• Journal of the Society of Cosmetic Scientists of Korea
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• v.35 no.2
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• pp.79-89
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• 2009

The objective of this study was to find out the stable formulation of nano-emulsion containing high concentration of quercetin and to investigate the effect of an ethanol on the nano-emulsion prepared by POE (30) hydrogenated castor oil (HCO-30)/oil/quercetin/ethanol/water system. Nano-emulsion was prepared using emulsion inversion point (EIP) method as low-energy method plus homogenizer as high-energy method. To evaluate effect of ethanol and other components on the nano-emulsion, physical properties such as droplet size, morphology, and size distribution were determined. The optimal quercetin concentration was 0.2 % on the nano-emulsion. The droplet diameter was below 300 nm at the HCO-30 concentration below 2.00 %. Nano-emmulsion containing 4.75 % HCO-30 was the most stable and its mean droplet size was 172.40 nm. Finally, the size of nano-emulsion containing 4.00 % ethanol was 128.15 nm and size distribution was also narrow. The results showed that the breakdown process of this nano-emulsion could be attributed to Ostwald ripening. This study about effect of ethanol on the nano-emulsion showed that loading capacity of drug could be increased by using a small amount of ethanol. As prepared stable nano-emulsion, this study showed that these results could be applied to pharmaceutics, cosmetic including skin-care products, perfume and etc.

• Journal of Science Education
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• v.43 no.3
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• pp.363-381
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• 2019

This study aims to suggest an inclusive conceptual framework for the Nature of Technology (NOT) by examining literature and researches regarding NOT and then to analyze the conceptions of the students in Science and Engineering Department of a college based on the NOT framework. Findings are as follows: First, the conceptual framework of the NOT developed from the study has the five domains of NOT, which are Technology as Artifacts, Technology as Knowledge, Technology as Practice, Technology as History, and Technology as a part of Society. Second, the participants' conceptions of the NOT emphasize on three domains of the Technology as Practice (26.4%), Technology as a part of Society (25.8%), and Technology as Knowledge (24.3%) among the five domains of the NOT. Third, according to the microanalysis of the students' conceptions regarding NOT, students in Science and Engineering Department of a college possess concrete and various views of the NOT even though NOT is abstract and complex ideas. Specifically, they seem to recognize the NOT as a product of process and ability to utilize the technology for convenience of life.

• Journal of the Korean earth science society
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• v.21 no.4
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• pp.398-407
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• 2000

We investigated people's patterns of reasoning regarding the Korean traditional interpretation of Planet Occultation by the Moon. A questionnaire survey was administered to the sample which consisted of 632 participants: middle school students(n=164), high school students(n=157), university students(n=172), and the public(n=139). It was revealed that 15.7% of the participants agreed, 38.1% disagreed, and 46.2% were neutral to the traditional interpretation. A comparatively large portion of the university students made a scientifically correct judgement by disagreeing with the traditional interpretation. On the other hand, a relatively small proportion of the middle school students disagreed. Participants' views of nature and views of science were the major reasons for making their judgements. Most participants were fixed with similar views to the Korean traditional view of nature. Most of the participants valued using more extensive evidence and experimental proofs in science. High school and university students considered their metaphysical beliefs, such as view of nature and view of science, more important than other groups did. In contrast to this, middle school students and the public depended more strongly on their personal experiences. Participants' social experiences and their scientific knowledge were also important reasons for making their judgement. However the differences in their scientific knowledge seemed to exert different influences on their reasoning. The results of this study show differences in how an individual thinks as well as differences between communities. Thus, science education and research considering multicultural settings are needed. In addition, science educators and researchers should pay attention to pupils' metaphysical beliefs such as their views of nature and views of science.

• Ecology and Resilient Infrastructure
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• v.9 no.3
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• pp.131-140
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• 2022

The magnitude and frequency of extreme floods are increasing owing to the effects of climate change. Therefore, multipurpose flood management techniques incorporating nature-based solutions have been introduced to mitigate the limitations of flood management and river design methods relying on existing observation data. Nature-based solutions to prepare for such extreme flooding events include ways to retreat the embankment, expand the floodplain, and reduce flood damage. To apply these technologies, adopting appropriate location selection methods based on various evaluation factors, such as flood damage reduction effects, sustainable ecological environments, river connectivity, and physical channel structure enhancements, should be prioritized. Therefore, in this study, the optimal location for implementing the multipurpose floodplain construction project was determined by selecting the location of the floodplain expansion with objectivity in the river waterfront area upstream of Daecheong Dam to downstream of Yongdam Dam. Through the final location determination, the Dongdaeje and Jeogokje sections were included in the optimal location considering both flood damage reduction and water environment improvement.

