• Journal of The Korean Association For Science Education
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• v.40 no.2
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• pp.191-201
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• 2020

This study investigated verbal and physical interactions which appeared in collaborative science concept learning using augmented reality. Twelve 10th grade students participated in this study. After being organized into three four-member small groups, they participated in classes using smart device-based augmented reality application developed for the understanding of the chemical bonding concept. Their class activities were audio- and video-taped. Semi-structured interviews were also conducted. The results revealed that within individual statement units of verbal interaction, the proportions of information question/explanation and direction question/explanation were found to be high. Within interaction units, the proportions of reformative and cumulative interaction were relatively high. The proportions of progress were also found to be high within both individual statement units and interaction units of verbal interaction. Students' physical interactions were mainly conducted without meaningful verbal interactions. When their physical interactions were accompanied by knowledge construction-related verbal interactions, the proportions of gazing virtual objects and worksheet-related interactions were high. In contrast, various exploratory activities related to the manipulation of markers mainly appeared when they conducted physical interactions only, or when their physical interactions were accompanied by management-related verbal interactions. On the bases of the results, effective methods for collaborative concept learning using augmented reality in science education are discussed.

• Journal of Life Science
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• v.24 no.5
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• pp.532-542
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• 2014

This study describe seasonal patterns in the variation of phytoplankton frequency in the water surface and basal layers and their spatial distributions at seven stations in Hwadang-ri, Goseng-gun in 2013. The phytoplankton community at Hwadang-ri was very diverse, with 60 taxa identified, representing three classes. Diatoms (Bacillariophyceae) exhibited the greatest diversity, with 41 taxa identified. These were followed by the dinoflagellates Dinophyceae, Cryptophyceae, and Eugenophyceae, with 16 taxa, two taxa, and one taxon, respectively. Water surfaces were shown with the relative individual density or abundance across areas. Except in January, Shannon-Weaver indices of diversity of the water surface layer were lower than those of the basal layer. In addition, evenness indices of the basal layer were higher than those of the water surface layer, except in January. For the community as a whole, the values of ${\beta}$-diversity were low for the seven stations: 1.125 for the water surface layer and 1.481 for the basal layer. Seasonal values for ${\beta}$-diversity were similar at the seven stations: 1.725 for the water surface layer and 1.347 for the basal layer. The phytoplankton community showed high taxonomic homogeneity in all four seasons, in addition to similar trends in seasonal development at depths in the same stations. However, the size distribution of the abundance and biomass showed a statistically significant west-east difference.

• Toxicological Research
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• v.24 no.1
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• pp.37-44
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• 2008

The in vitro cell transformation assays (CTA) were performed using BALB/3T3 murine fibroblasts and HaCaT human keratinocytes in order to evaluate concordance between both in vitro CTAs and carcinogenicity with compounds differing in their genotoxic and carcinogenic potential. Six test articles were evaluated, two each from three classes of compounds: genotoxic carcinogens (2-amino-5-nitrophenol and 4-nitroquinoline-N-oxide), genotoxic noncarcinogens (8-hydroxyquinoline and benzyl alcohol), and nongenotoxic carcinogens (methyl carbamate and N-nitrosodiphenylamine). Any foci of size $\geq$2 mm regardless of invasiveness and piling was scored as positive in CTA with BALB/3T3. As expected, four carcinogens regardless of their genotoxicity had positive outcomes in two-stage CTA using BALB/3T3 cells. However, of the two genotoxic noncarcinogens, benzyl alcohol was positive CTA finding. We concluded that, of the 6 chemicals tested, the sensitivity for BALB/3T3 system was reasonably high, being 100%. The respective specificity for BALB/3T3 assay was 50%. We also investigated the correlation between results of BALB/3T3 assay and results from HaCaT assay in order to develop a reliable human cell transformation assay. However, evaluation of staining at later time points beyond the confluency stage did not yield further assessable data because most of HaCaT cells were detached after $2{\sim}3$ days of confluency. Thus, after test article treatment, HaCaT cells were split before massive cell death began. In this modified protocol for this HaCaT system, growing attached colonies were counted instead of transformed foci 3 weeks since last subculture. Compared to BALB/3T3 assay, HaCaT assay showed moderate low sensitivity and high specificity. Despite these differences in specificity and sensitivity, both cell systems did exhibit same good concordance between in vitro CTA and rodent carcinogenicity findings (overall 83% concordant results). At present the major weakness of these in vitro CTA is lack of validation for regulatory acceptance and use. Thus, more controlled studies will be needed in order to be better able to assess and quantitatively estimate in vitro CTA data.

