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91.
92.
旅行商问题是经典的NP难组合优化问题之一,快速有效地解决旅行商问题具有重要的理论和实际意义。受自然界物种群体间相互联系的启发,提出了群体间竞争与协作的遗传算法来解决旅行商问题。该算法在迭代的过程中,每次只选择竞争力大的种群进行进化,同时为了维持各个种群间发展的平衡,对它们进行周期性的交流,能促使进化过程中中好的基因模式迅速地在各个种群中传播,提高了整体的进化速度。此算法不但能有效地维持群体的多样性,而且能提高收敛的速度。通过对旅行商问题的仿真实验,证明了该算法的可行性与有效性。 相似文献
93.
A new characterization procedure for aqueous solutions with unknown composition was proposed based on the binomial distribution
of TOC (total organic carbon) fraction in terms of a characterizing variable, the Freundlich coefficient, k, so that the solution
in question can be described by a finite number of pseudo.species identified with a certain k value. The validity and computational
accuracy of this procedure has been demonstrated by characterizing three sets of experimental data chosen from different sources.
Predictions based on this procedure yielded acceptable results that agreed closely with experimental data. 相似文献
94.
95.
在分子束外延生长的InAs/In0.52Al0.48As/InP异质结体系中,形成InAs量子线.这些InAs量子线在生长和结构方面有一些独到的特性,并介绍了本实验室在研究InAs量子线的生长和结构方面所做的工作. 相似文献
96.
97.
Xiao-Yuan Chen Jian-Xun Jin Kai-Meng Ma Ju Wen Ying Xin Wei-Zhi Gong An-Lin Ren Jing-Yin Zhang 《中国电子科技》2008,6(2):137-142
High temperature superconducting (HTS) power inductor and its control technology have been studied and analyzed in the paper. Based on the results of simulations and practical experiments, a controlled release scheme has been proposed and verified for developing a practical HTS SMES prototype. 相似文献
98.
This paper presents a novel maximum a posteriori (MAP) denoising algorithm based on the independent component analysis (ICA). We demonstrate that the employment of individual ICA transformations for signal and noise can provide the best estimate within the linear framework. The signal enhancement problem is categorized based on the distribution of signal and noise being Gaussian or non-Gaussian and the estimation rule is derived for each of the categories. Our theoretical analysis shows that under the assumption of a Gaussian noise the proposed algorithm leads to some well-known enhancement techniques, i.e., Wiener filter and sparse code shrinkage. The analysis of the denoising capability shows that the proposed algorithm is most efficient for non-Gaussian signals corrupted by a non-Gaussian noise. We employed the generalized Gaussian model (GGM) to model the distributions of speech and noise. Experimental evaluation is performed in terms of signal-to-noise ratio (SNR) and spectral distortion measure. Experimental results show that the proposed algorithms achieve significant improvement on the enhancement performance in both Gaussian and non-Gaussian noise. 相似文献
99.
100.
Xin Gu Liang Chen Zhicheng Ju Huayun Xu Jian Yang Yitai Qian 《Advanced functional materials》2013,23(32):4049-4056
Hierarchical nanocomposites rationally designed in component and structure, are highly desirable for the development of lithium‐ion batteries, because they can take full advantages of different components and various structures to achieve superior electrochemical properties. Here, the branched nanocomposite with β‐MnO2 nanorods as the back‐bone and porous α‐Fe2O3 nanorods as the branches are synthesized by a high‐temperature annealing of FeOOH epitaxially grown on the β‐MnO2 nanorods. Since the β‐MnO2 nanorods grow along the four‐fold axis, the as‐produced branches of FeOOH and α‐Fe2O3 are aligned on their side in a nearly four‐fold symmetry. This synthetic process for the branched nanorods built by β‐MnO2/α‐Fe2O3 is characterized. The branched nanorods of β‐MnO2/α‐Fe2O3 present an excellent lithium‐storage performance. They exhibit a reversible specific capacity of 1028 mAh g?1 at a current density of 1000 mA g?1 up to 200 cycles, much higher than the building blocks alone. Even at 4000 mA g?1, the reversible capacity of the branched nanorods could be kept at 881 mAh g?1. The outstanding performances of the branched nanorods are attributed to the synergistic effect of different components and the hierarchical structure of the composite. The disclosure of the correlation between the electrochemical properties and the structure/component of the nanocomposites, would greatly benefit the rational design of the high‐performance nanocomposites for lithium ion batteries, in the future. 相似文献