• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2010년도 추계학술대회 논문집
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• pp.537-537
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• 2010

High precision sensing is very important in various technologies. Especially, it is more important when it were applied to nano/micro meter level's sensing like AFM, storage, etc. And capacitive sensing is widely used method. To improve the measurement efficiency, many signal conditioners were studied and one of them was surface acoustic wave (SAW) device. SAW device is very widely used as a high frequency bandwidth filter. Due to the reflective characteristic of high frequency, the response of SAW device contains both propagative and reflective signal at the external impedance. In this paper, we used SAW device as signal conditioner of capacitive sensor. And high precision gap measurement was executed using capacitive load. Reference signal was reflective SAW response and the magnitude at the center frequency of SAW device by the change of impedance was checked. Finally, the attainable gap resolution was determined.

• Applied Science and Convergence Technology
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• 제25권4호
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• pp.73-76
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• 2016

Multi-layer films of $SiN_x/SiO_x$/InSnO with anti-reflective effect were grown by new-concept plasma enhanced chemical vapor deposition system (PECVD) with hybrid plasma source (HPS). Anti-reflective effect of $SiN_x/SiO_x$/InSnO was investigated as a function of ratio of $SiN_x$ and $SiO_x$ thickness. Multi-layers deposited by PECVD with HPS represents the enhancement of anti-reflective effect with high transmittance, comparing to the layers by conventional radio frequency (RF) sputtering system. This change is strongly related to the optical and physical properties of each layer, such as refractive index, composition, film density, and surface roughness depending on the deposition system.

• 한국광학회지
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• 제13권2호
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• pp.166-170
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• 2002

본 연구에서 우리는 반사형 LCD용 반사판을 최적화하고자 한다. 반사판의 새로운 표면구조를 체계적인 수식적 접근 및 분석을 통해 구한 후, 반사특성의 결과를 바탕으로 기존의 표면구조와 비교해서 보다 최적화된 표면구조를 제시하고자 한다. 반사특성의 결과로는 새로운 표면구조가 기존의 표면구조에 비해 동일한 시야각 범위에서 보다 균일한 반사율 분포를 나타내고 있으며, 또한 주변환경을 충분히 고려해서 사용자 위주의 자유로운 시야각 범위 조절이 가능함을 알 수 있다. 결과적으로, 새로운 표면구조는 보다 균일한 반사율 분포를 가지게 됨으로써, 기존의 반사형 LCD의 시야각 의존성을 상당부분 개선할 수 있으리라 본다.

• Journal of the Optical Society of Korea
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• 제20권1호
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• pp.199-203
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• 2016

An enzyme-free optical method is proposed for estimating high concentrations of glucose in a glucose-lactose mixture, based on a predictive equation that takes advantage of the reflective optical power observed at two discrete wavelengths. Compared to the conventional absorption spectroscopy method based on Beer's Law, which is mainly valid for concentrations below hundreds of mg/dL, the proposed scheme, which relies on reflection signals, can be applied to measure higher glucose concentrations, of even several g/dL in a glucose-lactose mixture. Two probe wavelengths of 1160 and 1300 nm were selected to provide a linear relationship between the reflective power and pure glucose/lactose concentration, where the relevant linear coefficients were derived to complete the predictive equation. Glucose concentrations from 2 to 7 g/dL in a glucose-lactose mixture were efficiently estimated, using the established predictive equation based on monitored reflective powers. The standard error of prediction was 1.17 g/dL.

• 한국지구과학회지
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• 제30권3호
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• pp.366-380
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• 2009

본 연구는 수업의 3가지 맥락(자료, 과제, 역할)에서 학습자의 특성과 그룹의 상호작용에 따른 그룹과 개인의 반성적 탐구는 어떤 차이가 있는지를 알아보고 이를 통해 효율적인 반성적 탐구활동을 위한 소그룹 구성과 교사의 지도에 시사점을 얻고자 하였다. 이를 위해 고등학교 1학년 1개 학급을 선정해서 반성적 탐구활동수업을 실시하고 수업을 녹화 전사해서 언어행동분석틀과 수업상황의 3가지 맥락으로 분석하였다. 본 연구의 결과로부터 학생개인과 그룹의 반성적 탐구는 학생들의 개별특성 그 자체보다는 다튼 학생과 학급에서 어떤 관계를 가지느냐에 더 영향을 받는다는 것을 알 수 있었다.

