• Journal of the Korean earth science society
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• v.32 no.4
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• pp.422-434
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• 2011

The purpose of this research is to investigate the actual conditions of primary school science teaching and ways to improve it. In elementary science teaching, teachers themselves tend to have science misconceptions and insufficient science content knowledge. Experienced teachers argued that it could be hard for elementary teachers with lack of science content knowledge to provide their students with meaningful learning experiences of science. Based on the general characteristics of elementary teaching and the awareness of elementary teachers' insufficient science content knowledge, we explored the real situation of the elementary science classroom. We conducted open-ended interviews with teachers and focus group discussions on a regular basis to analyze and compare classes of five primary school teachers. Data analysis focused on why elementary students avoid science classes in upper grades of elementary school and why elementary science classes always need hands-on activities. We also discussed ways to turn hands-on investigation into minds-on investigation by connecting it to important ideas in science. Based on the results, we suggested ways to improve inservice teacher training such as designing supplementary in-service training focused on content knowledge for primary school teachers, setting up professional exchange or collaboration between primary and secondary teachers, and introducing subject-specialized teachers for the fifth and sixth graders of primary school. In particular, considering elementary teachers' insufficient science content knowledge, employing science subject matter specialists in the elementary school could be a useful strategy.

• Korean journal of applied entomology
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• v.48 no.1
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• pp.87-94
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• 2009

KNI3126 which is the eco-friendly material made by plant extracts - neem and matrine - have been evaluated for efficacies against 6 main pests and toxicity on natural enemies. Insecticidal efficacies of KNI3126 against plant hopper were above 95% at 5 days after treatment (DAT), whereas pesticidal effects against the cotton aphid were above 95% at 3 DAT and slightly decreased at 5 DAT. Insecticidal efficacy against the palm thrips resulted in lower control value as 68.1% than that of chemical insecticides. KNI3126 showed more than 95% control value against diamond back moth, suggesting that it could suppress the population of pest hard to control as eco-friendly material. Mortalities against two-spotted spider mite were about 80% at 1 DAT and over 90% at 5 DAT, respectively. For evaluation of the toxicity on natural enemies, effect against predatory natural enemy was classified as moderate selective toxicity based on the criterion of International Organization of Bio-Control (IOBC), whereas against parasitic natural enemies was found to be relatively safe. Repellent effect was weak against plant hopper, but strong against two-spotted spider mite. In the toxicity test for safety, KNI3126 was classified as the lowest level at acute oral, acute dermal and fish toxicity test and did not induce the irritancy at skin irritation test and eye irritation test.

• Journal of dental hygiene science
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• v.15 no.1
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• pp.38-45
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• 2015

This research was attempted in order to investigate the correlation of the conflict level and job satisfaction of the dental hygienists in the dental clinic agency. The subjects were 249 dental hygienists working with more than five dental hygienists at dental clinics in Daegu, eight dental clinics were randomly chosen, the researcher visited them personally and the data was obtained by self-administrated questionnaires from March 2 to March 31, 2011. In conclusion, the higher ages, monthly income and total career were, the higher levels of conflict were, and job satisfaction was significantly high when monthly income and total career were higher. Correlation between level of conflict and job satisfaction showed as level of conflict are lower, job satisfaction was significantly high. Regression analysis of the factors affecting job satisfaction, it was significantly high as monthly income was higher, friction of view and ignorance was lower. Therefore, the conflict level is reduced, the job satisfaction degree of the dental hygienist is enhanced, the dental hygienist duty efficiency is enhanced and dental service of the good quality is provided.

• Journal of the Korea Institute of Building Construction
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• v.20 no.5
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• pp.449-457
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• 2020

Due to the improvement of living standards and avoidance of the 3D industry, it is difficult to find young and competent domestic workers at construction sites, and most foreign workers are contributing to the replacement, but the quality is still deteriorating due to lack of skilled workers and aging. Precast method is a method that make members in factory and assembles them on site, which can be expected to improve labor force and quality. This study is intended to provide basic data for the development of hang-type PC beams that can be applied to the determination of the field application of developed PC beams. The U-type connecting material is installed on both ends of the hang-up PC beam, and the role of the U-type connecting material is very important because it is a simple construction method through the U-type connecting material. In addition, the performance of the U-type connecting material will determine the performance of the hang-type PC beam as the final destruction occurs in the hang-type PC beam. The material properties of U-type connecting material were identified through structural experiments, and the end test corresponding to the partial experiment was conducted based on the material test results identified. Finally, the final design value of PC beams was proposed through structural experiments for application to the site.

• Economic Analysis
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• v.25 no.1
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• pp.66-122
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• 2019

As the Korean economy grew, employment expanded steadily, with the number of economically active people increasing and the employment-to-population rate also increasing. However, the working age population started to decline in 2017, and the employment of women and young people has been sluggish. The proportion of non-salaried workers in Korea is much higher than in other OECD countries, and is also excessive, considering Korea's income levels. In addition, the proportion of non-regular workers and the proportion of workers employed at small companies are particularly high among salaried workers. In light of these characteristics of Korean employment, the urgent problems facing the employment structure can be summarized by the deepening dual structure of the labor market, the increase in youth unemployment, sluggish female employment figures, and an excessive share of self-employment. Overall, it is seen that labor market duality is the main structural factor of the employment problems in Korea. Therefore, in order to fundamentally address this employment problem, it is necessary to concentrate policy efforts on alleviating labor market duality.

