• 한국광학회지
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• 제7권2호
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• pp.136-141
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• 1996

본 논문에서는 두 개의 비선형 박막으로 둘러싸인 평면 광도파로에서의 TE 비선형 도파광 특성에 대한 새로운 접근 방법을 제안한다. 비선형 박막에 대한 특성을 묘사하는 비선형 특성행렬을 이용하여 비선형 광도파로에 대한 비선형 분산 방정식을 해석적 형태로 유도한다. 분산 방정식을 기반으로 하는 전산시늉으로 도파광의 파워에 대한 모드 굴절율 변화, 전장의 세기가 최대인 위치, 그리고 파워 분포 등의 도파광의 비선형 특성을 계산한다. 자기-집속형 광도파로 구조에서 비선형 박막의 두께를 감소하면 파워-의존 비선형 모드 굴절율의 광학적 쌍안정 특성이 나타나며 광학적 쌍안정 특성을 위한 임계 파워는 증가한다. 그리고 비선형 광도파로 구조 내부의 파워분포 특성은 비선형 Fabry-Perot etalon의 동작 특성과 유사한 광학적 쌍안정 특성을 나타낸다.

• 공학교육연구
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• 제23권3호
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• pp.20-31
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• 2020

The purpose of this study is to suggest a meaningful way of implementing science and engineering integrated lessons in school science settings. To this end, two types of science and engineering integrated lesson units (focusing on the physic concepts of light and wave) were developed based on the core elements of science and engineering integrated lesson; object, context, engineering design, and connection with science. These two units were implemented in free semester program in a middle school in a metropolitan city. Throughout the process of program implementation, instructor's reflection and focus group interview with participant students were collected to reveal problems arising from the field implementation. In addition, engineering education experts were interviewed to discuss the potential problems and possible solutions for the problems. As results of the study, five main problems of implementing escience and engineering integrated lessons in a school science setting were revealed and practical solutions for the problems were suggested by the experts.

• 대한기계학회논문집B
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• 제20권6호
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• pp.2046-2056
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• 1996

The constrained melting inside an isothermally heated horizontal cylinder has been repeatedly investigated in many studies only for the moderate Rayleigh numbers. This study extends the range of Rayleigh numbers to systematically investigate the transition during melting processes, especially focusing on the complex multi-cellular flow pattern and thermal instability. The enthalpy-porosity formulation, with appropriate source terms to account for the phase change, is employed. For low Rayleigh numbers, initially developed single-cell base flow keeps the flow stable. For moderate Rayleigh numbers, even small disturbances in balance between thermal buoyance force and viscous force result in branched flow structure. For high Rayleight numbers, Benard type convection is found to develop within a narrow gap between thee wall and the unmelted solid. The marginal Rayleigh number and the corresponding wave number are in excellent agreement with those from linear stability theory.

• Journal of the Optical Society of Korea
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• 제18권1호
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• pp.60-64
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• 2014

We report the generation of 3.3-mW single-cycle terahertz (THz) pulses at 1-kHz repetition rate via optical rectification in MgO-doped prism-cut stoichiometric LiNbO3. Efficient pulse-front tilting of 800-nm pulses was realized by an optimized single-lens focusing scheme for radially-symmetric propagation of THz beams. In this geometry, nearly-diffraction-limited THz Gaussian beams with electric field strength as high as 350 kV/cm were generated. The pump-to-THz energy conversion efficiency of $1.36{\times}10^{-3}$ and the extremely high signal-to-noise ratio of ~1:15000 achieved are among the best results for 1-kHz single-cycle terahertz pulse generation ever demonstrated in room temperature operation.

• IUGG한국위원회:학술대회논문집
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• IUGG한국위원회 2003년도 정기총회 및 학술발표회
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• pp.18-18
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• 2003

Three-dimensional finite-difference simulation of earthquake ground motion is performed using a locally variable time-step (LVTS) scheme matching with discontinuous grids. Discontinuous grids in three directions and extension of the discontinuous grids' boundary to the free-surface in the LVTS scheme minimize the cost of both the computational memory and the CPU time for models like the localized sedimentary basin. A simplified model of sedimentary basin is dealt to show the feasibility and efficiency of the LVTS scheme. The basin parameters are examined to understand the main characteristics on ground-motion response in the basin. The results show that the seismic energy is concentrated on a marginal area of the basin far from the source. This focusing effect is mainly due to the constructive interference of the direct S-wave with the basin-edge induced surface waves. The ground-motion amplification over the deepest part of the basin is relatively lower than that above the shallow basin edge. Therefore the ground-motion amplification may be more related to the source azimuth or the direction of the incident waves into the basin rather than the depth of it.

