• Bulletin of the Korean Chemical Society
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• v.35 no.9
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• pp.2679-2683
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• 2014

Mechanisms underlying the impacts of interactions between carbon nanoparticles (CNPs) and ionic liquids (ILs) on the physicochemical behavior of CNPs need to be more full worked out. This manuscript describes a theoretical investigation at multiple levels on the interactions of fullerene $C_{60}$ with 21 imidazolium-based ILs of varying alkyl side chain lengths and anionic types and their impacts on $C_{60}$ dispersion behavior. Results show that ${\pi}$-cation interaction contributed to mechanism of the $C_{60}$-IL interaction more than ${\pi}$-anion interaction. The calculated interaction energy ($E_{INT}$) indicates that $C_{60}$ can form stable complex with each IL molecule. Moreover, the direction of charge transfer occurred from IL to $C_{60}$ during the $C_{60}$-IL interaction. Quantitative models were developed to evaluate the self-diffusion coefficient of $C_{60}$ ($D_{fullerene}$) in bulk ILs. Three interpretative molecular descriptors (heat of formation, $E_{INT}$, and charge) that describe the $C_{60}$-IL interactions and the alkyl side chain length were found to be determinants affecting $D_{fullerene}$.

• Journal of Environmental Health Sciences
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• v.36 no.1
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• pp.1-13
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• 2010

Evidences supporting gene-environment interaction are accumulating in terms of environmental exposure including lifestyle factors and related genetic variants. One form of defense mechanism against cancer development involves a series of genes whose role is to metabolize (activation/detoxification) and excrete potentially toxic compounds and to repair subtle mistakes in DNA. The purpose of this article is to provide a brief review of the notion of gene-environment interaction, environmental/occupational carcinogens and related cancers, and previous studies of gene-environment interaction on cancers caused by exposure to carcinogenesis. With a number of studies on the interaction between lifestyle factors (e.g., smoking and diet) and genetic polymorphisms in genes involved in xenobiotic metabolism and DNA repair excluded, only several studies have been conducted on the interactive effects between polymorphisms of CYPs, GSTs, ERCCs, XRCCs and environmental/occupational carcinogens such as vinyl chloride, benzo[a]pyrene, and chloroform on carcinogenesis or genotoxicity. Future studies may need to be conducted with sufficient number of subjects and based on occupational cohorts to provide useful information in terms of advanced risk assessment and regulation of exposure level.

• Knowledge Management Research
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• v.10 no.1
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• pp.17-32
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• 2009

Cyber University has been continuously increased since it is of great necessity of education through lifelong study. Recently, the management of cyber universities does not ensure education success, because some problems are coming out. Now we are to take an interest in qualitative level of e-learning. The purpose of this study is to classify and investigate interaction factors of e-learning, which were one of the restrictions to develop e-learning, influence learning flow and satisfaction. The authors discuss the implications of the findings for interaction and learning flow theory and practice.

• Earthquakes and Structures
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• v.6 no.2
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• pp.163-179
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• 2014

Dynamic test with scaled model of a group of intake towers was performed to study the dynamic interaction between water and towers. The test model consists of intake tower or towers, massless foundation near the towers and part of water to simulate the dynamic interaction of tower-water-foundation system. Models with a single tower and 4 towers were tested to find the different influences of the water on the tower dynamic properties, seismic responses as well as dynamic water-tower interaction. It is found that the water has little influence on the resonant frequency in the direction perpendicular to flow due to the normal force transfer role of the water in the contraction joints between towers. By the same effect of the water, maximum accelerations in the same direction on 4 towers tend to close to each other as the water level increased from low to normal level. Moreover, the acceleration responses of the single tower model are larger than the group of towers model in both directions in general. Within 30m from the surface of water, hydrodynamic pressures were quite close for a single tower and group of towers model at two water levels. For points deeper than 30m, the pressures increased about 40 to 55% for the group of towers model than the single tower model at both water levels. In respect to the pressures at different towers, two mid towers experienced higher than two side towers, the deeper, the larger the difference. And the inside hydrodynamic pressures are more dependent on ground motions than the outside.

• Journal of Engineering Education Research
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• v.18 no.1
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• pp.61-73
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• 2015

The purpose of this study is to suggest some direction to support learning of students in college of engineering. It results from the assumption that engineering education accreditation should come with assessment of the educational process. To analyze the learning process, this study analyzed 5 categories - involvement in and out of instruction, faculty-student interaction, teaching-learning outcomes, and the system of student support. The Research method was questionnaire, and T-test and hierarchical linear model were used. The major findings are as follows. Major-level of satisfaction in teaching-learning and optional-level of satisfaction in teaching-learning are good. But the degree of self-directed learning activities and student-faculty interaction is low, and writing attitude and learning outcomes are not good. Student-faculty interaction, high-order thinking activities and active involvement have a good influence on learning outcomes. So this study suggests to enhance active involvement in instruction, high-order thinking activities, writing skills, and interaction with faculty for the improvement of quality of higher education.

• Journal of Korean language education
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• v.25 no.1
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• pp.53-82
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• 2014

This study aims to find the method to promote interaction in L2 classrooms. Active interaction between learner-to-learner and learner-to-teacher in L2 classroom plays an important role in language acquisition. In light of this, L2 classroom would benefit with the help of learning tools such as Clickers which helps learners to express their level of understanding during the process of learning itself. This is because the anonymity of Clickers allows learners to express their needs without the social risks associated with speaking up in the class. It allows for an evaluative feedback loop where both learners and teachers understand the level of progress of the learners, better enabling classrooms to adapt to the learners' needs. Eventually this tool promotes participation from learners, This is in turn, believed to be effective in fostering classroom interaction, allowing learning to take place in a more comfortable yet vibrant way. This study is finalized by presenting the result of an experiment conducted to verify the effectiveness of this approach when teaching pragmatic aspect of the Korean expressions with similar semantic functions. As a result of the research, the learning achievement of learners in the experimental group was found higher than the learners' in a control group. Analyzing the data collected from a questionnaire given to the learners, the study presented data suggesting that this approach increased the scope of interactivity in the classroom, thus enhancing more active participation among learners. This active participation in turn led to a marked improvement in their communicative abilities.

