• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1360-1363
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• 1994

Epoxy resin insulator have good electrical properties (high electric strength, high resistivity, low dielectric loss) in addition to high mechanical strength, small dimensions and design versatility. Polymer insulator, however, are subjected to aging processes, caused by the surrounding atmosphere, which may lead to degradation of their properties. This paper describes the results of a important study on the artificial pollution test, Weather-Ometer properties and rotating wheel dip test of high voltage different aging insulators which are the most important factors for outdoor uses. Also, the objects of this paper are to (a)result of insulator under dry(wet) flashover voltage, (b)artificial pollution test of salt spay, (c)Accelerated aging test of Weather-Ometer, (d) wet and dry flashover voltage under rotating wheel dip test.

• Korean Educational Research Journal
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• v.40 no.2
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• pp.57-73
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• 2019

The study aimed at investigating the level of self-efficacy of science teachers towards student engagement. Although the general self-efficacy of teachers has been explored a lot but the efficacy of science teacher has not been explored more and student engagement is crucial towards understanding of science concepts. Therefore, the main purpose of the study was to find the self-efficacy of science teachers mainly towards three dimensions of student engagement (Behavioral, Cognitive and Emotional engagement). The study was carried with 150 secondary science teachers as Kathmandu. Secondary science teachers were found to be moderately high efficacious in all aspects of behavioral engagement of students except four aspects in which they showed moderate efficacy. Regarding the self-efficacy on cognitive engagement they were moderately efficacious in two aspects and were found to be moderately high efficacious in other all aspects. However, science teachers' self-efficacy was found to be moderately high. Teachers were found to be efficacious in making clasroom constructive, developing collaborative skill and high order thinking among the students. However in some aspects they were found less efficacious.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2525-2527
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• 2000

The analysis of distribution line faults is essential to the proper protection of power system. A high impedance fault(HIF) dose not make enough current to cause conventional protective device operating, so it is well known that undesirable operating conditions and certain types of faults on electric distribution feeders cannot be detected by using conventional protection system. In this paper, we prove that the nature of the high impedance faults is indeed a deterministic chaos, not a random motion. Algorithms for estimating Lyapunov spectrum and the largest Lyapunov exponent are applied to various fault currents detections in order to evaluate the orbital instability peculiar to deterministic chaos dynamically, and fractal dimensions of fault currents which represent geometrical self-similarity are calculated. Wavelet transform analysis is applied the time-scale information to fault signal. Time-scale representation of high impedance faults can detect easily and localize correctly the fault waveform.

• KIEE International Transactions on Electrophysics and Applications
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• v.11C no.4
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• pp.150-154
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• 2001

In this paper, we presented a novel structure of microstrip directional coupler for realizing the high directivity characteristic and tight coupling. The achievement of the high directivity with microstrip configuration was carried out by matching the even and odd mode effective phase velocities. By using 2-dimensional finite element (FE) calculations, the phase velocity for each mode and design parameters were extracted for given dimensions. Based on the extracted design parameter with phase-matched condition, we designed and fabricated 3dB and 4.7dB directional coupler at 2.0GHz. Experimental results of microstrip coupler show good performance with excellent isolation characteristics.

• Journal of the Korean Vacuum Society
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• v.8 no.3B
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• pp.257-261
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• 1999

The claw pump, one of oil-less dry pumps developed to solve problems found in vacuum systems pumped by oil-sealed rotary pumps, has been widely used separately or as a part of compound structure with a roots pump. The claw pump has some merits such as a high pumping speed, a high compression ratio, and relatively little heat generation. The high compression ratio of the claw pump is compression ratio, and relatively little heat generation. The high compression ratio of the claw pump is based on efficient sweeping action of the special type rotor and an intrinsic self-valving mechanism. The contour of the rotor with claw-type blade is designed basically to make two rotors revolve smoothly without touching with each other, and related dimensions are determined by required pumping speed, compression ratio, power demand and diameter of the rotor axis. In this paper the procedure of designing the rotor of the claw pump is described and factors influencing the pump performance are analyzed.

• Journal of the Korean Society of School Health
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• v.18 no.1
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• pp.1-14
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• 2005

Purpose: The purpose of this study was to identify the needs of health education in students, their parents and teachers in the elementary, middle and high schools and the current situation of health education class. Method: The subjects of this study were a total of 9450 persons including students, their parents and teachers from 279 schools throughout the country. They were selected through convenient sampling. Data were analyzed through $\chi^2$-test and ANOVA. Result: Students, their parents and teachers replied that 18 dimensions of health education class (DHEC) are necessary. The four DHEC - healthier life style, sex education, mental health and safety education - showed high educational needs in students, their parents, and teachers. High school students had higher educational need of 'symptom management for daily living' than elementary and middle school students. Students, their parents and teachers in elementary school had higher educational needs of 17 DHEC than those in middle and high school. The percentages of schools with health education class taught by health teachers were 99.2%, 75.5% and 66.0% respectively in elementary, middle and high schools. Health education was given mainly using physical education classes at elementary schools, and creative class hours at middle and high schools. In general, health education took 1-3 hours per week at elementary schools, and less than an hour at middle and high schools. Conclusion: Therefore, based on the results, systematic health education class should begin from elementary school to meet the need of health education in students, their parents and teachers, and further study should be made on the number of hours required and the amount of contents of 18 DHEC.

