• Korean Journal of Microbiology
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• v.54 no.4
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• pp.428-435
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• 2018

In this study, we isolated and identified bacteria from freshwater and soil collected from Osang reservoir, to screen antimicrobial bacteria against various pathogenic bacteria. 38 strains were isolated and assigned to the class Proteobacteria (22 strains), Actinobacteria (7 strains), Bacteroidets (6 strains), and Firmicutes (3 strains) based on 16S rRNA gene sequence analysis. Among them, strain OS17 showed a good growth inhibition against 5 methicillin-resistant Staphylococcus aureus subsp. aureus strains and Bacillus cereus, Bacillus subtilis, Filobasidium neoformans. As a result of the 16S rRNA gene sequence analysis, strain OS17 show the high similarity with Burkholderia ambifaria $AMMD^T$, B. diffusa $AM747629^T$, B. tettitorii $LK023503^T$ 99.8%, 99.7%, 99.6%, respectively. We investigated cell growth and antimicrobial activity according to commercial culture medium, temperature, pH for culture optimization of strain OS17. Optimal conditions for growth and antimicrobial activity in strain OS17 were found to be: YPD medium, $35^{\circ}C$ and pH 6.5. When the strain was cultured in LB, NB, TSB, R2A media at $20^{\circ}C$ and $25^{\circ}C$, the antimicrobial activity did not show. Culture filtrate of strain OS17 showed antimicrobial activity against 5 MRSA strains, Bacillus cereus, Bacillus subtilis, and Filobasidium neoformans with inhibition zones from 2 to 8 mm. Optimal reaction time was 48 h in YPD medium, 100 rpm and 0.3 vvm in 2 L-scale fed-batch fermentation process for antimicrobial activity. Culture optimization of strain OS17 can be improved on antimicrobial activity. Therefore, the antimicrobial activity of Burkholderia sp. OS17 had potential as antibiotics for pathogens including MRSA.

• Journal of Korea Water Resources Association
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• v.52 no.1
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• pp.35-49
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• 2019

This study proposes a new method for categorizing the hydrological soil groups by considering the recent revision results of soil series. Also, the proposed method is evaluated by comparing the categorizing result with those based on existing three different methods. As an example, the proposed method is applied to Jeju Island to estimate the CN value, which is then compared with CN values estimated by applying the existing three different methods. Summaries of the results are as follow. (1) The revision result since 2007 shows that the soil texture has been changed in the 43 soil series, the drainage class in the 1 soil series, the permeability in the 15 soil series, and the impermeable layer in the 26 soil series. (2) The categorizing result of hydrological soil groups by applying the proposed method shows that the group B is the most dominant group covering up to 49.25%. On the other hand, one of the existing method of 1987 provides the group C as the most dominant group (46.43%). Method of 1995 defines the group B as the most dominant group (27.69%). The other method of 2007 distinguishes the group D (35.82%) to be the most dominant group. (3) Also, the CN value estimated by applying the proposed method to Jeju Island is found to be smaller than those based on existing three methods. This result indicates the possible overestimation of the CN value when applying the existing three methods.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.1
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• pp.20-25
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• 2021

The cement clinker, the main raw material of cement, is manufactured using limestone as the main material. Depending on the quality of limestone, the use of subsidiary materials changes, and has a great influence on the production of cement clinkers. In this study, the effect of CaO content of limestone, a cement clinker material, on Raw Mill grinding and sintering of cement clinker was investigated. The grinding time of the union materials changed in the content of limestone CaO was measured to identify the grinding properties. The raw material combination was cleaned within a range of 1,350-1,500℃. The sintering performance of cement clinker by Burnability index calculation was identified. The lower the grade of limestone, the lower the grinding quality of the raw material combination. The lower the CaO content of limestone, the greater the variation in F-CaO for sintering temperature. The lower the class of limestone, the higher B. I. value was calculated, indicating the lower cement clinker sintering. In addition, the mineral analysis results of cement clinker showed that if the F-CaO value was low due to the increase in sintering temperature, the Belite content decreased and the Alite content increased. In the case of Alite, the ratio of R-type decreased and that of M-type increased as the content of limestone CaO increased.

