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891.
指出了MRED算法的局限性,并利用一个二阶指数许可函数来设计非线性自适应控制算法,避免了单一静态阈值参数的不足,实现了许可控制的平滑化.实验仿真结果表明:该算法有效提高了集群利用率,避免了集群负载崩溃情况,提高了系统的稳定性与可靠性. 相似文献
892.
Daifeng Zha Tianshuang Qiu 《International Journal of Adaptive Control and Signal Processing》2006,20(5):213-223
We proposed neural network structures related to multilayer feed‐forward networks for performing blind source separation (BSS) based on fractional lower‐order statistics. As alpha stable distribution process has no its second‐ or higher‐order statistics, we modified conventional BSS algorithms so that their capabilities are greatly improved under both Gaussian and lower‐order alpha stable distribution noise environments. We analysed the performances of the new algorithm, including the stability and convergence performance. The analysis is based on the assumption that the additive noise can be modelled as alpha stable process. The simulation experiments and analysis show that the proposed class of networks and algorithms is more robust than second‐order‐statistics‐based algorithm. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
893.
894.
Jang‐Uk Shin Su Hwan Oh Yoon‐Jung Park Sang‐Ho Park Young‐Tak Han Heekyung Sung Kwang Ryong Oh 《ETRI Journal》2007,29(4):452-456
Very compact 4‐channel 200‐GHz‐spacing external cavity lasers (ECLs) were fabricated by hybrid integration of reflection gratings and superluminescent laser diodes on a planar lightwave circuit chip. The fifth‐order gratings as reflection gratings were formed using a conventional contact‐mask photo‐lithography process to achieve low‐cost fabrication. The lasing wavelength of the fabricated ECLs matched the ITU grid with an accuracy of ×0.1 nm, and optical powers were more than 0.4 mW at the injection current of 80 mA for all channels. The ECLs showed single mode operations with more than 30 dB side lobe suppression. 相似文献
895.
D. C. Li D. L. Yu J. L. He S. M. Liu Y. J. Tian O. Yanagisawa M. Kiritani 《Materials Science and Engineering: A》2003,350(1-2):190-194
CNx precursor powders (composition: 33.76 at.% C, 49.53 at.% N and 16.71 at.% H) having a turbostratic structure were obtained by pyrolyzing melamine. Following spark discharge treatment, the precursor becomes more ordered in structure. The order was increased with increasing treatment time. Photoluminescence (PL) analysis confirmed that the spark discharge had only a slight effect on the energy band of the turbostratic CNx powder, namely a blue shift of 11 nm in the emission spectrum of the precursor. By contrast, the high-speed impact treatment clearly promoted the mass transfer between the CNx particles. 相似文献
896.
897.
898.
1 Introduction Artificial neural networks have been extensively applied in various fields of science and engineering. Why is so is mainly because the feedforward neural networks (FNNs) have the universal approximation capability[1-9]. A typical example of… 相似文献
899.
In this article, the new grid finite‐difference time‐domain (NG‐FDTD) method is applied to calculate the dispersion curves of electromagnetic band‐gap structures, and the dispersion characteristics of three magnetic‐anisotropic medium EBG structure are obtained using the NG‐FDTD method. According to these results, we can conclude that the EBG structure of a magnetic‐anisotropic medium, in which the permeability of nondiagonal elements is real, has a much larger band‐stop than that of isotropic EBG. Other magnetic‐anisotropic EBG structures can also increase the first band‐stop. © 2005 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2005. 相似文献
900.
Alev Topuzoğlu Arne Winterhof 《Applicable Algebra in Engineering, Communication and Computing》2005,16(4):219-228
Nonlinear congruential methods are attractive alternatives to the classical linear congruential method for pseudorandom number
generation. Generators of higher orders are of interest since they admit longer periods. We obtain lower bounds on the linear
complexity profile of nonlinear pseudorandom number generators of higher orders. The results have applications in cryptography
and in quasi-Monte Carlo methods. 相似文献