• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.877-880
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• 2001

This paper presents the new linear motion device so called "inch-worm" which gets large displacement by incrementally summing small displacements of PZT actuators. Dynamics stiffness of inch-worm is generally low compared to its driving condition due to the requirement of inch-worm like small size and light weight. This low stiffness may degenerate the positional precision of inch-worm. An inch-worm is realized using three PZT actuators, a monolithic moving device and a guide way frame. Driving input signal is shaped to reduce the residual vibration of inch-worm by LQG controller and cycloid step input. The practical feasibility of inch-worm is also examined by running test.ning test.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2010년도 춘계 학술논문 발표대회 1부
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• pp.33-36
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• 2010

The attention in construction Automation is getting higher since it could be the answer to the lack of skilled labor by decrease in construction population and aging which adversely affects productivity and quality in the construction site. We are on the way to develop a construction automation system adequate for domestic circumstances in Korea; it is called RCA(Robotic-crane based Construction Automation)system. Climbing hydraulic robots system is a part of RCA system and makes Construction factory(CF) climb through the guide rail on the core wall. The safety of climbing hydraulic robots system is at issue due to the overloaded weight of CF. Preventing this issue, present study did the design verification through the structural analysis and the simulation. Mock-up test also was done to analyze the drive performance of climbing hydraulic robots system.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.511-516
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• 2007

Rubber wheeled AGT(Automated Guide-way Transit) system is a prominence transportation system for urban area, because of its low construction cost and management, low noise and vibration and fine exterior view. AGT system uses concrete tracks. Concrete can be easily damaged by the impact, change of temperature and external loads. The fault of concrete track is harmful not only to riding quality but also to bridge. Therefore, in this study, the effects of railway prominence to the bridge are surveyed by experimental method. The experiment was executed for PSC bridge at AGT test line in Kyungsan. And the test results for 5mm, 10mm prominence and without prominence are compared and investigated, according to the vehicle speed.

• 한국과학교육학회지
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• 제25권1호
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• pp.26-40
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• 2005

Based on the Vygotskian perspective that a learner's thinking is constituted in his or her talk and the assumption that student talk in the classroom may occur in more than one way, this study examined discursive practices of students in Korean high school science classrooms. Data came from $11^{th}$ grade earth science classrooms where the Group Investigation (GI) method was implemented. Data source included verbatim transcripts developed from video recordings of class sessions in which students presented their science projects to the whole class and exchanged questions and answers during the presentations. The analysis of the videotape transcripts revealed five different modes of student talk, including 1) retrieving information, 2) reformulating information, 3) building on one's own experience, 4) elaborating current understanding, and 5) negotiating meanings with others. Considering that each of the five modes had different value for learning science, it was recommended that the teacher should engage students in more active modes of discourse and guide them into more sophisticated understanding of science.

• Asian Pacific Journal of Cancer Prevention
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• 제14권2호
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• pp.1159-1163
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• 2013

International meetings on various aspects of cancer- its etiology, its diagnosis, its treatment, its palliation, and its prevention and control are held frequently. Many have similar themes, and many seek and receive the same speakers and audiences. A fundamental question arises: what difference does any individual meeting/congress/conference make or add to our understanding of the relevant issues? While many meetings conduct evaluations at the end of the Congress, few use evaluation as a tool to guide design, implementation, and evaluation of both short and long term impacts, and address the question of "what difference did the Congress make". The International Cancer Control Congresses, which are held biennially in different regions of the world, took the opportunity to use evaluation in this way, and ask the relevant questions. This paper describes that evaluation session of the ICCC4, held in Seoul, Korea in November 2011, which was part of the larger evaluation issue.