• Journal of The Korean Association For Science Education
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• v.35 no.1
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• pp.169-177
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• 2015

Since socioscientific issues (SSI) reflect various characteristics of new technologies designed to meet the incessant human needs in the contemporary society, this study explores the feasibility of adapting nature of technology (NOT) to analyze students' socioscientific decision-making. To achieve the aim, forty-five college students enrolled in a liberal arts course on science and technology studies participated in the study and responded to a GMO (golden rice) scenario in a written form. Four major viewpoints were identified from their writing: 1) is the technological artifact able to solve a societal problem?, 2) are there some alternatives to solve the societal problem?, 3) what kinds of side effects or flaws could turn up during distribution and consumption of the technological artifact?, and 4) can we cope with the technological uncertainty? We revisited the viewpoints within the NOT framework (technology as a 'fix,' cultural context and role of values, technological trade-offs, technology as a system, and technological progression). As a result, unlike NOS, NOT were quite explicitly represented in their decision-making and students' level of understanding on NOT varied. It indicates that NOT can be a promising construct for cultivating informed SSI decision-making.

• Journal of The Korean Association For Science Education
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• v.25 no.5
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• pp.610-623
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• 2005

This was a theoretical study of which the goal was to provide a foundation for developing and implementing earth science inquiry activities based on abduction as a scientific inquiry method. Through a review of relevant literature, the study examined the nature of earth science in terms of the goals of earth science inquiry and the characteristics of what is investigated in earth science. It also explored the forms and meanings of abduction, thinking strategies used in the abductive inference, and the abductive inquiry model. Abduction is the process of inferring certain rules (e.g., scientific facts, principles, laws) and providing explanatory statements or hypotheses in order to explain some phenomena. This method was found to be well-suited to the earth science inquiry which studies the causes and processes of natural phenomena in the earth and space environment. Abduction has the nature of ampliative, selective, evaluative, and creative inference, and several thinking strategies, including reconstruction of data, heuristic generalization, analogy, existential, conceptual combination, and elimination strategies, are employed for inferring rules and suggesting hypotheses. This study found the abductive inquiry model to be adaptable to earth science classrooms, and it is therefore suggested that earth science instructions should be based on the abductive method and that research work concerning the abductive inquiry in the classroom should follow.

• Journal of Korean Elementary Science Education
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• v.38 no.1
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• pp.43-54
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• 2019

In order to organize various places for science experience study, this study gathered and analyzed prior research on science experience study and various science experience perated in school. To that end, a total of 162 relevant prior studies of literature published from 2000 to 2016 were collected and 2,201 cases of science experience study conducted in 2015 were collected and analyzed. The place where the science experiential learning was done is divided into three areas of natural ecology, cultural history, facility experiential learning study, and the characteristics of participating subjects are examined. In terms of the number of articles published in the field of science-related experiential learning areas, 83 ecological experience study sites (51.2%), facilities institution experience study sites 56 (34.6%), and cultural history experience study books 23 (14.2%). Through this study, it was found out that research tendency to analyze science - related attitudes became prominent by setting study subjects using natural objects around and learning to play while playing and playing in nature. There was also an analysis by subjects of participation in science related experience learning centers. Cultural history experiential learning field was significantly lower than previous studies. In the lower grades, nature ecological experience learning was mainly performed. Combining the above findings, it can provide implications for the development of science-related experience activities. First, it is necessary to develop a technology-related experience learning center using local community resources. Second, it is necessary to expand the culture and history experience learning center related to science. Third, we need an education support center to support the expansion and operation of such a technology-related cultural history learning center.

