• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.598-600
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• 2002

To improve the luminance and efficiency of AC PDP, the effects of a square pulse applied to the address electrode during a sustain-period is investigated. Through this experiment, we confirmed the improvement of luminance and efficiency. We performed the temporal behavior measurement for the light emitted from AC PDP at floating state of the address electrode and at various auxiliary voltages (including ground state) applied to the address electrode using the scanned point detecting system. In the case of using an auxiliary voltage pulse, emission starts at the inner edges of the anode and cathode simultaneously. Also, we obtained the larger two discharge volumes compared with the normal sustain discharge where address electrode is floated.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.374-377
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• 2001

We have synthesized poly(3-hexylthiophene)(P3HT), which is the most famous conducting polymer and studied the optical properties of P3HT. And then fabricated the device using P3HT as an emitting layer. For the improve of hole injection from ITO electrode to P3HT emitting layer, we use transparent polyaniline(PANI) electrode. In the voltage-current-luminance characteristics of ITO/PANI/P3HT/LiF/Al device which use the PANI film synthesised during 5 cycle, the device turn on at the 2V and the luminance of $218nW/cm^{2}$ obtained at 12V. External quantum efficiency of ITO/PANI/P3HT/LiF/Al increased at 8V than that of ITO/P3HT/LiF/Al device.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.27-28
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• 2000

We examined ($He_x-Ne_{l-x}$)-Xe gas discharge in an AC PDP cell by computer simulation to understand the gas mixing effects. The breakdown and sustain voltage were significantly lowered with the addition of Ne into He-Xe. The luminance and efficiency in ($He_x-Ne_{l-x}$)-Xe also improved when compared with the He-Xe or Ne-Xe gas mixture. The luminance is maximum around $30{\sim}40%$ He addition, while the efficiency shows peak values at 70% He. Two-dimensional numerical simulation was done to explain these results.

• Transactions on Electrical and Electronic Materials
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• v.6 no.3
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• pp.91-96
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• 2005

We report the efficient red light-emitting diodes based on the fluorescent dye 4-(dicyanomethylene)-2-i-propyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTI) and 5,6,11,12-tetraphenyl naphthacene (rubrene) codoped in the tris(8-hydroxyquinoline)aluminum $(Alq_3)$. Luminance efficiency of 2.2 cd/A with a Commission International De L'Eclairage (CIE) chromaticity coordinate of x, y = (0.640, 0:350) are achieved at the driving current density of $20\;mA/cm^2$. Adding the rubrene to the DCJTI in tris(8-hydroxyquinoline)aluminum $(Alq_3)$, the red color purity and luminance efficiency improved comparing to the DCJTI only doped devices because the rubrene molecules assist the polarization effect of DCJTI by molecular interaction and enhance the energy transfer from $(Alq_3)$ to DCJTI.

• Journal of the Semiconductor & Display Technology
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• v.15 no.4
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• pp.79-85
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• 2016

For long life time and high efficiency, not necessary in improvement of LED chip structure, but also improve heat radiation for decrease heat in LED chip. In this study, efficiency decline factor has been investigated in LED lamp as study heat characteristic, luminance flux and heat resistance. When LED lamp temperature was increased, about 7% loss of luminance flux. In consequence of temperature analysis, width of fin was the most important factor of heat radiation. As a result, secure the enough heat path is very important factor of LED lamp design.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.791-793
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• 2009

We have developed novel small molecular materials for solution phosphorescent OLEDs having multilayered device structures. These novel materials are applied as an interlayer which is between a buffer layer (or hole injection layer) and an emitting layer to improve the luminance efficiency of solution green phosphorescent OLEDs. In order to form stable double layers by spincoating process, we take the advantage of solubility differences of interlayer materials and emitting materials. Using CIM3 as an interlayer, we have attained the best luminance efficiency, 36 cd/A at a given constant of 2000cd/$m^2$ in the structure of ITO/PEDOT:PSS/CIM3/CIM6:Ir(mppy)$_3$/BAlq/Alq$_3$/LiF/Al.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.374-377
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• 2001

We have synthesized poly(3-hexylthiophene)(P3HT), which is the most famous conducting polymer and studied the optical properties of P3HT. And then fabricated the device using P3HT as an emitting layer. For the improve of hole injection from ITO electrode to P3HT emitting layer, we use transparent polyaniline(PANI) electrode. In the voltage-current-luminance characteristics of ITO/PANI/P3HT/LiF/Al device which use the PANI film synthesised during 5 cycle, the device turn on at the 2V and the luminance of 218 nW/$\textrm{cm}^2$ obtained at 12V. External quantum efficiency of ITO/PANI/P3HT/LiF/Al increased at 8V than that of ITO/P3HT/LiF/Al device.

• Proceedings of the KIEE Conference
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• 2007.11a
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• pp.177-179
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• 2007

기존의 fence전극구조는 ITO구조에 비해 휘도가 감소하여 효율이 떨어지는 것으로 알려져 있다. 따라서 효율 상승을 위하여 다음과 같은 fence 구조를 제안하였다. 실험은 reference(II-fence형 전극구조)와 제안된 구조(II-fence형 돌기격벽측배치)로 구성되어있는 4-inch AC-PDP 패널을 직접 제작하여 discharge current, luminance, luminous efficiency를 측정하여 비교하였다. 제안된 구조의 휘도는 약 5% 감소하였으나, 방전전류가 최대 14% 감소하였고, 효율면에서 최대 12%의 효율 상승을 가진다.

• Journal of the Institute of Convergence Signal Processing
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• v.6 no.2
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• pp.74-81
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• 2005

As the multimedia data increases, various scene change detection algorithms for video indexing and sequence matching have been proposed to efficiently manage and utilize digital media. In this paper, we propose a robust scene change detection algorithm for video sequences with abrupt luminance variations. To improve the accuracy and to reduce the computational complexity of video indexing with abrupt luminance variations, the proposed algorithm utilizes edge features as well as color features, which yields a remarkably better performance than conventional algorithms. In the proposed algorithm first we extract the candidate shot boundaries using color histograms and then determine using edge matching and luminance compensation if they are shot boundaries or luminance changes. If the scene contains trivial brightness variations, the edge matching and luminance compensation are performed only for shot boundaries. In experimental results, the proposed method gives remarkably a high performance and efficiency than the conventional methods with the similar computational complexity.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.41 no.5
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• pp.35-44
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• 2004

With increase in digitalmedia data, various video indexing and video sequence matching algorithms have been proposed to efficiently manage and utilize digital media. In this paper, we propose a robust video indexing algorithm to detect scene changes for video sequences with abrupt luminance variations and an efficient video sequence matching algorithm for video sequence query. To improve the accuracy and to reduce the computational complexity for video indexing with abrupt luminance variations, the proposed algorithm utilizes edge features as well as color features, which yields a remarkably better performance than conventional algorithms. In the proposed algorithm first we extract the candidate shot boundaries using color histograms and then determine using edge matching and luminance compensation if they are shot boundaries or luminance changes. If the scene contains trivial brighness variations, the edge matching and luminance compensation are performed only for shot boundaries. In experimental results, the proposed method gives remarkably a high performance and efficiency than the conventional methods with the similar computational complexity.