• Journal of Korean Society on Water Environment
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• v.34 no.3
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• pp.285-292
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• 2018

This study was performed in order to identify the red tide-causing organism and to understand the characteristics of the water quality during the winter of 2015 and 2016 in the Oncheon stream, a tidal river in Busan, where red tide often occurs in the wintertime. Two sites were selected on the stream and the surface water was sampled a total of 28 times during the experimental period. Twelve water quality characteristics, including water temperature, pH, DO, COD, total-N (T-N), total-P (T-P), and salinity were analyzed in order to test water quality. The cell numbers of cryptomonads were counted directly by microscopic observation. The nucleotide sequences of the partial 28S rRNA gene and psbA gene from metagenomic DNA, derived from each sampling site, were analyzed. According to the results, the alga most responsible for the bloom was identified as Teleaulax OC1 sp., which belongs to the cryptomonads. Three items of chl-a, pH, and DO were positively correlated with the cell numbers of the cryptomonads counted at the upper stream of the tidal area (St 1) while eight items of chl-a, TOC, BOD, total-N, COD, SS, pH, and DO were positively correlated with the cells located at the junction between the stream and Su-young river (St 2) in the order.

• Journal of Gifted/Talented Education
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• v.18 no.1
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• pp.79-109
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• 2008

In most curricular model for gifted children, independent study is included as an important element for developing students' study ability and producing creative production Gifted children also prefers this style of learning and they study more easily and with more fun when they learn in the learning style they prefer. This study aims to find out how gifted children in math area performs independent study and how teachers who teach them recognize independent study; survey study was used to analyze the reality of the production in relation to independent study. In result, gifted children's independent study ability was rather very low and teachers recognized the necessity of independent study but lacked understanding of the method of independent study.

• Korean journal of food and cookery science
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• v.32 no.6
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• pp.818-827
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• 2016

Purpose: This study was conducted to investigate the effect of freeze-dried Gastrodiae rhizoma powder (GR) on the liver function and alcohol metabolism in alcohol treated rats. Methods: The rats were administered various concentrations of GR (100 mg, 200 mg, 300 mg/kg B.W.) for 3 days 1 hour before 50% (v/v) ethanol (3 g/kg B.W.) administration. Two tests focusing on liver function and alcohol metabolism in acute alcohol treatment were carried out. Results: Glutamic oxaloacetic transaminase activity was significantly increased by alcohol treatment, and was decreased by 100 mg GR administration. Acute ethanol treatment led to significant increase in alcohol and acetaldehyde levels of serum and liver. However, 100 mg GR administration led to a significant reduction in increased alcohol level in the serum with decreased alcohol dehydrogenase (ADH) activity and increased acetaldehyde level in liver was significantly reduced by three levels. Conclusion: These results suggest that GR can be effective in enhancing liver function and alcohol metabolism in the alcohol-treated rats. Studies on the appropriate dosage of GR should further be developed to treat alcohol detoxification and stimulate liver function.

• Korean Journal of Materials Research
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• v.1 no.4
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• pp.184-190
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• 1991

Oxygen chemisorption on single crystal ZrC(111) surface was studied by high-resolution electron energy loss and ultraviolet photoelectron spectroscopy. At a low amount of oxygen exposure, adsorbed oxygen atoms construct $(\sqrt{3}{\times}\sqrt{3})R30^{\circ}$ structure. On the other hand, oxygen adsorption changes into $1{\times}1$ structure as the amount of oxygen exposure increases. The adsorbed oxygen atoms show smaller vertical distance from the Zr topmost layer in the $1{\times}1$ structure than in the $(\sqrt{3}{\times}\sqrt{3})R30^{\circ}$ structure and approach to the bridge site rather than 3-fold hollow site. The two different oxygen adsorption behavior comes from the two different surface stales of the clean ZrC(111) surface.

