• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.813-819
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• 2006

The state of the art for the design of swing ann actuators for optical disc drives is to obtain the high efficient dynamic characteristics, especially for the small size for the mobile information devices, It is affected by the need of consumers who wants the portable digital storage devices maintaining highly functional and removable characteristics of the optical disk drive (ODD). As a necessary consequence, the need of the small form factor (SFF) storage device has been considered as an important part in the information storage technology. In this paper. we suggest a new conceptual miniaturized swing arm type actuator that has high efficient dynamic characteristics as well as satisfies the sensitivity and the heat emission requirements for the SFF-ODD. It also uses a tracking electromagnetic (EM) circuit for a focusing motion. Due to the size constraint, the thermal problem of optical head arises; therefore, we design an efficiently heat emitted structure for the actuator.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.115-118
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• 2002

The purpose of this paper is to design a pick-up for the small form factor optical disk drive and to fabricate a micro-compensatory lens for the pick-up using the micro-compression molding process. At design stage, the optical elements including the objective lens and the compensatory lens are miniaturized. The height of pick-up and free working distance are designed as 2mm and 0.2% respectively. To analyze the fabricated micro-compensatory lens, the system was analyzed using the surface profile of the fabricated micro-compensatory lens and CODE V which is commercial software. The RMS wave front aberration of the system using fabricated micro-compensatory lens is 0.01677λ which is lower than Marechal's criterion, 0.07λ.

• Electronics and Telecommunications Trends
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• v.30 no.1
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• pp.65-76
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• 2015

스마트폰의 보급에 따른 대용량 멀디미디어 서비스의 폭발적인 수요 증가에 따라데이터센터의 100Gb/s 광트랜시버에 대한 수요는 2017년을 기점으로 10Gb/s를 추월하여 2018년 데이터콤 전체 시장의 50% 이상을 차지할 전망이다. 한편, 데이터센터의 소비전력 및 시스템 집적도 증가를 위해 광트랜시버의 Form-factor는 CFP(40G/100G Form-factor Pluggable)에서 QSFP28($4{\times}28G$ Quad Small Form-factor Pluggable)로 약 1/14배 소형화될 전망이며, 이에 따른 광트랜시버 구성 부품의 집적도는 높아지고 소비전력은 현재 대비 1/9로 낮아져야 한다. 본고에서는 소형화 및 저전력화를 위한 광트랜시버의 표준화 및 기술동향과 국내외 시장동향에 대해 기술한다.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.11 no.6
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• pp.709-715
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• 1999

To optimize a heating and cooling system, we need an exact solution lot radiant heat transfer in any form of room or building. This paper describes the solution method of view factor by the area weighted average and graphical method to calculate the radiant heat exchange or daylighting level in any form of room or building. This study shows that the area weighted average and graphical methods have many points of merits(calculation speed, correctness and calculation capability in an arbitrary form of room shapes etc.) compared with existing methods

• Journal of the Korean Institute of Landscape Architecture
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• v.20 no.3
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• pp.33-43
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• 1992

The perceptual characteristic on the slope scenery around highway is very similar as the general perceptual characteristic in the landscape. This process determines by the relationship between the scenery observers and the characteristics of its place. It is very important to have a analysis on highway slope scenery in our particular culture in Korea since our country's highways are done by cutting mountains : therefore, we have a lot of slopes around highways. The physical characteristics on the highway scenery determines how we should build scenery around highway to a satisfactory level. The results drawn from this research work are as follow: 1) The satisfaction for slope scene had been affected by sex, native and experience of travel. I thought that the slope scene having peculiar form will offer the highest satisfaction. 2) Psychological factor, reflected satisfaction of slope scene, 몽 a grip of three factors as the factor of evaluation, texture, formation, and presumption formula is : Satisfaction=1.04(Evauluation factor)+0.83(Texture factor)+0.15(Formation factor)+4.28)R2=0.69). 3) Vine among the vegetation componeents of slope scene highly correlated with the evaluation factor and grass, shrub correlated with the texture factor. 4) Rock among the structual components of slope scene highly correlated with the formation factor, and stockade, lattice correlated with the evalution factor. 5) Gradient among the properties which determined slope form, highly correlated with the formation factor.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.2
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• pp.277-284
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• 1993

Interfacial surface crack perpendicular to the surface, which is imbedded into bonded quarter planes under single anti-plane shear load is analyzed. The problem is formulated using Mellin transform, form which single Wiener-Hopf equation is derived. By solving the equation stress intensity factor is obtained in closed form. This solution can be used as a Green's function to generate the solutions of other problems with the same geometry but of different loading conditions.