• Korean Journal of Environment and Ecology
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• v.24 no.5
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• pp.556-565
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• 2010

Community analysis based on functional feeding groups of benthic macro invertebrates at Wangpi-cheon was assessed with the result of four field survey from October, 2007 to May, 2008. A total 138 species of benthic macro invertebrates in 58 families, 16 orders, 6 classes, and 4 phyla were collected during the field surveys. The result of EPT index value showed high value of 61.59% and it means that the stream ecosystem of Wangpi-cheon is very clear and healthy. In this study the functional feeding groups in Wangpi-cheon were divided into two groups. First, Scrapers and Collectors-Gathering group which is normally dominant in midstream showed higher dominance in main stream than tributary. Second, shredders group showed higher dominance in tributary than main stream like as the general characteristics of upriver. With the result of cluster analysis based on the similarity index, the study areas could be grouped into a natural area(A group) and an artificial disturbance area(B group; site 8 and 11) where embankment, bank and levee had been built near by. And also, the natural area(A group) was classified into two groups which had the characteristic of main(site 1, 2, 3, 4 and 7) stream and tributary(site 5, 6, 9 and 10) respectively.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2003.10a
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• pp.66-72
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• 2003

Toxicogenomics is now emerging as one of the most important genomics application because the toxicity test based on gene expression profiles is expected more precise and efficient than current histopathological approach in pre-clinical phase. One of the challenging points in Toxicogenomics is the construction of intelligent database management system which can deal with very heterogeneous and complex data from many different experimental and information sources. Here we present a new Toxicogenomics database developed as a part of 'Toxicogenomics for Efficient Safety Test (TEST) project'. The TEST database is especially focused on the connectivity of heterogeneous data and intelligent query system which enables users to get inspiration from the complex data sets. The database deals with four kinds of information; compound information, histopathological information, gene expression information, and annotation information. Currently, TEST database has Toxicogenomics information fer 12 molecules with 4 efficacy classes; anti cancer, antibiotic, hypotension, and gastric ulcer. Users can easily access all kinds of detailed information about there compounds and simultaneously, users can also check the confidence of retrieved information by browsing the quality of experimental data and toxicity grade of gene generated from our toxicology annotation system. Intelligent query system is designed for multiple comparisons of experimental data because the comparison of experimental data according to histopathological toxicity, compounds, efficacy, and individual variation is crucial to find common genetic characteristics .Our presented system can be a good information source for the study of toxicology mechanism in the genome-wide level and also can be utilized fur the design of toxicity test chip.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.2
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• pp.200-206
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• 1996

Experiment was conducted to get the information about physico-chemical properties of flue-cured tobacco on the degree of maturity cultivated in paddy-upland rotated field, and compared to upland ones. For the samples of this experiment, 3~4 leaves at each stalk position were harvested from the bottom of plants. Physico-chemical properties of cured leaves were determined from the samples collected at weekly intervals, and of obtained from 4 stalk positions. For the degree of maturity, harvested leaves were separated with visual characters into four classes such as immature, mature, ripe, and mellow. Regardless of stalk position, the order of shrinkage rate with length and width of leaves was mellow> immature> ripe> mature, and ripe leaves from paddy field showed higher shrinkage rate than those of upland. Nicotine and total nitrogen contents were decreased with the degree of maturity while reducing sugar content were showed a reverse tendency. Ripe leaves from paddy field had lower reducing sugar contents, comparing with upland tobacco. Filling capacity of cured leaves from paddy field was decreased with degree of maturity, but there was no difference between upland and paddy tobacco. Shatter index was increased in the oeder of immature > mellow > mature > ripe. Chemical components of cigarette smoke from paddy field tobacco were little higher in $CO_2$ total particulate matter and tar contents, while combustibility was little lower than that of upland tobacco. It was also evaluated that paddy field tobacco was unfavorable for the non-volatile organic and higher fatty acids contents comparing with upland tobacco.

