• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.400-401
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• 2012

그래핀(Graphene)은 열 전도도가 높고 전자 이동도(200 000 cm2V-1s-1)가 우수한 전기적 특성을 가지고 있어 전계 효과 트랜지스터(Field effect transistor; FET), 유기 전자 소자(Organic electronic device)와 광전자 소자(Optoelectronic device) 같은 반도체 소자에 응용 가능하다. 그러나 에너지 밴드 갭이 없기 때문에 소자의 전기적 특성이 제한되는 단점이 있다. 최근에는 아크 방출(Arc discharge method), 화학적 기상 증착법(Chemical vapor deposition; CVD), 이온-조사법(Ion-irradiation) 등을 이용한 이종원자(Hetero atom)도핑과 화학적 처리를 이용한 기능화(Functionalization) 등의 방법으로 그래핀을 도핑 후 에너지 밴드 갭을 형성시키는 연구 결과들이 보고된 바 있다. 그러나 이러한 방법들은 표면이 균일하지 않고, 그래핀에 많은 결함들이 발생한다는 단점이 있다. 이러한 단점을 극복하기 위해 자가조립 단층막(Self-assembled monolayers; SAMs)을 이용하여 이산화규소(Silicon oxide; SiO2) 기판을 기능화한 후 그 위에 그래핀을 전사하면 그래핀의 일함수를 쉽게 조절하여 소자의 전기적 특성을 최적화할 수 있다. SAMs는 그래핀과 SiO2 사이에 부착된 매우 얇고 안정적인 층으로 사용된 물질의 특성에 따라 운반자 농도나 도핑 유형, 디락 점(Dirac point)으로부터의 페르미 에너지 준위(Fermi energy level)를 조절할 수 있다[1-3]. 본 연구에서는 SAMs한 기판을 이용하여 그래핀의 도핑 효과를 확인하였다. CVD를 이용하여 균일한 그래핀을 합성하였고, 기판을 3-Aminopropyltriethoxysilane (APTES)와 Borane-Ammonia(Borazane)을 이용하여 각각 아민 기(Amine group; -NH2)와 보론 나이트라이드(Boron Nitride; BN)로 기능화한 후, 그 위에 합성한 그래핀을 전사하였다. 기판 위에 NH2와 BN이 SAMs 형태로 존재하는 것을 접촉각 측정(Contact angle measurement)을 통해 확인하였고, 그 결과 NH2와 BN에 의해 그래핀에 도핑 효과가 나타난 것을 라만 분광법(Raman spectroscopy)과 X-선 광전자 분광법(X-ray photoelectron spectroscopy: XPS)을 이용하여 확인하였다. 본 연구 결과는 안정적이면서 패턴이 가능하기 때문에 그래핀을 기반으로 하는 반도체 소자에 적용 가능할 것이라 예상된다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.11
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• pp.443-452
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• 2016

Six preservice teachers who participated in the "2016 service of summer vacation daycare programs by university and college students" focused on the programs for the formation of art, music and physical education and recreation culture were selected as research participants. The meaning of the experience they had through the service process was qualitatively analyzed. The subjects accepted the purpose of the self-directed service in which they should themselves solve a series of the entire process, from planning a volunteer program through drawing up the budget and purchasing materials to practice, evaluation and expressed the intention of participation. A volunteer program was conducted including visiting a daycare program for lower graders of elementary school (1st and 2nd grades) with more than 40 class hours during vacation. As research materials, research participants' journals, transcripts of individual interviews and group interviews, transcripts of phone calls, e-mail messages, and self-evaluation records of each class hour were collected. To increase the reliability and validity of the study, triangulation, member check, advice and review of the experts were conducted. In the study results, the volunteering experience-related significance for the preservice teachers who participated in the self-directed service were broadly categorized into 'Becoming a capable professional teacher', that consists of 'Increasing the power of thinking', 'Realizing the importance of communication', 'Doing together itself is important' and 'Ability to apply information and resources is needed'. 'Increase the continuity between preschool and elementary education' was subdivided into 'Get to know the necessity of the continuity between preschool and elementary education' and 'Want to learn the continuity between preschool and elementary education.'