• Korean Journal of Materials Research
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• v.6 no.7
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• pp.716-722
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• 1996

Effect of Film thickness on the sensing behavior of thin-film-type ags sensor has been analyzed by deriving an equation form a simple model, and the equation was applied to the sensing behavior of ${SnO}_{2}$ and CuO-${SnO}_{2}$ thin-film sensors. It was revealed, from the equation,that the gas sensing property was closely related to gas diffusivity into the film which was a function of film thickness, reactivity of the gas detected with sensing material, operating temperature, etc. The equation derived was well consistent with the experimental results from ${SnO}_{2}$ and CuO-${SnO}_{2}$ thin-film sensors and explained their different ${H}_{2}S$ sensing behaviors. Finally, a medel was suggested, explainning the effect of gas diffusivity on sensing be havior of oxide semiconductor sensor.

• Journal of the Korean Society of Clothing and Textiles
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• v.12 no.2 s.27
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• pp.237-248
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• 1988

To access the appropriate height of sleeve cap which is required for the basic sleeve pattern according to arm movements, plaster gypsum experiment was performed. Arm movements were 5types ($0^{\circ},\;45^{\circ},\;90^{\circ},\;135^{\circ},\;180^{\circ}$) to the vertical directions in the front. The appropriateness of the pattern was analyzed by measuring clothing pressure. The results obtained were as follows: 1. Increasing the movement angle, sleeve width increased but height of sleeve cap and armhole girth decreased. 2. Increasing the movement angle, the acromion moved to the front part of bodice. 3. On the basis of the result of the height of sleeve cap, the $\frac{AH}{4} +2.5cm$ sleeve basic 4 pattern is suitable for the direction $M_1(0^{\circ}),\;M_2(45^{\circ})$, and the $\frac{AH}{5}$sleeve basic pattern is suitable for the direction $M_3(90^{\circ}),\;M_4(135^{\circ})$, and $M_5(180^{\circ})$. 4. As the movement angle and height of sleevecap increased, the part which receive high pressure increased and the difference between the hightest and the lowest clothing pressure increased. 5. By the variation of movement angle and height of sleevecap, clothing pressure of upperarm was affected more than that of shoulder blade. 6. The clothing pressure of upperarm and shoulder blades were more affected by the height of sleeve cap than the ease of breast area. 7. Considering the clothing pressure of various arm movement, the most appropriate height of sleeve cap for $M_1(0^{\circ}),\;M_2(45^{\circ})$ positions was to use the $\frac{AH}{4}$+2.5cm, and for $M_3(90^{\circ}),\;M_4(135^{\circ})$, and $M_5(180^{\circ})$, was $\frac{AH}{5}$.

• Applied Chemistry for Engineering
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• v.18 no.5
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• pp.407-414
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• 2007

Using the MPI (Moldflow Plastics Insight) software from Moldflow Co., the optimum conditions for producing the upper part of the automobile air cleaner were obtained for 20% talc filled polypropylene (PP). The analysis was carried out to solve the cracking problem between upper and lower parts and the improved process was proposed using the flow balance. The comparative results between the conventional process, CASE-1, with one-pin gate and the new process (CASE-2) comprising two-pin gate system are the followings. In the case of CASE-2, the shorter filling time and reduced cycle time induced an improved production and processibility. In addition, the orientation and volumetric shrinkage are similar to those observed in the lower part, but the assembly, deformation, and physical characteristics are enhanced. The problem induced by the CASE-1 did not originate from the residual stress, but from the difference in the size of the upper part air cleaner after shrinkage. Thus, the orientation problem was expected to improve by optimizing the gate structure.

• Journal of Korean Home Economics Education Association
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• v.12 no.3
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• pp.65-76
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• 2000