• The Journal of the Korea Contents Association
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• v.17 no.7
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• pp.113-123
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• 2017

This research is designed to review the systems thinking and STEAM theory while ascertaining the effects of the classroom application of the STEAM programs based on systems thinking appropriate for studying climate change. The systems thinking based STEAM program has been developed by researchers and experts, who had participated in expert meetings in a continued manner. The program was applied to science classes over the course of eight weeks. Therefore, the application effects of the systems thinking based STEAM program were analyzed in students' systems thinking, STEAM semantics survey, and students' academic achievement. The findings are as follows. First, the test group has shown a statistically meaningful difference in the systems thinking analysis compared to the control group in the four subcategories of 'Systems Analysis', 'Personal Mastery', 'Shared Vision' and 'Team Learning' except for 'Mental Model'. Second, in the pre- and post-knowledge tests, the independent sample t-test results in the areas of science, technology, engineering, art and mathematics show statistically meaningful differences compared to the control group. Third, in the academic performance test regarding climate change, the test group displayed higher achievement than the control group. In conclusion, the system-based STEAM program is considered appropriate to enhance amalgamative thinking skills based on systems thinking. In addition, the program is expected to improve creative thinking and problem-solving abilities by offering new ideas based on climate change science.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.1
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• pp.121-133
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• 2016

It was required to evaluate ecological restorations in a comprehensive way in order to systematically manage conservation areas such as DMZ and national parks in South Korea. In this research we developed a new approach to evaluating ecological restorations with more various indexes than vegetation covering-related indexes. By analyzing damaged areas in the vicinity of DMZ, major damaged types were identified as six classes: landform modification, surface loss, soil pollution, soil physio-chemical modification, vegetation decline and vegetation damaged. From literature review, 39 indexes were selected and were grouped into four divisions: soil property, vegetation growth & structure, habitat property and landscape structure & functions. By conducting a survey with the selected indexes targeting relevant experts, data on relative importance among the divisions and indexes by damaged type were collected. As a result, it was found that the orders and values of weighted values of the divisions were different by damaged type: for example, soil property (0.402), vegetation growth & structure (0.209), habitat property (0.225), landscape structure & function (0.163) for "landform modification"; but soil property (0.171), vegetation growth & structure (0.401), habitat property (0.270), landscape structure & function (0.158) for "vegetation decline". Similarly, evaluation indexes showed different orders and values of relative importance, easiness in field measurement and representativeness for the division by damaged type, and the values were used for calculating importance factor for each index. In the evaluation table, score1 and score2 were made by the importance factors of indexes multiplied by distribution values which present grades and by the weighted values of divisions. In conclusion, while dealing with the damaged type was considered significant for evaluating and managing restorations, further tests on this table with a range of cases were needed to improve its quality.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.296-302
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• 2018

The purpose of this study is to assess the play and leisure status of children in Korea. The subjects of the study were 564 children in elementary, middle, and high school classes in four districts of Seoul and one rural district in Gyeonggi Province. We surveyed and analyzed the objects, time, place and cost of both play and leisure and investigated the differences according to age, region and sex. The results of this study can be summarized as follows. First, the children's play and leisure subjects were more likely to be friends than family members, and the proportion of fathers among the parents decreased with increasing age. Second, the children spent most of their play and leisure time on media related activities. Third, unlike in the past, the children's places of play and leisure were very diverse and included many adult or commercial places, such as cafes and karaoke studios. Fourth, there were no differences in the cost of play and leisure, depending on the age or sex of the children, but there were regional differences.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.5
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• pp.139-150
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• 2007

As computer technology has been rapidly advanced, geographic information system (GIS) is recently used in many disciplines. In this study, for a model area in Seoul, seismic hazard potential relating to site effects, which are influenced by the subsurface geotechnical conditions, was estimated using the GIS tool. The distribution of pre-existing borehole drilling data in Seoul metropolitan area was examined for the regional estimation of site-specific seismic responses at the model area. Spatial geo-layers across the entire model area were predicted by constructing a GIS-based geotechnical information system (GTIS). A microzonation of site period $(T_G)$ for estimating site-specific seismic responses at the model area was performed within the GTIS. The spatial microzoning map of $T_G$ indicated seismic vulnerability of two- to four-storied buildings in the model area. Furthermore, a site classification map for determining the design ground motion was established based on the $T_G$ within the GTIS. This informed that most of location in the model area was categorized into current site classes C and D. This seismic microzonation framework for the model area could be applicable particularly in the entire Seoul metropolitan area based on the pre-existing borehole data.