• KIPS Transactions on Software and Data Engineering
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• v.11 no.3
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• pp.133-140
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• 2022

We investigate the performance of deep learning-based Korean language models on a task of predicting the score range of Korean essays written by foreign students. We construct a data set containing a total of 304 essays, which include essays discussing the criteria for choosing a job ('job'), conditions of a happy life ('happ'), relationship between money and happiness ('econ'), and definition of success ('succ'). These essays were labeled according to four letter grades (A, B, C, and D), and a total of eleven essay score range prediction experiments were conducted (i.e., five for predicting the score range of 'job' essays, five for predicting the score range of 'happiness' essays, and one for predicting the score range of mixed topic essays). Three deep learning-based Korean language models, KoBERT, KcBERT, and KR-BERT, were fine-tuned using various training data. Moreover, two traditional probabilistic machine learning classifiers, naive Bayes and logistic regression, were also evaluated. Experiment results show that deep learning-based Korean language models performed better than the two traditional classifiers, with KR-BERT performing the best with 55.83% overall average prediction accuracy. A close second was KcBERT (55.77%) followed by KoBERT (54.91%). The performances of naive Bayes and logistic regression classifiers were 52.52% and 50.28% respectively. Due to the scarcity of training data and the imbalance in class distribution, the overall prediction performance was not high for all classifiers. Moreover, the classifiers' vocabulary did not explicitly capture the error features that were helpful in correctly grading the Korean essay. By overcoming these two limitations, we expect the score range prediction performance to improve.

• Journal of the Korean Society of Earth Science Education
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• v.14 no.3
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• pp.225-235
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• 2021

The purpose of this study is to obtain implications for the improvement direction of astronomical education methods and development of educational materials or software. In connection with the 5th grade 1st semester elementary science 'Solar System and Stars' unit, elementary pre-service teachers were given a reorganization task to compare the relative distances from the sun to the planets, and then this was analyzed. Pre-service teachers are 11 male and 19 female students in the second year of the music education department at the elementary school teacher training university in B city. The implications of the study results are as follows. First, the 'distance comparison activity using a roll of tissue paper' is suitable for simply comparing the distances from the sun to the planet, but it has limitations in allowing students to experience the vastness of the solar system or inducing student participation-centered classes. Second, it is necessary to develop software materials for elementary school students that can simultaneously reflect the size of the planet and the distance to the planet that can be applied indoors, and also experience the vastness of the solar system, as well as a wide learning space. Third, textbook materials for students have an important influence on the class design of pre-service teachers.

• Animal Bioscience
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• v.35 no.3
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• pp.367-376
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• 2022

Objective: The highly pathogenic avian influenza virus (HPAIV) is a threat to the poultry industry as well as the economy and remains a potential source of pandemic infection in humans. Antiviral genes are considered a potential factor for HPAIV resistance. Therefore, in this study, we investigated gene expression related to cytokine-cytokine receptor interactions by comparing resistant and susceptible Ri chicken lines for avian influenza virus infection. Methods: Ri chickens of resistant (Mx/A; BF2/B21) and susceptible (Mx/G; BF2/B13) lines were selected by genotyping the Mx dynamin like GTPase (Mx) and major histocompatibility complex class I antigen BF2 genes. These chickens were then infected with influenza A virus subtype H5N1, and their lung tissues were collected for RNA sequencing. Results: In total, 972 differentially expressed genes (DEGs) were observed between resistant and susceptible Ri chickens, according to the gene ontology and Kyoto encyclopedia of genes and genomes pathways. In particular, DEGs associated with cytokine-cytokine receptor interactions were most abundant. The expression levels of cytokines (interleukin-1β [IL-1β], IL-6, IL-8, and IL-18), chemokines (C-C Motif chemokine ligand 4 [CCL4] and CCL17), interferons (IFN-γ), and IFN-stimulated genes (Mx1, CCL19, 2'-5'-oligoadenylate synthase-like, and protein kinase R) were higher in H5N1-resistant chickens than in H5N1-susceptible chickens. Conclusion: Resistant chickens show stronger immune responses and antiviral activity (cytokines, chemokines, and IFN-stimulated genes) than those of susceptible chickens against HPAIV infection.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.7
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• pp.69-78
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• 2017

