• Journal of Power Electronics
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• v.13 no.5
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• pp.877-883
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• 2013

This paper discussed a transformer-less shunt static synchronous compensator (STATCOM) with consideration of the following aspects: fast compensation of the reactive power, harmonic cancelation and reducing the unbalancing of the 3-phase source side currents. The STATCOM control algorithm is based on the theory of instantaneous reactive power (P-Q theory). A self charging technique is proposed to regulate the dc capacitor voltage at a desired level with the use of a PI controller. In order to regulate the DC link voltage, an off-line Genetic Algorithm (GA) is used to tune the coefficients of the PI controller. This algorithm arranged these coefficients while considering the importance of three factors in the DC link voltage response: overshoot, settling time and rising time. For this investigation, the entire system including the STATCOM, network, harmonics and unbalancing load are simulated in MATLAB/SIMULINK. After that, a 35KVA STATCOM laboratory setup test including two parallel converter modules is designed and the control algorithm is executed on a TMS320F2812 controller platform.

• Journal of Convergence for Information Technology
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• v.11 no.2
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• pp.138-145
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• 2021

The purpose of this study was to investigate the mediating effects of academic procrastination behavior on the relationship between academic stress and dropout intention. The research questions are First, does the academic stress of college students influence the intention to drop out? Second, does academic procrastination behavior the relationship between academic stress and dropout intention? A survey was conducted on 218 college students about academic stress, dropout intention, and academic procrastination behavior. Correlation analysis was conducted to find out the relationship between academic stress, dropout, and academic procrastination behavior, and Multiple regression analysis was performed to determine the moderating effect of academic procrastination behavior. The mediating effect was verified using Baron and Kenny's procedure, and the significance was verified by Sobel verification. The results are as follows: First, academic stress, dropout intention, and academic delay behavior showed significant positive correlations.. Second, Academic stress showed 15% of explanatory power as an influential factor on dropout intention, and 5% of explanatory power was an influential factor on academic procrastination behavior. Third, the through mediation analysis, there was partial mediated effects of academic procrastination behavior between academic stress and dropout intention. Our findings suggest that to improve the dropout intention among college students, educators should carefully design and develop an education program

• Journal of Integrative Natural Science
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• v.8 no.1
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• pp.56-59
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• 2015

To explore effects on each friendship, family, romance, and community in sub-variables of loneliness on academic achievement in science for Y-middle school students, multiple regression analysis is carried out by stepwise method. As the results, I found the following facts. Academic achievement in science for the students was expressed by the following equation. Academic Achievement=48.765+4.012${\times}$[Family](t=2.082, p=.039)-3.957${\times}$[Romance](t=-3.147, p=.002)+5.281${\times}$[Community](t=2.965, p=.003). And each variable value of the explanatory power affecting academic achievement in science for the students is presented in order of community (12.0%), family (6.6%), and romance (6.3%). But the friendship variable is not significant in affecting academic achievement in science.

• The Journal of Korean society of community based occupational therapy
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• v.1 no.1
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• pp.49-57
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• 2011

This study investigated the relationship between learning strategies and achievements of the students in the department of health science, and differences between higher academic achievers and lower academic achievers in the use of the learning strategies. The results were as follows. First, there was a correlation between academic achievements and self-efficacy and power of execution in the personality area. Second, there was a positive correlation between academic achievements and academic motivation, a negative correlation between academic achievements and avoidnat motivation, in the motivation area. Third. there was a correlation between academic achievements and all 8 factors in the behavior area. In the use of learning strategies, there was a difference found in self-efficacy and the power of execution between the higher academic achievers and the lower academic achievers. It also was found that the lower academic achievers perceived more depression, showed remarkably lower motivation and higher avoidance motivation, than the higher academic achievers. Lastly, the lower academic achievers was lagged behind noticeably compared to the higher academic achievers in the ability of using all factors of the behavior area.

• The Journal of Korean Academic Society of Nursing Education
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• v.15 no.1
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• pp.120-127
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• 2009

Purpose: In the literature power analysis in experimental studies is often executed and reported falsely. This descriptive study was done to promote the correct application of the Cohen(1988)'s power analysis method. Method: Articles of experimental studies from a nursing journal were selected and reviewed to examine the uses of and the reports on the power analysis process. Also, the appropriate power analysis process was discussed with an example of the most common experimental design, an independent two-group design with t test analysis plan. Result: Around half the experimental studies examined reported that they carried out power analysis. Cohen's method was the most frequently utilized but with accuracy in question. Conclusion: Power analysis to estimate sample size is the interplay between alpha, power, and effect size, and other factors in the case of t test analysis. Researchers should have a clear understanding of how to apply the Cohen's power analysis method so they do not produce poorly estimated sample sizes.

