• Economic and Environmental Geology
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• v.33 no.2
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• pp.91-100
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• 2000

It has been more than ten years since Dukun mine was abandoned. Tailings of waste deposits and slime dumps in the abandoned Dukum mine have been left to be deserted for fifty years. The results of fifty years of neglecting are nothing short of major environmental problems. Slime dumps have been exposed to air and water in the mine over ten years and then soil profile has been formed well. Soil in the upper layer (A horizon) is the light gray color due to the leaching of cations. Soil in the lower layer (A2 horizon, 0.2∼0.3m)is tinted with reddish brown and yellowish brown color due to the development of iron oxides and iron hydroxides. Soil in the lower part of B horizon of (1.0∼3.0m) with the growth of copper and zinc oxides exposes to the bluish green, light blue, and dark gray. Ranging from 3m to 8m in depth, 85 samples were taken from 22 sampling sites with 50m intervals located on the slime dump area with hand auger and trench (open cut). As tailings was distributed, heavy metal elements extracted by the process of surface water and ground water move and disperse in to the hydrosphere. Waste dumps were distributed in and around the mine and water draining from those dumps be a potential source of contamination. Soils, thus, can be dispersed into downslope and downstream through wind and water by clastic movement. These materials may be deposited in another horizon if the water is withdrawn, or if the materials are precipitated as a result of differences in pH, or other conditions in deeper horizons. These were primarily associated with acid mine drainage. The characteristics and rate of release of acid mine drainage are influenced by various chemical and biological reactions at the source of acid generations. Prolonged extration of heavy metal elements has a detrimental effect on the agricultural land and residental area. Twenty soil samples were collected from the agricultural land in the area (0∼30 cm). Seventeen samples were also taken from the sediment in the stream running alongside the dumps. The dispersion patterns of heavy metal elements are as follows: The content of As ranged 2∼6 ppm in a horizon, 20∼125 ppm in B horizon with large amount of clay mineral is concentrated and the content of Cd ranged 1∼2 ppm in A horizon, 4∼22 ppm in B horizon. Like Cd, the content of As, Cu, Zn, Pb in B horizon is higher than that in A horizon (approximately 5∼100 times). When soil formation proceeds in stages, it is necessary to investicate the B horizon with the concentration of heavy metal and preventive measures will have to established.

• Journal of Navigation and Port Research
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• v.46 no.3
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• pp.251-258
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• 2022

Donghae Port is adjacently located to a residential area wherein 26,933 generations are creating a living environment. The areas comprise Song-jeong village (5,754 generations) and Bukp-yeong village (21,179 generations). Major cargoes handled in Donghae Port are dusty limestone, cement, anthracite, and bituminous coal, etc. In the process of handling such cargoes, air pollutants including oxide dust and fine dust which adversely impact the living conditions and health of residents are generated, causing air pollution in the vicinity of the port. Currently, Donghae Port is making an effort to improve the operation environment of the infrastructure and equipment in stages, for the purpose of reducing air pollutant emissions caused by the port industries in a long-term perspective. In this study, the sphere of influence of fine dust exposure and the degree of air pollution in the surrounding area were analyzed such as the state of fine dust concentration and diffusion in the vicinity of Donghae Port, fine dust diffusion pattern and spatial distribution of high-concentration considering wind direction and speed characteristics during the day and seasonal cycles. A more effective plan to reduce the concentration of fine dust in nearby areas by combining reduction plan, is being developed in terms of improvement regarding port infrastructure and equipment, and reduction measures considering the characteristics of the atmosphere environment according to the daytime, nighttime and season.

• Journal of the Korean Association of Geographic Information Studies
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• v.8 no.4
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• pp.102-113
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• 2005

Ecosystem is composed of human, biotic and abiotic environment. Landscape is an ecosystem which appear in a unit region. These landscape are the spatiotemporal land mosaic which is combined with various landscape elements. And, land use and land cover changes are important factors of landscape structure changes. This study is mainly focused on the analysing the spatiotemporal change patterns of Daegu metropolitan sphere forest landscape, using landscape indices and Ecosystem Service Value (ESV) which quantify ecosystem structures and functions. The results of this study are as follow: The encroachment and fragmentation of forest were due to linear developments, i. e. road construction, rather than large-scale developments such as residental lands or industrial complexes. And, the core area percentages of landscape gradually decreased and these could possibly deteriorate the soundness of forest areas by reducing the core areas which are habitats of species. In addition, there was intimate relations between ESV and forest landscape area. The results of this study can be detached standards for impartial judgements between the logic of development & conservation, and basic standards for the establishment of development plans, i. e. metropolitan-plans, which are adequately reflected ecosystem value.