Comparative Study on Historical Changes of Practical Arts Education and Technology-Home Economics Education in Korea and Japan This dissertation is a comparative study on Practical Arts(Home Economics) Education and Technology-Home Economics Education of Korea and Japan. I established two research objectives to conduct the research : To understand the differences in historical changes in Practical Arts Education and Technology-Home Economics of the two countries: And to grope for the new direction of Home Economics Education. Research findings are as follows : Japan was also ahead of Korea for about two decades in terms of putting Home Economics Education in practice at elementary schools. Practical Arts Education Started to emerge in Elementary school system in 1955, which had been originated in vocational education before the year 1945 in Korean However, from the 3th curriculum Practical Arts Education Curriculum put emphasis on home lives. Regarding the characteristics of education from the perspectives of historical changes at Korean Junior-high schools after the year 1945. Home Economics Education had been regarded as “female subject”until the 1980s and was integrated into regular curricula for co-education in the middle of the 1990s. when the 6th Curriculum was activated. Technology-Home Economics started to emerge in Japan in 1962. while the subject Home Economics Education was integrated into curricula for males in high school as well in 1989. In the Korean 7th Curriculum, the combined subject Technology-Home Economics is divided into three categories. A remarkable difference from japanese Technology-Home Economics is that korean curriculum has no division between required and elective. In conclusion. I observe that both Korean and Japanese curricula for Home Economics Education were originated in Confucianism. However, unlike Korean situation, current Japanese Home Economics Education takes a significant part as a continuing and required subject for both primary and secondary co-education.

• Journal of The Korean Association For Science Education
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• v.17 no.4
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• pp.451-460
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• 1997

Various modern social problems are also related with science and technology. Thorough understanding about Technology-Society(STS) interactions is required to take informed action about how to deal effectively with these problems. In this case, there is a need for STS education. The purpose of this study was to examine the perceptions of high -school students and science teachers about Technology-Society interactions and differences of their perceptions. It is my hope that this thesis will contribute to future "General Science" class in Korea. We obtained the data by a survey of 414 high school students who took "General Science" courses in Seoul and 54 of their science teachers. The survey was made using 10 multiple-choice items selected from the VOSTS (Views On Science-Technology-Society) item pool. The results of this study are as follow: 1. More than half of the students and teachers thought that science is exploring the unknown and discovering new things. Their perceptions about the science are somewhat stable, but about the technology various. 2. Most students and teachers thought that science and technology interact and complement each other. They also thought that the improvement in the quality of life needs investments in both science and technology 3. Most students and teachers thought social facts as community, government, and politics influenced scientists and scientific research. They also had a good understanding about the effects of science and technology on society. We can conclude from this that they had a Science-Technology-Society oriented viewpoint. 4. There are significant differences between the perceptions of boys and girls in following categories (p<.05): Influence of Community or Government Agencies on Scientists Influence of Politics on Scientists Role of Scieoce/Technology in Resolving Social Problems 5. There are significant differences between the perceptions of students and teachers in following categories (p<.05): Definition of Science Influence of Politics on Scientists

• Journal of The Korean Association For Science Education
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• v.15 no.3
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• pp.325-331
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• 1995

The purpose of this study is to analyze learning objectives of biology contents in SATIS 14-16. Modified the 5th NAEP three dimentional science assessment framework was used to analyze learning objectives of SATIS 14-16. This study will be a basic data for the development of STS programs in KOREA. The following results were obtained. 1. In a content dimension, 'structures and functions of organism'(63.9%) was the most frequently found, followed by 'the nature and our Iives'(22.1%), 'a continuity of Iife'(9.4%) and 'our surrounding Iives'(4.7%). 2. In a cognitive dimension, an understanding of scientific knowledge(32.7%) was the most frequently found, followed by an improvement of inquiry ability(25.6%), attitude(24.7%), and scientific knowledge and its application(17.0%). 3. In a context dimension, a personal context(32.8%) was the most frequently found, followed by a social context(27.3%), a scientific context(20.0%) and a technological context(20.0%). 4. There were some differences in behavior when each content was compared. In 'surrounding lives' and 'a continuity of life', an understanding of scientific knowledge was the most frequently found. In 'structures and functions of organism' and 'the nature and our lives', proportions of four behavioral catagories were relatively even. 5. There were some differences in context when each content was compared. In 'surrounding lives', scientific context was the most frequently found, whereas in 'structures and functions of lives', individual context was found the most frequently. In 'a continuity of life', scientific and social context were found more frequently than others. In 'the nature and our lives', social context was the most frequent one.