• Korean Journal of Applied Biomechanics
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• v.19 no.1
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• pp.127-138
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• 2009

The purpose of this study was to investigate range of motion (ROM) and muscle activities according to the skills of Surya Namaskara in Vinyasa Yoga. Six females (skilled 2, unskilled 4) of university students participated in this experiment. The research factors were ROM and muscle activities for static poses on Surya Namaskara in Vinyasa Yoga. The six infrared cameras (Oqus 300, Qualisys Inc, Sweden) and Zero Wire EMG (Aurion, Italy) were used to acquire raw data, and the Qualisys Track Manager and Noraxon (MyoResearch XP Master Edition, USA) were used to process data. The %MVIC and ROM were analyzed with Visual 3D (C-Motion Inc, USA) and Noraxon. In conclusion, ROM and %MVIC between two groups were remarkable different according to the static poses of Yoga, therefore instructors have to provide step-by-step information that was suitable to themselves (ROM and EMG of poses).

• Journal of The Korean Association For Science Education
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• v.29 no.4
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• pp.373-387
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• 2009

The purpose of the study was to investigate the roles of parents in science learning at the Everyday Science Classroom (ESC). Discourses of 20 parent-child dyads were analyzed to identify the roles of the parents and their significance. Data were also gathered through questionnaires that were made to survey the perception of parents and students of the Everyday Science Classroom (ESC) in Gwanak-gu. The results showed that parents played the role of Guide as well as Learner. Parents as the Guide showed roles of Process guide, Cognitive facilitator, Participation inducer, and Authoritative manager. Parents helped their children to accomplish the experiment successfully (34.5%) and offered cognitive scaffolds (21.3%) and affective scaffolds (8.7%) for children to reach a level of understanding that they could not reach by themselves. However, parents who helped their own children without considering their needs repressed children's autonomous learning (1.6%). The roles of parents as the Learner were categorized into Active learner (16.1%), Collaborative fellow learner (15.1%), and Authoritative leading learner (2.7%). The multiple roles of parents can influence the children's understanding of science in both positive and negative ways. This study can provide basic information on the roles of parents and their interaction with their children. Reflection on positive aspects of parent participation in program development will promote the understanding of science in both parents and children.

• Journal of Digital Convergence
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• v.10 no.10
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• pp.97-106
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• 2012

In the past, executive managers made a decision based on personal experience and knowledge due to lack of the appropriate and timely information. With the development of information systems and technologies, efficiency and productivity of business operation has been enhanced. In this study, we propose a system design and architecture blue-print related to strategic decision making support system. The proposed system consists of 3 key parts; individual business feasibility test, business portfolio feasibility test, business portfolio management. The three key parts are comprised of 11 components to generate information and knowledge based on various data input from inside and outside of firm. This system is expected to provide objective and reliable output to users. In addition, the proposed strategic decision support system would help respond to a rapidly changing business environment.

• Journal of the Korean Data and Information Science Society
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• v.26 no.4
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• pp.813-826
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• 2015

This research deals with an estimation method for kinetic reaction model. The kinetic reaction model is a model to explain spread or changing process based on interaction between species on the Biochemical area. This model can be applied to a model for disease spreading as well as a model for system Biology. In the search, we assumed that the spread of species is stochastic and we construct the reaction model based on stochastic movement. We utilized Gillespie algorithm in order to construct likelihood function. We introduced a Bayesian estimation method using Markov chain Monte Carlo methods that produces more stable results. We applied the Bayesian estimation method to the Lotka-Volterra model and gene transcription model and had more stable estimation results.

• Korean Journal of Childcare and Education
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• v.2 no.2
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• pp.165-185
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• 2006

The purposes of this study were (1) to investigate the relationship of conflict components, and (2) to investigate interaction of conflict participants. Subjects were ninety-four 3-, 4- and 5-year-olds recruited from eleven child care centers in Seoul, Kyonggi and Incheon province. Interaction process between these young children were recorded by a video camera, and the scenes were transcribed for analysis of peer conflict situations which occurred between two children. Statistical methods used for data analysis were frequencies, percentiles, means, standard deviations, Chi-square. First conflict components are interrelated. There was a significant difference conflict resolution strategies according to conflict issue, and a significant difference conflict outcomes according to conflict resolution strategies. Also conflict outcomes were related to conflict emotion expression. Second, the stratigies interaction of conflict participants were significant and conflict emotion expression of conflict participants were significant.