This study researches and analyses the state of the learning achievement assessment of the basic curriculum of the special education in the viewpoint of the individualized education pursuing for the learning and growing of each person, and discusses the political plan for support on the basis of the results. The object of study was 129 special school teachers working in B metropolitan city applying for the basic curriculum. For the measurement, the tool developed by the examination of FGI and the specialist on the basis of test research related to the evaluation tools of the learning achievement assessment for the special education was used. As the result of analysing the real state, to evaluate the individual learning and growing in the aspect of the plan, criteria, period of the evaluation, the special education teachers were approaching in detailed and precise quality, and guiding and using the evaluation results in the various ways in the prospective of the curriculum. The recognition on the sub-element in the each area of the measurement tools showed the difference by gender, age, career, academic achievement, school class, foundation type. On the basis of the results of the real state, as the political support plan, some advice were proposed, which were the expansion of the autonomy of making the curriculum achievement standard and the evaluation system, improving the field and system of the learning achievement assessment, establishing the support system to strengthen the evaluation competences in accord with the teachers' background variables, etc.

• The Journal of the Convergence on Culture Technology
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• v.9 no.4
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• pp.245-252
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• 2023

The purpose of this study was to investigate the effect of academic engagement, academic self-efficacy of problem solving ability in nursing students. Data were collected from 219 nursing students in B city and analyzed by descriptive statistics, t-test, ANOVA, Pearson correlation coefficient, and multiple regression using SPSS/WIN 22.0. The degree of problem solving ability in nursing students was 4.00±0.51. There were significant differences in problem solving ability with major satisfaction(F=9.476, p<.001), class satisfaction (F=3.079, p<.001). There was positive correlation between problem solving ability and academic engagement (r=.560, p<.001), academic self-efficacy(r=.634, p<.001). There was positive correlation between academic engagement and academic self-efficacy(r=.769, p<.001). The factors affecting problem solving ability of the study subjects were academic engagement(β=.177, p=.031), academic self-efficacy(β=.498, p<.001), with an explanatory power of 41.0%. Therefore to increase aacademic engagement and academic self-efficacy of nursing students, it is necessary to develop the program for improving the problem solving ability of nursing students.

• The Journal of the Convergence on Culture Technology
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• v.9 no.3
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• pp.271-279
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• 2023

The purpose of this study was to investigate the effect of learning flow, problem solving ability, professor-student interaction of academic achievement in nursing students. Data were collected from 274 nursing students in B city and analyzed by t-test, ANOVA, Pearson correlation coefficient, and hierarchial multiple regression using SPSS/WIN 22.0. The degree of academic achievement in nursing students was 3.70±0.70. There were significant differences in academic achievement with grade(F=4.755, p=.003), campus life satisfaction(F=5.643, p=.004), major satisfaction(t=5.794, p=.003), adapting to COVID-19(F=7.961, p<.001), satisfaction to non-face-to-face environment class(F=18.353, p<.001). There was positive correlation between academic achievement and learning flow(r=.649, p<.001), problem solving ability(r=.333, p<.001), professor-student interaction(r=.479, p<.001). The factors affecting academic achievement of the study subjects were learning flow(β=.563, p<.001), professor-student interaction(β=.280, p<.001), with an explanatory power of 52.0%. Therefore, strategies increase the academic achievement of nursing students in untact lecture, and environment improvement to increase learning flow and professor-student interaction are needed.

• The Journal of the Convergence on Culture Technology
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• v.9 no.6
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• pp.627-636
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• 2023

This study was conducted to lay the basis of the need of the self-directed learning ability, critical thinking, communicative ability, problem solving skills for nursing students by confirming the effect of problem based learning classes of nursing students. The data collection period was from March 1 to June 7, 2022. It was provided problem based learning classes to 165 nursing students located at B city. Problem based learning classes were conducted at total of 14 times, and 100 minutes/time. The collected data were analyzed using the frequency and percentage, Cronbach's α, mean and standard deviation with the SPSS Win 21.0 program, and the effectiveness verification of problem based learning classes was analyzed with a paired t-test. As a result of the effectiveness of the problem based learning class, the self-directed learning ability(t=-2.08, p=.039), critical thinking(t=-2.49, p=.014), communicative ability(t=-4.90, p<.001), problem solving skills(t=-4.84, p<.001) of nursing students who took 14 weeks of problem based learning was enhanced. Based on the results of this study, by applying it in various ways to first-year nursing students, it will be possible to use them to improve their competence, major satisfaction, and adapt to college life.