• Korean Journal of Environmental Agriculture
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• v.40 no.4
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• pp.260-269
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• 2021

BACKGROUND: Diquat dibromide is a fast-acting nonselective herbicide and plant growth regulator. In this study, in order to understand the possibility of unintentional pesticide contamination in the following crops, the phytotoxicity and transition of diquat dibromide residue in soil into the following crops such as pepper, radish, lettuce and corn have been assessed through phytotoxicity trial and residual evaluation in the unintentional contamination of the higher residual diquat dibromide. METHODS AND RESULTS: The pepper, radish, lettuce and corn were cultivated in the sandy soil and loam soil where the 35 mg/kg and 90 mg/kg diquat dibromide were applied, respectively. Mild growth inhibition symptoms were observed in radish, lettuce and corn crops at the 90 mg/kg- diquat dibromide treatment on the 30 day of cultivation. Diquat dibromide was analyzed using liquid chromatography QTRAP (LC-MS/MS). The recovery rates of diquat dibromide from soil and crop were determined within range from 89.1 to 116.4% with relative standard deviation less than 14.7%. Diquat dibromide residues in soil were found to be 23.90-30.22 and 69.59-82.57 mg/kg from the 35 mg/kg and 90 mg/kg of diquat dibromide-treated soil, respectively after 30 days of crop cultivation. This result implicates that diquat dibromide did not convert to metabolites and remained mostly in the soil, even though it was partially decomposed during crop cultivation. In addition, the diquat dibromide in pepper and radish that were grown for 47 days, and lettuce and corn that were cultivated for 30 days were detected to be 0.01 mg/kg or less in the sandy loam and loam soil where the 90 mg/kg diquat dibromide was applied. CONCLUSION(S): Diquat dibromide did not cause severe phytotoxicity in the following crops as well as it did not uptake and distribute to the following crops, even though it was considered to be residual in the soil.

• Journal of Korea Entertainment Industry Association
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• v.14 no.3
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• pp.117-132
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• 2020

The purpose of this study is to examine the lifelong education policy in Korea and Germany, focusing on the historical transition process, and to explore desirable ways to develop the lifelong education policy in Korea. To this end, We compared and analyzed Korea and Germany's lifelong education policy using research papers on lifelong education and practical data published by BMBF, DIE, DVV, EAEA, UIL, and NILE. As a result of the study, German lifelong education policy has improved social and vocational professionalism running programs suitable for the characteristic of region, Korean lifelong education policy lacks civic education in terms of local lifelong education due to political sensitivity. In addition, Germany is expanding the participation rate of lifelong education by constructing an environment where it is easy to participate in lifelong education, while Korea's participation rate in lifelong education is lower than that of advanced OECD countries. At last, the German lifelong education policy pursues a natural change in the needs of the society, the ideological principle of which require education be independent. On the other hand, the study confirms that Korean lifelong education policy tends to be controlled by the central government. As a result of this study, Germany's lifelong education policy provide the following implications for Korea's lifelong education policy. First, This dissertation emphasizes the need for the learner-centered operation as the needs of educational consumers become more diverse. Secondly, It highlights the need for activation of lifelong education in career education. Third, The expansion of the lifelong education budget to support good quality lifelong learning. Fourth, Holistic and long-term system for sustainable lifelong learning society needs to be structured.

• Journal of Microbiology
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• v.43 no.3
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• pp.285-294
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• 2005

A bacterial strain M4-7 capable of degrading various polyesters, such as poly$(\varepsilon-caprolactone)$, poly(3-hydroxybutyrate-co-3-hydroxyvalerate), poly(3-hydroxyoctanoate), and poly(3-hydroxy-5-phenylvalerate), was isolated from a marine environment and identified as Pseudomonas alcaligenes. The relative molecular mass of a purified extracellular medium-chain-length poly(3-hydroxyalkanoate) (MCL-PHA) depolymerase $(PhaZ_{palM4-7})$ from P. alcaligenes M4-7 was 28.0 kDa, as determined by SDS-PAGE. The $PhaZ_{palM4-7}$ was most active in 50 mM glycine-NaOH buffer (pH 9.0) at $35^{\circ}C$. It was insensitive to dithiothreitol, sodium azide, and iodoacetamide, but susceptible to p-hydroxymercuribenzoic acid, N-bromosuccinimide, acetic anhydride, EDTA, diisopropyl fluorophosphate, phenylmethylsulfonyl fluoride, Tween 80, and Triton X-100. In this study, the genes encoding MCL-PHA depolymerase were cloned, sequenced, and characterized from a soil bacterium, P. alcaligenes LB19 (Kim et al., 2002, Biomacro-molecules 3, 291-296) as well as P. alcaligenes M4-7. The structural gene $(phaZ_{palLB19})$ of MCL-PHA depolymerase of P. alcaligenes LB19 consisted of an 837 bp open reading frame (ORF) encoding a protein of 278 amino acids with a deduced $M_r$ of 30,188 Da. However, the MCL-PHA depolymerase gene $(phaZ_{palM4-7})$ of P. alcaligenes M4-7 was composed of an 834 bp ORF encoding a protein of 277 amino acids with a deduced Mr of 30,323 Da. Amino acid sequence analyses showed that, in the two different polypeptides, a substrate-binding domain and a catalytic domain are located in the N-terminus and in the C-terminus, respectively. The $PhaZ_{palLB19}$ and the $PhaZ_{palM4-7}$ commonly share the lipase box, GISSG, in their catalytic domains, and utilize $^{111}Asn$ and $^{110}Ser$ residues, respectively, as oxyanions that play an important role in transition-state stabilization of hydrolytic reactions.