• Korean Journal of Environmental Biology
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• v.22 no.1
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• pp.242-245
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• 2004

This study was conducted to assess water quality of Dae stream in Busan using the periphyton. Species of the higher rank 10% in standing crops were Cymbella ventricosa, Aulacoseira granulata, Gomphonema olivaceum, Synedra ulna through the study. In addition, Fragilaria intermedia ill the station 1 and 2, and Nitzschia palea in the station 3 and 4 dominated the periphyton community respectively. These species mainly appeared in the urban stream. Where input of pollutant is forecasted, standing crops of dominant species are investigated very highly. Also, standing crops of Nitzschia palea were higher in the pollution area such as polysaprobic than any other area. Water quality by the saprobic index were oligosaprobic in the station 1, $\beta$-mesosaprobic in the station 2 and 3, and $\alpha$- mesosaprobic in the station 4. These results suggests that the pollution of Dae stream gradually increased with downstream due perhaps to the loading of sewage from the new residental complex.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.4
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• pp.435-447
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• 2019

In order to prevent unnecessary re-admission, it is necessary to intensively manage the groups with high probability of re-admission. For this, it is necessary to develop a re-admission prediction model. Two - year discharge summary data of one university hospital were collected from 2016 to 2017 to develop a predictive model of re-admission. In this case, the re-admitted patients were defined as those who were discharged more than once during the study period. We conducted descriptive statistics and crosstab analysis to identify the characteristics of rehospitalized patients. The re-admission prediction model was developed using logistic regression, neural network, and decision tree. AUC (Area Under Curve) was used for model evaluation. The logistic regression model was selected as the final re-admission predictive model because the AUC was the best at 0.81. The main variables affecting the selected rehospitalization in the logistic regression model were Residental regions, Age, CCS, Charlson Index Score, Discharge Dept., Via ER, LOS, Operation, Sex, Total payment, and Insurance. The model developed in this study was limited to generalization because it was two years data of one hospital. It is necessary to develop a model that can collect and generalize long-term data from various hospitals in the future. Furthermore, it is necessary to develop a model that can predict the re-admission that was not planned.

• Journal of the Korean association of regional geographers
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• v.16 no.3
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• pp.275-294
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• 2010

In recent years, international migration of professional workers is significantly increasing as globalization has been deepened more and more. South Korea is not an exception for this case. Immigration of professional workers have steadily increased since 2000 in Korea, and the number reached approximately to 50,000 in 2009. In addition, it is a major trend that immigrants of short-sojourn are decreasing and ones of long-sojourn increasing. Our research shows that foreign language instructor has the greatest number of foreign professional immigrants. The next is professional immigrants related to business-activities. There are considerably entertainers, but they have greatly decreased since 2003. Majority of foreign professional immigrants settle down in a few metropolises. Especially, they reside in Seoul Metropolitan Area and Southeast coastal region. Professional immigrants trend to do with Korean on the base of their offices rather than residental communities in terms of adaptation, and they do not have strong will to reside permanently in Korea. Moreover, they are located at a blind spot of Korean government's foreign immigrant policy, comparing to foreign workers and female marriage immigrants.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.3
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• pp.346-356
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• 2008