• The Journal of the Convergence on Culture Technology
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• v.10 no.3
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• pp.503-512
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• 2024

This study examines the essays of academic background, written by students from a university, which is classified into prestigious universities in Korean society. By Latent Dirichlet Allocation, 172 essays were analyzed to explore the students' perspectives of the academic fractionalism. The analysis identified five topics such as, functional aspects (Topic 1), double-edged nature (Topic 2), power communities (Topic 3), symbols of victory (Topic 4), and dysfunctional aspects (Topic 5). The most frequently appearing keywords are 'individual,' 'status,' and 'means' in Topic 1, 'definition,' 'school,' and 'meaning' in Topic 2, 'people,' 'origin,' and 'power' in Topic 3, 'university,' 'ability,' and 'effort' in Topic 4, and 'academic achievement,' 'South Korea,' and 'origin' in Topic 5. By exploring the topics, we found that students regarded class reproduction by education as important social issues and they showed little interest in other factors influencing academic fractionalism, such as race or ethnicity. these findings suggest that professars, who teach the impact of education on academic fractionalism, deal with the influence of diverse factors on academic fractionalism.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.6_2
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• pp.1033-1046
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• 2023

The purpose of this study was to investigate the relationship between personality, positive psychological capital, and academic resilience of nursing students and to identify the factors affecting academic resilience of nursing students. Data were collected from 199 nursing students in their first and second year at C nursing college in M-gun, J-do, and a survey was conducted from July 10 to July 28, 2023. The collected data were analyzed using descriptive statistics, t-test, one-way ANOVA, Scheffe test, Pearsons correlation coefficient, Stepwise multiple regression analysis was conducted. Personality had a significant positive correlation with positive psychological capital(r=.62, p<.001) and academic resilience(r=.68, p<.001), and positive psychological capital had a significant positive correlation with academic resilience(r=.79, p<.001). The major factor influencing the academic resilience of nursing students was positive psychological capital, followed by personality, interpersonal relationship, and college life satisfaction, and their total explanatory power was 72% (F=102.85, p<.001). Based on the results of this study, it is necessary to develop an educational program that can increase positive psychological capital in order to strengthen the academic resilience of nursing students, and efforts should be made to introduce and manage it in the nursing curriculum.

• The Journal of the Convergence on Culture Technology
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• v.8 no.4
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• pp.99-106
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• 2022

The purpose of this study was to investigate the effect of academic stress, department satisfaction, interpersonal relationship satisfaction of academic achievement in female nursing students. Data were collected from 159 female nursing students in B city and analyzed by t-test, ANOVA, Pearson correlation coefficient, and multiple regression using SPSS/WIN 22.0. The degree of academic achievement in female nursing students was 3.74±0.84. There were significant differences in academic achievement with career plan (t=2.672, p=.008), There was negative correlation between academic achievement and academic stress (r=-.371, p<.001), positive correlation between academic achievement and department satisfaction (r=.472, p<.001), interpersonal relationship satisfaction (r=.301, p<.001). The factors affecting academic achievement of the study subjects were academic stress (β=-.262, p<.001), department satisfaction (β=.403, p<.001), with an explanatory power of 26.3%. Through the result of this study, it is necessary to development various program that can improve academic achievement in female nursing students.

• The Korean Journal of Emergency Medical Services
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• v.27 no.1
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• pp.59-70
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• 2023

Purpose: This study was designed to identify the effects of social support, learning flow, and learning satisfaction on academic achievement in university students. Methods: This study involved university students who agreed to participate the investigation in D City using a structured online questionnaire from December 1, 2022 to December 31, 2022. Results: Social support, learning flow, learning satisfaction, and academic achievement had significant correlations. The influencing factors of academic achievement were age and learning flow, with an explanatory power of 20%. Conclusion: Further active management and attention are imperative for vulnerable students in high-age groups to search for the ways to improve learning flow.

• Journal of the Korean Society of School Health
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• v.32 no.3
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• pp.144-151
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• 2019

Purpose: The purpose of this study is to examine academic stress, social support and learning management system(LMS) utilization satisfaction of learners attending online graduate schools and understand the factors influencing their academic persistence. Methods: The participants were students of K online graduate school and the data of 143 students, in total, were collected from April to May in 2019. For data analysis, frequency analysis, x² test, t-test, F-test, Pearson's correlation and multiple regression analysis were conducted using SPSS ver. 23. Results: Academic stress, social support, and LMS utilization satisfaction were associated with academic persistence of online graduate students. The multiple regression analysis of the factors influencing academic persistence showed that the model was significant (p<.001) with an explanatory power of 23% and that significant factors influencing it were academic stress (β=-.23, p=.002), LMS utilization satisfaction (β=.31, p<.001) and jobs (β=.23, p=.002). Conclusion: Although the online graduate students' level of academic persistence was high, it is required to develop strategies to alleviate their academic stress and increase LMS utilization rate in order to increase their persistence to academic success. In addition, it is necessary to provide the foundation on which the utilization of major knowledge regarding jobs can be enhanced, reflecting the characteristics of online graduate students. Furthermore, this study is expected to contribute to the extension of professional and advanced education in response to social needs by developing a variety of online high education learning systems beyond time and space.