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141.
JaeHyunKim JounHoLee JiChulLim ChangHoonLee MooHyoungSong JuYeonYoon HeeDongChoi JeomJaeKim ChangHoOh SangDeogYeo 李路海 《现代显示》2004,31(5):31-33
薄膜晶体管液晶电视(TFT-LCD TV)因为具有薄、轻、紧凑和可随意放置的特点,已经占据了大部分电视机市场。除了这些物理特性以外,最重要的特性是已具有了良好像质的对比度。为了将对比度提高到1:600以上,对偏振片膜、背光源板、滤色片树脂、电极锥角和摩擦条件等都进行了研究。优化的背光板组合,光滑的电极锥角和摩擦方法的控制是提高对比度的主要控制因素。应用新开发的滤色片树脂,对获得高对比度最为有效。 相似文献
142.
Yu-Li Hsueh Jaedon Kim Ching-Fong Su Rabbat R. Hamada T. Tian C. Kazovsky L.G. 《Lightwave Technology, Journal of》2006,24(1):44-53
A sublambda traffic-grooming scheme on wavelength-division-multiplexed (WDM) rings, which is called optical burst transport (OBT), is proposed. The network protocol and architecture allow increased flexibility to tailor the transport network behavior for efficient delivery of bursty data traffic. Using different network parameters, its performance is analyzed via simulation, and the implementation issues including the media-access-control (MAC) protocol, tunable-filter controller, and burst-mode receiver are addressed. Finally, the feasibility of the OBT with an experimental testbed built by the authors is demonstrated and a streaming-video application is used to present its overall functionality. 相似文献
143.
Kwang-Chul Noh Hyeon-Cheol Lee Dae-Young Kim Myung-Do Oh 《Electronics Packaging Manufacturing, IEEE Transactions on》2008,31(2):143-149
Practical studies on the method of contamination control for yield enhancement in the cellular phone modules production line were carried out. A contamination control method was proposed, consisting of data collection, data analysis, improvement action, verification, and implementation of control. The partition check method and the composition analysis for data collection and data analysis were respectively used in the cellular phone modules manufacturing process, and these methods were evaluated by the variation of yield loss before and after implementing the actions for improvement. In the partition check method, the critical process step was selected, and yield loss reduction through improvement actions was observed, whereas in the composition analysis, critical sources were selected, and yield loss reduction through improvement actions was investigated. From the results, it is concluded that the partition check and the composition analysis are effective solutions for contamination control in cleanroom production lines. 相似文献
144.
Effects of barium on the nonlinear electrical characteristics and dielectric properties of SnO2-based varistors
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The effects of barium on electrical and dielectric properties of the SnO_2·Co_2O_3·Ta_2O_5 varistor system sintered at 1250℃ for 60min were investigated. It is found that barium significantly improves the nonlinear properties. The breakdown electrical field increases from 378.0 to 2834.5V/mm, relative dielectric constant (at 1kHz) falls from 1206 to 161 and the resistivity (at 1kHz) rises from 60.3 to 1146.5kΩ·cm with an increase of BaCO_3 concentration from 0mol% to 1.00mol%. The sample with 1.00mol% barium has the best nonlinear electrical property and the highest nonlinear coefficient (α=29.2). A modified defect barrier model is introduced to illustrate the grain-boundary barrier formation of barium-doped SnO_{2}-based varistors. 相似文献
145.
Kurian A.P. Puthusserypady S. Su Myat Htut 《Wireless Communications, IEEE Transactions on》2005,4(3):984-989
In this paper, a novel direct sequence/spread spectrum (DS/SS) communication system is proposed. This scheme exploits the two-dimensional complex valued chaotic Ikeda map as the spreading sequences. With this double spreading DS/SS system, the effect of multiple access interference can be mitigated by choosing the spreading sequences with appropriate cross-correlation properties. The performance of the system is assessed and demonstrated in a multiuser environment by means of computer simulation with additive white Gaussian noise, Rayleigh fading, and selective fading channel conditions. These studies reveal that the proposed system significantly outperforms the Gold code DS/SS-BPSK system in synchronous channel conditions. In asynchronous case, the improvement is substantial for low signal-to-noise ratios. 相似文献
146.
In this paper an extension of the (r|X
p
)-medianoid on networks introduced by Hakimi (1983) is studied. In this extension the customer considers not only the distance
but some characteristics of the facilities such as store size, quality of service and parking space. A new firm wants to establishr new facilities which have to compete with thep facilities that already exist in the market. The entry firm wants to find their locations and characteristics to maximize
profits. Three different customer choice rules (binary, partially binary and proportional preferences) are considered. Some
discretization results are obtained and a resolution procedure is proposed. The problem is solved combining a global search
algorithm based on a branch and bound procedure with some combinatorial heuristics (greedy, interchange, and tabu search).
Some computational experiences are presented.
Partially supported by Ministerio de Ciencia y Tecnología (Spain) and FEDER, grant BFM2002-04525-C02-01. 相似文献
147.
148.
Yanqing Tian Xiaohe Xu Yingying Zhao Xinyi Tang Fengyu Su Xiaoguang Zhao Enle Zhou 《Liquid crystals》1995,19(3):295-300
The synthesis of three new series of chiral Schiff's bases containing benzilideneaniline and 2-hydroxybenzilideneaniline moieties as mesogenic cores is presented. Differential scanning calorimetry, optical polarizing microscopy and X-ray diffraction measurements were used to study the phase transition temperatures and behaviour. The results reveal that most of these materials show chiral smectic mesomorphism. 相似文献
149.
Z P Li C S Tang J Y Su 《Science in China. Series B, Chemistry, life sciences & earth sciences》1991,34(5):599-605
Results from a systematic experiment on isolated perfused rat heart and isolated myocytes of adult rat showed that the mechanism of calcium influx during myocardial ischemia-reperfusion is due to the development of intracellular sodium overload during ischemic period; on reperfusion, the high intracellular Na+ content activated the reverse direction of Na(+)-Ca2+ exchange over myocardial sarcolemma (SL), thus a large quantity of extracellular Ca2+ fluxed over the SL to the intracellular space, forming a condition of intracellular Ca2+ overload, which leads to irreversible damage of the myocardium. 相似文献
150.
提出了一种用于修正光学神经网络硬件系统误差的虚拟神经网络模型,光学实验结果表明该网络能够有效地消除硬件系统误差对实验结果的影响。 相似文献