• 한국수학교육학회지시리즈A:수학교육
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• 제47권2호
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• pp.221-224
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• 2008

The article shows that the concept 'weight' and the concept 'heaviness' give rise to different abstractions in the sense of Piaget and that these two concepts are differentiated by set-theoretic devices. The failure of differentiation of these two concepts 'weight' and the 'heaviness' can cause the failure of learning of the difference between reflective abstraction and empirical reflective abstraction. To explain the Piagetian abstrcation in a classroom, the author suggests to use the concept 'color' instead of the concept 'weigtht'.

• 수산해양교육연구
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• 제26권2호
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• pp.401-420
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• 2014

This study aims to analyze middle school students' systemic thinking to express organic relations between different organ systems about the movement of food and air and teachers' reflective thinking about science teaching through their reflective journals after the lesson of digestion, circulation, respiration and excretion. Firstly, when investigating the moving route of hamburger eaten inside the body, students expressed the names, locations and forms of organs in the digestive system more than those in the circulatory system or the excretory system. When investigating the moving route of a painkiller taken inside the body, students seemed to have more difficulty in expressing the related organ systems than when investigating the moving route of other things, and they mostly drew pictures of organs in the digestive system as done for the moving route of hamburger. However, when investigating the moving route of water drunk inside the body, students mostly described organs in the digestive system but drew more pictures of organs in the excretory system, than when investigating the moving route of other things. When investigating the moving route of air inhaled inside the body, students mostly drew pictures of organs in the respiratory system, but the rate of their drawing pictures of circulatory organs was low. Secondly, this study analyzed one of the teachers' reflective journals, named Mr. Park. According to his journal, students showed different levels of understanding of organ names, depending on their degrees of familiarity with each organ, and in regard to the locations of organs, science teachers mostly aim to achieve learning objectives so much that they often forget to instruct the locations of organs in fact. As for the forms of organs, science teachers mostly spend so much time explaining the functions of organs that they often forget to describe the exact form of each organ.

• 한국초등과학교육학회지:초등과학교육
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• 제31권3호
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• pp.372-385
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• 2012

For decades, reflection has been recognised as a meaningful tool to bring forth teachers' ownership as well as knowledge and action empowerment in teacher education. Yet there have been few studies on elementary teachers' reflection on their science teaching in Korea. In this study, 71 reflective journals of 24 elementary teachers on their science teaching were analyzed. The characteristics of reflective journals were analyzed in terms of 'productive reflection', a concept suggested by Davis (2006). Unproductive reflection is mainly descriptive without analysis, whereas productive reflection can promote teachers' learning by integrating four aspects of teaching (learner/learning, subject matter knowledge, instruction and assessment). The result showed what elementary teachers consider and emphasize and how they integrate their ideas. Most of reflective journals included aspects of 'instruction', 'learner/learning', and 'subject matter knowledge'. However 'instruction' was emphasized most frequently (69.0%) than 'subject matter knowledge' (33.8%) and 'learner/learning' (26.8%). 'Assessment' was hardly included nor emphasized. More than half of the journals (56.3%) showed no integrations, which were unproductive reflection. A third of the journals (32.4%) integrated only two aspects among four. Average score of integrations was 1.6 on a scale of 4 points. The integrations were not affected by the length of reflective journals and the teaching experience. These findings suggest that productive reflection would not increase naturally with teaching experience and there needs more tactful guidance to develop elementary teachers' productive reflection on their science teaching.

• 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.

• 대한전기학회논문지
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• 제40권6호
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• pp.590-597
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• 1991

Ion reflective index and sheet resistance in the silicon oblique range smaller than 8 degree and optimization of annealing temperature have been studied. A four point probe was used to obtain the sheet resistance after annealing, while high resolution SIMS was used to determine the Boron and Fluorine atomic profiles before and after annealing. Experimental results and theory of ion reflective index are compared. Ion reflective index was found to decrease according to increasing an ion oblique angle. We introduce a simple analytical model ion reflection, concidering the Rutherford scattering model. This result can not be explained by the conventional Gaussian model.

• 한국환경교육학회지:환경교육
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• 제25권2호
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• pp.149-160
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• 2012

This study examined the effects of reflective writing activities utilizing environmental related mass media. Two classes participated as an experimental group (n=31) and a control group (n=30). Both groups of students learned five different topics on environment, such as diversity of ecosystem, global warming, desertification, reduction of the amount of carbon, and eco-friendly behavior. The experimental group students was taught utilizing mass media about each topic and had opportunities of reflective writing about each topic, while the control group of students was taught through lectures. The results indicated that students in the experimental group represented significantly better scores on environmental worldview, environmental sensitivity, and eco-friendly behavior compared to the control group students (p<.01).

• Current Optics and Photonics
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• 제4권4호
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• pp.353-360
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• 2020

Adopting an elaborately designed reflective objective consisting of four mirrors, we have developed a rotating-polarizer-type microspot spectroscopic ellipsometer (SE) with an ultra-small spot size. The diameter of the focused beam, whether evaluated using a direct-image method or a knife-edge method, is less than 8.4 ㎛. After proper correction for the polarizing effect of the mirrors in the reflective objective, we unambiguously determine the dispersion of the complex refractive index and the thickness of monolayer MoS₂ using the measured microspot-spectroellipsometric data. The measured ellipsometric spectra are sensitive enough to identify small variations in thickness of MoS₂ flakes, which ranged from 0.48 nm to 0.67 nm.

