• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.1
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• pp.33-39
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• 1999

In order to understand the importance of tidal action and $NH_4{^+}$ -nitrification in the removal of dissolved oxygen (DO) and $NH_4{^+}$, concentrations of DO, $NH_4{^+}$, $NO_2{^-}$ and $NO_3{^-}$ were measured with time for water samples collected at different tidal state in the eutrophic macrotidal Han River estuary. Field measurements indicated that most environmental parameters, except for the water temperature and DO concentration, were tightly controlled by the eutrophic freshwater runoff and large-scale tidal action. Dark incubation of the water sample at $25^{\circ}C$ showed that the removal rates of DO and $NH_4{^+}$ in high tide sample were 2.76 ${\mu}M\;O_2\;d^{-1}$ and 1.76 ${\mu}M\;N\;d^{-1}$ respectively, and increased to 5.66 ${\mu}M\;O_2\;d^{-1}$ and 3.36 ${\mu}M\;N\;d^{-1}$ respectively, in low tide sample. These changes indicated that microbial degradation and uptake of organic matter and inorganic nutrients were more active during low tide. $NH_4{^+}$-nitrification responsible for total DO removal in low tide (23.81%) and $NH_4{^+}$ turnover rates due to $NH_4{^+}$-nitrification in low tide (0.18 $d^{-1}$) were approximately 3.7 times and 3 times, respectively, higher than those in high tide. These results indicated that $NH_4{^+}$ -nitrifying bacteria introduced into the Han River estuary during low tide played a significant role in the removal of DO and $NH_4{^+}$. The decreasing removal rates in DO and $NH_4{^+}$ with the increasing tidal level seemed to be associated with the salinity impact on the halophobic freshwater $NH_4{^+}$-nitrifying bacteria. The results implied that anthropogenic $NH_4{^+}$ sources should be treated prior to the freshwater runoff into the estuary for the effective control of $NH_4{^+}$ in the Han River estuary. These results also suggest that parallel ecological studies on the chemoautotrophic nitrifying bacteria are essential for the elucidation of nitrogen cycles in the eutrophic Han River estuary.

• Journal of Wetlands Research
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• v.12 no.3
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• pp.1-13
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• 2010

Most of investigations about the effects of dam construction on the surrounding environments have focused mainly on the change of climate conditions and crop production. In order to research the effect of dam construction on the surrounding vegetation, we chose the Soyanggang dam whose storage capacity is the largest in Korea, and was built 33 years ago. We surveyed and analyzed the surrounding vegetation by using quadrat method and measured the soil moisture content among floodplain (FP), 5m above the flood plain (AFP) and control group (CG) which is 3km far from the lake through ridge. The largest value of mean importance percentage of the canopy~understory layer at FP was Salix koreensis (87.9%) and those of AFP and CG was Quercus mongolica (38.9% and 40.4% respectively) and the largest important percentage of the herb layer at FP was Artemisia capillaris (34.2%) and those of AFP and CG was Oplismenus undulatifolius var. undulatifolius (9.4% and 24.6% respectively). The Shannon-Wiener diversity index of shrub~canopy layer at FP (0.26) was lower than AFP (2.34) and CG (2.23) and there was not any significant difference in the herb layer among three groups. The S${\o}$rensen similarity index between FP and AFP, FP and CG was 0, and that of AFP and CG was relatively high. The highest density of tree and subtree with the DBH level of FP was S. koreensis of 5~10cm (240/ha), and that of AFP and CG was Quercus spp. of 15~20cm (400/ha and 466/ha respectively). And the highest density of seedlings of FP was Pinus densiflora (7,040/ha), and that of AFP and CG was Quercus spp. (720/ha and 400/ha respectively). The soil water content of FP (6.28%) was relatively lower than AFP and CG (11.13% and 10.14% respectively; p<.01). These results indicated that construction of Soyanggang dam changed the vegetation of the floodplain, without showing a change in its upland areas.

