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991.
G. Oversluizen T. Dekker M. F. Gillies S. T. De Zwart 《Journal of the Society for Information Display》2004,12(1):51-55
Abstract— The trade‐off between PDP efficacy improvement and driving voltages was investigated for several design factors. It was found that for a proper combination of an increased Xe content, cell design, and the use of a TiO2 layer combined with “non‐saturating” phosphors, a large increase in both efficacy and luminance can be realized at moderately increased drive voltages. In a 4‐in. color test panel, a white efficacy of 5 lm/W and a luminance of 5000 cd/m2 was obtained for sustaining at 260 V in addressed condition. 相似文献
992.
Reiji Hattori Shuhei Yamada Yoshitomo Masuda Norio Nihei 《Journal of the Society for Information Display》2004,12(1):75-80
Abstract— We have developed new powder materials that exhibit liquid behavior, which can lead to the realization of novel bistable and reflective displays having paper‐white appearance, high contrast, and quick response. Two types of display were demonstrated, one had 160 × 160 array of pixels and the other had 320 × 320 in a 3.1‐in.‐diagonal viewable image size corresponding to 66 and 132 dpi, respectively. These displays were driven by passive‐matrix addressing. The displays showed a reflectivity of more than 41%, a contrast more than 1:10, and a pixel response time of less than 0.2 msec. The seven‐segment display for use in clocks was also demonstrated. 相似文献
993.
Joost P. A. Vogels Stephen I. Klink Roel Penterman Henk De Koning Edzer E. A. Huitema Dirk J. Broer 《Journal of the Society for Information Display》2004,12(4):411-416
Abstract— In this article, second‐generation liquid‐crystal displays (LCDs) made by Paintable LCD technology is presented. With this technology, LCDs are manufactured by a sequence of simple coating and UV curing processes. Since the process can be carried out on plastic substrates and the stack of optical layers is only tens of micrometers thick, the resulting LCDs are ultra‐thin and flexible. 相似文献
994.
995.
In this paper, the problem of observer-based robust fault detection (RFD) for nonlinear networked systems with stochastic interval delay is investigated. By employing the information of probabilistic distribution of networked-induced time-varying delay, the observer-based fault detection filter as residual generator and a proposed performance index as objective function, the RFD of nonlinear networked systems is formulated as an optimization problem. The desired fault detection filter is constructed in terms of certain linear matrix inequalities, which depend on not only delay-interval but also delay-interval-occurrence-rate. Especially, the sub-optimal trade-off of strong robustness from residual signal to disturbance and parameter uncertainty, as well as high sensitivity to fault is obtained by a repeated application of a two-objective optimization algorithm. Numerical simulations are given to illustrate the effectiveness of proposed techniques. 相似文献
996.
Tuning PI controllers for stable processes with specifications on gain and phase margins 总被引:2,自引:0,他引:2
Kaya I 《ISA transactions》2004,43(2):297-304
In industrial practice, controller designs are performed based on an approximate model of the actual process. It is essential to design a control system which will exhibit a robust performance because the physical systems can vary with operating conditions and time. Gain and phase margins are well known parameters for evaluating the robustness of a control system. This paper presents a tuning algorithm to design and tune PI controllers for stable processes with a small dead time while meeting specified gain and phase margins. Simulation examples are given to demonstrate that the proposed design method can result, in a closed-loop system, in better performances than existing design methods which are also based on user-specified gain and phase margins. 相似文献
997.
网络化测控设备间的时间同步 总被引:1,自引:0,他引:1
为使广域网络范围内的测控设备同步工作,必须准确的计算出网络数据传输的时延。依据排队论,本文提出并证明了准确的网络节点模型和数据延时分布统计模型,以此为基础计算出数据报在互联网上传输的精确时延并给出时延修正方法。实验数据论证了模型的正确性。最后提出了广域自动测试系统内设备的同步解决方案,时间同步精度在10~50μs范围内。 相似文献
998.
为解决相空间重构中多变量时滞参数难以同时选择的问题,提出一种基于最大独立互相关的时滞计算方法.将响应变量序列分段处理;对各段曲面拟合并将观测变量序列代入拟合函数;迭代运算至互相关最小,得到最优时滞.对最大独立互相关算法与遗传神经网络、互信息法、极大联合熵法进行对比实验,并引入联合递归图与共有近邻比值法作为评价方法,结果表明:最大独立互相关算法克服了传统方法的不足.选取某矿井下进风巷、上隅角、工作面和回风巷4个位置瓦斯浓度的真实数据进行四变量最优时滞选择实验并与互信息法对比,最大独立互相关算法的时滞计算结果为16-3-10-11,共有近邻比为0.58,联合递归密度为0.34%,优于传统方法.提出算法能够应用于实际多变量分析,具有一定实用价值. 相似文献
999.
作为废弃液晶面板的重要组成部分,液晶材料中含有芳环、氰基、氟、氯、溴等基团,若随意丢弃或采用不当的处置方式将严重污染环境。本研究拟利用热解处理技术实现对液晶材料的无害化处理,探究了废旧薄膜晶体管液晶显示器中液晶材料的热解特性。液晶材料的热重分析结果表明,液晶材料的主要热解温度为300~500?C;热解实验表明,热解温度对液晶材料热解产物的影响较大,其中300?C和500?C条件下主要生成了双环己烷类、联苯类等化合物,而在800?C条件下主要生成多环芳烃;此外,考察了热解温度、氮气流量及固相停留时间对液晶去除率的影响,在优化条件下液晶的去除率可达94.2%。本研究为废旧液晶面板中液晶材料的无害化处理提供了技术参数和理论参考。 相似文献
1000.
This paper presents a new system configuration and a design method to improve control performance for a system with an input time delay and disturbances. The equivalent-input-disturbance approach is extended to handle a time-delay system. It is combined with the Smith predictor to reject disturbances. A delay-dependent stability condition is devised in terms of a matrix inequality by using the free-weighting matrix approach. The gain of the observer is designed by applying the cone complementary linearization method to the matrix inequality. A numerical example demonstrates the validity of the method. 相似文献