• Journal of the Korean Geographical Society
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• v.49 no.2
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• pp.178-199
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• 2014

Changwon Industrial Complex is commonly framed as the best example of strong initiative of the Korean developmental state. And this explanation has been given in the theoretical frame of 'neo-Weberian accounts' i.e., strongly 'national-territorial' and state-centric terms of the predominant. I argue that a geopolitical economy approach focusing on the historical background of the development of Changwon Industrial Complex will shed light on crucial sociospatial dimensions of the Korean developmental state's industrial complex success. I examine, in particular, the multi-scalar processes through which the changes of the industrial complex building plans for the promotion of machine industry in 1960's have been influenced by the complex and dynamic interactions among social actors acting at diverse geographical scales. I show that the formation of the industrial complex in Korea was more heavily influenced by the interactions, contestations, and collaborations among social actors, acting in and through the state, rather than by the state initiative.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.199-199
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• 2012

최근 그래핀의 대면적 합성 및 롤투롤 전사 공정의 개발로 그래핀의 상용화가 가시화 되고 있다. 하지만, 그래핀의 독특한 특성인 선형적이고 밴드갭이 없는 에너지 띠 분포 때문에 반도체 소자로서의 직접적인 적용에는 한계가 있다. 이러한 문제를 해결하기 위한 돌파구로써, 그래핀 복합체의 연구와 개발이 활발히 진행되고 있으며 본 연구에서는 그래핀 복합 적층 구조를 다룬다. 이는 디스플레이, 초고속 반도체 소자, 고성능 광전자소자 및 초고감도 센서 등 다양한 분야에 대한 그래핀의 실용화 가능성이 높아진 것을 의미한다. 특히, 높은 가시광 투과도와 낮은 면저항으로 기존 투명 전극에 대표적으로 사용되고 있는 ITO (Indium Tin Oxide)를 그래핀으로 대체하는 것에 관한 연구가 활발히 진행되고 있다. 하지만 그래핀이 높은 전자이동도를 가지는 것에 비하여 비저항과 투과도 측면에 있어서는 ITO의 성능을 뛰어넘지 못하는 실정이다. 따라서 본 연구에서는 ITO가 가지는 취약점인 기판과의 약한 접착력, 높은 취성, 기판과의 열팽창률 차이 등의 공정상 문제점을 극복하고자 하였다. 그래핀 복합 적층 필름은 플라스틱 기판 (PET) 위에 열 화학기상증착법(Chemical Vapor Deposition, CVD)을 이용하여 합성한 그래핀을 전사하고, ITO 용액을 도포한 다음 다시 그래핀을 씌워 제작하여 샌드위치 구조(sandwich structure)를 형성하였다. 완성된 필름은 광학적, 전기적 특성 분석을 수행하였다. 광학적 분석으로는 라만 분광을 이용한 그래핀 품질평가와 파장대에 따른 광 투과도, 그리고 반사도 측정을 하였으며, 전기적 특성은 면저항을 측정함으로써 분석한다. 결함이 적고, 대면적에 걸쳐 한 층을 이루어야 하는 고품질 그래핀의 요구사항에 따라 라만 분광의 G, 2D, D 띠를 분석하였다. G와 2D 띠의 비율을 통해 그래핀의 층 수를, D 띠의 강도를 통해 결함의 유무를 판단하였다. 또한, 가시광 영역에서 90% 이상의 광 투과도를 보여야 하는 투명 소자의 요구사항 달성 정도를 UV-VIS를 이용하여 확인하였다. 마지막으로, 제작한 필름의 면저항 또한 4-프로브 멀티미터를 이용하여 측정하고, 일반적인 터치스크린의 면저항인 $500{\Omega}/sq$를 만족하는지 평가하였다.

• Journal of the Korean Chemical Society
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• v.57 no.6
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• pp.778-788
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• 2013

The purpose of this study was to examine the change of the beginning science teachers' perception change through the mentoring program. Participants in this study were four mento-teachers, one university professor, two teachers in doctor, two teacher in doctor's or master's course, and four mentee-teachers who had less than three years teaching experience. We performed five times one to one mentoring for a year. We collected data such as video recordings of mentee-teacher's classes, lesson plans, recording of one to one mentoring and transcription, mento and mentee journals, preliminary-interim-post interview and transcription, and RTOP class observation report. Based on the result of this study, five times mentoring over a year changed mentee-teacher's perception and their teaching practice.