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In this paper, we study the lattice structure of some fuzzy algebraic systems such as (G-)fuzzy groups, some fuzzy ordered algebras and fuzzy hyperstructures. We prove that under suitable conditions, these structures form a distributive or modular lattice. This research partially is supported by the “ Fuzzy Systems and its Applications Center of Excelence, Shahid Bahonar University of Kerman, Iran”.  相似文献   
3.
This paper studies a Kansas Department of Transportation welded plate girder bridge that developed fatigue cracks at small web gaps close to the girder top flange. Repair had been previously performed by softening the connection plate end with a slot retrofit, but cracks were recently found to have reinitiated at some of the repaired details and are again propagating. A comprehensive finite-element method study was performed to investigate the cracking behavior observed in the bridge and to recommend appropriate measures for future bridge retrofit. The analytical results show that stresses developed at the top flange web gaps could exceed yielding under the loading of an HS15 fatigue truck. The current slot repair used in the bridge was found to have introduced higher magnitude fatigue stresses in the web gap. To achieve a permanent repair of the bridge, it is recommended that a welded connection plate to flange attachment be used during future bridge retrofit. The web gap details should be able to withstand unlimited number of load cycles once this additional repair is performed.  相似文献   
4.
In this paper, an adaptive line spectral pair filter is derived from an adaptive lattice filter. A least-mean-square(LMS) type adaptive algorithm used to calculate directly the line spectral pair(LSP) coefficients on a stage-by-stage basis is presented. Experimental results show that the algorithm has higher convergence rate and lower misadjustment as compared with the other algorithms. The LSP coefficients calculated by the algorithm have been used to carry out speech linear predictive synthesis, resulting in better results than PARCOR coefficients.  相似文献   
5.
The compositions (1 −x)Ag2SO4−(x)BaSO4, wherex=0·01 to 0·6, were prepared by slow cooling of the melt. The extent of the solid solubility of Ba2+ in Ag2SO4 was determined by X-ray powder diffraction and scanning electron microscopy. The bulk conductivity of each sample was obtained using a detailed impedance analysis. The partial substitution of Ba2+ results in the enhancement of conductivity in compliance with the classical aliovalent doping theory. A simplistic model based on lattice distortion (expansion) due to partial substitution of Ag+ by the bigger Ba2+ has been considered to explain enhanced conductivity. Beyond solid-solubility limit (5·27 mole%) the BaSO4-dispersed Ag2SO4 conductivity follows the usual trend seen in binary systems. An increase in conductivity in this case is discussed in the light of interfacial reactions and surface defect chemistry. The maximum conductivity in 20 mole% BaSO4 dispersed Ag2SO4 is due to percolation threshold.  相似文献   
6.
几何造型是计算机图形学的重要研究内容,CAD/CAM的核心技术,现行的许多造型系统仅限于造型二次曲面及旋转曲面,没有自由曲面造型能力,本文研究的自由畸变为法,很容易扩展这些系统的自由曲面造型功能,该方法已成功地用于扩展MOVIE.BYU系统的自由曲面造型功能。  相似文献   
7.
预应力混凝土箱梁主要裂缝成因和防治措施的探讨   总被引:2,自引:0,他引:2  
预应力混凝土连续箱梁的裂缝问题一直以来倍受桥梁界专家及技术人员的关注。本文通过对预应力混凝土连续箱梁主要裂缝产生的原因进行了浅析,并提出了相应的防治的措施。  相似文献   
8.
Nucleation kinetics during the growth of InxGa1−xN on a GaN substrate have been studied. The behavior of nonequilibrium between the InxGa1−xN and the GaN substrate has been analyzed, and hence, the expression derived for the stress-induced supercooling/superheating has been numerically evaluated. The maximum amount of stress-induced supercooling is found to be 1.017 K at x=0.12. These values are incorporated in the classical heterogeneous nucleation theory. Using the regular solution model, the interfacial tension between the nucleus and substrate and, hence, the interfacial tension between nucleus and mother phase and thermodynamical potential of the compounds have been calculated. The amount of driving force available for the nucleation has been determined for different compositions and degrees of supercooling. It has been shown that the value of the interaction parameter of InN-GaN plays a dominant role in nucleation and growth kinetics of InxGa1−xN on a GaN substrate. These values have been used to evaluate the nucleation parameters. It is shown that the nucleation barrier for the formation of a InxGa1−xN nucleus on a GaN substrate is minimum in the range of x=0.12 to x=0.17, and it has been qualitatively proved that good quality InxGa1−xN on GaN can be grown only in the range 0<x≤0.2.  相似文献   
9.
以上海市沪闵路高架道路二期工程SW匝道曲线箱梁设计为例 ,对曲线梁的内力特点及调整方法作了初步探索。  相似文献   
10.
MIMO系统的自适应均衡技术研究   总被引:1,自引:1,他引:0  
研究了用于MIMO系统的自适应均衡的几种算法,比较了最小均方算法(LMS)、递归最小二乘算法(RLS)、判决反馈算法(DFE)、格型梯度自适应均衡算法(GALE)和格型最小二乘自适应均衡算法(LSALE)。文章的最后给出了仿真结果及结论。  相似文献   
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