• Korean Journal of Environment and Ecology
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• v.33 no.1
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• pp.52-63
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• 2019

This study analyzed the characteristics of vegetation structure of the camphor tree (Cinnamomum japonicum) community in the area of mount Tachibana, Kasuya county, Fukuoka Prefecture designated as a special natural monument in Japan. The survey showed overwhelming dominance of canopy tree in the canopy layer (about 30 m in tree heights and 92.79 cm in average breast height diameter) but no appearance in the understory layer or the shrub layer. In the understory layer and the shrub layer, Castanopsis sieboldii, Machilus thunbergii, Neolitsea sericea, and Cinnamomum yabunikkei, which were the competing species to the canopy layer and the late-successional species in the warm temperate climate zone, were mainly distributed. Moreover, the species diversity was generally low, indicating the vegetation characteristics that was not typical of evergreen broad-leaved forests. This is presumably because camphor trees were actively planted, protected, and cultivated to produce camphor which was valuable in the past. Although this site has not been artificially managed for the past 90 years as the raw materials of camphor have not been collected, vegetation transition did not proceed, which is unique. It is probably due to the fact that camphor was overwhelmingly dominant in the canopy layer so that the inflows of species were restricted, and young tree germination did not occur due to the allelopathy effects of camphor trees.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.4
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• pp.75-90
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• 2010

The purpose of this study is to identify landscaping costs for apartment landscapes, landscape facility factors, and the transition of spatial composition for landscapes. In addition, based on the questionnaires and analysis results for workers in related fields such as landscape design companies and construction companies, this study aimed at acquiring results for the development of current apartment landscapes and directions for improvement in the future. Through the results, it aimed at providing basic data for apartment landscapes in the future. Results showed that there was approximately a 2.6 times increase for landscaping expenses of actual apartment landscapes, and a 7.0 to 11.5 times increase in the future can be expected. The cause of such increase is the continuously growing demand for a more pleasant environment. Landscape facilities factors have been diversified, and most facilities are used as multi-purpose spaces rather than serving simple facilities. Questionnaires and field investigations showed that water facilities underwent the biggest changes, and the cause for such changes were found to be the introduction of new facilities such as water facilities and environmental structures, as well as the creation of integrated functions and spaces. Spatial composition for landscapes showed that multi-purpose spaces were established, and for the apartment differentiation strategy, there were many different changes such as theming of green areas and places for exchange among residents. For changes, the most changes were in green areas, and studies also showed that there were many changes for rest areas as well. The cause for such change is judged to have been brought about by the increase of landscape space by placing parking areas underground, and investigations showed that compared to green areas composed of large grass patches, recent apartments are establishing diverse and experience-based green areas.

• Korean Journal of Human Ecology
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• v.21 no.1
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• pp.71-82
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• 2012

The purpose of this study is to examine perceptive change in attitude toward infancy and early childhood among university students' who were exposed to a human development lecture on infancy and early childhood. This study aims to investigate the significance of education in shaping attitudes related to child development and the importance of infancy and early childhood as developmental stages. This study also seeks to provide basic data for expanding and systematizing relevant educational programs. Fifteen university students who attended a lecture on human development were divided into four groups with three groups containing 4 members and one group containing 3 members. The following results were obtained: 1) Before attending the lecture on human development, students perceived infancy as a period dominated by feelings of helpless, indifference, and a general lack of knowledge or ability to interact with their environment; 2) Before attending the lecture on human development, students perceived early childhood as an initial period of transition that can potentially influence one's future; 3) After attending the lecture, students were better able to rationalize the developmental importance of infancy and early childhood. 4) After attending the lecture, students displayed broader understanding of the importance of early childhood on human development. This study also discusses the necessity for continuous and systematic provision of programs to help adults develop a positive perception of infancy and early childhood as a developmental process related to parenting skills.