• 한국의상디자인학회지
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• 제16권4호
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• pp.37-47
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• 2014

Recently, the Korean wave has caused many foreign nations to pay attention to various fields including Korean culture, arts, fashion and beauty. Korean images so far were mainly discussed in terms of aesthetics, and there is lack of efforts to visually shape Korean images. On the contrary, Oriental images focused around Japan and China have greater global influence and better globalized fashion styles compared to Korea. Therefore, it is necessary to suggest a globalized proposal of Korean fashion styling which reflects original and unique aesthetic characteristics of Korea that can be accepted by the global market. In this study, the concept and types of fashion styling and stylists were examined, as well as the definition of Korean image and types and characteristics of Korean images shown on fashion magazines. Also, after collecting photographs having Korean images that were included in the editorial fashion styling of Vogue Korea, their characteristics were analyzed. The results of interviews with professional fashion stylists were summarized to propose an editorial fashion styling with Korean image for overseas consumers who long for and wish to imitate Korean fashion styling.

• Human Ecology Research
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• 제56권5호
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• pp.461-472
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• 2018

Using a sample of third grade middle school students from the forth wave of Children and Youth Panel Survey in 2012, the mediation effects of private educational expenditure between parenting styles and children's academic performance were investigated by applying factor, cluster, tobit, and two stage regression analysis. The major results were as follows. First, four types of parenting style were identified. The most frequent parenting style was ambivalent parenting (tiger parenting) which was followed by authoritative parenting. Second, compared to permissive parenting style, ambivalent, authoritative, and authoritarian parenting styles were significantly associated with more private educational expenditures. Third, more private educational expenditures were significantly associated with higher academic performance of children. I found both a full mediation effect of private educational expenditure for ambivalent and authoritarian parenting styles, and a partial mediation effect for authoritative parents. Authoritative parenting style has a negative moderating effect on the relationship between household income and private educational expenditure, along with a positive direct effect on the academic performance of children. The results suggested that an authoritative parenting style was related with higher academic performance of children with less private educational expenditures compared to other parenting styles. The results also implied that the public policies to enhance authoritative parenting style among parents would be effective to reduce household's private educational expenditures.

• 한국실내디자인학회논문집
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• 제21권5호
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• pp.57-64
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• 2012

The ideologie of modern society as per something to phenomenology problem is to show various different looks. The community space is spring from Greek and Roman of community place by agora and forum is make a active communicate to interpersonally. Subject to centrically In the context, this paper is study on the Sustainable development for community space about interactive space. and focusing is Response to human of interact in each other intelligent space. And this paper suggestion is composition method of community space in technology advanced, Interactive interface form for human, sustainable to community space direction elements. First, I'll rearrange the distinctive features of modern society through references of various scholars. This is to understand how interactivity affects the whole society and what is the importance of this interactive wave. Second, I'll analyze several trends of modern community space and figure the change of methodology of design based on the advancement of design technology. This is to understand the interactive relation of the subjects. Third, I'll seek how community space design has changed in modern society and under which process design is made. This is to clarify the fact that the portion of interaction will increase in future design according to the intervention of equipment, which is one of the objects of interaction space.

• Progress in Superconductivity
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• 제14권1호
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• pp.11-16
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• 2012

본 연구에서는 자체일관적인 DFT+DMFT 계산을 통해 철의 3d 전자의 상관관계가 LiFeAs와 NaFeAs의 전자구조와 페르미 면 겹싸기 등에 미치는 영향을 알아보았다. 이들은 모두 철계 초전도체의 초전도성 형성에 매우 중요한 역할을 가지고 있다. DFT+DMFT 계산에서 얻어진 LiFeAs의 스펙트럼은, DFT에서 얻어진 띠 구조에 비해 매우 약한 페르미 면 겹싸기 현상을 보이며, NaFeAs 의 경우 DMFT 에서도 페르미 면 겹싸기 현상이 어느 정도 남아있는 것을 확인하였다. 그리고 이는 실험에서 보고된 ARPES 결과와 일치함을 확인했다.

• Safety and Health at Work
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• 제6권4호
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• pp.338-344
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• 2015

Background: The present study aims to investigate job stressors and stress relievers for Korean emotional laborers, specifically focusing on the effects of work conditions and emotional labor properties. Emotional laborers are asked to hide or distort their real emotions in their interaction with clients. They are exposed to high levels of stress in the emotional labor process, which leads to serious mental health risks including burnout, depression, and even suicide impulse. Exploring job stressors and relieving factors would be the first step in seeking alternatives to protect emotional laborers from those mental health risks. Methods: Using the third wave data of Korean Working Conditions Survey, logistic regression analysis was conducted for two purposes: to examine the relations of emotional labor and stress, and to find out job stressors and relievers for emotional laborers. Results: The chances of stress arousal are 3.5 times higher for emotional laborers; emotional laborers experience double risk-burden for stress arousal. In addition to general job stressors, emotional laborers need to bear burdens related to emotional labor properties. The effect of social support at the workplace is not significant for stress relief, unlike common assumptions, whereas subjective satisfaction (wage satisfaction and work-life balance) is proven to have relieving effects on emotional laborers' job stress. Conclusion: From the results, the importance of a balanced understanding of emotional labor for establishing effective policies for emotional laborer protection is stressed.