• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.199-199
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• 2013

최근 단파장 광전 소자와 고출력 고주파 전자 소자에 대한 수요 때문에 넓은 밴드갭 에너지를 갖는 반도체에 관심이 많다. 이중에서, ZnO는 우수한 화학 및 역학적 안정성, 수소 플라즈마 내구성과 저가 제조의 장점 때문에 광전자 소자 개발 분야에 적합한 산화물 투명 전극으로 관심을 끌고 있다. 불순물이 도핑되지 않은 ZnO는 본질적으로 산소 빈자리 (vacancy)와 아연 격자틈새 (interstitial)와 같은 자체의 결함으로 말미암아 n형의 극성을 갖기 때문에, 반도체 소자로 응용하기 위해서는 도핑 운반자의 농도와 전도성을 제어하는 것이 필요하다. 본 연구에서는 박막 제조시 제어성, 안정성과 용이하게 성장이 가능한 졸겔 (sol-gel) 방법을 사용하여 사파이어와 석영 기판 위에 Cu가 도핑된 ZnO 박막을 성장시켰으며, 그것의 구조, 표면 형상, 평균 투과율, 광학 밴드갭 에너지를 계산하였다. 특히, Cu의 몰 비를 0, 0.01, 0.03, 0.05, 0.07, 0.1 mol로 변화시키면서 ZnO:Cu 박막을 성장시켰다. ZnO:Cu 졸은 zinc acetate dihydrate, 2-methoxyethanol (용매), momoethanolamine (MEA, 안정제)을 사용하여 제조하였다. 상온에서 2-methoxyethanol과 MEA가 혼합된 용액에 zinc acetate dihydrate (Zn)을 용해시켰다. 이때 MEA와 Zn의 몰 비는 1로 유지하였다. 이 용액을 $60^{\circ}C$ 가열판 (hot plate)에서 24 h 동안 자석으로 휘젓으며 혼합하여 맑고 균일한 용액을 얻었다. 이 용액을 3000 rpm 속도로 회전하는 스핀 코터기의 상부에 장착된 사파이어와 석영 기판 위에 주사기 (syringe)를 사용하여 한 방울 떨어뜨려 30 s 동안 스핀한 다음에, 용매를 증발시키고 유기물 찌꺼기를 제거하기 위하여 $300^{\circ}C$에서 10분 동안 건조시킨다. 기판 위에 코팅하는 작업에서 부터 건조 작업까지를 10회 반복한 다음에, 1 h 동안 전기로에 장입하여 석영 기판 위에 증착된 시료는 $550^{\circ}C$에서, 사파이어 기판은 $700^{\circ}C$에서 열처리를 수행하였다. Cu의 몰 비 0, 0.01, 0.03, 0.05, 0.07, 1로 성장된 ZnO:Cu 박막에 대한 x선 회절 분석의 결과에 의하면, 모든 ZnO:Cu 박막의 경우에 관측된 34.3o의 피크는 ZnO (002) 면에서 발생된 회절 패턴을 나타낸다. 이것은 JCPDS #80-0075에 제시된 회절상과 일치하였으며, ZnO:Cu 박막이 기판에 수직인 c-축을 따라 우선 배향됨을 나타낸다. 사파이어 기판 위에 증착된 박막의 경우에, Cu의 몰 비가 점점 증가함에 따라(002)면 회절 피크의 세기는 전반적으로 증가하여 0.07 mol에서 최대를 나타내었으나, 석영 기판 위에 증착된 박막의 경우에는 0.05 mol에서 최대를 보였다. 외선-가시광 분광계를 사용하여 서로 다른 Cu의 몰 비로 성장된 ZnO:Cu 박막에서 광학 흡수율 (absorbance) 스펙트럼을 측정하였으며, 이 데이터를 사용하여 평균 투과율을 계산한 결과, 투과율은 Cu의 몰 비에 따라 현저한 차이를 나타내었다. Cu의 몰 비가 0.07 mol일 때 평균 투과율은 80%로 가장 높았으며, 0.03 mol에서는 30%로 최소이었다. 광학밴드갭 에너지는 Tauc 모델을 사용하여 계산하였고, 결정 입자의 형상과 크기와의 상관 관계를 조사하였다.

• Journal for History of Mathematics
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• v.18 no.4
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• pp.85-100
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• 2005

In recent papers (Pak et al., Pak and Kim), it was suggested to positively use the history of mathematics for the education of mathematics and discussed the determining problem of the order of instruction in mathematics. There are three kinds of order of instruction - historical order, theoretical organization, lecturing organization. Lecturing organization order is a combination of historical order and theoretical organization order. It basically depends on his or her own value of education of each teacher. The present paper considers a concrete problem determining the order of instruction for the concept of angle. Since the concept of angle is defined in relation to figures, we have to solve the determining problem of the order of instruction for the concept of figure. In order to do this, we first investigate a historical order of the concept of figure by reviewing it in the history of mathematics. And then we introduce a theoretical organization order of the concept of figure. From these basic data we establish a lecturing organization order of the concept of figure from the viewpoint of problem-solving. According to this order we finally develop the concept of angle and a related global property which leads to the so-called Gauss-Bonnet theorem.

