• Title/Summary/Keyword: Self field effects

Search Result 341, Processing Time 0.024 seconds

Critical Current Degradation Analysis in HTS Pancake Coil due to Self Field Effects

  • Nah, Wan-Soo;Joo, Jin-Ho;Yoo, Jai-Moo
    • Progress in Superconductivity
    • /
    • v.1 no.1
    • /
    • pp.68-72
    • /
    • 1999
  • Since the discovery of high Tc superconductors, great efforts have been focused to develop high performance HTS magnets for the ultimate applications to power system devices. Magnet designers, however, have had difficulties in the estimation of the maximum operating current of the designed magnet from the tested short sample data, due to the degradation of the critical current density in the magnet. Similar story applies to the HTS electrical bus bar. It has been found that the critical current of Bi-2223 stacked tapes is much less than the total summation of critical currents of each tape, which is mainly attributed to the self magnetic fields. Furthermore, since the critical current degradation of Bi-2223 tape is greater in the normal magnetic field (to the tape surface) than in the parallel one, detailed magnetic field configurations are required to reduce the self field effects. In this paper, we calculate the self field effects of a stacked conductor, defining self field factors of normal and parallel magnetic fields to the tape surface. Finally, the critical current degradations in the HTS magnet are explained by the introduced self field factors of the stacked conductor.

  • PDF

Analysis of Self Magnetic Field Effects in a Bi-2223 Stacked Superconducting Bus Bar (Bi계 고온 초전도 선재 부스바에서의 자기 자장 해석)

  • Kang, Hyoung-Ku;Nah, Wan-Soo;Joo, Jin-Ho;Yoo, Jai-Moo;Oh, Sang-Soo;Ryu, Kang-Sik
    • Proceedings of the KIEE Conference
    • /
    • 1998.07a
    • /
    • pp.302-304
    • /
    • 1998
  • Self magnetic field in a Bus bar usually degrades the critical current in it. Actually the total critical current of a Bus bar is not the same as the sum of total critical current of each stacked HTS tape. This is due to the self field effects in a bus bar. To reduce the degradations of critical current in a bus bar, we need to analyze the self field distributions in a bus bar. Conceptually, by rearranging the each stacked tapes, the self field effects can be minimized. In this paper, we calculate the self magnetic field distributions across a bus bar analytically, with the variations of the relative angle of the two conductors in a go-and-return pair. As a result, we suggest that the optimum relative angle exist which minimize the self field effect in a bus bar.

  • PDF

Association between self-esteem, critical thinking disposition, and field practice stress of dental laboratory technology students (치기공과 학생의 자기존중감, 비판적 사고성향 및 현장실습 스트레스 간의 연관성)

  • Kang, Wol;Jang, Yeon
    • Journal of Technologic Dentistry
    • /
    • v.44 no.3
    • /
    • pp.81-88
    • /
    • 2022
  • Purpose: This study was conducted to verify the effects of self-esteem and critical thinking disposition on dental laboratory technology students' field practice stress. Methods: The subjects of the study were 198 dental laboratory technology students with clinical practice experience located in Gyeongsangbuk-do and Gyeongsangnam-do. The collected data were analyzed by t-test, ANOVA, correlation analysis, and linear regression analysis using IBM SPSS Statistics ver. 22.0 (IBM). Results: The average self-esteem, critical thinking disposition, and field practice stress scores were 3.76, 3.50, and 2.40, respectively. There was a significant correlation between self-esteem, critical thinking disposition, and field practice stress. It was found that the higher the self-esteem, the lower was the field practice stress. On the contrary, among the sub-items of critical thinking disposition, when intellectual fairness increased, the field practice stress decreased; however, when healthy skepticism increased, the field practice stress increased. Conclusion: Self-esteem and critical thinking disposition were both found to have a substantial effect on field practice stress. Therefore, various educational programs need to increase self-esteem and cultivate critical thinking skills for a successful field practice and field practice stress relief of laboratory technology students.

Self Field Effect Analysis of Bi-2223 Tape-Stacked-Cable With Constant Current Density Assumption

  • Nah, Wansoo;Joo, Jinnho
    • Transactions on Electrical and Electronic Materials
    • /
    • v.1 no.1
    • /
    • pp.12-16
    • /
    • 2000
  • In this paper, we analyze self field effects of Bi-2223 tape-stacked cable assuming constant current density in the cross section of stacked cable. Generally, the critical current of Bi-2223 tape-stacked-cable in much less than the total summation of critical currents of each tape, which is mainly due to the self magnetic fields of the cable itself. Therefore, to predict the critical current of Bi-2223 tape-stacked-cable, we needs to analyze the self filed effects on the stacked cable as well as critical current density data(J$\_$C/) of one tape. To make it more complex, the critical current degradation of Bi-2223 tape is an-isotropic; the critical current is lower in the normal magnetic field(to the tape surface) than in the parallel field. In the paper, a novel approach to predict the critical current of a Bi-2223 tape-stacked-cable from a J$\_$C/-B curve of one tape is presented with the assumption of constant current density across the stacked cable, The approach basically includes the load analysis of the stacked tapes, and its usefulness is confirmed by the experimental data.

  • PDF

Retro-self-focusing and pinholing effect in a refractive index grating

  • Lee, Jae-Cheul
    • Journal of the Optical Society of Korea
    • /
    • v.1 no.1
    • /
    • pp.23-25
    • /
    • 1997
  • In this paper we will show theoretically that a refractive index grating exhibits a retro-self-focusing effect and an accompanying pinholing effect under the Gaussian intensity distribution of an incident optical field. Those effects result from an effective wave number change of the medium due to the intense optical field.

