• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1215-1219
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• 2003

Light Guide Panel(LGP) is a key part of backlight unit(BLU) which transforms line-light of lamp to surface-light. Dot pattern is formed on the injected LGP surface by screen printing. This dot pattern is composed of several ten thousands micro dots of diameter 150-180$\mu\textrm{m}$ or so. The dot patterning by screen printing causes low productivity and low performance of TFT-LCD. This research develops the micromachining technology for LGP mould which could form micro dot pattern by injection molding, removing the existing screen printing process.

• 반도체디스플레이기술학회지
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• 제5권3호
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• pp.37-41
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• 2006

In this paper, a composition modulation of Dot-matrix display grayscale is presented. There's two method of expression of Dot-matrix Display grayscale. One is PWM by controlling pulse width. The other is PAM by controlling pulse amplitude. Composition modulation of Dot-matrix use PWM and PAM together. Composition modulation shows the number of grayscale as number of grayscale of PWM$\times$number of grayscale of PAM and have the effect of reduced size than existing single modulation.

• Applied Science and Convergence Technology
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• 제25권6호
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• pp.154-157
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• 2016

The energy dispersion and magnetization of a modified magnetic dot are investigated numerically. The effects of additional electrostatic potential, magnetic field non-uniformity, and Zeeman spin splitting are studied. The modified magnetic quantum dot is a magnetically formed quantum structure that has different magnetic fields inside and outside of the dot. The additional electrostatic potential prohibits the ground-state angular momentum transition in the energy dispersion as a function of the magnetic field inside the dot, and provides oscillation of the magnetization as a function of the chemical potential energy. The magnetic field non-uniformity broadens the shape of the magnetization. The Zeeman spin splitting produces additional peaks on the magnetization.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2011년도 추계학술발표대회
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• pp.1166-1169
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• 2011

In this paper, we design a Circle dot Code, In our scheme, we design a dot patterns for increasing maximum capacity and also for increasing robustness to Affine Transformation. Our code Can be extended according number of data circle. We use three data circle vision code. In this type code, after acquiring camera images for the Circle dot Codes, and perform error correction decoding using four position symbols and six CRC symbols. We perform graph based dot code analysis which determines the topological distance between dot pixels. Our code can be bridged the real world and ubiquitous computing environment.

• 한국안광학회지
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• 제17권4호
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• pp.435-440
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• 2012

목적: 본 연구는 $2{\times}$ 배율을 가지는 도트사이트 장치의 개발에 관한 것이다. 방법: 무배율 도트사이트로 먼 거리를 주시할 때 목표물을 확대해서 볼 수 있도록 하기 위해 기존 무배율 도트사이트에 착탈식으로 장착할 수 있는 새로운 광학계를 개발한다. 이는 기존 무배율($1{\times}$) 도트사이트를 $2{\times}$ 배율 도트사이트로의 전환을 필요에 따라 쉽게 할 수 있도록 하기위한 것이다. 결과: 배율이 없는 도트사이트에 착탈할 수 있는, doublet 렌즈가 쌍으로 구성되는, $2{\times}$ 배율 어포칼 광학계를 설계 제작하였다. 이를 사용하였을 때 우리는 외부 목표점을 2배 확대하여 조준할 수 있어서 조준의 정확성을 더욱 높일 수 있었다. 결론: 배율이 없는 일반 도트사이트에 착탈할 수 있는 $2{\times}$ 배율 어포칼 광학계를 설계 제작할 수 있었다. 이것에 의해 외부 목표점을 2배 확대하여 조준할 수 있도록 함으로서 조준의 정확성을 더욱 높일 수 있게 되었다.

• 한국생활과학회지
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• 제16권2호
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• pp.407-419
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• 2007

The purpose of this study was to identify the effect of four clothing cues dot pattern size and ground field of color area ratio on dress's wearer image. The experimental materials developed for this study are a set of stimuli and response scales(The 7-point semantic). The stimuli were 30 color pictures manipulated with the combination of dot pattern size, dot pattern on background of color area ratio and neutral dress's using computer simulation. The subjects were 180 female undergraduates living students in Gyeong-nam. The result of this study are as follows: Image factor of the stimulus was composed of 5 different components (visibility, gracefulness, attractiveness, cuteness, womanly). Especially, Neutral color combination independently influenced the every components. In regarding the effect of interaction between each variable, the combination of dot pattern on background of color area ratio, dot pattern size on the combination had cuteness, womanly.

• Journal of the Optical Society of Korea
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• 제19권3호
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• pp.272-276
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• 2015

The PbS quantum dot is an emerging photovoltaic material, which may provide high efficiency breakthroughs. The most crucial element for the high efficiency solar cells's development is to understand charge transport characteristics of PbS quantum dot solids, which are also important in planning strategic research. We have investigated charge transport characteristics of PbS quantum dot solids thin films using space charge limited conduction analysis and assessed thickness dependent photovoltaic performances. The extracted carrier drift mobility was $low-10^{-2}cm^2/Vs$ with the estimated diffusion length about 50 nm. These and recently reported values were compared with those from a commercial photovoltaic material, and we present an essential element in further development of PbS quantum dot solids materials.

