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K-S 函数与模函数法的统一 被引量:10
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作者 隋允康 于新 《大连理工大学学报》 CAS CSCD 北大核心 1998年第5期502-505,共4页
提出了极小极大(minimax)问题统一解法的变换求和反演表达.论证了K-S函数法、广义指数罚函数法和模优化法都可以统一在这一表达之中,并且提出了一种新函数S-Y函数.数值结果表明K-S函数法、模优化法和S-Y函数法... 提出了极小极大(minimax)问题统一解法的变换求和反演表达.论证了K-S函数法、广义指数罚函数法和模优化法都可以统一在这一表达之中,并且提出了一种新函数S-Y函数.数值结果表明K-S函数法、模优化法和S-Y函数法具有相同的数值规律,其统一解法是合理的. 展开更多
关键词 最佳化 K-S函数 统一解 模函数法
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港区水域通航环境综合评价模型研究 被引量:13
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作者 陈影 翁建军 郭国平 《武汉理工大学学报(交通科学与工程版)》 2012年第3期571-574,共4页
针对港区水域通航环境危险度评价指标的权重计算和综合评价问题,运用主客观组合赋权法和距离函数建模法并借助MATLAB工具对多个港区通航环境危险度评价指标的权重进行计算并进行了综合评价.模型应用分析结果表明,该模型能够快速地对多... 针对港区水域通航环境危险度评价指标的权重计算和综合评价问题,运用主客观组合赋权法和距离函数建模法并借助MATLAB工具对多个港区通航环境危险度评价指标的权重进行计算并进行了综合评价.模型应用分析结果表明,该模型能够快速地对多个港口的通航环境做出综合评价,并且评价结果具有稳定性和可靠性. 展开更多
关键词 通航环境 综合评价 主客观组合赋权 距离函数
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数字控制式LLC谐振变换器建模分析与验证 被引量:1
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作者 张雷 邱亚峰 刘一希 《电子产品世界》 2015年第7期59-62,共4页
针对半桥LLC谐振变换器的建模及其验证展开分析,同时分析了数字控制对系统稳定性造成的影响,并给出采用数字控制时系统稳定性的解决方案。首先,通过扩展函数描述法得到传统的模拟域数学模型,并在Saber中搭建仿真模型,利用小信号分析法... 针对半桥LLC谐振变换器的建模及其验证展开分析,同时分析了数字控制对系统稳定性造成的影响,并给出采用数字控制时系统稳定性的解决方案。首先,通过扩展函数描述法得到传统的模拟域数学模型,并在Saber中搭建仿真模型,利用小信号分析法验证该数学模型的准确性,从而得出得到的系统数学模型具有参考性,由此提供了环路设计的基础;其次,采用数字控制,考虑到其离散特性,分析了数字控制对系统稳定性的影响,并通过Matlab仿真验证了该理论的正确性,最终设计出性能良好的数字PID补偿器;最后,针对实际应用场合,搭建实验平台,进行相关实验验证。 展开更多
关键词 数字控制 扩展函数描述 系统稳定性 LLC谐振变换器 PID补偿器
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New Structural Self-Organizing Fuzzy CMAC with Basis Functions
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作者 何超 徐立新 +1 位作者 董宁 张宇河 《Journal of Beijing Institute of Technology》 EI CAS 2001年第3期298-305,共8页
To improve the nonlinear approximating ability of cerebellar model articulation controller(CMAC), by introducing the Gauss basis functions and the similarity measure based addressing scheme, a new kind of fuzzy CMAC... To improve the nonlinear approximating ability of cerebellar model articulation controller(CMAC), by introducing the Gauss basis functions and the similarity measure based addressing scheme, a new kind of fuzzy CMAC with Gauss basis functions(GFCMAC) was presented. Moreover, based upon the improvement of the self organizing feature map algorithm of Kohonen, the structural self organizing algorithm for GFCMAC(SOGFCMAC) was proposed. Simulation results show that adopting the Gauss basis functions and fuzzy techniques can remarkably improve the nonlinear approximating capacity of CMAC. Compared with the traditional CMAC,CMAC with general basis functions and fuzzy CMAC(FCMAC), SOGFCMAC has the obvious advantages in the aspects of the convergent speed, approximating accuracy and structural self organizing. 展开更多
关键词 CMAC FUZZY basis functions self organizing algorithm neural networks
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Research on optimization of valve open time of the launch barge's ballast tanks
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作者 孙承猛 纪卓尚 《Journal of Marine Science and Application》 2009年第1期1-6,共6页
Launch barge is an effective tool for transporting ship segments from one place to another in shipyards. During shifting of segments onto a barge, the slideway on the barge's deck must be adjusted to maintain the sam... Launch barge is an effective tool for transporting ship segments from one place to another in shipyards. During shifting of segments onto a barge, the slideway on the barge's deck must be adjusted to maintain the same level as the wharf and also the barge must be kept level by adjusting the water in the ballast tanks. When to open the adjusting valves is an important factor influencing the barge's trim during the water-adjustment process. Because these adjustments are complex a mathematical model was formulated,after analyzing the characteristics of the process of moving the segments onto the barges deck, and considering the effects of this movement's speed and variations in tidal levels during the move. Then the model was solved by the penalty function method, the grid method, and improved simulated annealing, respectively. The best optimization model and its corresponding solution were then determined. Finally, it was proven that the model and the method adopted are correct and suitable, by calculating and analysing an example. 展开更多
关键词 launch barge STOWAGE penalty function method simulated annealing method grid method
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Simulation and Design of Fuzzy Sliding-mode Controller for Ship Heading-tracking 被引量:3
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作者 袁雷 吴汉松 《Journal of Marine Science and Application》 2011年第1期76-81,共6页
In considering the characteristic of a rudder,the maneuvers of a ship were described by an unmatched uncertain nonlinear mathematic model with unknown virtual control coefficient and parameter uncertainties.In order t... In considering the characteristic of a rudder,the maneuvers of a ship were described by an unmatched uncertain nonlinear mathematic model with unknown virtual control coefficient and parameter uncertainties.In order to solve the uncertainties in the ship heading control,specifically the controller singular and paramount re-estimation problem,a new multiple sliding-mode adaptive fuzzy control algorithm was proposed by combining Nussbaum gain technology,the approximation property of fuzzy logic systems,and a multiple sliding-mode control algorithm.Based on the Lyapunov function,it was proven in theory that the controller made all signals in the nonlinear system of unmatched uncertain ship motion uniformly bounded,with tracking errors converging to zero.Simulation results show that the demonstrated controller design can track a desired course fast and accurately.It also exhibits strong robustness peculiarity in relation to system uncertainties and disturbances. 展开更多
关键词 ship autopilot nonlinear system unmatched uncertainty multiple sliding mode control fuzzy control