• Journal of Korean Classical Literature and Education
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• no.35
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• pp.5-46
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• 2017

This study aims to investigate the context of materials in literature textbooks and the awareness about the educational value of classical literature, as part of an interest in literature education phenomena. This study accepts the premise that textbooks affect the practice of classical literature education and, in particular, materials in textbooks are chosen according to the intentions, demands, and perspectives of education in specific social conditions. I divided the educational value of classical literature into two categories, classical and literary value, and investigated the actual conditions and context of materials of literature textbooks based on the 2009 revised curriculum and the 2011 revised curriculum. Classical literature is generally alienated and excluded; contemporary literature materials are mostly included and organized in the domains of 'the role of literature', 'reception and production of literature' and 'literature and life.' In addition, the tendency to heighten classical value and diminish literary value is deepening. In order to solve the problem that classical literature is only included as the product of the past, changes must be made not just to the curriculum, which are external changes, but to the awareness of the essence of classical literature, which are internal changes. Above all, generality as 'literature' and the sense of distance about space and time as 'classic' should be connected to various relationships which respond to problematic situations and the demands of learners. Based on the relationships, we can expect a rich diversity of contexts and aspects of included classical literature. In addition, an extension of the width and scope of included classical literature is anticipated. The reduction of workload, the advent of the concept of capability and the dissolution of traditional literature concepts are the changes of external environment, which is continuously requiring renewed investigation into classical literature beyond simple appropriateness.

• Journal of Korean Philosophical Society
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• v.144
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• pp.371-398
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• 2017

The emotions that Aristotle treats in Rhetoric II 2-11 are broadly divided into two groups: the one is the so-called basic emotions, the other the emotions that are opposed to them. The reason that he draws attention to the opposite emotions is that, for example, angry judges must be placed in an opposite state. The question is whether the calmness treated in Rhetoric II 3 is an emotion. Because it is treated in the Ethics as a virtue and thus as a trait of character. How is calmness distinguished as an emotion from that as a virtue? And in what way is it opposed to anger? In short, what is the calmness, inasmuch as it is an emotion? This is the question which is the task of this work. The thesis asserted in this paper is that calmness is the disposition to do a service for another that results from praise or some other act that enhances a belief in one's worth. To substantiate the thesis, the following questions are discussed. The first question is whether the calmness could also contain proportions of pleasure and pain. The question also arises whether it could be also treated properly according to the standard 'target person-intentional object-mental state'. Finally, there is a comparison between the concept of calmness in the Ethics and Rhetoric, so that the latter concept places itself in the foreground.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.993-999
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• 2008

A girder height limitation is the critical parameter for rapid construction of bridge deck and construction space limitation especially in urban area such as high population area and high density habitats. A standard post-tensioned I-shaped concrete girder usually demands relatively higher girder height in order to retain sufficient moment arm between compression force and tensile force. To elaborate this issue, a small U-shaped section with wide flanges can be used as a possible replacement of I-shaped standard girder. This prestressed concrete box girder allows more flexible girder height adjustment rather than standard I-shaped post-tensioned girder plus additional torsion resistance benefits of closed section. A 30m-long, 1.7m-high and 3.63m-wide actual small prestressed concrete box girder is designed and a laboratory test for its static behaviors by applying 6,200kN amount of load in the form of 4-point bending test was performed. The load-deflection curve and crack patterns at different loading stage are recorded. In addition, to extracting the dynamic characteristics such as natural frequency and damping ratio of this girder, several excitation tests with artificial mechanical exciter with un-symmetric mass are carried out using operational frequency sweep-up. Nonlinear finite element analysis of this 4 point bending test under monotonic static load is investigated and discussed with aids of concrete damaged plasticity formulation using ABAQUS program.

• The Journal of the Korea Contents Association
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• v.21 no.7
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• pp.59-70
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• 2021

This paper studies and analyzes the effect of illustrations in picture books on time representation with fictional picture books as the study scope. In this paper, the time type of picture books can be divided into time point, timeline and time rhythm, referring to case analysis from time symbolic elements, picture layout and picture sequence respectively. First of all, time symbolic elements are referred to the time point and time rhythm. The materialized time symbolic element is things that can directly represent time and trigger associations with time; the color symbolic element means the color changes in the real world within a certain time; the contrast of light and shadow corresponds to the changes in a day. Fast-moving objects will be presented with dashed or blurred lines, while static, stable and slow objects will be depicted with solid lines. Secondly, the picture layout of illustrations in picture books is suitable for representing the content of the timeline and describing the sequence or causality of events. Finally, the picture sequence can represent the timeline, time rhythm and "synchronicity". It will make use of visual logic to win readers' trust in time information expressed in pictures, and then follow and connect viewpoints on the basis of adapting to reading habits. The essence of time representation in picture books is to express time by space, and use different combinations of elements in space and visual guidance to convey time information.

