• Journal of Korea Water Resources Association
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• v.53 no.2
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• pp.107-119
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• 2020

This study analyzed past drought characteristics based on the observed rainfall data and performed a long-term outlook for future extreme droughts using Representative Concentration Pathways 8.5 (RCP 8.5) climate change scenarios. Standardized Precipitation Index (SPI) used duration of 1, 3, 6, 9 and 12 months, a meteorological drought index, was applied for quantitative drought analysis. A single long-term time series was constructed by combining daily rainfall observation data and RCP scenario. The constructed data was used as SPI input factors for each different duration. For the analysis of meteorological drought observed relatively long-term since 1954 in Korea, 12 rainfall stations were selected and applied 10 general circulation models (GCM) at the same point. In order to analyze drought characteristics according to climate change, trend analysis and clustering were performed. For non-stationary frequency analysis using sampling technique, we adopted the technique DEMC that combines Bayesian-based differential evolution ("DE") and Markov chain Monte Carlo ("MCMC"). A non-stationary drought frequency analysis was used to derive Severity-Duration-Frequency (SDF) curves for the 12 locations. A quantitative outlook for future droughts was carried out by deriving SDF curves with long-term hydrologic data assuming non-stationarity, and by quantitatively identifying potential drought risks. As a result of performing cluster analysis to identify the spatial characteristics, it was analyzed that there is a high risk of drought in the future in Jeonju, Gwangju, Yeosun, Mokpo, and Chupyeongryeong except Jeju corresponding to Zone 1-2, 2, and 3-2. They could be efficiently utilized in future drought management policies.

• Korean Journal of Medicinal Crop Science
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• v.16 no.5
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• pp.356-370
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• 2008

This study was conducted for screening on antioxidant activity of 429 plants and selecting new potential antioxidant candidates. In vitro test models such as scavenging activity on DPPH radical and inhibitory activity on linoleic acid oxidation were used in the preliminary study. Flower of Sanguisorba officinalis, flower of Sedum kamtschaticum, flower of Rumex obtusifolius, and root of Sedum kamtschaticum showed very effective antioxidant activity on DPPH radical and linoleic acid oxidation. Those plants showed 8.1, 9.4, 9.9, $11{\mu}g/ml$ in DPPH radical scavenging activity as $SC_{50}$ and did 80.4, 80.1, 84.5, 88.0% in inhibition activity on linoleic acid oxidation, respectively. Root of Sedum middendorfianum M. showed positive effects in superoxide radical scavenging activity ($38.4{\mu}g/ml$) and inhibitory effect on $CuSO_4$-induced LDL oxidation (53.8% at final concentration of $1{\mu}g/ml$). Gleditsia japonica Mig. showed high antioxidant activity on LDL oxidation as 71.6% at final concentration of $1{\mu}g/ml$ and total phenol content of 958.5 mg% as tannic acid equivalent. In conclusion, we think that these plants having potent antioxidant activity might be studied further and could be used as new resources for many purposes including healthy food, functional cosmetics and drug development etc.

• Journal of the Mineralogical Society of Korea
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• v.29 no.2
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• pp.59-71
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• 2016

To investigate the sorption characteristics of Cs, which is one of the major isotopes of nuclear waste, on natural zeolite chabazite, XRD, EPMA, EC, pH, and ICP analysis were performed to obtain the informations on chemical composition, cation exchange capacity, sorption kinetics and isotherm of chabazite as well as competitive adsorption with other cations ($Li^+$, $Na^+$, $K^+$, $Rb^+$, $Sr^{2+}$). The chabazite used in this experiment has chemical composition of $Ca_{1.15}Na_{0.99}K_{1.20}Mg_{0.01}Ba_{0.16}Al_{4.79}Si_{7.21}O_{24}$ and its Si/Al ratio and cation exchange capacity (CEC) were 1.50 and 238.1 meq/100 g, respectively. Using the adsorption data at different times and concentrations, pseudo-second order and Freundlich isotherm equation were the most adequate ones for kinetic and isotherm models, indicating that there are multi sorption layers with more than two layers, and the sorption capacity was estimated by the derived constant from those equations. We also observed that equivalent molar fractions of Cs exchanged in chabazite were different depending on the ionic species from competitive ion exchange experiment. The selectivity sequence of Cs in chabazite with other cations in solution was in the order of $Na^+$, $Li^+$, $Sr^{2+}$, $K^+$ and $Rb^+$ which seems to be related to the hydrated diameters of those caions. When the exchange equilibrium relationship of Cs with other cations were plotted by Kielland plot, $Sr^{2+}$ showed the highest selectivity followed by $Na^+$, $Li^+$, $K^+$, $Rb^+$ and Cs showed positive values with all cations. Equilibrium constants from Kielland plot, which can explain thermodynamics and reaction kinetics for ionic exchange condition, suggest that chabazite has a higher preference for Cs in pores when it exists with $Sr^{2+}$ in solution, which is supposed to be due to the different hydration diameters of cations. Our rsults show that the high selectivity of Cs on chabazite can be used for the selective exchange of Cs in the water contaminated by radioactive nuclei.

