http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Fabrication and Electrical Properties of PZT/BFO Multilayer Thin Films
Seo-Hyeon Jo,Sung-Pil Nam,이성갑,이승환,이영희,Young Gon Kim 한국전기전자재료학회 2011 Transactions on Electrical and Electronic Material Vol.12 No.5
Lead zirconate titanate (PZT)/ bismuth ferrite (BFO) multilayer thin films have been fabricated by the spin-coating method on Pt(200 nm)/Ti(10 nm)/SiO_2(100 nm)/p-Si(100) substrates using BiFeO_3 and Pb(Zr_(0.52)Ti_(0.48))O_3 metal alkoxide solutions. The PZT/BFO multilayer thin films show a uniform and void-free grain structure, and the grain size is smaller than that of PZT single films. The reason for this is assumed to be that the lower BFO layers play an important role as a nucleation site or seed layer for the formation of homogeneous and uniform upper PZT layers. The dielectric constant and dielectric losses decreased with increasing number of coatings, and the six-layer PZT/BFO thin film has good properties of 162 (dielectric constant) and 0.017 (dielectric losses) at 1 kHz. The remnant polarization and coercive field of three-layer PZT/BFO thin films were 13.86 μC/cm^2 and 37 kV/cm respectively.
PZT(80/20)/BFO 이종층 박막의 코팅횟수에 따른 전기적 특성
조서현(Seo-Hyeon Jo),김대영(Dae-Young Kim),이태호(Tae-Ho Lee),남성필(Sung-Pill Nam),이성갑(Sung-Gap Lee),이영희(Young-Hi Lee) 대한전기학회 2010 대한전기학회 학술대회 논문집 Vol.2010 No.11
In this study, PZT(80/20)/BFO heterolayered thin film were fabricated by sol- gel method. which were spin-coated onto the Pt/Ti/SiO₂/Si substrate alternately using PZT(80/20) and BFO metal alkoxide solutions. With increasing the number of layer, the dielectric properties of thin films were improved. The relative dielectric constant and the dielectric loss of the 6-layer thin film were about 482 and 0.033%, respectively.
랜덤상태의 E-유리 단섬유 강화 불포화 폴리에스터 기반 수지 복합재료의 물성 - E-유리 단섬유의 길이와 함량 및 적층수의 영향 -
박진명,박영광,이영희,서대경,이장훈,김한도,Park, Jin-Myung,Park, Young-Gwang,Lee, Young-Hee,Seo, Dae-Kyung,Lee, Jang-Hun,Kim, Han-Do 한국염색가공학회 2015 韓國染色加工學會誌 Vol.27 No.3
To develop automobile parts, the unsaturated polyester based matrix resin(PR)/reinforcement(randomly oriented chopped E-glass fiber, GF) composites were prepared using sheet molding compound(SMC) compression molding. The effects of GF length(0.5, 1.0 1.5 and 2.0inch)/content (15, 20, 25, 30wt%) and number of ply(3, 4 and 5) on the specific gravity and mechanical properties of PR/GF composites were investigated in this study. The optimum length of GF was found to be about 1.0inch for achieving improved mechanical properties(tensile strength and initial modulus). The tensile strength and initial modulus of composites increased with increasing GF content up to 30wt%, which is favorable content range for SMC. The specific gravity, tensile strength/initial modulus, compressive strength/modulus, flexural strength/modulus and shear strength increased with increasing the number of ply up to 5, which is the maximum number of ply range for SMC. The effectiveness of ply number increased in the flexural strength > shear strength > compressive strength > tensile strength.