• Journal of Dairy Science and Biotechnology
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• v.33 no.2
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• pp.129-137
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• 2015

Diabetes mellitus type 2 is a metabolic disorder that is characterized by hyperglycemia (high blood sugar level) in the context of insulin resistance and relative lack of insulin. Recently, much scientific evidence has shown that the risk of diabetes mellitus type 2 could be reduced by dairy intake. A significantly strong relationship has been noted between this disease and dairy intake. In particular, from the different types of fat in dairy foods that were reported to have a beneficial impact, low-fat dairy foods have been found to have the best effect with respect to reducing the risk of diabetes mellitus type 2. Therefore, the role of specific components of dairy foods, such as calcium, vitamin D, dairy fat, and trans-palmitoleic acid, which could be responsible for this effect and for the positive effect of dairy foods in obesity and metabolic syndrome, needs to be identified. There is a strong and relatively consistent body of accumulating evidence indicating that dairy foods may significantly reduce the risk of diabetes mellitus type 2, likely in a dose-response manner. Dairy recommendations should be an essential part of public health guidance, and identifying strategies to increase dairy food consumption to optimal levels is of utmost importance. Hence, this review summarizes various positive effects of dairy foods with respect to reducing the risk of diabetes mellitus type 2, based on available evidence, and discusses the need for further research on preventing or decreasing the risk of diabetes mellitus type 2.

• Korean Journal of Environmental Biology
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• v.19 no.1
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• pp.7-17
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• 2001

Growth optima and tolerance ranges of marine algae species nay vary greatly during the developmental stage. The establishment stage is clearly of great importance for each generation, affecting the performance of the adult population. The present study was aimed to determine the effect of various concentrations of inorganic nutrients and heavy metals on germination and germlings of Ulva pertusa Kjellman (Chlorophyta). Percent germination increased rapidly as irradiance level increased, reaching the maximum at 100 ${\mu}$mol m$\^$-2/s$\^$-1/ in both east and west seawater. Percent germination in the east seawater was higher than that in the west seawater at irradiances lower than 30 ${\mu}$mol m$\^$-2/s$\^$-1/, and there was no difference in percent germination between the two different seawaters at irradiances higher than 60 ${\mu}$mol m$\^$-2/s$\^$-1/. Germling growth increased in the both cases with increasing irradiances but no growth was found in the dark. Overall germling area was larger in the east seawater than in the west seawater. Number of cell increased with increasing irradiance and became light-saturated at 100 ${\mu}$mol m$\^$-2/s$\^$-1/ in the both cases. Germlings grown in the east seawater had more cells than those cultivated in the west seawater at irradiances lower than 60 ${\mu}$mol m$\^$-2/s$\^$-1/. In various combinations of nitrate and phosphate, percent germination increased with increasing nitrate concentrations irrespective of phosphate concentrations. At 3 days after inoculation, nitrate concentration of 2.5 ppm with all phosphate concentrations promoted germination. Area and number of cell of germlings increased with increasing nitrate concentrations in all phosphate concentrations. In various combinations of copper and lead, germination was delayed as copper concentrations increased in all lead concentrations. Percent germination was severely reduced at 1 ppm Cu$\^$2+/. Area and number of cell of germlings decreased with increasing copper concentrations in all lead concentrations. The highest copper concentration (1 ppm) clearly suppressed the germling growth in U. pertusa.

• Journal of the Korean Geographical Society
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• v.29 no.4
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• pp.420-437
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• 1994

The starting point of the research is the relation between capital restructuring and urban restructuring. The economic restructuring, which has been caused by the economic crisis in the early 1970s in the United States has brought a spatial restructuring at different geographic scales. The degree of the success of urban restructuring is contingent to the local economic and political environments. The local contingent factor such as local politics should not be neglected for investigating the restructuring process. Through the case study of Chicago, the research provides two inconsistencies in applying the structural approach to the local level: first, the lack of the theoretical link between crisis and restructuring; and second, the crucial importance of local politics in shaping urban development.