• Journal of Oral Medicine and Pain
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• v.36 no.4
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• pp.261-271
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• 2011

Osteoarthritis in patients with temporomandibular disorders(TMDs) induces pain, limitation of mouth opening, occlusal problems, and most commonly affects their life quality. Control method and progressive process of osteoarthritis are being extensively researched. The researchers focus on histologic changes, synovial changes, muscular and ligamental changes and observed reaction to pain. Therefore most of them developed the animal model for osteoarthritis in TMD patients. In this study, we applied several methods which induces osteoarthritis of temporomandibular joint(TMJ) in rats or mice. For locally induce osteoarthritis in TMJ, Monosodium iodoacetate(MIA) or interleukin-$1{\alpha}$(IL-$1{\alpha}$) were injected into TMJ joint space for 5 or 3 weeks. Other groups are chosen for osteoarthritis under systemic control including hormonal changes and aging. To observe cellular change, increased collagen, degenerative bony destruction and distribution of proteoglycans (PGs), safranin-O staining and Masson's trichrome staining were used.

• Journal of dental hygiene science
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• v.16 no.3
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• pp.225-234
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• 2016

The purpose of this study was to determine the oral health condition and behavioral status of Korean adults according to occupational status. The subjects were 7,676 adults, aged between 19 and 64 years, who completed both oral examination and questionnaire survey, among those who indicated that they were currently participating in economic activities, according to the data from the Fourth Korea National Health and Nutrition Examination Survey. Occupational class and employment status were selected as measures of occupational status. Complex-samples logistic regression models were used to assess the associations among oral health, behavioral, and occupational statuses. We found a significant occupational class-related difference in the oral health and behavioral statuses of both the men and women. In particular, the prevalence odds ratios of untreated dental caries in manual workers were 1.19 and 1.67 times higher than in non-manual workers, for men and women, respectively. As for oral health condition and behavioral status according to employment status, the health risk in temporary employment workers was higher than that in permanent employment workers. As for the prevalence odds ratios of the risk of dental caries, the highest values were observed for tooth brushing fewer than 3 times per day, not undergoing oral examinations, and chewing difficulty complaints. The risk of dental caries for agricultural, forestry, and fishing workers for both men and women was found to be the highest among other workers. Thus, strategies to promote workplace oral health in the microscopic and macroscopic perspectives should be developed to constantly monitor oral health problems, and to identify vulnerable social groups within occupational groups and the related factors that mediate oral health differences.

• Geophysics and Geophysical Exploration
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• v.9 no.1
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• pp.129-138
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• 2006

Helicopter-borne aeromagnetic surveys at two different times separated by three years were conducted to better understand the shallow subsurface structure of the Vulcano and Lipari volcanic complex, Aeolian Islands, southern Italy, and also to monitor the volcanic activity of the area. As there was no meaningful difference between the two magnetic datasets to imply an apparent change of the volcanic activity, the datasets were merged to produce an aeromagnetic map with wider coverage than was given by a single dataset. Apparent magnetisation intensity mapping was applied to terrain-corrected magnetic anomalies, and showed local magnetisation highs in and around Fossa Cone, suggesting heterogeneity of the cone. Magnetic modelling was conducted for three of those magnetisation highs. Each model implied the presence of concealed volcanic products overlain by pyroclastic rocks from the Fossa crater. The model for the Fossa crater area suggests a buried trachytic lava flow on the southern edge of the present crater. The magnetic model at Forgia Vecchia suggests that phreatic cones can be interpreted as resulting from a concealed eruptive centre, with thick latitic lavas that fill up Fossa Caldera. However, the distribution of lavas seems to be limited to a smaller area than was expected from drilling results. This can be explained partly by alteration of the lavas by intense hydrothermal activity, as seen at geothermal areas close to Porto Levante. The magnetic model at the north-eastern Fossa Cone implies that thick lavas accumulated as another eruption centre in the early stage of the activity of Fossa. Recent geoelectric surveys showed high-resistivity zones in the areas of the last two magnetic models.