• Tribology and Lubricants
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• v.30 no.2
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• pp.108-115
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• 2014

The friction behaviors of bulk amorphous thermal spray coating (BAC) and second phase-reinforced composite coatings using a high velocity oxy-fuel spraying process were investigated using a ball-on-disk test rig that slides against a ceramic ball in an atmospheric environment. The surface temperatures were measured using an infrared thermometer installed 50 mm from the contact surface. The crystallinities of the coating layers were determined using X-ray diffraction. The morphologies of the coating layers and worn surfaces were observed using a scanning electron microscope and energy-dispersive spectroscopy. The results show that the friction behavior of the monolithic amorphous coating was sensitive to the testing conditions. Under lower than normal loads, a low and stable friction coefficient of about 0.1 was observed, whereas under a higher relative load, a high and unstable friction coefficient of greater than 0.3 was obtained with an instant temperature increase. For the composite coatings, a sudden increase in friction coefficient did not occur, i.e., the transition region did not exist and during the friction test, a gradual increase occurred only after a significant delay. The BAC morphology observations indicate that viscous plastic flow was generated with low loads, but severe surface damage (i.e., tearing) occurred at high loads. For composite coatings, a relatively smooth surface was observed on the worn surface for all applied loads.

• Journal of Engineering Education Research
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• v.19 no.2
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• pp.45-52
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• 2016

The employment rate of a college has long been one of the most important elements in college survival strategies. Employment rates may not be key to colleges' survival in other countries, but they are fundamental to colleges in Korea as seen in the Korean government-led National Competency Standard (NCS), which has been underway since its introduction to colleges in Korea. Against this backdrop, if the engineering accreditation system can contribute to improving employment rate in this context, it can take root more quickly. The process conducive to improving employment rates can be classified as both direct and indirect methods. With dwindling school-age population having impacts on colleges and universities, the environment and the education directions of colleges have rapidly been shifting since the introduction of the NCS. Therefore, various survival strategies for colleges need to be developed. An indicator of employment rate of college graduates is among the most important things during this transition process. The Department of Mechanical Engineering at Koje College has consistently shown good records during the past 5 years by matching the accreditation schemes and employment strategies. The department will help put in place the engineering technology education accreditation system at the college through its various innovative and effective programs. To formulate a better employment strategy, it is needed to reflect and consolidate the engineering accreditation scheme into the existing employment policy of college. In short, this paper examines both the engineering accreditation scheme and the employment policy in ways that helps produce a coupling matrix structure. This study looks into the measures for improving employment rates by better adjusting the engineering education methods under the accreditation scheme.

• School Mathematics
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• v.15 no.3
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• pp.503-531
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• 2013

This study aims to investigate how secondary mathematics teachers use mathematics curriculum materials such as textbooks and teachers' guide in planning lessons and for their learning. 24 in-service mathematics teachers participated in surveys and two among them were interviewed. The findings from the data analysis suggest that: a) the teachers actively engaged in decision-making processes of the transition from written curriculum to intended curriculum; and b) the teachers showed a tendency of consulting to the ideas suggested in the curriculum materials for selecting objectives and contents for lessons and the what to assess, not ideas for selecting teaching methods and how to assess. Also, various factors such as students' achievement, participation, interest in mathematics, family environment, and college entrance were identified to influence the teachers' use of the curriculum materials.

• Journal of Family Resource Management and Policy Review
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• v.20 no.3
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• pp.95-113
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• 2016

This study investigates the potential for multi-cultural youths, given their innate bilingual and dual culture, to be trained as the competent ODA professionals. For the purpose of collecting information, we organized two different kinds of FGI in 2015. The first FGI was conducted with a group of 10 expert participants from August 17 to September 25. The second FGI was conducted four times, from October 5 to October 23, with 13 adolescents from multi-cultural families from Russia, Mongolia, Vietnam, India, Indonesia, Japan, and China. The semi-structured interview items were passed through a formal review process of the Institutional Ethics Committee. Furthermore, with the participants' pre-consent to recording, all recorded data were categorized through the transcription process. The results are as follows. While the potential for nourishing bilingual and dual cultural capabilities are high for the adolescent children of multi-cultural families, the expert group also emphasized the negative aspects of these capabilities being suppressed due to the relatively oppressed family environment. The expert group therefore suggests the following: building parent awareness of ODA human resources, developing an educational career transition roadmap, and providing institutional incentives for ODA. In addition, to some extent, the researchers were able to detect some positive self-esteem among the adolescent children of multi-cultural families as a result of the bilingual and dual cultural competencies required to be ODA personnel. In sum, the research provides insight into the need for national social support for the adolescent children of multi-cultural families, so that their strengths are not extinguished, in order that they might grow up as competent ODA personnel.