• Journal of the Korean Society of Marine Environment & Safety
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• v.14 no.2
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• pp.135-143
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• 2008

An emergy concept was used to evaluate the environment and economy of the estuarine areas of Yeongsan River, Seomjin River, and Han River in Korea. The emergy evaluations clearly showed ecological and socioeconomic characteristics of the estuarine areas that act as ecological and economic centers of surrounding areas. River, tide, and rain provided most of the renewable emergy inputs to the estuarine areas with their contribution to the total emergy input less than 8%. The estuarine areas mostly relied for their operation on the purchased emergy which accounted for $92{\sim}98%$ of the total emergy input to the systems. Emergy indices such as emergy use per unit area, population carrying capacity, environmental loading ratio, and emergy sustainability index revealed that the estuarine areas of Yeongsan River, Seomjin River, and Han River are not sustainable at the current level of economic activities in the areas. The ecological economic values of the environment of the areas were in the range of $7.29{\sim}22.06$ million Em\/ha/yr. They are more than twice that for the whole country, indicating the ecological and economic importance of the eatuarine areas. It is, therefore, urgent to establish and implement estuarine management policies to protect and restore the ecological and economic potentials of the estuarine areas of Yeongsan River, Seomjin River, and Han River. Management plans for the estuarine areas should include both demand-side measures such as reduction of population and economic concentration and consideration of ecological carrying capacity in planning stages for utilization and development of the areas, and supply-side ones such as restoration of degraded ecosystems and construction of new productive ecosystems.

• Journal of the Korean Chemical Society
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• v.62 no.2
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• pp.124-136
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• 2018

In this study, we applied the flipped-classroom to the general chemistry experiment lecture of the domestic university with strong teacher-led, and explored the effects and possibilities of the course. For this purpose, 30 students who were enrolled in the Science Education Department of the College of Education in the metropolitan area were randomly assigned to two groups, namely, the flipped-classroom group and the traditional class group. Then, we developed a general chemistry experiment lessons based on the flipped-classroom along with visual materials and we applied the lessons for 15 weeks. After all the classes, we conducted a survey to see the students' perception of the general chemistry experiment lecture by flipped classroom. As a result of analysis, the students of the flipped-classroom group were more positive than the students of the traditional class group in terms of the usefulness of the class activity, the importance of each activity element for the successful learning, the learning level, and the intention for another lesson. As a result of analyzing students' perceptions in terms of general chemical experiment activities such as conducting experiments or writing reports and understanding the contents of experiments, the average score of the flippedclassroom group was higher than the traditional class group, and the main cause of this result was the video material provided by prior learning activities. In addition, as a result of analyzing students' perceptions in terms of interactions and self-directed learning in class, the average score of the flipped-classroom group was generally higher than the traditional class group. In particular, students' interactions and self-directed learning were statistically significant differences between the two groups. And the students' perception of video material was very positive, and it was analyzed that the video that the instructor directly explained experiment theory and method was the most favorite videos of students. We discussed educational implications of these findings.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.37 no.3
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• pp.1-12
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• 2019

A bridge is a structure constructed on water or in the air for convenient passage. Compared to other buildings, the building materials and structures of bridge required unique functions to cross the space. It depends on the productivity of the building, the level of science and technology, and the ecological environment of the building site. Also, it has important relationship with functions such as politics, military, economy, and life. Most of the academic research on bridges is focused on research in the field of bridge-building technology, so the study on the landscape aesthetics and history of bridges is lacking. Against this backdrop, the study will be valuable as a accumulation of both countries' understanding of bridge types, history and culture, as well as technical and aesthetic data, by analyzing the bridges located within the palaces of Korea and China. The research method is to analyze the bridge through field survey and literature analysis.. First, the bridges of royal palace of Korea and China are to be classified quantitatively as physical shapes, landscapes, and decorations by comparing the materials, forms, landscapes, and decorative culture of bridges. Second, characteristics, common points, and differences are extracted by classifying bridges of both countries. Also, the results are discussed based on the physical environment or cultural background. This would be worth cross-referencing in the building technology and aesthetics of the two countries. For the first important characteristics of result, main materials of Korean and Chinese palaces are stone. However, the bridge in China's royal palaces is also focused on wood. Second, in terms of form, the bridges in the royal gardens of Korea and China are all based on the beam bridge. However, the specific form, ratio, style of the beam bridge, and airspace of arched bridge are very different. Third, most of the connection methods are focused on the over bridge. It values the convergence with the surrounding landscape. Due to the difference in the area and location of water, the bridge in the Korean palace is more focused on the convergence of the surrounding buildings and plants, while the bridge in the Chinese palace is more concerned about the harmony of hydration. Fourth, the decoration places importance on the artistry and aesthetics of both the bridges in Korea and China. There is a difference in style in the same type of decoration due to culture.

