• Proceedings of the KIPE Conference
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• 2019.07a
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• pp.348-349
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• 2019

본 논문은 전기자동차용 8.1kW/L의 높은 전력밀도를 갖는 저전압 DC-DC 컨버터(Low-voltage DC-DC converter, LDC)의 설계 방법을 제안한다. 넓은 전압범위에서 높은 전력밀도를 성취하기 위해 위상천이 풀-브릿지(Phase Shift Full-Bridge, PSFB) 컨버터의 2차측 토폴로지 후보군의 비교를 통해 전류-더블러 토폴로지로 토폴로지가 선정되었다. 또한 자속 상쇄 기법이 적용된 매트릭스 변압기를 적용한 PSFB 컨버터와 냉각기의 구조설계를 통해 8.1kW/L의 전력밀도를 달성하였으며 1.8kW 시작품을 제작하여 성능을 검증하였다.

• Journal of Korean Philosophical Society
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• v.142
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• pp.221-241
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• 2017

I try to elucidate the essence of cinematic art in terms of Nietzsche's physiological philosophy of art. According to Nietzsche, the mise-en-$sc{\grave{e}}nes$ in the film are expressions of willingness to the power of the author, the director. These are not re-imitations of the imitations with Platonic measure, sinker, number, but framing the elan vital Erde, die $urspr{\ddot{u}}ngliche$ Vorstellung with the director's body-camera. In this context, the film is essentially die Kunst des Lebens, in which the body and the earth are mediated by cameras. Therefore, it is not the eyes or the head, but the body that is necessary to appreciate film art. But the body at this time does not mean the heavy body of Hollywood standard audiences manipulated, controlled, or transformed by capital. We should stand in front of the film work with body shaking between trauma and Rausch, a dancing body, and a light and fresh body. Only by watching film with the body, can we achieve the small revolutions in everyday life. For example, if we watch $B{\acute{e}}la$ Tarr's film The Turin Horse in such a way, we can no longer be the dwarfed human beings, der Herde-Mensch. Also, $B{\acute{e}}la$ Tarr's mise-en-scene will make us realize why Nietzsche had said that there is art to us not to be destroyed by the platonic truth.

• Journal of the Korean earth science society
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• v.22 no.5
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• pp.350-359
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• 2001

The purpose of this study is to develop theme-based integrated science unit by the interdisciplinary approach and to analyze it's effects on the science achievement and the attitude towards science learning. 'Interaction' and 'Stability' were selected as the integrated themes, and the main concept and subconcept in relation to the themes were extracted from the four areas of science, and the learning contents were constructed in the integrated ways. While the main concept have relevance to subconcept in the interaction, the main concept have little relevance to subconcept in the stability. Therefore, the stability was to fit with middle school integrated science theme, but the interaction was not. The theme-based integrated science units developed was implemented in middle school, and the results are follows. First, the science achievement of group of theme-based integrated science teaching is significantly higher than those of group of traditional teaching. Second, the scores of the test of attitude toward science learning of the group of theme-based integrated science teaching is significantly higher than those of group of traditional teaching. Third, the students' perception of theme-based integrated science teaching was positive. The students have participation, interest, motivation in theme-based integrated science teaching, and students have difficulty in learning theme-based integrated science teaching.

• Communications of Mathematical Education
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• v.19 no.1 s.21
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• pp.69-100
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• 2005

