereas the ratio of alive leaning was higher in Mt. Hallasan (10.2%) than in Mt. Jirisan (1.1%). A. koreana stand in Mt. Jirisan was a mature stand with four evenly developed and distinct layers, whereas the tree layer in Mt. Hallasan was less than 10 m and the stand had three layers without a subtree layer. Mt. Hallasan's importance value of A. koreana was 39.4% higher than Mt. Jirisan's importance value of 26.6%. The species diversity of the A. koreana community of Mt. Jirisan was 2.52 times higher than that of Mt. Hallasan, which was 1.58. DCA results revealed that the average distance between Mt. Jirisan and Mt. Hallasan was relatively distinguished, and the degree of scattering of species composition of Mt. Jirisan was relatively dense compared with that of Mt. Hallasan.

• Journal of Climate Change Research
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• v.3 no.1
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• pp.51-69
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• 2012

This work aims to propose a vulnerability assessment methodology of ecosystem at present time, and an to suggest an adaptation strategy of ecosystem in the future for local government, in the fields of plant, animal and conservation area, which would occurred due to climate change. Vulnerability assessment in ecosystem includes first, tree growth and distribution part, mainly for conifers, secondly, insect part for pest and bee, and thirdly conservation area management part, especially at the national parks. To evaluate the degree of vulnerability of each substitute variables, such as exposure of climatic element, sensitivity, and adaptation ability, are respectively selected. Vulnerabilities of conifer growth and distribution, pest and bee, and national park management seem to be strongly influenced by the exposure of climatic element than other factors, such as sensitivity and adaptation ability. With time regional gaps of ecosystem vulnerability are expected to be greater in both conifers growth and distribution, and national park management, but reduced in pest and bee in 2100 in comparison with present time.

• Korean Journal of Remote Sensing
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• v.36 no.6_1
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• pp.1339-1348
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• 2020

Phytoplankton controls marine ecosystems in terms of nutrients, photosynthetic rate, carbon cycle, etc. and the degree of its influence on the marine environment depends on their physical size. Many studies have been attempted to identify marine phytoplankton size classes using the remote sensing techniques. One of successful approach was the three-component model which estimates the chlorophyll concentrations of three phytoplankton size classes (micro-phytoplankton; >20 ㎛, nano-; 2-20 ㎛ and pico-; <2 ㎛) as a function of total chlorophyll. Here, we examined the applicability of Geostationary Ocean Colour Imager (GOCI) to the mapping of the phytoplankton size class distribution in the East Sea. A fit of the three-component model to a biomarker pigment dataset collected in the study area for some years including a large harmful algal bloom period has been carried out to derive size-fractioned chlorophyll concentration (CHL). The tuned three-component model was applied to the hourly GOCI images to identify the fractions of each phytoplankton size class for the entire CHL. Then, we investigated the distribution of phytoplankton community in terms of the size structure in the East Sea during the harmful Cochlodinium polykrikoides blooms in the summer of 2013.

• Journal of the Korean Association of Geographic Information Studies
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• v.24 no.4
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• pp.26-40
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• 2021

This study aims to propose improvement plans and directions of existing policies to build a Barrier-Free city for the socially underprivileged. We conducted correlation analysis and T-test based on the results of a survey of the general public including the socially underprivileged to understand how their satisfaction with the use of facilities close to their daily lives, such as housing, sales·business facilities, affects their happiness. The results are as follows: First of all, the socially underprivileged experienced discomfort and barriers in urban life more than the privileged, and there was a negative(-) correlation between the degree of discomfort and barrier that the socially underprivileged experienced and happiness in urban life. Second, as a result of analyzing the difference in satisfaction with the life·welfare·leisure environment indicators, the satisfaction with the life environment showed a significant difference between the socially underprivileged and the privileged, and it was found that satisfaction in the life environment had the greatest effect on happiness to the socially underprivileged. We examined the current status and the spatial distribution of BF-certified facilities, one of the representative policies for the socially underprivileged to support their urban life without any obstacles, based on the above outcome, and most certified facilities were concentrated in welfare environment. In addition, we used ArcGIS to analyze that BF-certified facilities have been being supplied to people who really need them and saw that the spatial distribution of the socially underprivileged (elderly, children, and infant) and the distribution of BF certification facilities were somewhat consistent, but were intensively supplied to urban areas.

