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1.
本文运用一典型的人工神经网络模型─“反向传播”模型,对高氧化态(Ⅱ─Ⅳ)三核金属簇合物的构型分布进行了分析,得到了较好的分类、预报结果为化合物结构分析提供了新的工具。 相似文献
2.
Wai-Chuen Gan Li Qiu 《Industrial Electronics, IEEE Transactions on》2003,50(2):272-282
It is well known that the system performance for an indirect-field-oriented-control induction motor drive degrades under the variation of rotor resistance and in the presence of external load torque. In this paper, a plug-in robust compensator for speed and position control enhancement of an indirect-field-oriented-control induction machine drive is developed. In the case where a controller for the induction machine already exists or is in operation with satisfactory nominal tracking performance, this plug-in compensator, designed using the H/sub /spl infin// loop-shaping techniques, can be plugged into the existing controller without affecting the already satisfactory nominal tracking performance of the existing closed-loop system but with the capability to improve the system performance under plant parameter variations and in the presence of external disturbances. Simulation and experimental results are given to validate the proposed plug-in robust compensator. 相似文献
3.
In order to investigate the galvanic anodic protection (GAP) of ferrous metals (such as 410, 304 and 316 stainless steels) in acid solutions by doped polyaniline (PANi), separate doped PANi powder-pressed electrodes with different surface areas (the area ratio of the PANi electrode to stainless steel is between 1:1 and 1:2) have been prepared. These were coupled with ferrous metal in the following solutions: 5 M sulphuric acid, 5 M phosphoric acid and industrial phosphoric acid (containing 5 M phosphoric acid and 0.05% chloride ion) to construct a galvanic cell, in which PANi is cathode while ferrous metal is anode. The results indicate that a PANi electrode with sufficient area can provide corrosion protection to stainless steel in these acidic solutions. A pilot scale coupling experiment was carried out. The results indicate that PANi is a promising material as an electrode for the anodic protection of ferrous metals in acidic solutions in industrial situations. 相似文献
4.
介绍了我国紫菜工业在工艺改进、资源开发、综合利用和深度加工等方面的情况,提出了提高产率、降低物耗、增进效益和增加品种的途径。 相似文献
5.
职业素质是劳动者对社会职业了解与适应能力的一种综合体现,主要包括职业修养和职业技能。在高职院校中开展创业教育是我国经济形势发展的需要,对于培养学生的实践能力、创新精神和解决学生的就业压力有着十分重要的意义。广州城建职业学院的创业教育可以从以下三方面着手:一是转变观念,营造氛围;二是传授本领,打好基础;三是开展活动,提高能力,逐步探索出一条适合广州城建职业学院特色高职学生创业教育的新路子。 相似文献
6.
Zhou Shang-Ming Gan John Q. 《Knowledge and Data Engineering, IEEE Transactions on》2009,21(8):1191-1204
In this paper, a method for constructing Takagi-Sugeno (TS) fuzzy system from data is proposed with the objective of preserving TS submodel comprehensibility, in which linguistic modifiers are suggested to characterize the fuzzy sets. A good property held by the proposed linguistic modifiers is that they can broaden the cores of fuzzy sets while contracting the overlaps of adjoining membership functions (MFs) during identification of fuzzy systems from data. As a result, the TS submodels identified tend to dominate the system behaviors by automatically matching the global model (GM) in corresponding subareas, which leads to good TS model interpretability while producing distinguishable input space partitioning. However, the GM accuracy and model interpretability are two conflicting modeling objectives, improving interpretability of fuzzy models generally degrades the GM performance of fuzzy models, and vice versa. Hence, one challenging problem is how to construct a TS fuzzy model with not only good global performance but also good submodel interpretability. In order to achieve a good tradeoff between GM performance and submodel interpretability, a regularization learning algorithm is presented in which the GM objective function is combined with a local model objective function defined in terms of an extended index of fuzziness of identified MFs. Moreover, a parsimonious rule base is obtained by adopting a QR decomposition method to select the important fuzzy rules and reduce the redundant ones. Experimental studies have shown that the TS models identified by the suggested method possess good submodel interpretability and satisfactory GM performance with parsimonious rule bases. 相似文献
7.
8.
控制系统校正环节优化设计的计算机辅助分析 总被引:2,自引:0,他引:2
结合共轭梯度法,借助于MATLAB软件,提出一种控制系统校正环节优化设计的新方法.该方法利用了MAT-LAB软件中的符号数学工具箱、控制系统工具箱和优化设计工具箱,使设计简单、快捷,提高了编程效率. 相似文献
9.
用正电子湮没研究含砷α黄铜的脱锌机制 总被引:3,自引:0,他引:3
分别测量了含0.00、0.01、0.03、0.05、007、0.10wt%As的68wt%Cu-Zn合金在1%CuCl2水溶液中脱锌后的正电子寿命谱。讨论了黄铜脱锌及砷抑制脱锌的空位体扩散机制。 相似文献