• 한국항공운항학회지
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• 제28권4호
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• pp.102-116
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• 2020

The existence of appropriate teaching materials in foreign language is very essential especially if it is related to safety. Among them, the importance of textbooks is more emphasized because there is no suitable education or curriculum for EPTA (English proficiency test of aviation). A good textbook not only presents the right direction to study but also provides an efficient way to learn. This research exploded how well textbooks for EPTA are organized and analyzed current pilots' responses whether the textbooks are suitable for preparing EPTA through the questionnaire. The conclusion drawn is that textbooks for EPTA should be designed to encourage current and pre-pilots to learn how to communicate with controllers efficiently and briefly, and also should provide proper guide lines for preparing EPTA.

• Asia Marketing Journal
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• 제19권2호
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• pp.45-61
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• 2017

Incidental envy is known to motivate self-improvement behavior. This phenomenon occurs in part because feelings of inferiority guide subsequent behavior in a way to self-improve, after experiencing envy. However, no research has yet examined whether this tendency may be affected by social context: private versus public. Although extant literature suggests that envy generally leads to self-improvement, we demonstrate that this effect may be mitigated under public social contexts. Across two studies, we find that although incidental envy generally increases self-improvement behavior (e.g., effort exertion and charitable giving) in private social contexts, this tendency is attenuated under public social contexts. We conclude with a discussion of theoretical and practical implications of this finding.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 가을 학술논문 발표대회
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• pp.96-97
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• 2021

In the Building Act, performance-based fire safety design is being promoted for institutionalization. The behavior of the structure against fire conditions can be predicted by using the advanced numerical analysis method based on the FEM (Finite Element Method) to predict the entire structural behavior including the behavior of the structure, but there is a limit to expressing the fire properties of the space and predicting the fire properties It is difficult to determine the variables to be transmitted to the FEM (Finite Element Method) model from the fire simulation results using FDS (Fire Dynamics Simulator). Accordingly, the purpose of this study is to introduce the code user's manual for FDS and FEM unidirectional coupling analysis.

• 대한조선학회논문집
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• 제50권6호
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• pp.365-372
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• 2013

In this study, the flow characteristics and structural safety of a 500W class vertical-axis wind turbines(VAWT) for a fishing boat are investigated by numerical simulations. Guide vanes to increase the performance of the VAWT are investigated. And the best guide vane in the numerical simulations is applied to the VAWT. Also, modal analyses are performed to find out the natural frequencies of the VAWT, and the resonance safety of the VAWT is evaluated. The structural analysis of the VAWT is carried out by one-way FSI(Fluid Structure Interaction). And the results are used for the evaluation of structural safety according to IEC 61400-1 code. Finally, the possibility of the installation of the VAWT on the wheelhouse of a 9.77ton class fishing boat is checked. The results of the present research could be used as one of the fundamental data to design a VAWT for a fishing boat.

• 한국광학회지
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• 제28권6호
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• pp.314-326
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• 2017

현대생활에 매우 밀접하게 연관되어 있는 디스플레이는 IT산업이 발전함에 따라 단순한 표시장치에서 개인과 기기, 더 나아가 또 다른 개인을 연결해주는 네트워크의 창으로서 발전하고 있다. 이와 같은 디스플레이의 가장 중요한 구성요소인 백라이트유닛이 보다 얇고 더 밝으며 전기 소모량도 적게 구현하기 위해서 LED 광원을 적용하였으며, 휘도와 휘도 균일도 및 시야각을 향상 시키기 위한 복합 도광판에 대한 연구가 시작되었다. 본 논문에서는 최근 10여 년간 LED 백라이트 유닛의 괄목할만한 성장을 가능하게 한, 도광판의 산란패턴 형성에 관한 연구와 광원의 배치 및 구성 기술에 관하여 정리하고, 더 나아가 이러한 도광판 기술을 최근 주목을 받고 있는 LED 조명기구 설계에 적용시킨 대면적 flat-type 조명시스템에 대해 개괄적으로 기술한다. 최종적으로 현 기술을 보다 발전적으로 향상시킬 수 있는 방안 및 적용 방법에 관하여 논의한다.