• Current Optics and Photonics
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• 제3권2호
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• pp.143-149
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• 2019

Shape ellipticity dependence of the exciton fine energy levels in CdTe and CdSe nanocrystal quantum dots were compared theoretically by considering the crystal structure and the Coulomb interaction of an electron and a hole. While quantum dot ellipticity changes from an oblate to prolate quantum dot via spherical shape, both the fine energy levels and the dipole moment in wurtzite structure of a CdSe quantum dot change linearly for ellipticity. In contrast, CdTe quantum dots were found to show a level crossing between the bright and dark exciton states with a significant change of the dipole moment due to the cubic structure. Shape ellipticity dependence of the optical nonlinearities in CdTe and CdSe nanocrystal quantum dots was also calculated by using semiconductor Bloch equations. For a spherical shape quantum dot, only $1^L$ dominates the optical nonlinearities in a CdSe quantum dot, but both $1^U$ and $0^U$ contribute in a CdTe quantum dot. As excitation pulse area becomes strong (${\sim}{\pi}$), the optical nonlinearities of both CdSe and CdTe quantum dots are mainly governed by absorption saturation. However, in the case of a prolate CdTe quantum dot, the real part of the nonlinear refractive index becomes relatively significant.

• Bulletin of the Korean Chemical Society
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• 제7권4호
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• pp.257-262
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• 1986

Thixotropy is a time-dependent shear-thinning phenomenon. We derived a new thixotropic formula which is based on the generalized viscosity formula of Ree and Eyring, $f={\Sigma}\frac{X_i}{{\alpha}_i}sinh^{-1}$ () (Refer to the text concerning the notation.) The following is postulated: (1) thixotropy occurs when small flow units attached to a large flow unit separate from the latter under stress (2) elastic energy(${\omega}$) is stored on the large flow unit during the flow process, and (3) the stored energy contributes to decrease the activation energy for flow. A new thixotropic formula was derived by using these postulations, $f={\frac}{X_0{\beta}_0}{\alpha_0}{\dot{s}}+{\frac}{X_1{\beta}_1}{{\alpha}_1}{\dot{s}}+{\frac}{X_2}{{\alpha_x}}sinh^{-1}$[$({\beta}_0)_2$ exp $(-C_2{\dot{s}}^2/RT){\cdot}{\dot{s}}$] f is the shear stress, and s is the rate of shear. In case of concentrated solutions where the Newtonian flow units have little contribution to the viscosity of the system, the above equation becomes, $f=\frac{X_2}{\alpha_2}sinh^{-1}$[$({\beta}_0)_2$ exp $(-C_2{\dot{s}}^2/RT){\cdot}{\dot{s}}$]. In order to confirm these formulas, we applied to TiO2(anatase and rutile)-water, printing ink and mayonnaise systems. Good agreements between the experiment and theory were observed.

• 디지털융복합연구
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• 제11권3호
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• pp.371-380
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• 2013

본 연구는 남자 비만 중학생을 대상으로 최대하 방법의 PACER 검사를 통해 최대산소섭취량($\dot{V}O_{2max}$)을 추정할 수 있는 추정식을 개발하고자 중학교 남자 비만 학생 57명을 대상으로 Bruce 프로토콜의 최대운동부하검사와 PACER 검사를 실시하였다. 최대하 수준을 결정하기 위해 PACER 운동 중 목표심박수(75%$HR_{max}$ 이상)가 나타나는 왕복횟수 구간별 대사반응을 측정하였으며, $%HR_{max}$ 구간별(75%, 80%, 85%, 90%, 95%) 대사반응 지표를 단계적 선택법으로 회귀분석을 실시하였다. 그 결과 다음의 모형이 산출되었다. 모형 1(90%$HR_{max}$의 모형): $\dot{V}O_{2max}$(ml/kg/min) = 142.721-0.275(왕복횟수)-0.48(심박수)+0.177(체중)-1.536(연령)[표준오차 3.90ml/kg/min; 2단계까지 운동진행]. 모형 2(95%$HR_{max}$의 모형): $\dot{V}O_{2max}$(ml/kg/min) = 182.851-0.103(왕복횟수)-0.744(심박수)+0.186(체중)-0.324(연령)[표준오차 4.51ml/kg/min; 3단계까지 운동진행]. 모형 1의 추정된 $\dot{V}O_{2max}$와 실측 $\dot{V}O_{2max}$간 차이 평균은 $3.25{\pm}6.32ml/kg/min$(%error=6.84%), 모형 2는 $3.16{\pm}4.54ml/kg/min$(%error=5.75%). 비만인 대상자들에게 최대하 운동방법으로는 심박수와 운동지속시간이 짧았던 모형 1이 모형 2보다 적합한 형태로 생각된다.