이 연구는 내신성적이 우수함에도 불구하고 수능성적이 저조한 학생들이 문제 해결과정에서 나타내는 특성과 수학불안 요인을 분석하는데 있다. 연구의 대상은 인천시 5고등학교 자연계열 2학년 학생 중 내신성적이 상위 10%안에 드나 수능성적(모의수능성적)은 그렇지 못한 학생 5명이고, 이들의 수학적 성향, 수학 성취도, 개인별 특성 등에 대한 사전 면담자료, 문제풀이과정에 대한 사후 심층면담자료, 현장노트, 수학불안검사를 바탕으로 그들의 특성과 수학불안 요인을 분석한 결과는 다음과 같다. (1) 내신성적은 좋으나 수능성적이 저조한 학생들의 수학 문제 해결 과정에서 나타나는 특성은 수학전 영역에서의 개념부족, 공식암기 부족 등으로 인하여 문제풀이계획을 세우지 못하거나 설사 문제를 푼다고 해도 계산 실수, 착각, 부주의 등으로 인해 정확한 답을 구하지 못하는 것으로 나타났다. (2) 내신성적은 좋으나 수능성적이 저조한 학생들은 어느 정도의 수학 불안은 가지고 있었다. 불안의 요인은 개념부족, 응용력 부족 등 개인적 인지능력에 의한 저조한 수학 성취수준과 수학 공부시간 부족, 풀이시간 부족 등의 환경적 요인에 때문인 것으로 밝혀졌다. 특히 수학개념이 부족한 학생일수록 수학불안 현상이 심하게 나타났다. 따라서 이들 학생들의 수학 문제풀이 과정 중에 나타나는 계산 실수, 부주의, 착각은 그들의 수학 자신감에 많은 악영향을 미치게 되므로, 교사가 이를 그냥 방관할 것이 아니라 적극적으로 확인하고 지도해줄 필요가 있다. 또 교실 수업에서도 수능시험에서 다루고 있는 수학 내적, 외적 문제해결문제, 추론문제, 응용문제, 통합문제에 대한 문제풀이 경험을 하게하여 수학불안을 해소해줄 필요가 있다.)값을 보였으나, 10,000Hz의 높은 측정주파수에서는 더 큰 $E_a$값을 나타냄으로서 반응온도변화에 민감함을 보여주었다.원으로부터 부유물을 증가로 사료되었으며, 이에 대한 대책마련이 시급한 것으로 사료되었다. 수질이 휴양용수로서 사용하는 데에 적합하도록 충분한 차집시설과 환경 기초시설의 설치 운영이 필요할 것으로 판단된다.TEX>$K_s$값이 높고 $V_m/K_s$비율은 낮아 수게에서 질소가 저농도 일 때에는 다른 미세조류와 비교하면 경쟁력이 떨어지고 질소에 대한 기질 친화력은 약한 것으로 나타났다. 낙동강 하류지역에서 M. aeruginosa가 대발생하는 시기에 수중 영양염의 농도 변동은 M. aeruginosa의 영양생리 kinetics 특성과 잘 부합하는 것으로 나타났다.부분을 보완하기 위한 연구가 이루어져야 할 것으로 보인다. 연마방법 간에 상호 연관성이 없었다. FE-SEM관찰에서 레진전색제를 적용한 후의 표면은 모든 군에서 대체적으로 평활한 표면을 나타내었다. 4. 동일한 복합레진과 연마방법으로 처리된 군에서 레진전색제 적용 전과 후의 표면조도 값은 M1B군이 M1군보다, S1B군이 S1군보다 통계학적으로 높게 나타났으며, M4B군과 M5B군은 각각 M4군과 M5군 보다. 그리고 S5B군은 S5군 보다 통계학적으로 낮게 나타났다 (p<0.05). 본 연구를 종합하여 보면, 복합레진의 종류에 따라 표면조도의 순서는 다르게 나타났고, polyester strip 하에서 복합레진이 중합된 경우 가장 낮은 표면조도 값과 평활한 표면을 제공하였으며 전반적으로 anishing bur는 가장 높은 Ra값과 거친 표면을 제공하였다.

• Journal of The Korean Association For Science Education
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• v.30 no.4
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• pp.498-518
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• 2010

This study analyzed the characteristics of organization scheme and the levels of core concepts in science textbooks used in Korea, Singapore, and Taiwan, which have shown superior achievement according to the TIMSS 2007. Science textbooks in Korea clearly divide the fields of Energy, Matter, Biology, and Earth, presenting the fields in nearly equal proportion in each grade. In the case of Singapore, science textbooks take an integrated content approach, combining concepts from several fields under a single theme. Science textbooks in Taiwan present a single content field in each unit. Also, because each grade engages in a specific field intensively, there are many cases in which concepts related to a single field are studied in a single grade. In view of levels of core concepts, Singapore or Taiwan showed higher achievement than Korea in themes of 'Cell and their Functions', 'Ecosystems', and 'Human Health' under the TIMSS 2007 biology field. Singapore introduces core concepts for these themes in lower grades compared to Korea and presents them repeatedly in several grades. In Taiwan, there are many cases in which these core concepts are taught only once during the course of $3^{rd}$ to $8^{th}$ grade, but the explanations are presented at a level that is suitable to TIMSS 2007 assessment objectives. Considering the results of this analysis, there is a need to reconsider the division of content fields and methods of presenting core concepts in the science textbooks of Korea.