• 한국해안해양공학회지
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• 제19권5호
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• pp.429-435
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• 2007

비선형 Boussinesq 파랑전파 모델에서 방파제, 호안 등의 반사 경계면에 스펀지층을 설치하여 반사율을 모의하는 방법을 제안하였다. 스펀지층의 반사특성을 도출하기 위하여 상대 스펀지폭(스펀지층 폭/입사파장)을 변화시키는 일차원 수치실험을 수행하였다. 실험결과, 상대 스펀지폭을 조정함으로써 무반사에서 완전반사까지 반사율을 효과적으로 구현할 수 있음을 보였으며, 실험결과에 근거하여 반사율과 관련 무차원 변수들간의 다중회귀분석식을 제시하였다. 마지막으로, 본 스펀지층을 이차원 방파제에 적용하였으며, 스펀지층이 반사경계로서 평면 이차원 조건에서도 충분히 효과적으로 사용될 수 있음을 예시하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.614-615
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• 2009

For the high reflectance under the ambient light condition, a highly efficient diffractive reflector has been proposed, based on a micro grating structure.[1] This reflector was designed to show highly concentrated distribution of the reflected light to the normal direction of the reflector under specific incident conditions of the light. In order to apply a diffractive reflector to a reflective liquid crystal display, the coupling between the viewing angle characteristics of a liquid crystal (LC) cell and the reflective distribution of the reflector should be considered. Under the optimum configuration confirmed through the analysis of the coupling between a LC cell and a reflector, a reflective vertical alignment (VA) cell with a diffractive reflector shows contrast ratio and brightness much higher than that with a conventional bumpy reflector.

• 한국과학교육학회지
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• 제32권9호
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• pp.1405-1416
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• 2012

This study aims to analyze how pre-service science teachers' reflective thinking is presented during the microteaching process. The subjects of this study were 13 students who attended a lecture course on science teaching methods offered by the Department of Science Education of the College of Education at a national university. The simulated lessons that were performed during the microteaching process went through peer assessment and self-assessment. Then, the next set of lessons was conducted based on the assessment results. After the first set of simulated lessons, the pre-service teachers' reflection at the routine and technical levels was most remarkable in the focus dimension. In the inquiry and change dimensions, technical reflection stood out. Dialogic or transformative reflection was rarely presented. In addition, most of the pre-service teachers displayed mingling patterns of reflection levels in all of the three dimensions. The results of this study, in particular, prove that microteaching has a high level of applicability in terms of reflective thinking and instructional technology. Accordingly, there is a need for subsequent studies to create a new model that can encourage pre-service teachers' reflective thinking by structuralizing peer and self-assessment during the process of microteaching.

• 한국수학교육학회지시리즈A:수학교육
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• 제53권1호
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• pp.1-24
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• 2014

This study examines the effects of reflective journal writing on the mathematics self-efficacy in reciprocal peer tutoring. Participants were 38 high school students in Gyeonggi province who attended at a summer intensive mathematics course for 4 weeks. This study used a mixed method. SPSS 21.0 program was used to analyze the quantitative data, and the interviews, observational journals and reflective journals of 6 students were used to analyze qualitative data. According to the results, all the subcategories of mathematics self-efficacy, - mathematics problem-efficacy, mathematics success-efficacy, mathematics learning-efficacy, and mathematics subject-efficacy - improved except mathematics occupation-efficacy. In case of mathematics success-efficacy and mathematics problem-efficacy, students revealed the greatest improvement. In conclusion, reflective journal writing in reciprocal peer tutoring could be suggested as a treatment program to improve students' mathematics self-efficacy.

• 한국태양에너지학회 논문집
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• 제31권2호
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• pp.53-62
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• 2011

Heliostat in the tower type solar thermal power plant is a sun tracking mirror system to reflect the solar energy to the receiver and the optical performance of it affects to the efficiency of whole power plant most significantly. Thus a proper design of structure of the heliostat reflective surface could be the most important step in the construction of such power plant. The work presented here is a design of structure of optical surface of heliostat, which will be used in 200kW solar thermal power plant. The receiver located at 43(m) high from ground in tower has $2{\times}2$(m) rectangular shape. We first developed the software tool to simulate the energy concentration characteristics of heliostat using the ray tracing technique. Then, the shape of heliostat reflective surface is designed with the consideration of heliostat's energy concentration characteristics, production cost and productivity. The designed heliostat's reflective surface has a structure formed by canting four of $1{\times}1$(m) rectangular flat plate mirror facet and the center of each mirror facet is located on the spherical surface, where the spherical surface is formulated by the mirror facet mounting frame.