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自20世纪90年代DWDM系统商用以来,已迅速成为长途传输的主流方式.2000年以来,铁路以8横8纵为基础,相继建成了五大DWDM基础光传输网络环.如今伴随DWDM技术的广泛普及,传输网的维护与传统方式相比也有了较大区别.通过分析DWDM优势,以及铁路应用现状,结合相关文献和工作经验与大家讨论一下几种DWDM故障判断与定位的常用方法. 相似文献
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An oscillator(OSC)with a metamaterial resonator based on high-Q is designed to improve the phase noise in Kband.The proposed metamaterial resonator is a lattice structure resonator(LSR)that is designed to be high-Q by a strong coupling of E-field at the resonance frequency.Thus the output of OSC is about 12.5dBm at the f0.The phase noise is 109.477dBc/Hz at 100kHz offset frequency. 相似文献
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由于脉宽调制器对振荡器频率要求越来越高,文中设计了一种新型的可产生高频脉冲的振荡电路,分析了它的工作原理,提出了该振荡器的关键参数确定的方法,并利用pspice仿真器对该电路进行了模拟与仿真,结果表明该电路可产生频率达1MHz,脉宽为零点几微秒的脉冲,符合了当前脉宽调制器对振荡器频率的要求. 相似文献
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In this study, fresh and aged Pd/(OSC–Al2O3) and Pd/(Al2O3–OSC–La2O3) metallic monoliths (OSC material Ce0.75Zr0.25O2) were used to find out the effect of La2O3 on the catalyst behaviour in dynamic oxygen storage capacity (OSC) measurements. In addition, the interaction of CO, NO and
O2 reaction compounds over the studied catalysts was investigated in order to understand the effect of La2O3 in the oxidation and reduction reactions in lean automotive exhaust gas conditions. A FT-IR gas analyser was used to analyse
the product gas composition. The presence of La2O3 on fresh and aged catalysts had negative effect on both the dynamic OSC and the activity of the catalyst. The reason for this
is the different washcoat compositions between the studied catalysts which could explain the differences in BET surface areas. 相似文献
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主要研究一类在原大系统结构上又逐个地增加了新的子系统的扩展结构大系统基于动态输出反馈的有机结构控制问题。研究了在动态输出反馈条件下扩展结构大系统的数学描述方法,利用Lyapunov稳定性和线性矩阵不等式(LMI)理论给出了此类系统鲁棒关联镇定的充分条件,得到了其动态输出反馈控制器的设计方法,结合算倒对所提出方法进行了仿真研究,结果证明了该方法的有效性。 相似文献
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In this work, thieno [3,4-b] thiophene/benzodithiophene (PTB7): [6,6]-phenyl C71-butyric acid methyl ester (PC71BM) based organic solar cell (OSC) with a new record of power conversion efficiency (PCE) of ∼7.62% has been realized using airbrush spray (AS) coating method in air ambient which can be well compatible with large-scale fabrication. By investigating the physical mechanism of AS coated blend films, a series of ternary solvent systems (TSS) are used to simultaneous optimize the surface tension and the saturated vapor pressure of solution. Therefore, different TSS further controls the morphology of PTB7:PC71BM blend films precisely and systematically. It is elucidated that the chlorobenzene (CB)/o-Xylene (o-Xy)/1, 8-diiodoctane (DIO) TSS with a ratio of 37:60:3 vol.% could lead to a homogeneous surface morphology with a decreased aggregation domain size of active layer. In addition, the high fill factor, increased PC71BM absorption and internal quantum efficiency indicate the formation of bicontinuous interpenetrating and fully percolated networks with nanostructured phase separation in BHJ blend films. Ultimately, the AS coated OSCs based on the TSS of CB/o-Xy/DIO gains a 34% enhancement in PCE, compared with the conventional CB/DIO solvent based OSCs. 相似文献
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基于正交投影的校正算法是近年来在光谱处理上显得较活跃的一种方法。本文介绍了基于正交投影的校正算法的基本原理,并对S.Wold、Fearn等人的比较成熟的5种基于正交投影的校正算法作了比较详细地介绍。最后对5种算法在谷物和柴油的近红外数据上的应用进行了比较和讨论。 相似文献
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Dynamic oxygen storage and release capability (OSC) measurement apparatus was designed to evaluate the OSC performance of ceria-based oxygen storage material. The optimum measurement condition was at a frequency of 0.1 Hz with the inlet gas-flow sequence CO (5S)→O2(5S)→CO→O2 and a flow rate of 300 ml·min^-1. Under this condition, similar regular square wave in the inlet and outlet of the reactor was obtained to guarantee the reliability of the dynamic OSC results. The dynamic OSC performance of the CeO2 and Ce0.67Zr0.33O2 mixed oxide prepared using the citric sol-gel method was studied at the optimum measurement condition with focus on both quantitative and qualitative analyses, The results reveal distinctly that Ce0.67Zr0.33O2 had better dynamic OSC performance because of its higher oxygen migration rate than CeO2. Under dynamic conditions, two CO2 production peaks occurred corresponding to the CO pulse and the O2 pulse, respectively, during the entire cycle. The intensity and ratio between the two CO2 productions were highly influenced by temperature and frequency indicating complex surface phenomena during the oxygen storage/release process, As a result, this set-up can be applied to the evaluation of ceria-based material on the OSC performance. 相似文献