• The Korean Journal of Food And Nutrition
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• v.20 no.4
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• pp.384-391
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• 2007

The purpose of this study was to investigate the preference determinants of buddhist temple food(BTF) and leaded to its activation based on these results. 354 subjects were participated in the survey using questionnaires. 66.9% of subjects had over the normal interest. The taste of BTF was light(34.7%) and it would be helpful in their health(72.9%), subjects answered. Lightness and not strong taste was the main reason of preferring BTF(50.8%), but lack of nutrients was dislike reason of BTF generally. According to factor analysis, the factors of preference determinants deduced as the external form, social environment, health, essential quality and information of food. There were not significantly different between factors by sex and family form. External form, health and essential quality of food had the significant difference by generation and education level. The factors of external form and the essential quality of food showed the significant difference by job. According to the monthly income, the factor of social environment, health and information of food had the significant difference.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.1
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• pp.195-211
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• 2015

Flat plate friction lines have been used in the process to estimate speed performance of full-scale ships in model tests. The results of the previous studies showed considerable differences in determining form factors depending on changes in plate friction lines and Reynolds numbers. These differences had a great influence on estimation of speed performance of full-scale ships. This study was conducted in two parts. In the first part, the scale effect of the form factor depending on change in the Reynolds number was studied based on CFD, in connection with three kinds of friction resistance curves: the ITTC-1957, the curve proposed by Grigson (1993; 1996), and the curve developed by Katsui et al. (2005). In the second part, change in the form factor by three kinds of friction resistance curves was investtigated based on model tests, and then the brake power and the revolution that were finally determined by expansion processes of full-scale ships. When three kinds of friction resistance curves were applied to each kind of ships, these were investigated: differences between resistance and self-propulsion components induced in the expansion processes of full-scale ships, correlation of effects between these components, and tendency of each kind of ships. Finally, what friction resistance curve was well consistent with results of test operation was examined per each kind of ships.

• BMB Reports
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• v.29 no.6
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• pp.530-534
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• 1996

Astrocyte are the major glial cell type in the central nervous system (CNS), and analogous to macrophage, mediates the number of immune responses such as production of cytokines including tumor necrosis factor alpha ($TNF-{\alpha}$) upon activation. $TNF-{\alpha}$ has been implicated in neuroimmunological disorders through killing oligodendrocytes and thus causing demyelination. It has been previously demonstrated that mitogen-activated T cells synthesized a 26 kDa precursor form of $TNF-{\alpha}$ which is bound to the surface of a membrane, and is later secreted as a 17 kDa mature version. In order to examine whether astrocytes would produce the transmembrane form of $TNF-{\alpha}$, astrocytes were stimulated with biological stimuli and the membrane form of $TNF-{\alpha}$ was analyzed by Western blot and FACS analysis. When astrocytes are stimulated with lipopolysaccharide (LPS), $IFN-{\gamma}/LPS$, or $IFN-{\gamma}/IL-1{\beta}$, they were able to express a membrane-anchored $TNF-{\alpha}$ of approximately 26 kDa protein which was immunoreactive to an $anti-TNF-{\alpha}$ antibody, whereas unstimulated astrocytes or astrocytes treated with $IFN-{\gamma}$ or $IL-1{\beta}$ alone was not. Our FACS data were also consistent with the immunoblot analysis. Our result suggests that the membrane form of $TNF-{\alpha}$ expressed by activated astrocytes may cause local damage to oligodendrocytes by direct cell-cell contact and contribute to demyelination observed in multiple sclerosis (MS) and experimental allergic encephalomyelitis (EAE).

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2000.04a
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• pp.248-252
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• 2000

Form-ratio means the ratio of height/Width/Depth in 3-dimensions. The golden ratio or golden section is included as one of the form-ratio. We conducted two kinds of kansei experiments of cubic model and refrigerator varied from 1:1:1 to 1:1:3.66 on the scale of x:y:z. The subjects evaluate the form-ratios of 3-dimensional cubes and virtual products with SD-scale Kansei words(feelings and images). We applied the factor analysis to identify semantic space in cube model and virtual products. Finally, we compared with kansei structure of cube model and virtual product.