• Title/Summary/Keyword: information barrier

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Analysis of Energy Flow and Barrier Rib Height Effect using Ray-Optics Incorporated Three-dimensional PDP Cell Simulation

  • Chung, Woo-Joon;Jeong, Dong-Cheol;Whang, Ki-Woon;Park, Jae-Hyeung;Lee, Byoung-Ho
    • Journal of Information Display
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    • v.2 no.4
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    • pp.46-51
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    • 2001
  • Using ray-optics code incorporated with three-dimensional PDP cell simulation, we have analysed the energy flow in the PDP cell from the electric power input to the visible light output. Also, the visible light output profile and viewing angle distribution were obtained. We applied our code to the analysis of the barrier rib height effect on the visible light luminance and efficiency of the sustaining discharge. Although cells with higher barrier rib generate more VUV photons, less ratio of visible photons are emitted toward front panel due to the shadow effect. Thus, there exists optimal barrier rib height giving the highest visible luminance and efficiency. This kind of code can be a powerful tool in designing cell geometry.

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Electrical Characteristics of Metal/n-InGaAs Schottky Contacts Formed at Low Temperature

  • 이홍주
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.5
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    • pp.365-370
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    • 2000
  • Schottky contacts on n-In$\_$0.53//Ga$\_$0.47//As have been made by metal deposition on substrates cooled to a temperature of 77K. The current-voltage and capacitance-voltage characteristics showed that the Schottky diodes formed at low temperature had a much improved barrier height compared to those formed at room temperature. The Schottky barrier height ø$\_$B/ was found to be increased from 0.2eV to 0.6eV with Ag metal. The saturation current density of the low temperature diode was about 4 orders smaller than for the room temperature diode. A current transport mechanism dominated by thermionic emission over the barrier for the low temperature diode was found from current-voltage-temperature measurement. Deep level transient spectroscopy studies exhibited a bulk electron trap at E$\_$c/-0.23eV. The low temperature process appears to reduce metal induced surface damage and may form an MIS (metal-insulator-semiconductor)-like structure at the interface.

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Analysis of the Water Quality by Various Gate Operation Effects at Nakdong Estuary Barrier (낙동강하구둑 수문운영에 따른 수질 영향 분석)

  • Lee, Sang Jin;Ryoo, Kyong Sick;Hwang, Man Ha;Lee, Sang Uk
    • Journal of Korean Society on Water Environment
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    • v.24 no.6
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    • pp.651-658
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    • 2008
  • Estuary barrier is a hydraulic structure constructed to supply safely water as protecting chlorine penetration of sea water. However, the barrier brings about a problem which decreases original functions of estuary because hydraulic ecology was disrupted as obstructing natural water exchange between fresh water and sea water. It is important to supply Enough fresh water in the estuary ecosystem. But it is possible to reduce the problems brought from barrier throughout efficient water gate operation of estuary barrier. It was shown in this study that the environmental effect of estuary in Nakdong river was investigated according to the control of water level. Also, the basic information about the effective water gate operation was provided. The analysis results showed that the release rate of estuary was increased about 20% as changing the operational water levels. This helps supplying fresh water durably to the mixing zone. Also, CE-QUAL-W2 model was utilized to assess water quality. The values of BOD and COD were not changed in estuary area. From the result, it was analyzed the effect of water quality according to the water gate operation was not indicated.

패스트푸드점의 로하스 이미지, 고객만족, 전환장벽 및 재방문의도의 영향관계에 관한 연구

  • Lee, Seung-Hui;Jeong, Yeon-Gyo;Kim, Hye-Gyeong;Jo, Yeong-Jun
    • Proceedings of the Korea Society for Industrial Systems Conference
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    • 2008.10b
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    • pp.199-206
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    • 2008
  • This paper aimed to exam relationship of lohas image, costomer satisfaction, switching barrier, revisit intention to fast food store. To accomplish this purpose, this study examined previous studies and summarized. 400 questionaries were distributed to the people living in Daegu/Gyeong-Buk. 381 questionaries were obtained and 331 data were analyzed by frequencies, correlation, multiple regression. The results of this study are as follows; First, it is shown that lohas image have a positive influence on the customer satisfaction(p<0.01). Second, it is shown that lohas image have a positive influence on the switching barrier(p<0.01). Third, it is shown that customer satisfaction have a negative influence on the switching barrier(p<0.57). Fourth, it is shown that lohas image have a positive influence on 1he revisit intention(p<0.05). Fifth, it is shown that customer satisfaction have a positive influence on 1he revisit intention(p<0.01). Sixth, it is shown that switching barrier have a positive influence on 1he revisit intention(p<0.01). This study, however, have limitation in obtained sample and area. The future study should consider these limitation to improve model applicability in practice.

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Impact ionization rate of the highly-doped AlGaAs/GaAs quantum well (고준위 도핑된 AlGaAs/GaAs 양자 우물의 충돌 이온화율)

  • 윤기정;황성범;송정근;홍창희
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.33A no.4
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    • pp.121-128
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    • 1996
  • The impact ionization rate of thethighly-doped AlGaAs/GaAs quantum well structure is calculated, which is an important parameter ot design theinfrared detector APD and the novel neural device. In conjunction with ensemble monte carlo method and quantum mechanical treatment, we analyze the effects of the parameters of quantum well structure on the impact ionization rate. Since the number of the occupied subbands increases while the energy of the subbands decreases as the width of quantum well increases, the impact ionization rate increases in the range of th esmall well width but gradually the increament slows down and is finally saturated. Due to the effect of the energy of the injected electrons into the quantum well and the tunneling through the barrier, the impact ionization rate increases for the range of the small barrier width and decreases for the range of the large barrier width. Thus, there exists a barrier width to maximize the impact ionzation rate for a mole fraction x, and the barrier width moves to the larger vaue as the mole fraction x increases. The impact ionization rate is much more sensitive to the variation of the doping density than that of the other quantum well parameters. We found that there is a limit of the doping density to confine the electronics in the quantum well effectively.