• Journal of Korean Physical Therapy Science
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• v.13 no.4
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• pp.43-62
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• 2006

The survey was conducted with participation of the 289 handicapped persons residing at the rural area OOeup-gun in Kyungbook for the period of March 2 - May 31, 2006, to study the nature in general of the handicapped and the boundaries of their need. For the nature in general of the handicapped, the study was done by gender iscrimination, age, marital status, religion, educational level, occupation, monthly income, disability cause, disabled duration, disability type, disability level. For the boundaries of their need, the study was done by demand of financial support, educational demand, demand of voluntary workers, need of rehabilitation and medical treatment, job training, improvement of living conditions, or so. Using the Win.SPSS program, we made a frequency analysis and conclusions on the nature in general of the handicapped and the boundaries of their need on a 2-test. Conclusions are : 1. Nature in general of the handicapped The existence of the handicapped shows high at the age over 51 (71.6%), male-handicapped (65.1%), primary school graduates (62.9%), farming engaging (65.2%), monthly income less than one million Won (80.5%), cause by disease (53.8%), duration more than 10 years (61.6%), disability at level 3 (39.8%), extremity disability (66.4%). 2. Correlation of nature in general with demand of the handicapped a. In demanding the financial support, support for helper’s compensation shows high (p<0.05). In demanding the necessity of voluntary workers, the male-handicapped appears high during the absence of family assistance and the female-handicapped appears differently per week and also appears high during the absence of family assistance (p<0.05). b. In educational demand of the handicapped by their age, the age below 30 demands technical-job training and the age over 31 demands medical education for health care (p<0.01). c. In demanding the financial support by educational level, support for living cost shows high (p<0.05). d. In demanding improvement of living conditions by postnatal cause of disability, improvement of house structure shows high (p<0.05). e. In demanding assistance of voluntary workers by disabled duration, "No Need" shows high in the disabled duration more than 4 years (p<0.05). f. In demanding rehabilitation and medical treatment by disability type, home-visiting treatment, oriental medical treatment and physical therapy show high (p<0.001). g. In educational demand by disability level, medical education for health care shows high (p<0.01).

• Applied Chemistry for Engineering
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• v.23 no.1
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• pp.93-99
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• 2012

In this study, the evaluation of antioxidative activity and componential analysis of C. obtusa leaf extracts was carried out. Reactive oxygen species (ROS) scavenging activities ($OSC_{50}$) of C. obtusa leaf extracts on ROS generated in $Fe^{3+}-EDTA/H_2O_2$ system were investigated using the luminol-dependent chemiluminescence assay. The ethyl acetate fraction ($OSC_{50}$; 0.22 ${\mu}g/mL$) and aglycone fraction of C. obtusa leaf extracts (0.20 ${\mu}g/mL$) showed about 7 times more prominent ROS scavenging activity than L-ascorbic acid (1.50 ${\mu}g/mL$). The cellular protective effects of fractions obtained from C. obtusa leaf extracts on the rose-bengal sensitized photohemolysis of human erythrocytes were investigated. The ethyl acetate fraction and aglycone fraction of C. obtusa leaf extracts showed the cellular protective effects in a concentration dependent manner (5~25 ${\mu}g/mL$). The inhibitory effect ($IC_{50}$) of ethyl acetate fraction and aglycone fraction on tyrosinase exhibited 74.43 and 53.80 ${\mu}g/mL$, repectively. The aglycone fraction showed four times higher tyrosinase inhibitory effect than arbutin (226.88 ${\mu}g/mL$), known as a whitening agent. The aglycone fraction of C. obtusa leaf extracts showed three bands in TLC chromatogram and three peaks in HPLC chromatogram (360 nm). Three compounds were identified as taxifolin, quercetin and kaempferol. These results indicate that the fractions of C. obtusa leaf extracts can function as antioxidants in biological systems, particularly skin exposed to UV radiation by scavenging $^1O_2$ and other ROS, and protect cellular membranes against reactive oxygen species. The fractions of C. obtusa leaf extracts can be applicable to new functional cosmetics for antioxidan and whitening effects.

• Journal of the Korean Chemical Society
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• v.57 no.1
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• pp.115-126
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• 2013

In this study, we developed a explicit and reflective scientific inquiry learning program about nature of scientific inquiry, and compared its instructional influences with those of implicit scientific inquiry learning. We also compared students' perceptions of the program. Eighth graders at a middle school were assigned to the treatment and the control groups. The students of the treatment group participated in the program, while those of the control group participated in general scientific inquiry instruction. The analyses of the results revealed that the program was more effective in improving students' epistemological views on scientific inquiry than general scientific inquiry learning. However, there were no statistically significant differences in both test scores of science achievement and enjoyment of science lessons. The students of the treatment group perceived that group discussion on the nature of scientific inquiry was an advantage of the program. However, they still had difficulties in performing group discussion, understanding the nature of scientific inquiry, and writing and presenting their thoughts. Educational implications of these findings are discussed.