• Journal of the Korean Geographical Society
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• v.41 no.1 s.112
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• pp.106-120
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• 2006

Natural or man-made disaster has been expected to be one of the potential themes that can integrate human geography and physical geography. Typhoons like Rusa and Maemi caused great loss to insurance companies as well as public sectors. We have implemented a natural disaster management system for a private insurance company to produce better estimation of hazards from high wind as well as calculate vulnerability of damage. Climatic gauge sites and addresses of contract's objects were geo-coded and the pressure values along all the typhoon tracks were vectorized into line objects. National GIS topog raphic maps with scale of 1: 5,000 were updated into base maps and digital elevation model with 30 meter space and land cover maps were used for reflecting roughness of land to wind velocity. All the data are converted to grid coverage with $1km{\times}1km$. Vulnerability curve of Munich Re was ad opted, and preprocessor and postprocessor of wind velocity model was implemented. Overlapping the location of contracts on the grid value coverage can show the relative risk, with given scenario. The wind velocities calculated by the model were compared with observed value (average $R^2=0.68$). The calibration of wind speed models was done by dropping two climatic gauge data, which enhanced $R^2$ values. The comparison of calculated loss with actual historical loss of the insurance company showed both underestimation and overestimation. This system enables the company to have quantitative data for optimizing the re-insurance ratio, to have a plan to allocate enterprise resources and to upgrade the international creditability of the company. A flood model, storm surge model and flash flood model are being added, at last, combined disaster vulnerability will be calculated for a total disaster management system.

• Journal of Korean Home Economics Education Association
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• v.28 no.1
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• pp.19-39
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• 2016

The purpose of this study was to develop the safety theme-based integrated teaching learning process plans for the middle school Home Economics(HE) Instruction and ultimately to contribute for the middle school students to live their safe lives. To achieve the goals of this study, HE curriculum documents from the 1st to the 2015 revision were analyzed and a survey was conducted to identify the middle school students' current status of safety accidents and needs on the HE safety education. The respondents of the survey were the 512 students of one ${\bigcirc}{\bigcirc}$ Girls' Middle School in Busan. And then, the seven integrated themes were selected, each seven integrated theme-networks were formed, and safety theme-based Home Economics curriculum and learning materials were developed. The results of this study were as the follows. The safety education content has continually been included from the first HE curriculum of 1954 to the 2015 revised HE curriculum. The middle school student respondents highly needed the content of 'the methods to deal with sexual violence and prostitution prevention', 'suicide prevention', and 'bullying net' for the HE safety education. All the 42 items were needed for the HE safety education by the respondents. The safety theme-based HE teaching learning process plans developed finally included the seven integrated themes, which were (1) dietary life safety, (2) adolescents' sex and safety, (3) adolescents' relationships with friends and safety, (4) family life and safety, (5) dwelling life and safety, (6) adolescents' egos and safety, and (7) social environment and safety. Each integrated theme consisted of three to six small themes, which amounted to total 28(for 35 lessons). Each small theme was presented with learning objectives and particular goals. The total 157 learning materials including the Home Economics curriculum were developed, which offered learning objectives and content for each safety theme, total 28 teaching and learning plans(for 35 lessons) were developed, which offered specific instructions for the easy implementation of the curriculum in the classroom, 28 PPTs, 25 film materials, four reading materials, 61 workbooks, 14 activity sheets, 16 evaluation sheets, 3 test sheets, 2 reference materials, and 4 learning material models(the refrigerator model, traffic lights for discussions, food tray model and stickers, and food mileage card). In this study, the safety education themes of 'clothing life and safety', 'conflict and safety', 'professional life and safety', and 'consumer and safety' were not addressed because these theme were not needed highly by the respondents. Therefore, for the further development of the teaching learning process plans for the HE safety education, it is necessary to develop and evaluate the teaching learning process plans to address the themes of 'clothing life and safety', 'conflict and safety', 'professional life and safety', and 'consumer and safety'.

