• Journal of Information Display
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• 제4권2호
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• pp.7-12
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• 2003

We discuss main techniques to improve legibility of electroluminescent displays. Emphasis is placed on use of destructive optical interference to cancel ambient light reflected from the back electrode of the device. Basic optical principles and material composition of the optical interference contrast-enhancing stack (CES) are presented. We also describe the improved human factors of electroluminescent devices assisted with a CES. Achromatic contrast is the most important contributor to display's legibility. In some conditions color contrast may also be important. Contributing to both luminance and color contrast enhancement, the contrast-enhancing stack may play an important role in various display applications.

• 디지털융복합연구
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• 제12권1호
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• pp.127-139
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• 2014

본 연구의 목적은 스마트폰 운영체제의 지배적 디자인을 결정하는 주요 요인이 무엇인지 제시하고 제시된 요인들과 사용만족 간의 논리적 인과관계를 검증하는데 있다. 이를 위해 지배적 디자인을 결정하는 스마트폰 운영체제의 주요 결정요인을 OS호환성, OS향상성, 사용자기반, 그리고 네트워크 효과 등으로 제시했다. 그리고 사용만족과의 논리적 인과관계를 실증분석했다. 연구결과, 스마트폰 운영체제의 OS호환성과 OS향상성은 사용기반 확대에 긍정적인 영향을 미치는 것으로 나타났다. 특히 OS향상성은 사용기반을 확대 시킬 뿐만 아니라 네트워크 효과를 강화시키는 원인으로 나타났다. 그리고 직접적으로 사용만족에도 긍정적인 영향을 미치는 것으로 나타났다. 연구결과는 그동안 실증연구가 이루어지지 않았던 운영체제의 지배적 디자인 결정과정에 대해 논리적 인과관계를 제시하여 학문적으로 뿐만 아니라 실무적으로도 크게 기여했다고 판단된다.

• 한국산학기술학회논문지
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• 제14권3호
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• pp.1081-1089
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• 2013

본 연구는 국내 녹색산업의 경쟁력 강화를 위한 클러스터 형성방안을 제시하고자, 녹색산업의 지역경쟁력과 영향요인을 분석했다. 첫째, 신재생에너지산업은 경기, 경남, 충북, 충남, 울산, 전남에서, 탄소저감산업은 울산, 경기, 경북, 충남, 서울, 충북, 인천에서 각각 경쟁력이 있는 것으로 나타났다. 둘째, 신재생에너지산업은 기업, 노동, 연구개발 등의 요소조건 부문이, 탄소저감산업은 성과, 정책 제도, 시장점유, 산업특화 등의 구조 및 경쟁 부문이 가장 중요한 요인으로 분석되었다. 셋째, 녹색산업은 기존의 산업기반이 양호한 지역에서 상대적으로 경쟁력이 있는 것으로 나타났다. 따라서 국내 녹색산업의 경쟁력 강화를 위해서는 기존 산업기반의 녹색화와 더불어 선택과 집중의 전략이 요구된다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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• pp.175-177
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• 2004

The current JPEG-2000 standard is a wavelet based scheme because wavelet transform have some advantages compare to DCT transform. In compressed images, there are some image degradation factors like contrast distortion by Quantization process. This factor is very important to HVS (Human Visual System). Therefore, In this paper, we propose a new algorithm for contrast enhancement using the properties of wavelet coefficients. This algorithm is processed in the wavelet domain and so it can be applied efficiently to JPEG-2000.

• Journal of Mechanical Science and Technology
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• 제14권9호
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• pp.997-1004
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• 2000

The experiments were conducted by using water and paraffin slurry to investigate the effect of a chip spacing in the multichip module on the cooling characteristics from an in-line $4{\times}3$ array of discrete heat sources which were flush mounted on the top wall of a channel. The experimental parameters were chip spacing in a multichip module, heat flux of simulated VLSI chip, mass fraction of paraffin slurry, and channel Reynolds number. The removable heat flux at the same chip surface temperature decreased as the chip spacing decreased at the first and fourth rows. The local heat transfer coefficients for the paraffin slurry were larger than those for water, and the chip spacing on the local heat transfer coefficients for paraffin slurry influenced less than that for water. The enhancement factor for paraffin slurry showed the largest value at a mass fraction of 5% regardless of the chip spacing, and the enhancement factors increased as the chip spacing decreased. This means that the paraffin slurry is more effective than water for cooling of the highly integrated multichip module.