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A B-spline active contour model based on finite element method 被引量:1
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作者 成思源 《Journal of Chongqing University》 CAS 2003年第1期62-65,共4页
A B-spline active contour model based on finite element method is presented, into which the advantages of a B-spline active contour attributing to its fewer parameters and its smoothness is built accompanied with redu... A B-spline active contour model based on finite element method is presented, into which the advantages of a B-spline active contour attributing to its fewer parameters and its smoothness is built accompanied with reduced computational complexity and better numerical stability resulted from the finite element method. In this model, a cubic B-spline segment is taken as an element, and the finite element method is adopted to solve the energy minimization problem of the B-spline active contour, thus to implement image segmentation. Experiment results verify that this method is efficient for B-spline active contour, which attains stable, accurate and faster convergence. 展开更多
关键词 active contour mode B-SPLINE finite element method
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Research on Modified Shifting Balance Genetic Algorithms 被引量:1
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作者 MA Hong-mei GONG Dun-wei 《Journal of China University of Mining and Technology》 EI 2007年第2期188-192,共5页
The increasing overlap of core and colony populations during the anaphase of evolution may limit the performance of shifting balance genetic algorithms. To decrease such overlapping,so as to increase the local search ... The increasing overlap of core and colony populations during the anaphase of evolution may limit the performance of shifting balance genetic algorithms. To decrease such overlapping,so as to increase the local search capability of the core population,the sub-space method was used to generate uniformly distributed initial colony populations over the decision variable space. The core population was also dynamically divided,making simultaneous searching in several local spaces possible. The algorithm proposed in this paper was compared to the original one by searching for the optimum of a complicated multi-modal function. The results indicate that the solutions obtained by the modified algorithm are better than those of the original algorithm. 展开更多
关键词 genetic algorithms shifting balance genetic algorithms small spaces dynamic partition multi-modal function
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Chinese Fuzzy Ontology Mapping Based on Support Vector Machine 被引量:2
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作者 Liu Jie Ma Yun +1 位作者 Tang Shiping Lu Peng 《China Communications》 SCIE CSCD 2012年第3期134-144,共11页
Taking into account that fuzzy ontology mapping has wide application and cannot be dealt with in many fields at present,a Chinese fuzzy ontology model and a method for Chinese fuzzy ontology mapping are proposed.The m... Taking into account that fuzzy ontology mapping has wide application and cannot be dealt with in many fields at present,a Chinese fuzzy ontology model and a method for Chinese fuzzy ontology mapping are proposed.The mapping discovery between two ontologies is achieved by computing the similarity between the concepts of two ontologies.Every concept consists of four features of concept name,property,instance and structure.First,the algorithms of calculating four individual similarities corresponding to the four features are given.Secondly,the similarity vectors consisting of four weighted individual similarities are built,and the weights are the linear function of harmony and reliability.The similarity vector is used to represent the similarity relation between two concepts which belong to different fuzzy ontolgoies.Lastly,Support Vector Machine(SVM) is used to get the mapping concept pairs by the similarity vectors.Experiment results are satisfactory. 展开更多
关键词 fuzzy ontology mapping similarity ag-gregation fuzzy knowledge representation SVM
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Global Convergence of a New Restarting Conjugate Gradient Method for Nonlinear Optimizations 被引量:1
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作者 SUN Qing-ying(Department of Applied Mathematics, Dalian University of Technology, Dalian 116024, China Department of Applied Mathematics, University of Petroleum , Dongying 257061, China) 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第2期154-162,共9页
Conjugate gradient optimization algorithms depend on the search directions with different choices for the parameters in the search directions. In this note, by combining the nice numerical performance of PR and HS met... Conjugate gradient optimization algorithms depend on the search directions with different choices for the parameters in the search directions. In this note, by combining the nice numerical performance of PR and HS methods with the global convergence property of the class of conjugate gradient methods presented by HU and STOREY(1991), a class of new restarting conjugate gradient methods is presented. Global convergences of the new method with two kinds of common line searches, are proved. Firstly, it is shown that, using reverse modulus of continuity function and forcing function, the new method for solving unconstrained optimization can work for a continously dif ferentiable function with Curry-Altman's step size rule and a bounded level set. Secondly, by using comparing technique, some general convergence properties of the new method with other kind of step size rule are established. Numerical experiments show that the new method is efficient by comparing with FR conjugate gradient method. 展开更多
关键词 nonlinear programming restarting conjugate gradient method forcing function reverse modulus of continuity function CONVERGENCE
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