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71.
Qing Tan Qing He Weizhong Zhao Zhongzhi Shi E.S. Lee 《Computers & Mathematics with Applications》2011,61(4):1129-1144
In current PC computing environment, the fuzzy clustering method based on perturbation (FCMBP) is failed when dealing with similar matrices whose orders are higher than tens. The reason is that the traversal process adopted in FCMBP is exponential complexity. This paper treated the process of finding fuzzy equivalent matrices with smallest error from an optimization point of view and proposed an improved FCMBP fuzzy clustering method based on evolutionary programming. The method seeks the optimal fuzzy equivalent matrix which is nearest to the given fuzzy similar matrix by evolving a population of candidate solutions over a number of generations. A new population is formed from an existing population through the use of a mutation operator. Better solutions survive into next generation and finally the globally optimal fuzzy equivalent matrix could be obtained or approximately obtained. Compared with FCMBP, the improved method has the following advantages: (1) Traversal searching is avoided by introducing an evolutionary programming based optimization technique. (2) For low-order matrices, the method has much better efficiency in finding the globally optimal fuzzy equivalent matrix. (3) Matrices with hundreds of orders could be managed. The method could quickly get a more accurate solution than that obtained by the transitive closure method and higher precision requirement could be achieved by further iterations. And the method is adaptable for matrices of higher order. (4) The method is robust and not sensitive to parameters. 相似文献
72.
73.
Yunong Zhang Ke Chen Hong-Zhou Tan 《Automatic Control, IEEE Transactions on》2009,54(8):1940-1945
This technical note presents theoretical analysis and simulation results on the performance of a classic gradient neural network (GNN), which was designed originally for constant matrix inversion but is now exploited for time-varying matrix inversion. Compared to the constant matrix-inversion case, the gradient neural network inverting a time-varying matrix could only approximately approach its time-varying theoretical inverse, instead of converging exactly. In other words, the steady-state error between the GNN solution and the theoretical/exact inverse does not vanish to zero. In this technical note, the upper bound of such an error is estimated firstly. The global exponential convergence rate is then analyzed for such a Hopfield-type neural network when approaching the bound error. Computer-simulation results finally substantiate the performance analysis of this gradient neural network exploited to invert online time-varying matrices. 相似文献
74.
Fangfang Zhang Huanshui Zhang Cheng Tan Wei Wang Jinfeng Gao 《International Journal of Control, Automation and Systems》2017,15(6):2507-2515
In this paper, the distributed control of the LQR problem for continuous-time multi-agent systems is considered. Based on the centralized optimal control, we prove that the solution of the algebraic Riccati equation is the maximal solution of the algebraic Riccati inequality. The algebraic relations of the solutions of the algebraic Riccati equations for different weighted matrices are shown and two distributed controllers are designed: the fully distributed one and the interconnected distributed one. They can provide an upper bounds and a lower bounds of the centralized optimal cost function. The optimal closed-loop feedback control systems for the two distributed controllers are also asymptotically stable. Some examples are given to show the correctness of the proposed results. 相似文献
75.
基于Web与组件技术的企业应用系统设计模型 总被引:40,自引:2,他引:38
文章介绍了“Browse-WebServe-DBMS”体系结构的三种模式及相关的程序设计技术[1],提出了一个基于Web与组件技术的企业应用系统软件设计模型,开发了一个应用实例,并统计分析了相关数据,说明了基于Web与组件技术的软件设计方法对于提高组件重用率,缩短开发周期,提高开发效率,提高系统的可维护性等具有明显的优势。 相似文献
76.
Foxpro与Oracle之间数据迁移的实现方法 总被引:6,自引:1,他引:5
文章根据作者在应用系统开发中的实践经验,总结了利用ODBC技术在Foxpro与Oracle之间进行数据交换的三种方法,分析每一种方法的优缺点,并以具体实例作了详细说明。 相似文献
77.
Rachel Edita Oñate Roxas Allan Borra Charibeth Ko Cheng Nathalie Rose Lim Ethel Chuajoy Ong Michelle Wendy Tan 《Language Resources and Evaluation》2008,42(2):183-195
In this paper, we present the building of various language resources for a multi-engine bi-directional English-Filipino Machine
Translation (MT) system. Since linguistics information on Philippine languages are available, but as of yet, the focus has
been on theoretical linguistics and little is done on the computational aspects of these languages, attempts are reported
here on the manual construction of these language resources such as the grammar, lexicon, morphological information, and the
corpora which were literally built from almost non-existent digital forms. Due to the inherent difficulties of manual construction,
we also discuss our experiments on various technologies for automatic extraction of these resources to handle the intricacies
of the Filipino language, designed with the intention of using them for the MT system. To implement the different MT engines
and to ensure the improvement of translation quality, other language tools (such as the morphological analyzer and generator,
and the part of speech tagger) were developed. 相似文献
78.
针对目前智能建筑中几种常见的中央空调机组单元配置及其运行机制,简要分析了采用网络化数字监控技术的空调机组的工作原理,并说明了此类空调配置方案的控制系统结构及其性能特点和应用场合。 相似文献
79.
80.
Sodium-alumina electrolyte tubes were prepared from spray dried precursor powders with additions of 2, 5, 10 and 15 wt % ZrO2 made by the sodium zirconate route. The thermal shock behaviour of ring segments cut from the tubes was examined by quenching into water at 0° C. At the 2% ZrO2 level the dispersed ZrO2 particle size was low, <0.5m, and the tetragonal phase was retained. For higher weight fractions, particle coarsening during the-alumina sintering schedule was extensive and the large particles transformed to monoclinic on cooling. At the 15% ZrO2 level the-alumina had a slightly reduced strength and high resistance to thermal shock and to thermal shock damage, quenching into water from 800° C effecting only a 43% reduction in strength. These observations are consistent with the effects of microcracking in the vicinity of second phase ZrO2 particles. 相似文献