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Autostereoscopic Display based on Dual Layer Parallax Barrier (이중 계층 패렐랙스 배리어 기반의 무안경식 3D 디스플레이)

  • Lee, Hyun;Lee, Eung-Don;Um, Gi-Mun;Cheong, Won-Sik;Lee, Sung-Jung
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.48 no.6
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    • pp.68-76
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    • 2011
  • We introduce a parallax barrier type autostereoscopic display in order to overcome the limited viewing angle of the conventional parallax barrier type displays. The proposed method adopts a special structure of double pairs of ITO that have a common TN-LC at the core of the conventional parallax barrier. Compared with the conventional parallax barrier type displays, the proposed display uses moving parallax barriers and eye tracking system to make stereoscopic view images adapted to the movement of viewer. We implemented a prototype of the proposed dual layer parallax barrier system, and verified that the proposed autostereoscopic display maintains seamless 3D views even when a viewer's head is moving.

A Hardware Barrier Synchronization using Multi -drop Scheme in Parallel Computer Systems (병렬 컴퓨터 시스템에서의 Multi-drop 방식을 사용한 하드웨어 장벽 동기화)

  • Lee, June-Bum;Kim, Sung-Chun
    • Journal of KIISE:Computer Systems and Theory
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    • v.27 no.5
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    • pp.485-495
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    • 2000
  • The parallel computer system that uses parallel program on the application such as a large scale business or complex operation is required. One of crucial operation of parallel computer system is synchronization. A representative method of synchronization is barrier synchronization. A barrier forces all process to wait until all the process reach the barrier and then releases all of the processes. There are software schemes, hardware scheme, or combinations of these mechanism to achieve barrier synchronization which tends to use hardware scheme. Besides, barrier synchronization lets parallel computer system fast because it has fewer start-up overhead. In this paper, we propose a new switch module that can implement fast and fault-tolerant barrier synchronization in hardware scheme. A proposed barrier synchronization is operated not in full-switch-driven method but in processor-driven method. An effective barrier synchronization is executed with inexpensive hardware supports. Therefore, a new proposed hardware barrier synchronization is designed that it is operated in arbitrary network topology. In this paper, we only show comparison of barrier synchronization on Multistage Interconnection Network. This research results in 24.6-24.8% reduced average delay. Through this result, we can expect lower average delay in irregular network.

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Stability of ITO/Buffer Layer/TPD/Alq3/Cathode Organic Light-emitting Diode

  • Chung, Dong-Hoe;Ahn, Joon-Ho;Oh, Hyun-Seok;Park, Jung-Kyu;Lee, Won-Jae;Choi, Sung-Jai;Jang, Kyung-Uk;Shin, Eun-Chul;Kim, Tae-Wan
    • Transactions on Electrical and Electronic Materials
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    • v.8 no.6
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    • pp.260-264
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    • 2007
  • We have studied stability in organic light-emitting diode depending on buffer layer and cathode. A transparent electrode of indium-tin-oxide(ITO) was used as an anode. An electron injection energy barrier into organic material is different depending on a work function of cathodes. Theoretically, the energy barriers for the electron injection are 1.2 eV, -0.1 eV, and 0.0 eV for Al, LiAl, and LiF/Al at 300 K, respectively. We considered the cases that holes are injected to organic light-emitting diode. The hole injection energy barrier is about 0.7 eV between ITO and TPD without buffer layer. For hole-injection buffer layers of CuPc and PEDOT:PSS, the hole injection energy barriers are 0.4 eV and 0.5 eV, respectively. When the buffer layer of CuPc and PEDOT:PSS is existed, we observed the effects of hole injection energy barrier, and a reduction of operating-voltage. However, in case of PVK buffer layer, the hole injection energy barrier becomes high(1.0 eV). Even though the operating voltage becomes high, the efficiency is improved. A device structure for optimal lifetime condition is ITO/PEDOT:PSS/TPD/$Alq_3$/LiAl at an initial luminance of $300cd/m^2$.

Planning of Barrier Free Pedestrian Safety Devices (Barrier Free 보행안전시설 계획)

  • Nam, Doohee
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.13 no.2
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    • pp.217-223
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    • 2013
  • Population aging is a shift in the distribution of a country's population towards older ages. This is usually reflected in an increase in the population's mean and median ages, a decline in the proportion of the population composed of children, and a rise in the proportion of the population that is elderly. Population ageing is widespread across the world. Barrier-free or Design for All concept consists of modifying buildings or facilities so that they can be used by people who are disabled or have physical impairments. Design for All criteria are aimed at ensuring that everyone can participate in the Information society. Safety-related products being easy to adapt according to different needs, or using standardized interfaces that can be accessed simply by using assistive technology. To this end, policy makers and service providers, especially in the ubiquitous technologies, produce new technologies, products, services and applications for pedestrians.