공업계열 특성화고 학생들의 기술의 본성(NOT)에 대한 인식 탐구 - 과학기술사 수업을 중심으로 -
서동현 ( Dong Hyun Seo ),이영희 ( Young Hee Lee ),조헌국 ( Hunkoog Jho ) 韓國生物敎育學會 2017 생물교육 Vol.45 No.1
The purpose of this study was to investigate students` understanding about the nature of technology (NOT) and examine the differences of their understanding of NOT after the instruction related to science and technology course. The participants in this study were 290 of 10<sup>th</sup> grade students in a technical high school in the metropolitan area, and took the course of science and technology developed based on the 2009 revised national curriculum. The students were asked to answer the questionnaire by Liou (2015). His framework for NOT was composed of six domains: technology as artifacts, technology as an innovative change, the current role of technology in society, technology as a double-edged sword, history of Technology, and technology as a science-based form. The results showed that the students showed diverse viewpoints about NOT, and that they were good at understanding about technology as an innovative change and history of technology. As well, their overall performances in NOT were well improved by the instruction since the difference between pre- and post-test was significant (p<.05). Especially, the difference in technology as a science-based form was higher than any other domains. On the other hand, they did not show significant gender differences in the understanding of NOT but majors significantly did. Thus, this study suggested some pedagogical implications for enhancing NOT for technical high school students.
특성화고 학생들의 과학의 본성(NOS) 이해를 위한 과학기술사 수업 프로그램의 개발 및 적용
서동현 ( Dong Hyun Seo ),이영희 ( Young Hee Lee ),조헌국 ( Hunkoog Jho ) 경북대학교 과학교육연구소 2017 科學敎育硏究誌 Vol.41 No.1
본 연구는 공업계열 특성화고 학생들을 위한 과학기술사 수업 프로그램을 개발하고 적용함으로써 과학의 본성에 대한 이해에 미치는 교육적 효과를 조사하였다. 프로그램은 고등학교 융합 과학 및 물리 I의 교육과정을 바탕으로 6개의 과학기술사 주제로 개발되었으며, 경기도에 위치한 공업계열 특성화고 학생 290명을 대상으로 적용되었다. 본 연구의 방법은 단일 그룹 사전-사후 검사로 설계되었으며. 학생들의 과학의 본성에 대한 이해를 조사하고자 프로그램 적용 전후에 설문을 실시하여 그 검사 결과를 SPSS 23을 이용하여 통계 분석을 실시하였다. 과학의 본성에 대한 설문도구는 선행연구에서 개발된 4가지 영역의 과학의 본성 개념 틀(Lee, 2014)을 수정 보완하여 사용하였다. 본 연구의 결과는 다음과 같다. 첫째, 공업계열 특성화고 학생들의 과학의 본성에 이해에 대한 사전·사후 비교 결과, 과학기술사 수업 프로그램이 학생들의 이해에 효과가 있는 것으로 나타났다. 둘째, 과학기술사 수업 프로그램의 효과는 특성화고 학생들의 성별 및 전공에 따른 차이는 없는 것으로 나타났다. 셋째, 과학의 본성 4가지 영역간의 상관관계 분석에 의하면, 4가지 영역들은 모두 상호 높은 상관관계가 있는 것으로 나타났으며, 특히 각 개별 영역들은 모두 과학과 기술, 그리고 사회와의 상호작용에 대한 과학의 본성 측면과 상관관계가 있는 것이 발견되었다. 한편, 과학기술사 수업 프로그램은 구체적으로 어떻게 학생들의 과학의 본성에 대한 이해에 효과가 있는지에 대한 후속 연구가 필요하다. The purpose of this study was to develop a program for the history of science and technology in order for the technical high school students to understand the nature of science (NOS). The program was composed of the six topics based on the textbooks such as convergence science and physics I, and was taught to 290 10th graders at a technical high school located in the metropolitan area. The questionnaire about NOS was asked the students before and after the instruction, so as to investigate the effect of the program on improving their understandings of NOS. The analysis followed t-test and ANOVA using SPSS 23.0 for Windows program. The questionnaire based on the conceptual framework of the four themes of the NOS (Lee, 2014). The research findings were as follows. First, the program was effective in improving their understanding of NOS since the t-test result was significant statistically for the overall domains of NOS (р<.01). Second, there was no significant gender differences in the understanding of NOS among technical high school students (р<.05), neither did their majors (р<.05). Third, all domains in NOS were statistically correlated (р<.01), and in a particular, each domain was consistently correlated with the aspect of the nature of the interactions among science, technology, and society. Hence, the further studies should be conducted to examine how the history of science and technology effects the understanding of the NOS and how the domains in NOS affected each other.