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141.
针对多指标面板数据的样品分类和历史时期划分问题,从多元统计分析理论角度提出一个多指标面板数据的融合聚类分析方法。该方法改进了多指标面板数据的因子分析和系统聚类方法,依据Fisher有序聚类理论,构造了Frobenius范数形式的离差平方和函数,提出了多指标面板数据的有序聚类方法。实证结果表明,该方法能够满足系统分析的统一性要求,保证指标之间的不相关;能够克服时间维度上均值处理造成的偏误,信息损失较少;能够解决面板数据有序聚类的问题;弥补了单一分析的片面性和局限性。 相似文献
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143.
In this study, we suggest a customized model describing optical phenomena at the surface of a lenticular array for autostereoscopic displays in a mathematical form and analyzed the optical characteristics of lenticular array for the first time. We checked the validity of our mathematical model by examining and comparing our result with conventional lens theory. Monte Carlo simulations were performed to obtain the angular distribution of light from each sub-pixel corresponding to each views under actual design conditions. From the results, we think the optical model is very useful for designing optical parameters of autostereoscopic displays. 相似文献
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145.
康建兵 《电子工业专用设备》2008,37(9)
在等离子屏、LCD、TFT等平板显示器生产电子工业领域中,曝光显影是生产工艺中的重要组成部分。由于各类显影废液中含有多种化学成分和昂贵的工业原料,因此进行显影废液的处理与再生对生产成本的控制及环境保护都是相当重要的环节,远心分离技术正是在这种背景下被引入到该领域,并且取得了很好的环保效果和极高的经济效益。 相似文献
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147.
For augmented reality and virtual reality displays, high-resolution density, high luminance, and fast response time are critically needed. High-resolution density helps eliminate the screen-door effect; high luminance and fast response time enable low duty ratio operation, which plays a key role for suppressing image blurs. By using a low viscosity material and new diamond-shaped electrode configuration, we demonstrate a fringe field switching liquid crystal display, abbreviated as d-FFS LCD, with high transmittance, fast grey-to-grey response time, low operation voltage, wide viewing angle, and indistinguishable colour shift and gamma shift. We also investigate the rubbing angle (α) effects on transmittance and response time. When α = 0°, the virtual wall effect is strong, resulting in fast response time but compromised transmittance. When α ≥ 1.2°, the virtual walls disappear, as a result, the transmittance increases dramatically, but the trade-off is in slower response time. 相似文献
148.
Microperforated panel (MPP) absorbers are promising as a basis for the next-generation of sound absorbing materials. MPPs are typically made of a thin metal or plastic panel. However, thin limp panels are generally not suitable as an interior finish of room walls because they do not have sufficient strength, which prevents practical application of MPPs as an interior finish of room walls. In order to overcome the lack of appropriate strength required for room walls, it is possible to make an MPP out of a thick panel. However, thick MPPs are usually not efficient because the resistance and/or reactance become too high. In this study, trial production of thick MPPs and measurement of their normal absorption coefficients were carried out. Results show that efficient absorption can be given with a thick MPP by using a tapered perforation. 相似文献
149.
随着显示技术的不断发展,集成触摸屏的液晶显示(LCD)在日常生产与生活中得到了广泛的应用。良好的触屏显示在人机交互方式上扮演着重要角色。然而,外挂式触摸屏在薄化后,触控感测部件和LCD驱动部件之间的距离减小,造成两者之间更紧密的耦合,导致LCD对触摸屏的噪声干扰更加严重,造成误触摸情况发生。为此,我们通过本文研究发现,调节源极数据驱动IC的内置功能及数据信号的驱动方式,可有效改善噪声干扰问题。首先,根据TFT面板阵列的排布,针对性调节源极数据驱动信号,观察噪声干扰的程度。实验结果表明:降低源极数据驱动能力,或更改数据信号的驱动方式为H2Dot时,噪声最大的sub V-stripe画面下的噪声干扰峰值可下降75%。基于上述解决方案,达到了降低噪声干扰的目的,提供给用户更精准、灵敏的触控体验。 相似文献
150.
Electrochromic materials reversibly change colors by redox reactions depending on the oxidation states. To utilize electrochromic materials for active‐matrix display applications, an electrochromic display (ECD) requires simultaneous implementation of various colors and a fine‐pixelation process. Herein, flexible and transparent ECDs with simultaneously implementable subpixelated EC gels by sequential multiple patterning are successfully demonstrated. Ionic liquid‐based EC gels of monoheptyl‐viologen, diheptyl‐viologen (DHV), and diphenyl‐viologen (DPV) are used to create the colors of ECDs: magenta, blue, and green, respectively. Especially, to realize an improved green color, DHV–DPV composite gels are synthesized. Three EC gels exhibit stable properties without degradation during repetitive operation. Moreover, a transmittance greater than 90% is maintained in a bleached state, which is sufficient for application as a transparent display. The subpixelation process for multicolored‐flexible ECDs is designed to facilitate both easy fabrication and rapid operation with various patterns at low cost. The subpixelated EC gels using a film mask can be implemented to a minimum size of 200 µm. Furthermore, the subpixelated flexible ECDs exhibit high durability even after 1000 cycles of mechanical bending tests at a bending radius of 10 mm. Therefore, these EC materials can be used directly for flexible and transparent active‐matrix displays. 相似文献