• 한국지역지리학회지
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• 제17권4호
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• pp.459-476
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• 2011

본 연구는 반성방법의 차이에 따른 예비 지리교사의 수업전문지식 변화를 파악하는 데 목적을 두고 있다. 연구 목적을 달성하기 위해 l차 모의수업 결과를 토대로 통일한 수준에 있는 데 명의 예비교사들을 선정한 후, 각각 상이한 반성을 거쳐 2차 모의수업을 실시하도록 하였다. 이 때 각각의 수업에 대한 동료평가를 실시함으로써 예비교사들의 수업전문지식 구비정도를 파악했고, 1차 및 2차 수업 간의 점수를 비교함으로써 반성방법의 차이에 따른 수업전문지식의 변화 양상을 파악했다. 연구 결과는 다음과 같다. 먼저, 1차와 2차 모의수업을 비교해본 결과 모든 예비교사의 평균점수가 상승했지만, 반성하지 않거나 자기반성을 행한 예비교사에 비해 전문가와의 협력적 반성을 행한 예비교사의 점수가 큰 폭으로 향상되었다. 다음으로 자기반성을 통해 반성적 성찰지를 작성한 예비교사의 경우 반성적 사고는 가능했지만 반성적 실천으로 이어지는 데에는 한계가 나타났다. 마지막으로 통계적으로 유의미한내용지식의 향상은 전문가와의 협력적 반성을 행한 예비교사에게만 나타났다. 특히 영역과 학습자에 대한 이해 영역에서 유의미한 통계 값이 나타났다. 이를 통해 내용이나 상황영역 부문은 예비교사 스스로의 자기반성 및 반복적 수업 실연을 통해서도 향상될 수 있지만, 영역과 학습자에 대한 이해 영역은 조력자의 도움이 필요하다는 사실을 도출할 수 있었다.

• 과학교육연구지
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• 제40권3호
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• pp.203-218
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• 2016

이 연구에서는 반성적 사고를 강조하는 실험보고서를 도입하여 이러한 실험보고서의 적용이 학습자의 메타인지능력과 탐구능력에 미치는 영향을 살펴보았다. 일반물리실험을 수강하는 대학교 1학년 학생을 대상으로 한 학기 동안 반성적 사고를 강조한 실험보고서 작성을 도입한 후 일반적인 실험보고서를 작성한 학생들과 메타인지능력과 탐구능력의 변화를 비교하고, 반성적 사고를 강조한 실험보고서를 사용한 학생들의 의견을 조사하였다. 반성적 사고를 강조한 실험보고서를 작성한 학생의 메타인지능력이 일반적인 실험보고서를 사용한 학생에 비해 유의미하게 상승하였으며, 이들의 탐구능력도 일반적인 실험보고서를 사용한 학생들과 마찬가지로 상승한 것으로 나타났다. 설문 결과, 설문 참여자들은 대체로 이러한 실험보고서가 복습과 메타인 지능력 및 탐구능력의 향상에 도움이 되며, 향후 교사가 되면 이 보고서 양식을 사용할 의향이 있다고 응답하였다.

• 대한수학교육학회지:수학교육학연구
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• 제9권2호
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• pp.383-404
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• 1999

This study began with an epistemological question about the nature of mathematical cognition in relation to the learner's activity. Therefore, by examining Piaget's 'reflective abstraction' theory which can be an answer to the question, we tried to get suggestions which can be given to the mathematical education in practice. 'Reflective abstraction' is formed through the coordination of the epistmmic subject's action while 'empirical abstraction' is formed by the characters of observable concrete object. The reason Piaget distinguished these two kinds of abstraction is that the foundation for the peculiar objectivity and inevitability can be taken from the coordination of the action which is shared by all the epistemic subjects. Moreover, because the mechanism of reflective abstraction, unlike empirical abstraction, does not construct a new operation by simply changing the result of the previous construction, but is forming re-construction which includes the structure previously constructed as a special case, the system which is developed by this mechanism is able to have reasonability constantly. The mechanism of the re-construction of the intellectual system through the reflective abstraction can be explained as continuous spiral alternance between the two complementary processes, 'reflechissement' and 'reflexion'; reflechissement is that the action moves to the higher level through the process of 'int riorisation' and 'thematisation'; reflexion is a process of 'equilibration'between the assimilation and the accomodation of the unbalance caused by the movement of the level. The operational learning principle of the theorists like Aebli who intended to embody Piaget's operational constructivism, attempts to explain the construction of the operation through 'internalization' of the action, but does not sufficiently emphasize the integration of the structure through the 'coordination' of the action and the ensuing discontinuous evolvement of learning level. Thus, based on the examination on the essential characteristic of the reflective abstraction and the mechanism, this study presents the principles of teaching and learning as following; $\circled1$ the principle of the operational interpretation of knowledge, $\circled2$ the principle of the structural interpretation of the operation, $\circled3$ the principle of int riorisation, $\circled4$ the principle of th matisation, $\circled5$ the principle of coordination, reflexion, and integration, $\circled6$ the principle of the discontinuous evolvement of learning level.