• Korean Medical Education Review
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• v.16 no.2
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• pp.67-76
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• 2014

Few studies have examined burnout among the faculty of medical schools in the Republic of Korea. The aim of this study was to determine the level of burnout and its associated factors among the faculty members of three medical schools in the Busan-Gyeongnam area, and to summarise the available literature on burnout. We conducted the survey using a validated questionnaire that incorporated the Maslach Burnout Inventory-Human Services Survey (MBI-HSS) as well as questions about demographic characteristics, working experience, health, lifestyle, most time spent and most difficult work, and suicidal ideation and job quitting ideation of the survey participants. MBI-HSS scores were analysed in the three dimensions of emotional exhaustion (EE), depersonalization (De), and personal accomplishment (PA). Through the survey, the 186 professors, 49% among the total, provided data which were included in the present analysis. More than thirty per cent (37.1%) of the professors reported at least 1 symptom of burnout. For burnout dimensions, 11.8% of the respondents scored high for EE burnout, 25.3% for De, and 14.5% for PA, with 1.6% scoring high on all three dimensions of burnout. High burnout was found to be strongly associated with several of the variables under study, especially hours worked per week, self-rated health, career (range, 4 to 9 years), and age (range, 50 to 59 years). The EE score was highest for the professors who chose 'patient care' as the most difficult type of work. This study showed that just over one-third of professors have at least 1 symptom of burnout and working more hours per week, short length of work (years), and especially suicidal ideation seem to be associated with the burnout of medical school faculty members in the Busan-Gyeongnam area. In summary, a greater risk of burnout of physicians (including medical professors) seems to be associated with specialties at the front line of care, working more hours per week, work-life imbalance, low self-efficacy, depression, and conflicts with colleagues and patients.

• Science of Emotion and Sensibility
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• v.26 no.2
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• pp.39-52
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• 2023

According to the core affect theory, affect consists of two independent dimensions of valence and arousal. Previous studies have found that various types of stimuli, such as pictures, videos, and music, are mapped onto the core affect space. However, the research on affect using gustatory stimuli has not been explored sufficiently. This study investigated whether the affects elicited by tastes could be mapped onto the core affect space. Stimuli were selected based on two factors (taste types and intensity). Participants were presented with each stimulus, evaluated the tastes, and rated their affective responses on taste and emotion scales. The data were analyzed using repeated-measures ANOVAs and multivariate analyses (multidimensional scaling and classification). The results of univariate analyses indicated that participants felt positive for sweet stimuli but negative for bitter and salty. Furthermore, participants reported high arousal with high intensity. Multidimensional scaling revealed that taste stimuli are also represented on the core affect dimensions. Specifically, it was confirmed that in the first dimension, sweetness was represented as a positive affect, while bitter and salty tastes were represented as a negative affect. In the second dimension, bitterness was represented as low arousal and sourness as high arousal. Classification analyses confirmed that the taste was identified consistently based on the affective responses within and across participants. This study showed that the taste stimuli in daily life are also located on core affect dimensions of valence and arousal.

• 한국노년학
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• v.29 no.1
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• pp.275-289
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• 2009

The purpose of this study is to explore effective factors of elderly people's overall death anxiety and sub-dimensions of death anxiety. The subjects were 156 elderly people in S City, Gyeonggi-Do gathered by convenience sampling. This study collected data by interviewing the elderly who agreed to participate in the study and then analyzed it using SPSS 12.0 through descriptive statistics, the t-test, F-test, Sheffe-test, correlation analysis, and multiple regression. The respondents' overall death anxiety score was 2.61(±.47), and 'anxiety in the dying process'(2.94) had the highest points among sub-dimensions. Effective factors of overall level of death anxiety among the elderly were 'age' (β=-.18, p=.015), 'education' (β=-.16, p=.045), and 'economic status' (β=-.26, p=.003). In sub-dimensions, the elderly who were female, relatively young, and had low economic status showed high 'anxiety in the dying process'. As for 'anxiety over what will happen after one's death', the elderly who were relatively young, and had low economic status had high scores. Finally, on 'the loss of existence', the elderly who had poor relationships with their families had high scores.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.197-201
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• 2007

Vibration characteristics of an annular cylindrical fuel rod, which was proposed as a candidate design of fuel's cross section for the ultra-high burnup nuclear fuel, according to the cross-sectional dimensions and the number of supports or the span length were analytically studied. Finite element(FE) modeling for the annular cross sectional fuel was based on the methodology, that have been proven by the test verification, for the conventional PWR nuclear fuel rod. A commercial FEA code, ABAQUS, was used for the FE modeling and analysis. A planar beam element (B21) that uses a linear interpolation was used for the fuel rod and a linear spring element for the spring and dimple of the SG. Natural frequencies and mode shape were calculated according to the preliminary design candidates for the fuel's cross sectional dimension and the number of span. From the analysis results, the design scheme of the annular fuel compatible to the present PWR nuclear reactor core was discussed in terms of the number of supports and fuel's cross section.