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The results are helpful for the optimal design of the generator and the optimal control of excitingwinding.


Different topics are involved in the optimal design of coatingbased systems.


Three flexibility problems, viz., the flexibility of a technical system of given structure, structural flexibility of a technical system, and the optimal design guaranteeing the flexibility of a technical system, are studied.


The optimal design of the real complex system (whose nature is stochastic) is determined from a mathematic model of an ideal complex system.


Using this method makes it possible to substantiate the choice of the optimal design of contact units in cascade pneumatic classifiers for various technological conditions.

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 This artical deals with the optimal design of spectral estimates for stationary wave processes. The quality of spectral estimates is measured with the relative mean square error: Ine method lor choosing the lag numberm minimizing the relative mean square error of spectral estimates, which is presented by Grenander et al and Priestley, is applied to windwave spectrum estimates. In this optimal design of spectral estimates the lag number m depends on the spectralbandwidth parameter:,therefore,... This artical deals with the optimal design of spectral estimates for stationary wave processes. The quality of spectral estimates is measured with the relative mean square error: Ine method lor choosing the lag numberm minimizing the relative mean square error of spectral estimates, which is presented by Grenander et al and Priestley, is applied to windwave spectrum estimates. In this optimal design of spectral estimates the lag number m depends on the spectralbandwidth parameter:,therefore, the spectral bandwidthparameter Bf(ω) (or at least Bfs(ω) =minBf(ω)) must be known before spectra are estimated in order to get optimal estimates. On the basis of the similarity of spectra, it is considered to be reasonable that the spectral bandwidth parameterBf(ω) is estimated using Neumann spectra; Bf(ω)/(ω)*=K/{  (p + 1)p(2p+q+1)p/K9 + p2/K2q}t/2 (ω is spectral peak frequency). Then, the relation among the relative mean square error M of spectral estimates, the significant wave period Tsof wave surface records, and the lag number m can be obtained using the empirical formulae ω*=2π/105Ts proposed by TOBA.In this paper, three optimal designs for estimating windwave spectra: Bartlett, Rectangular, and Tukey estimates are presented. Plot of the relation between nondimensional spectrum bandwidth parameter and nondimensional frequency in the forms of Neumann spectra, plot of the relation among the relative mean square error of spectral estimates, the significant wave period of wave surface records, and the lag number m in the three estimates, and plots of comparison of the optimal designs of spectral estimates made by the three methods are given. The effect of application for the optimal design is discussed.  本文基于谱理论,提出了使谱估计的相对均方误差为最小的确定滞后数m的理论依据;建立了最优估计中相对均方误差M、滞后数m和波面记录有效波周期之间的关系。并以实测波面记录,分别以Bartlett估计、矩形估计和Tukey估计作出的谱讨论了最优设计的使用效果。  In this paper, based on the wave data of observation for many years obtained in the coastal areas of the Beibu Gulf,the annual extreme wave hights for the directions of the dominant wave and secondary wave in different sea areas are respectively taken as sample data.Using the PⅢtype method and a frequency analysis method for measuring shortterm wave data, the design wave heights in the different areas for various recurrence intervals are respectively estimated.Constant as the sample data and the methods of... In this paper, based on the wave data of observation for many years obtained in the coastal areas of the Beibu Gulf,the annual extreme wave hights for the directions of the dominant wave and secondary wave in different sea areas are respectively taken as sample data.Using the PⅢtype method and a frequency analysis method for measuring shortterm wave data, the design wave heights in the different areas for various recurrence intervals are respectively estimated.Constant as the sample data and the methods of estimation are, the results of estimation every time are different from each other and their discrepancy is even quite large. Using Kolmosoroff's method of the fit degree to check the results obtained, the optimal design waves in the coastal areas can be accurately decided for various recurrence intervals.  本文基于北部湾沿岸海区多年的实测资料，于不同海区主浪向和次主浪向分别取年极值波高为样本资料．采用Ｐ－Ⅲ型和短期测波资料频率分析方法，分别估算了各海区不同重现期的设计波高，并依据式（１）计算出相应的平均周期。尽管样本资料和估算方法不变，但每次估算的结果互不相同，其差异甚至很大．利用Ｋｏｌｍｏｇｏｒｏｆｆ等适合度方法检验所得的结果，能够准确地判断出沿岸各海区不同重现期的最佳设计波浪。  Minimum offshore platform is the main style of engineering structure of oil and gas exploitation in marginal offshore.For minimum offshore platform has simple structure form,it will have larger response when acting vibration force.Dynamic optimum design method can optimize the platform structure form in order to reduce the response of platform under vibration force.In this paper,author utilized the ANSYS FEM software to give a dynamic optimum design of the JZ202NW minimum offshore platform when... Minimum offshore platform is the main style of engineering structure of oil and gas exploitation in marginal offshore.For minimum offshore platform has simple structure form,it will have larger response when acting vibration force.Dynamic optimum design method can optimize the platform structure form in order to reduce the response of platform under vibration force.In this paper,author utilized the ANSYS FEM software to give a dynamic optimum design of the JZ202NW minimum offshore platform when acting iceinduced vibration force.The optimal design result indicated that,the dynamic optimum design can efficiently control the vibration response.This method can be referenced by designer.  简易平台是边际油田开发的主要结构形式,由于平台结构形式简单,受到动力荷载作用响应比较大。采用动态设计可以合理优化平台结构形式,达到降低平台动力响应的效果。文中以JZ202NW简易平台为原型,运用AN SY S有限元分析软件对其进行冰激振动下的动态优化设计。结果表明,动态设计减振效果明显,可供设计人员参考。   << 更多相关文摘 
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