Asbestos is the name of a group of minerals with long and thin fibers that originate naturally in the environment. Asbestos mainly affects lungs and the membrane that surrounds the lungs. In general, PCM (phase contrast microscopy) and PLM (polarized light microscopy) have been used to analyze asbestos fibers. However, these methods have often problems to over-estimate number concentration when counting real asbestos fibers. Moreover, there are many difficulties when separating and identifying various asbestos and non-asbestos fibers. In order to determine quantitative information on fibrous particles, source profiles for asbestos and non-asbestos fibers must be initially developed on the basis of their chemical compositions and physical parameters. In our study, a SEM/EDX was used to develop source profiles from known asbestos samples as reference samples. We could make the source profile matrix consisting of 6 types of asbestos fibers and 2 types of non-asbestos fibers by analyzing 380 fibers. Based on these profiles, a rule building expert system was developed by using the visual basic application (VBA). Various fibers were successfully classified by 2 simple rules in the EXCEL environment based on several visual steps such as inserting data, viewing results, and saving results. For a case study to test the expert system, samples from a construction materials and from various indoor environments such as a residental area, a preschool classroom, and an underground store were collected and analyzed. As a result of the survey, a total of 76 individual test fiber particles was well classified into 5 different types of particle classes; 9.3% of chrysotile, 15.4% of amosite, 0.8 of crocidolite, 4.2% of tremolite, 5.8% glass fiber, 21.1% of other fibers, and 43.5% of unknown fibers in terms of number concentration. Even though unknown portion was high, it will be decreased markedly when expanding fiber source profiles.

• Biomedical Science Letters
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• v.3 no.1
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• pp.37-42
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• 1997

The concentrations in women's hair of essential and toxic elements such as Zn, Ni, Fe, Mn, Cu, Cr, Pb and Cd in residential and factory areas in Pusan were determined, and all the elements were detected from all the samples. It was apparent that employees working in factory areas in Pusan were exposed directly to the essential and toxic heavy matals. This is based on the fact that average concentrations of Ni, Fe, Mn, Cu, Cr, Pb, and Cd in hair samples from women aged 10 to 29 in factory area, who were considered to be main members among women employees, were much higher than those of residential areas. That is, the highest concentrations found in the hair samples taken from women 10 to 29 years old living in factory areas were 110 times higher in Cr (in the women in their 20's), 92 times higher in Pb (in the women in their teens) and 23 times higher in Cd (in the women in their 20's) than those living in residential areas. Furthermore, it was suggested that the heavy metals may be accumulated gradually in human bodies as humans get older, based on the fact that the concentrations of Cr, Pb, and Cd in women living in residential areas were higher in older age groups, although the average contents of these elements in residents from residential areas were similar with those of several foreign countries.

• Korea Science and Art Forum
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• v.19
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• pp.515-525
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• 2015

Along with a rapid increase in the number of 1-person households where the concept of 1-person consumption and 1-person economy is emphasized, the proportion of 1-person household in Korea occupies a 25.3% at present, and the number is expected to grow continuously. And this rapid increase will bring about a host of problems such as housing shortage in the metropolitan area, egoism, loneliness felt by individuals, and other social problems such as crime. As an alternate movement to this phenomenon, concern on and interest in community, community culture, and sharing of space are on the rise, together with concern on and preference for sharehouse culture. In news media as well, articles on life shared with members of a sharehouse often appear. This sharehouse, which is widely spread and well received in Japan, not only reduces economic burden but also creates their own community and promotes their own culture. In this sense, it is a new way of life that represents benefits of sharing, well beyond just economic interests. Accordingly, In this research, an attempt was made tp examine the circumstances in the use of space based on existing studies on sharehouse characteristics in order to shed new lights on the meaning that non-characteristic space concept of the traditional residential space has as the concept of sharehouse space by considering it in connection with the non-characteristic space concept of the Korean traditional residential space where diverse circumstances occur centered on communal life and which were accepted by all naturally.

• 한국노년학
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• v.39 no.1
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• pp.169-188
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• 2019

In this study, the author utilizes longitudinal data of the recent 12 years to verify whether the absolute versus relative income of old age has a significant effect on their life satisfaction of life. The findings of this study show that there is a significant difference in life satisfaction of old age according to respondents' relative income of three reference groups based on their asset quintile and residental area and education. In the correlation analysis using the cross-sectional data, the absolute and relative income level was closely related to the life satisfaction. In the panel regression analysis using the 12 years longitudinal data from the Korea National Labour Panel dataset, the income level of counterparts in those reference groups appeared highly significant in determining the level of life satisfaction of the elderly. However, some demographic variables such as age and marital status did not have a statistically significant effect in the long-term perspective. The income of reference groups in terms of asset levels, education and region as well as their own past life satisfaction level had a significant effect on the elders' life satisfaction determination. These results suggest that the relative income hypothesis in terms of life satisfaction among the elderly is more valid than the previous absolute income hypothesis.