• Cross-Cultural Studies
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• v.47
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• pp.163-190
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• 2017

This paper studies the recent surge in the number of faith-based films in Hollywood, with the aim to explore the context and implications of this new trend. By using the theoretical framework of the study of the Tilich and Van der Leeuw, who have explored the relationship between religion, culture and art, this article discusses the meaning of the spiritual theme in the film. A couple of common points can be found among the faith-based films that have been produced since the 2010s. While these films attempt a universal approach to the fundamental theme of spirituality through popular narratives familiar to the audience, they also stress 'historical truthfulness and credibility' by representing the reality, such as a featuring real person or a true story in the film. The main characters are depicted as "victorious losers" that are distinguished from the typical Hollywood superhero and the films repeatedly show the human being constantly 'asking' questions to God. By analyzing these characteristics, the paper demonstrates that recent Hollywood faith-based films have successfully differentiated themselves from existing religious films while symbolizing the universal beliefs and values beyond the religious message so as to attract more audiences to this field. The paper also suggests that despite the advances in modern science and knowledge, the public will always yearn for a spiritual recovery and salvation through the film medium, serving as a potential source that provides an outlet for spiritual experience.

• Cross-Cultural Studies
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• v.50
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• pp.173-196
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• 2018

This study, which works to develop a method of focusing on A Quiet Dream by Zhang Lu, explored the structural differences of films and the changes in Zhang Lu's aim and perspective as noted in films, by a review to grasp his internal changes in texts and contextual factors. In A Quiet Dream, Zhang Lu made a filmic attempt that had never been made in the world of films prior to that date. He tried an aesthetic experiment on how films could reorganize the world, by using the effect of obscuring the boundary between reality and dream in films and generating a new narrative regarding filmic reality, actual reality, and the life and artistic truth of the Diaspora. Generally speaking, the changes in the narrative in A Quiet Dream seem to be his resistance against himself and the Diaspora. Thus, in the discussion about A Quiet Dream, relying on the external factors intervening in the relationship between the subject of creation and films is not a useful endeavor at this time. Consequently, it is noted that after settling down in Korea, Zhang Lu could directly approach the changes in the cultural position of films in multilayered ways, where films were the most dynamic part of his life. Due to the changes in the Diaspora, he could obscure the boundary for the first time in the world of films and experiment with how films could escape develop an interesting perspective that deviated from reality, and made a new goal to show new ideas regarding the individual's awareness of the world.

• Journal of the Korean earth science society
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• v.39 no.6
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• pp.617-629
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• 2018

The purpose of this study was to explore the elementary school teachers' perceptions about making a model of volcanic activity. Thirty elementary teachers participated in the study after they in which they conducted the experiment of "Making a Model of Volcanic activity". A questionnaire was used to investigate how the teachers understood the strengths and weaknesses of the experiment in terms of the goals of school science inquiry. The results showed that 50-60% of the teachers were able to conduct the experiment as guided in the textbook regardless of their career or area of concentration. The teachers perceived that the experiment of current textbook was safe and useful for students to develop their creativity. However, they pointed out three major weaknesses of the textbook experiment: First, the textbook experiment does not clearly present the main purpose of the activity. Second, it does not appropriately reflect the natural volcanic activity. Third, it is a merely simple craft activity. In addition, the teachers agreed that the main goals of school science inquiry are the application of scientific knowledge, development of inquiry skills and cultivation of student's curiosity. However, the teachers perceived that the experiment of current textbook did not meet these three goals. They suggest that the experiment reflect the nature of real volcanic activities.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.5
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• pp.47-55
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• 2019

The army of republic of korea have been continued to transform their logistics support system structure for better efficient logistics support system in preparation for the future environment. Logistics system has supply network structure which is connected by various units and supply network structure received attention as a factor of success of supply network. Many researchers have continuously researched inventory management, transportation or economy factors for supply network, but such a study on the one in military supply network structure analysis is still slower than the study of analysis of other factors until now. In this study, we identify military supply network structure influence factor by application of social network analysis method which is used broadly and analyze co-relationships between supply network structure influence factor and valued APL(average path length) as a criteria of efficiency of military supply network. By this study it has value of military supply network influence factor identification for the better military supply network fabrication.