• Journal of the Korean Applied Science and Technology
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• v.34 no.2
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• pp.357-366
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• 2017

Natural pigments are materials that express color and have been used in foods, cosmetics, medicine and so on. Since natural pigments are extracted from animals and plants, they are not uniform in size. Red pigments in particular are more lipophilic than other color pigments and tend to aggregate easily in aqueous solutions which make it difficult to reproduce the specific color due to size change. Found to be an allergen and the growing aversion for it to be used in foods, cochineal pigment, an animal pigment used for red pigments is being used less. In this study, red vegetable pigment lycopene extract and gardenia yellow was made uniform in size by ball-milling, then asymmetrical flow-field flow fractionation (AsFlFFF) and dynamic light scattering (DLS) were used to measure the size, and a color meter was used to confirm the color. Experimental results showed that the pigment particles were large in size and size distribution was wide before milling, but the size of the particles decreased and size distribution narrowed after milling. Color meter measurements showed that as the milling time increased, the size of the pigment particles decreased and the brightness, redness, and yellowness increased indicating a bright red color.

• Korean Journal of Environment and Ecology
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• v.22 no.5
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• pp.505-513
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• 2008

The purpose of this study is to analyze the distribution patterns and characteristics of plant species by human impact in urban areas. In order to achieve a comprehensive data acquisition of all autogenously introduced vascular plant species occurring in the city of Cheon-ju, this study made an analysis of 106 sample plots, each with a size of one hectare, These sample plots were selected to represent the typical land-use patterns within the city of Cheon-ju and to cover the various distances from the city center. Species richness, patterns of life forms, and the percentage of non-native species were analyzed in relation to the degree of hemeroby of the sample plots. It was found that the species number appeared the largest in sites that were moderately influenced. This result corresponds to the intermediate disturbance hypothesis that moderate disturbance leads to an increase in species richness. The flora of sites which were subject to the highest level of human impact, was characterized by a high proportion of annual species and non-native species. In addition, some species were divided into three groups with similar distribution corresponding to land-use type and urban zone: urbanophobic (e.g. Indigofera kirilowii, Prunus sargentii, Rhus trichocarpa), urbanoneutral (e.g. Commelina communis, Erigeron annuus, Metaplexis japonica) and urbanophilus (e.g. Euphorbia supina, Senecio vulgaris, Taraxacum officinale).

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.334-339
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• 2008

Construction that over 70% of the structure consists of concrete gets bigger and higher gradually and the demand of that is increasing as well. However, it's not easy to supply young and skilled persons on construction site because of social avoidance phenomena about 3D occupation, so it causes serious problems like aging and shortage of technicians. To solve the problems, executives related to the construction field make a management effort in various ways such as construction period shortening, labor productivity improvement and good quality but recently, they have an increasing interest in the necessity of the modularization of the high-rise building and the automation of the engineering development for the strengthening of international competitive power as more active and long-term alternatives. Therefore, this study is to propose the roadmap in order to make lots of efforts in developing construction technologies of high-rise buildings by performing a foundation study, the strategy for 4-step research development, on modularized construction system of concrete structure of high-rise buildings through domestic and foreign preceding research analyses associated with optimal design modularization technique, module factory automation and assembly automation of modularized objects.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.1
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• pp.72-81
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• 2017

There is a common misbelief that female gamers prefers simple cute easy games so that they are incompetent if higher skill level is required or disqualified to be a winning party member in MMORPG. This pink game theories are the results of video game analysis done in US and Europe way before online games and mobile games become popular thus. there are many evidences that such misconceptions do not hold anymore. However, researches on gender game culture and gender preferences have not been seriously conducted since 2007 in Korea. Thus, in this paper, we surveyed 88 male and 151 female gamers from their late teens to 30s and found a gap between behavior and perception due to serious gender stereotypes. Gender differences are still found in several areas, but the degree of differences were weakened or in different direction from 2007. The game design to attract female gamers should understand such gender gaming culture and gender difference.

• Journal of Environmental Policy
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• v.9 no.4
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• pp.125-154
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• 2010

Among the various contemporary issues that confront the nation or society, surely one of the most difficult to resolve are environmental disputes between government authorities, developers, local residents and advocacy groups. While such disputes can in some cases be the result of a selfish and illegal NIMBY("Not In My Back Yard") syndrome, they can also be an expression of rational and appropriate demands from local residents to preserve the ecology and quality of life for their communities, particularly with respect to the planning of "locally unwanted land uses(LULUs). Accordingly, rethinking NIMBYism entails several implications for planning of LULUs. Until the 20th century many planners considered only "functional rationality" in their decision making, in a confrontational "us versus them"process of "decide-announce-defend(DAD)". I believe, however, that a fair, voluntary, and negotiated process of alternative dispute resolution(ADR) based on consensus building is the means to resolving these disputes. A voluntary process is more desirable and feasible than a coercive one, making ADR well worth pursuing. From this perspective, I explore several factors which affect the resolution of environmental disputes. I suggest three main factors as follows: i) extension of citizen participation, ii) enhancement of equity, and iii) building of trust. Alternatives are presented based on these factors.