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51.
由电压型运算放大器组成的精密整流电路要严格地匹配电阻才能获得精密全波整流波形.本文给出一种具有CCⅡ电路特性由运算放大器AD844所构成的电流模精密整流电路.无需匹配电阻就可输出良好的精密全波整流波形.且具有输入电压范围大,频带宽等特点. 相似文献
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This paper redefines three measures of element s-importance for 2-state systems regardless of s-coherence, presents the calculation methods of these measures, and gives a new method to calculate the system time-specific failure and recovery frequencies. A poor point in the literature in extending methods for evaluating the s-importance of elements of s-coherent system to non-coherent system is pointed out. An example illustrates these definitions and calculation methods. 相似文献
54.
本文简单地回顾了提高VLSI测试效率所采用的一些手段,讨论了在ASIC测试问题研究中出现的一些新观点、新方法、新动向,以及所取得的成果。在此基础上,文章阐明了ASIC测试技术的发展方向,并着重论述了可望在未来得到发展的,针对ASIC的功能测试方法。 相似文献
55.
Haitao Zhang Zonghai Chen Yongji Wang Ming Li Ting Qin 《International Journal of Adaptive Control and Signal Processing》2006,20(2):53-76
Laguerre Functional Model has many advantages such as good approximation capability for the variances of system time‐delay, order and other structural parameters, low computational complexity, and the facility of online parameter identification, etc., so this model is suitable for complex industrial process control. A series of successful applications have been gained in linear and non‐linear predictive control fields by the control algorithm based on Laguerre Functional Model, however, former researchers have not systemically brought forward the theoretical analyses of the stability, robustness, and steady‐state performance of this algorithm, which are the keys to guarantee the feasibility of the control algorithm fundamentally. Aimed at this problem, we introduce the principles of the Incremental Mode Linear Laguerre Predictive Control (IMLLPC) algorithm, and then systemically propose the theoretical analyses and proofs of the stability and robustness of the algorithm, in addition, we also put forward the steady‐state performance analysis. At last, the control performances of this algorithm on two different physical industrial plants are presented in detail, and a number of experimental results validate the feasibility and superiority of IMLLPC algorithm. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
56.
The Tikhonov regularisation technique is widely used in the solution of inverse scattering problems. One of the difficulties in applying this technique is the proper selection of the associated regularisation parameter. Based on a stochastic model of the reconstruction process, a simple method is presented for selecting this parameter for an efficient implementation of various microwave imaging methods 相似文献
57.
Sun Linzhi Luo Yi Zhang Yanan Sun Ping Qin Xinjie Gong ZhenbangPrecision Machinery Institute Shanghai University Shanghai China 《机械工程学报(英文版)》2002,15(4):303-307
An experimental bimorph piezoelectric element (PZT) actuator for small pipe robot is developed. The robot can move in φ20 mm pipe, and can carry a CCD camera for detecting cracks or fine holes on inner surface of pipe. The velocity of the robot can reach 17~22 mm/s for vertical pipe up/down, respectively. Moving principle and its performance characteristics are presented. 相似文献
58.
聚乙烯基吡咯烷酮的生产与市场 总被引:1,自引:0,他引:1
文章介绍了聚乙烯基吡咯烷酮国内外生产现状、市场需求和发展趋势,重点介绍其合成技术进展与应用,并就其发展提出一些建议。 相似文献
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The basic concept of a novel frequency-based on-line expert system (FBOLES) approach for on-line fault diagnoses in nuclear power plants has been presented previously. This paper reports further progress, and includes how to express the uncertainties of expert opinion in knowledge-bases and propagate then in inferences, and how to deal with imperfect knowledge-bases. It also describes the main elements of FBOLES and outlines how the system works under complex conditions including the dynamic behavior of signals during accidents, multiple failures, and on-line changes of plant operation mode. Its ability to diagnose root causes of accidents has been tested using the main steam and feedwater condensate systems of a full-scale, three-loop, 950 MW nuclear power plant simulated by the Tsinghua simulator. So far the results seem good. 相似文献