• Journal of the Korean Society of Food Science and Nutrition
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• v.8 no.1
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• pp.51-62
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• 1979

Due to the relatively high number of members and low income in each family, Wido inhabitants take very low nutrition. The result indicates that nutrition at the present time is generally lower than that of 1973 with the exception of fat. Consequently, the degree of body development of primary and junior high school students has not generally reached the standard in Korea, that was collected from Gyeongido, Korea and from Japan, of the corresponding grade students as well as the Hb content is significantly insufficient. As the body development of 12-year-old children grown at home and nursery, and attending the sports school are compared with that of the Korean standard and Wido students, the body development of Wido students is similar to the Korean standard, and slighly better than that of the sports school students by three years. Health is important as said that health power is nation's power. In order to maintain good health, the normal level of body development and Hb content is necessary for which the recommended daily nutrition for each person should be taken. In addition, the present status and importance of body development and nutrition should be fully educated the primary and junior high school students as well as directly to the inhabitants.

• Journal of Korean Home Economics Education Association
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• v.18 no.3 s.41
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• pp.97-117
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• 2006

The purpose of this study was to investigate the teachers' recognition on the optimization of the educational contents of Clothing & Textiles in subjects of :he Practical Arts or the Technology & Home Economics in the course of elementary, middle and high schools. The statistical data for this research were collected from 203 questionnaires of teachers who work on elementary, middle and high schools. Mean. standard deviation, percentage were calculated using SPSS/WIN 12.0 program. Also. these materials were verified by t-test, One-way ANOVA and post verification Duncan. The results were as follows; First, The equipment ratio of practice laboratory were about 24% and very poor in elementary schools but those of middle and high school were 97% and 78% each and higher than elementary schools. Second, More than 50% of teachers recognized the amount of learning 'proper'. The elementary school teachers recognized the mount of learning in 'operating sewing machines' too heavy especially, the same as middle school teachers in 'making shorts': the same as high school teachers in 'making tablecloth and curtain' and 'making pillow cover or bag'. Third, All of the elementary, middle and high school teachers recognized the levels of total contents of clothing and textiles 'common'. The 80% of elementary school teachers recognized 'operating sewing machines' and 'making cushions' difficult especially. The same as middle school teachers in 'hand knitting handbag by crochet hoop needle', 'the various kinds of cloth' and 'making short pants'. The same as high school teachers in 'making tablecloth or curtain'. Fourth, Elementary school teachers recognized 'practicing basic hand needlework' and 'making pouch using hand needlework' important in the degree of educational contents importance. Middle school teachers recognized 'making short pants unimportant. High school teachers considered the contents focusing on practice such as 'making tablecloth and curtain' and 'making pillow cover or bags' unimportant. My suggestions were as follows; Both laboratories and facilities for practice should be established for making clothing and textiles lessons effective in Practical Arts in elementary schools. The 'operating sewing machines' which were considered difficult should be dealt in upper grade, re-conditioning to easier or omitted. The practical contents should be changed to student-activity-oriented and should be recomposed in order to familiar with students' living. It was needed to various and sufficient supports for increasing the teachers' practical abilities.