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101.
刘建平 《电信工程技术与标准化》2008,21(6):32-38
本文研究了ROADM的技术优势,主要结构类型,涉及的关键技术以及存在的问题,并分析了当前ROADM标准化进展情况与发展趋势,还介绍了当前设备现状和现网应用情况。 相似文献
102.
103.
A new multifunction filter using minimum components is presented. This filter which possesses single input and four outputs can simultaneously generate second-order highpass, bandpass, and lowpass filtering functions at individual output terminals. The filter has the following merits; it uses only two grounded capacitors which makes it suitable for integrated circuit implementation, no matching condition is required, offering multifunction outputs and has low passive and active sensitivities. Experimental results agree very well with the theoretical result 相似文献
104.
研制成功了128×128元PtsiIRCCD,获得了清晰的室温目标热像。文章叙述了该摄像机驱动逻辑电路的设计、驱动方式的研究和视频信号、数字信号的处理。 相似文献
105.
首次提出了G(F4′)条件,给出了G(F4′)条件的两个等价关系,得到了加强形式的停止定理和强鞅的一个等价关系. 相似文献
106.
刘爽 《微电子学与计算机》1998,15(2):26-28
本文给出并发表达式语言的文法,并描述了Petri网编辑器的语法分析过程和中间代码的产生过程。解决了Petri网在计算机中的存贮结构问题,处理了可能会出现的重名变量,实现了从井发表达式语言到安全标号的Petri网的转换工作。 相似文献
107.
108.
Least-squares finite difference (LSFD) method, one of mesh-free methods, is used to solve slider air bearings problem through discritizing the generalized Reynolds equation into nonlinear systems of algebraic equations. Two approximation schemes for the linearization of these equations are presented and compared. And, some new techniques to search supporting points for the reference node in the mesh-free method were proposed and explored. Therefore, these improvements eliminate some potential limitation of the LSFD method previously published and further facilitate its employment in complex slider models. Advanced step slider as an example of negative pressure sliders is simulated and verified using the improved LSFD mesh-free method in head disk systems. 相似文献
109.
Qing Zhong Liu 《Microwave Theory and Techniques》1992,40(2):329-337
Unified analytical expressions have been derived for calculating the resonant frequencies, transimpedance and equivalent input noise current densities of the four most widely used tuned optical receiver front ends built with FETs and p-i-n diodes. A more accurate FET model has been used to improve the accuracy of the analysis. The Miller capacitance has been taken into account, and its impact on the performances of the tuned front ends has been demonstrated. The accuracy of the expressions has been verified by Touchstone simulations. The agreement between the calculated and simulated performances of the front ends is very good. The expressions can be used to investigate the performances of different tuned front ends in a very simple way and provide a good starting point for further computer optimizations of the front ends 相似文献
110.
An adaptive optical sequence generation scheme has been described in a nonlinear optical ring which exhibits chaotic dynamics. The adaptation is based on avoidance of collisions between the ring output and signals from another source. It is shown that collision-avoiding sequences can be autonomously selected via chaotic mode transitions induced by the feedback of collision signals. Experimental results demonstrate that the method can be successful for various collision signal patterns with different periods and pulsewidths. The mechanism of inducing chaos with collision signals is examined both experimentally and with numerical simulations and the results verify the effectiveness of the proposed adaptation method. A possible application of the proposed signal generation scheme in intelligent optical communication networks is mentioned 相似文献