• Journal of Soil and Groundwater Environment
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• v.27 no.spc
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• pp.51-63
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• 2022

In this study, the TPH(Total Petroleum Hydrocarbon) contamination and microbial ecological characteristics in petroleum-contaminated site were investigated through the correlation among the vertical TPH contamination distribution of the site, the geochemical characteristics, and the indigenous microbial ecology. The high TPH concentration showed in the vicinity of 3~4 m or less which is thought to be affected by vertical movement due to the impervious clay layer. In addition, the TPH concentration was found to have a positive correlation with Fe²⁺, TOC concentration, and the number of petroleum-degrading bacteria, and a negative correlation with the microbial community diversity. The microbial community according to the vertical distribution of TPH showed that Proteobacteria and Firmicutes at the phylum level were dominant in this study area as a whole, and they competed with each other. In particular, it was confirmed that the difference in the microbial community was different due to the difference in the degree of vertical TPH contamination. In addition, the genera Acidovorax, Leptolinea, Rugoshibacter, and Smithella appeared dominant in the samples in which TPH was detected, which is considered to be the microorganisms involved in the degradation of TPH in this study area. It is expected that this study can be used as an important data to understand the contamination characteristics and biogeochemical and microbial characteristics of these TPH-contaminated sites.

• Phonetics and Speech Sciences
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• v.14 no.3
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• pp.41-49
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• 2022

The average acoustic distribution of American English speakers was statistically compared with the English-speaking patterns of gifted students in a Science Academy in Korea. By analyzing speech recordings, the duration time of which is much longer than in previous studies, this research identified the degree of acoustic proximity between the two parties and the predictability of English academic achievement of gifted high school students. Long-term spectral acoustic power distribution vectors were obtained for 2,048 center frequencies in the range of 20 Hz to 20,000 Hz by applying an long-term average speech spectrum (LTASS) MATLAB code. Three more variables were statistically compared to discover additional indices that can predict future English academic achievement: the receptive vocabulary size test, the cumulative vocabulary scores of English formative assessment, and the English Speaking Proficiency Test scores. Linear regression and correlational analyses between the four variables showed that the receptive vocabulary size test and the low-frequency vocabulary formative assessments which require both lexical and domain-specific science background knowledge are relatively more significant variables than a basic suprasegmental level English fluency in the predictability of gifted students' academic achievement.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.100-100
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• 2020

Wheat is mainly composed of carbohydrate but it contains a moderate amount of protein, which gives a very useful characteristics to flour food such as the unique elasticity and stickiness of the dough. We developed a calibration equation for analyzing crude protein content using Near Infrared Spectroscopy to quick analyze the crude protein content of wheat germplasm stored in the National Agrobiodiversity Center, RDA, Korea. The 1,798 wheat germplasms were used to draw up the calibration formula. The crude protein's interval distribution of 1,798 wheat germplasms used for the calibration was 7.04-20.84%, the average content was 13.2%, and standard deviation was 2.6%. The germplasms distribution was composed of a suitable group for the preparation of the calibration formula because the content distribution was a normal, excluding the 13.0-15.5% content section. In order to verify the applicability of the NIRS prediction model, we measured the crude protein content of the 300 wheat germplasms that were not used for the calibration using both Kjeldahl analysis and NIR spectrum. The analysis value calculated using each method were statistically processed, and the test results and statistical indicators of the predictive model were compared. As a result, The R² value of the optimized NIRS prediction model was 0.997, and the Standard error of Calibration value(SEC) was 0.132, and slope value was 1.000. With prediction model selection, compared to Kjeldahl method, R² values were 0.994(Kjeldahl), 0.998(NIRS), and the SEC value were 0.191 and 0.132, respectively, comparing the statistical indices of the forecast model. And slope value were 1.013, 1.000, respectively. The analysis of crude protein content by the NIRS predictive model developed by each statistical index showing similar figures is judged to show a high degree of correlation with the Kjeldahl analysis. The proven calibration equation will be used to measure the crude protein content of wheat germplasms held by the National Agrobiodiversity Center, and by dividing the wheat germplasms by their use according to the crude protein content, it will provide useful information to relevant researchers.