• 한국방송∙미디어공학회:학술대회논문집
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• 한국방송공학회 2013년도 하계학술대회
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• pp.315-318
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• 2013

A novel foveation filter method is proposed in DCT domain. For countering the blocking and ringing artifacts, we devise the tools measuring the signal gradient, the block signal variations in the DCT domain. Each measurement is properly applied to each enhancement region and smoothing region. The proposed method optimally adapts the enhancement factors to the characteristics of the underlying signals and so maximizes the enhancement performances with significantly suppressing the artifacts. The subjective and objective evaluations verify that the proposed method sustains producing the improved video qualities for various sequences without tuning any parameters to individual sequences.

• 한국산업융합학회 논문집
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• 제4권4호
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• pp.395-401
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• 2001

The characteristics of heat transfer and pressure drop through tubes has been investigated experimentally for a compound heat transfer enhancement. The test tubes were spirally indented tubes with wire coil inserts which had a various combinations of pitch and helix angles. Pure water was used as working fluids for the experiments, Heat transfer coefficients and friction factors of the test tubes were evaluated from the values of measured temperatures, flow rates and pressure drops. An performance evaluation was performed to find an optimal combination of spirally indented tubes with wire coil inserts. When the helix angle of wire coil insert are $71^{\circ}-72^{\circ}$, the best heat transfer enhancement was shown. The friction factor was 9 - 13 times higher than those in smooth tubes, and the heat transfer was enhanced a maximum of 500%.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.67-67
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• 2011

Compound semiconductor/CNTs composites have shown considerably improved efficiency improvement in photovoltaic devices, which is often attributed to two different factors. One is the formation of efficient electronic energy cascade structures. The other effect of CNTs on the performance of photovoltaic devices is the decrement of interfacial resistance. The interfacial resistances at n-type/ p-type materials and/or n-type materials/TCO electrode are reduced by an outstanding electrical property of CNTs. In addition to the effects of CNTs, we report the third reason for increment of efficiency in photovoltaic devices by CNT's well-known electrical field enhancement effects. The improved ${\beta}$ values in reverse-FE currents of CIGS electrode with SWNTs layers indicate the enhancement of electrical field in photovoltaic devices, which implies the acceleration of the electron transfer rate in the cell. Due to the formation of an efficient electronic energy cascade structure and the decrease of the interfacial resistance as well as the improvement of the electrical field in the photovoltaic devices, the power conversion efficiency of electrochemically deposited superstrate-type CIGS solar cells was increased 24.3% in the presence of SWNTs and showed 10.40% conversion efficiency.

• 한국전자파학회논문지
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• 제17권7호
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• pp.648-658
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• 2006

본 논문에서는 하나의 유전체 층으로 이중 대역 지향성을 증가시킬 수 있는 박판 frequency selective surface (FSS) superstrate를 제안하고 이의 설계 방법을 소개하였다. 제안하는 박판 FSS superstrate는 동일한 주기의 두 FSS 어레이가 하나의 유전층 위 아래로 존재하고, 두 FSS 어레이의 위치에 offset 을 주어 이중 대역 지향성 향상을 위한 기존의 FSS superstrate가 가지는 문제점을 제거하였다. 단위 셀 시뮬레이션을 이용하여 다양한 파라미터의 변화에 따른 특성을 분석하고, 이를 이용하여 제안하는 superstrate의 설계 방법을 제시하였다. 3 가지 다른 quality factor를 가지는 단위 셀과 이를 이용한 복합 안테나의 특성을 비교하여 두 대역에서의 지향성 향상 정도를 유사하게 하는 단위 셀의 quality factor 값을 제시하였다. 이와 함께 효율적으로 지향성을 향상시킬 수 있는 최적의 FSS 어레이 크기를 제시하였다. 제안한 박판 FSS superstrate를 이용한 안테나 복합체를 제작하였으며, 측정된 결과는 시뮬레이션 된 결과와 매우 잘 일치한다.

• 지식경영연구
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• 제5권1호
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• pp.83-99
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• 2004

This research aims to verify individual and organizational factors that will affect knowledge sharing, especially in research & development organizations with a premise that knowledge sharing is one of the most important factors of successful knowledge management. Many factors which are supposed to affect knowledge sharing arc empirically investigated in this research : individual factors ((1)self esteem (2)expected contribution), organizational factors ((3)top management's will, (4)accessibility of knowledge management system (5)validity of evaluation & reward knowledge sharing, (6)trust, (7)open communication). As a result, it is found that 'expected contribution' among individual factors and 'open communication' and 'validity of evaluation & reward' among organizational factors are highly correlated with knowledge sharing. These findings suggest that enhancement of perceived expected contribution among employees and building cultures of open communication and effective evaluation & reward system for knowledge sharing will contribute to activation of knowledge sharing in the research and development organizations.