• Korean Journal of Health Education and Promotion
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• v.5 no.2
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• pp.26-40
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• 1988

This survey was conducted to find out the present status of health education program being provided in primary schools focusing its planning, operation, contents and attitude of school nurses in September, 1988. Total 413 school nurses who are presently working in Seoul city was surveyed by mail and 167 school nurses who responded to the questionnaire were finally ana lysed. The following results were obtained. 1. The general charcteristics of the school nurses′ surveyed. As for age distribution, 30-40 age group was 60.4％ the highest and the mean age was 30. 13. As for educational attainment, junior nursing college was 71.9％. 68.3％ of the surveyed was married and 43.1％ of them has 5-10 years of working experiences. As for schools where school nurses are presently working, 31.7％ has 2,000-3,000 students, 22.8％ has 50-60 classes and 5 schools have more than 80 classes. 2. Planning of a school health education School health education was planned every semester in 55.7％, which was the highest. As for utilization status of the materials for planning of a school health education as a referance, 86.8％ of the total respondants utilized the guidelines published by Seoul city School nurses′ Association, and the administrative guidelines for school health, textbooks, school health statistics and articles related to school health in order. It was tried whether the number of referances being utilized was related to the working experiences. It was found that the shorter the experiances, the more materials were utilized. It was answered that teaching plan for health education was prepared by school-nurses themselves (95.2％), and was differentiated as three levels as the first and second grades, the third and fourth grades, and the fifth and sixth grades 3. The contents of the school health education 16 subjects offered to 6 grades of students were surveyed as follows. As for fifth and sixth grades, contents on growth and development was most widely provided as 54.5％, and 68.9％, respectively. And the next to this subject, dental health education was also frequently offered to the second, third and fourth grades as 50.9％, 68.9％, and 47.3％, respctively. 4. The operation of school health education Health education provided by school nurses was conducted formallu in 36.6％, and formally of informally accordin to grades in 43.9％. It was answered that 50.3％ of the surveyed school had started health education from 1987, when the plan for activation of school health was ordered from. Educational Committee. Teaching hours of school nurses was 6 in 32.9％, which was the highest. The lesson was provided for class unit in 77.2％, and sex education was sometimes offered to male and female students separately. As for support of health personnels out of school for health education, 79.0％ did not receive any support. If there were any aids out of school, 62.9％ received them from other related agencies and 74.3％ anwered that it was once in a semester. As for expenses for health education, 57.3％ did not input any expenses alloted to school health program as a whole. As audio-visual materials, slides were utulized most frequently and models, and charts in order. 5. Awareness of school nurses on the operation of school health education School nurses evaluated their educational quality as a health educator subjectively, 60-70％ of them answered to be average in 4 domains such as knowledge, educational skill, ability to prepare teaching plan, and cooperation. As for the awareness on the support and cooperation of the higher institutions, 46.4％ -61.8％ answered that "so and so" toward Ministry of Education and Ministry of Affairs, and 13-37％ "not supportive" Teachers of the corresponding schools were answered to be "so and so" in 55.9％-56.7％, and "very supportive" in 33.34％. There was a significant difference in formality of the lesson according to the support of the superintendent.

• The Korean Journal of Ecology
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• v.28 no.3
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• pp.149-156
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• 2005

This study was conducted to elucidate the relationship between the aboveground vegetation structure and fine roots of the topsoil (<15m), and thereafter to obtain the regression models for the estimation of the fine roots of the topsoil using the aboveground vegetation values in the burned forest areas, Korea. The FRT (fine roots of the top soil) as well as the aboveground vegetation structure showed spatial variation in the earlier successional stages after forest fire. The fine roots (<2 mm) of the topsoil in the earlier successional stages than the first 3 year after forest fire showed the range from 3 to 166 g $DM/m^2$. The FRT in the naturally regenerated sites and planted sites after forest fire was closely correlated with the vegetation indices, especially lvc, representing the development status of the aboveground vegetation. The FRT in the terrace seeding work sites after forest fire was closely correlated with year elapsed after terrace seeding work. The FRT in the terrace seeding work sites showed the much higher values because of the vigorous growth of grass species than the other sites. In the naturally regenerated sites, the FRT showed the parabola form according to the increment of aboveground vegetation value (Ivc). Although the aboveground vegetation value (Ivc) showed a tendency to increase logarithmically during the secondary succession after forest fire, the estimated fine roots of the topsoil was depicted the parabola form showing the gradual increment until the first 15 years and slight decrease thereafter. Decrease of FRT in the later successional stage showing the high vegetation value may be caused by increment of the woody species contribution to the vegetation value (Ivc). Our results represented that the aboveground vegetation value (Ivc) can be used to the estimation of the fine roots of the topsoil in burned forest areas.