The Mediating Effects of Self-efficacy between Metacognition and Learning flow in College Students in Healthcare Field (보건의료분야 대학생들의 메타인지와 학습몰입 간의 관계에서 자기효능감의 매개효과)

  • Han, Ju-Rang;Kim, Jang-Mook
    • Journal of Digital Convergence
    • /
    • v.15 no.6
    • /
    • pp.273-282
    • /
    • 2017
  • The objective of this study was to verify the mediating effects of self-efficacy between metacognition and learning flow in college students in healthcare field. Participants were 300 college students. Self-administered questionnaire data were collected from November 21 to December 2, 2016. Data were analyzed using descriptive statistics, t-test, ANOVA, Pearson correlation coefficients and hierarchical regression analysis with the SPSS/WIN 23.0 program. Results are as follows. Metacognition had positive effects on learning flow(${\beta}=.678$, p<.001). Self-efficacy had a partial mediating effect on the relationship between metacognition and learning flow. The findings of study showed that metacognition was very important for enhancing learning flow and self-efficacy influenced these relationship. This study suggested that it is important to develop and implement teaching and learning strategies with improved metacognition in healthcare field.

Effects of self-management on psychological happiness in throwers (투척선수들의 자기관리가 심리적 행복감에 미치는 영향)

  • Lee, Myung-Sun;Lee, Moon-Sook
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.12 no.3
    • /
    • pp.1128-1135
    • /
    • 2011
  • The purpose of this study was to identify the effects of field athletes' self-management on their psychological happiness. The subjects of the study were 184 athletes (male=82, female=102) who participated in the 91th National Athletes Meeting. All statistical analyses and description methods were computed by SPSS window 18.0. The discriminant analysis was used to find effects of self-management on their psychological happiness, ANOVA and Multiple regression. The results of this study were as followings: Frist, there was not significant difference to The Relationship between social-demographical variables and self-management, their psychological happiness. Second, self-management had a significant effect on psychological happiness. Based on the results, Field athletes's self-management has a positive effect on their psychological happiness.

Differences in psychological effects of nail-care service according to consumer's self-esteem (소비자의 자아존중감에 따른 네일 서비스의 심리적 효과의 차이)

  • Seo, Kyung Ja;Kim, Mi Young
    • The Research Journal of the Costume Culture
    • /
    • v.26 no.4
    • /
    • pp.519-530
    • /
    • 2018
  • Nail-care services are growing rapidly. If causes for the increase in nail-care service consumption is diversion or self-satisfaction, we can speculate that consumers perform self-care through nail-care services. Nail-care-service consumption should be allowed to increase because of the positive psychological effects such as improving mood or alleviating depressed emotions. Moreover, the psychological effects of nail-care services differ according to consumers' tendencies. Therefore, this study divides the types of consumers, to investigate whether there is a difference in the psychological effects of nail-care services depending on the types. This study used the questionnaire survey method. Results of the study revealed that the sub-factors of self-esteem, extracted as two factors, were "personal self-esteem" and "social self-esteem". Consumers were classified according to the sub-factors of self-esteem into four groups. There were differences in the psychological effects of nail-care services according to these four groups. It was found that all groups had psychological effects above the average value. This result indicates that only the degrees of psychological effects differ in accordance with the types of self-esteem, and that psychological effects generally play a large role in all types. Since psychological effects were positive for everyone regardless of their self-esteem, utilizing nail-care services considerably reduces the depression and anxiety of modern people. Nail-care services expected to become the basis of the nail therapy field.

The Effects of College Life Adaptability on Career Preparation Behaviors of College Students: Mediating Effects of Major Satisfaction, Job Stress, and Self-Directed Learning

  • Il-Hyun, Yun
    • International Journal of Advanced Culture Technology
    • /
    • v.10 no.4
    • /
    • pp.245-254
    • /
    • 2022
  • This study is a study to empirically verify the mediating effect on college life adaptation and career preparation behavior of college students. The purpose of this study is to empirically analyze the multi-mediated effects of major satisfaction, job stress, and self-directed learning. For this study, 216 university students were enrolled. For the collected data, SPSS Process macro was used. The result is as follows. First, there were multiple parallel mediating effects and multiple serial mediating effects on major satisfaction, job stress, and self-directed learning between college life adaptability and career preparation behavior. Second, the path of simple mediation and double mediation effect was found between college life adaptation and career preparation behavior. Based on the research, the necessity of revitalizing the program for revitalization of teaching activities and industry-academic cooperation activities in the major field and improvement of career preparation behavior and university life adaptation ability and follow-up research were suggested.

Impact of School Career Assistance on Improving Self-efficacy: Moderating Effects of Grit and Regulatory Focus

  • SangWoo Hahm
    • International Journal of Internet, Broadcasting and Communication
    • /
    • v.16 no.1
    • /
    • pp.191-202
    • /
    • 2024
  • Self-efficacy is a major factor related to performance and needs to be improved in business and education field. This study explains the effectiveness of school career assistance to improve college students' self-efficacy. Furthermore, it demonstrates the moderating effects of grit and regulatory focus (promote and prevention). School career assistance is based on group support, and moderating variables in this paper are individual characteristics. In these group and individual dimensions, if the effectiveness of school career assistance varies depending on individual characteristics, schools will be able to establish self-efficacy improvement strategies more appropriate for individual students. School would understand individual characteristics such as grit and regulatory focus, then could make individual strategy for enhancing self-efficacy and performance. Hence, it is expected that the performance of school and student will improve through the self-efficacy improvement plan presented in this study.