• Journal of Korea Water Resources Association
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• v.41 no.9
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• pp.919-927
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• 2008

Flow exchanges between stream and groundwater are assessed on urban streams in Daegu, Korea. Two rivers and 25 streams with the total length of 240 km run through the study area. The interaction between surface water and groundwater was estimated using Darcy's method. The study was conducted by dividing the basin into 16 smaller watersheds, and for comparison purposes. Groundwater level, surface water level, hydraulic conductivity, thickness of aquifer, and the distance between the well and the nearest stream were used for quantifying the interaction. To investigations the groundwater interaction in the watersheds, the amount of effluent seepage from groundwater to the stream, the amount of influent seepage from the stream to groundwater, and the amount of annual interaction between surface water and groundwater were computed. The total amount of effluent seepage from the groundwater to stream in the basin was approximately $72{\times}10^6m^3/year$. The total amount of influent seepage from the stream to groundwater was approximately $35{\times}10^6m^3/year$. It appeared that the total amount of annual interaction between surface water and groundwater was approximately $108{\times}10^6m^3/year$ and the total groundwater flow balance was approximately $37{\times}10^6m^3/year$. The annual amount of interaction between the surface water and groundwater was the largest in the Goryung Bridge Basin($29{\times}10^6m^3/year$) and the least in the Dalchang Dam Basin($0.2{\times}10^6m^3/year$). The results show that flow exchanges between stream and groundwater are very active and that there are significant difference among the smaller watersheds. Finally, the results indicate that it is necessary to further investigate to more precisely understand the interaction characteristics between surface water and groundwater in urban areas.

• Journal of The Korean Association For Science Education
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• v.30 no.5
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• pp.533-543
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• 2010

This paper analyzed the improvement of cognitive level of the students and interactions which occurred in each step of free-topic scientific inquiry to help science teachers understand free-topic scientific inquiry better. Free-topic scientific inquiry is helpful to students with a deep strategic learning goal orientation type or a deep strategic ability goal orientation type in their transition (2B/3A) of cognitive levels. Most students have difficulties in the phase of establishing topics and hypotheses. The result says that the discussion techniques are improved through free-topic scientific inquiry, but the quality of interaction is not easily improved. The deep strategic learning goal orientation type concretizes opinion through interaction in free-topic scientific inquiry. The deep strategic ability goal orientation type are actively involve in the interaction, but they pay no attention to the process because they stick to the result. The surface strategic ability goal orientation type can not deepen a discussion due to high frequency of low level inquiry. However, the frequency of high level inquiry increases through free topic scientific inquiry operation. As a result, the characteristics of free-topic scientific inquiry were discussed and the educational implications of the progress of free-topic scientific inquiry and the organization of grouping were drawn.

• Korean Journal of Health Education and Promotion
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• v.32 no.4
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• pp.79-92
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• 2015

Objectives: The purpose of this study is to identify the trends of jjok-bang research based on the perspective of Community-Based Participatory Research and Social Ecological Model and to provide information for future public health interventions, policy designs, and policy implementations. Methods: Studies used in the systematic review are published from 1999 to 2014 and searched using key words such as 'jjok-bang' and 'single room occupancy' using domestic and international electronic databases. However, there were no studies from abroad published during this period. Search in domestic databases such as KCI, KISS, RISS generated 119 studies. In this paper, 20 cases which meet the criteria of the systematic review were included in the final analysis. Results: The contents of research included are the life of jjok-bang inhabitants(9 cases), the demand for welfare services(4 cases) and welfare need(2 cases), mental health(1 cases), and the history of jjok-bang formation(4 cases). Fourteen cases of empirical study were analyzed focusing Community-Based Participatory Research and Social Ecological Model. Some of research was carried out forming a partnership with various community partners and this trend increased since 2008. There are high frequency of intrapersonal level and interpersonal level studies. However, studies looking at the organization, community or policy level were relatively few. Conclusions: Future studies of jjok-bang area should consider the various social determinants which affect the health delivery system, community organization and policies, as well as individual or community level.

• International Journal of Human Ecology
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• v.16 no.1
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• pp.25-35
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• 2015

The primary purpose of this study was to examine to what extent adolescents' daily self-evaluation mediates the effect of experiencing intimacy in parent-adolescent interactions on positive peer interactions the next day, even after controlling for gender and grade level. We employed a daily diary method for seven days in a sample of 452 Korean adolescents, collecting checklist data at the end of each day. Data were analyzed by using hierarchical linear modeling. According to moderated multilevel mediation analyses, the variance of self-evaluation explained 83% of the variance in the lagged effect of parental intimacy on the next day peer interaction even after the upper-level effects of gender and grade level were accounted for. Forth graders were more likely than 7th graders to have a more positive view of themselves when they experienced parental intimacy the previous day. Girls were less likely to experience positive peer interactions when they perceived less intimacy with their parents the day before. Results suggested that it would be most effective for peer relationship programs to teach parents and adolescents how to experience intimacy in their daily interactions, particularly in ways that help adolescents to think more positively about themselves. It would be helpful for parents to learn about various ways to compliment and encourage the adolescent child in everyday conversations. Lastly, findings in grade level differences also suggest that these programs might be especially effective for 4th graders more than 7th graders.