• Journal of Christian Education in Korea
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• v.61
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• pp.203-232
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• 2020

The purpose of this study was to analyze various factors that influence the academic life of students through a theoretical review. As a result of the analysis, sub-factors were derived to diagnose the factors. From the study's findings, principles and models for developing learning status diagnosis tools were designed. The study first, based upon the competencies of university students, university life, students' low academic achievement, and academic probation studies, confirmed what factors affect student learning and from them derived a set of sub-factors. The setting dimension was divided into psychology, learning, and career factors, while also including a factor of faith for Christian university students. Next, in the draft model, sub-factors were constructed for each factor: faith maturity and faith training in the faith factor, positive thinking, emotion regulation, and self-esteem in the psychology factor, self-directed learning ability, learning motivation, and learning strategies in the learning factor, and career reflection, career exploration, career management, and career barriers in the career factor. By using the Delphi method, the final model of learning status diagnosis was confirmed. As a result, we completed the model comprised of nine sub-factors in four parts. A follow-up study should be conducted that examines learning status diagnosis tools development research.

• Journal of Korean Home Economics Education Association
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• v.34 no.4
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• pp.57-75
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• 2022

The purpose of this study was to analyze the contents of middle school technology and home economics textbooks(family life area) that reflect the school career education goals and achievement standards in the 2015 revision of the Technology and Home Economics curriculum. Five different textbooks on middle school technology and home economics written based on the 2015 curriculum were selected and the school career education goals and achievement standards developed by the Korea Research Institute for Vocational Education and Training (2021) were used as a framework for textbook analysis. The results are as follows. First, the units that cover career education contents the most were 'life design and career choice(n=87)', 'developmental characteristics of adolescents(n=36)', and 'low birth rate, aging society, and work and family balance(n=31)'. The major contents of career education covered in technology and home economics textbooks(family life area) were 'search for various professionals(24.30%)', 'exploration of the changes in the future society(22.74%)', and 'exploration of the changes in the job world(18.66%)'. Thus it was found that the goals and achievement standards of school career education are evenly reflected in the middle school technology and home economics textbooks(family life area) based on the 2015 curriculum.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.17 no.2
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• pp.141-151
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• 2022

This exploratory study was conducted to derive the components of digital entrepreneurship by targeting the experts related to Information and Communication Technology (ICT). Through the review of previous studies and Delphi analysis, the major components of digital entrepreneurship were derived into the 'digital entrepreneurial orientation area' and the 'digital technology competency area'. The components of digital entrepreneurship are innovativeness, proactiveness, risk-taking, desire for achievement, ability to identify digital business opportunities, digital technology utilization capability, digital operation process establishment capability, digital technology development capability, digital technology acceptance, information exchange, and cooperation network establishment, digital-based customer acquisition and management was presented. The importance and execution of success factors were measured through IPA analysis. The first quadrant(keep up the good work) includes proactiveness, ability to identify digital business opportunities, and ability to establish digital business processes. The second quadrant(concentrate here) includes innovativeness, digital technology development capability, and digital technology acceptance. The third quadrant(low priority) includes risk-taking, desire for achievement, digital technology utilization capacity, and digital-based customer acquisition and management. The fourth quadrant(possible overkill) includes information exchange and cooperation network establishment. This study is meaningful in that it presents the concept and components of digital entrepreneurship for digital entrepreneurs that can be applied in Korea.

• Journal of The Korean Association of Information Education
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• v.10 no.1
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• pp.67-74
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• 2006

This study attempts to analyze fifteen computer textbooks for the first and second grades. The textbooks were analyzed by the following characteristics: goals, contents, and formative evaluation. Evaluation criteria from previous works were selected for advantages and identify the problems. In addition, advice for teachers using these books is proposed. The results of the analyses of current computer textbooks are the following: Firstly, in the area of goals and contents, most textbooks clearly define learning goals for each unit. Secondly, in the area of content, some textbooks have a large volume for first and second grade students, and they do not provide enough integration with other subjects. Finally, they do not provide formative evaluation to achieve for goals.

• Magazine of the Korea Concrete Institute
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• v.11 no.1
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• pp.141-148
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• 1999

Recently, high performance concrete developed has a good quality at fresh and hardened state, but high binder contents results in spending much money on manufacturing and many cracks by drying and autogenous shrinkage, Therefore, in this paper, not only prevention of cracks caused by drying and autogenous shrinkage, but improvement of quality and accomplishment of economy by applying F.A(fly ash), S.F(silica fume) and CSA(calcium sulfa aluminate) expansive additives as an inorganic admixtures in W/B 35% are discussed. According to the experimental results, when 5% of CSA expansive additives and 15:5(F.A:S.F)are replaced at unit cement content, high performance concrete with both good fluidity at fresh state and high compressive strength, compensation of drying and autogenous shrinkage at hardened state are accomplished.