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151.
D. P. Aleksandrov 《Mechanics of Composite Materials》2005,41(6):541-552
The mechanical state of a press-powder filler for pyroautomatics system units of aerospace equipment during their long-term
storage is investigated. With the use of the endochronic approach, the rheological properties of a dispersedly reinforced
composite are simulated based on the conceptions of linear and nonlinear creep. Analytical expressions of constitutive relations
of creep and strength for the composites are obtained.
__________
Translated from Mekhanika Kompozitnykh Materialov, Vol. 41, No. 6, pp. 803–818, November–December, 2005. 相似文献
152.
对近年来国内外在元件疲劳可靠性估算方法方面所做的研究作了系统的回顾和讨论,按安全余量方程将其分为三类:累积损伤模型、乘余强度模型和疲劳寿命模型,并对这三种模型的特点及局限性作了分析论述,对元件疲劳可靠性分析的发展趋势作了讨论。 相似文献
153.
在Ray的论文[Onproduct of fuzzy subgroups105(1999)181—183]中,作者给出了模糊子群直积在min下的一些性质。在本文中我们将给出更多关于模糊子群直积的性质,并推广到模糊子环上;最后讨论了模糊子群的直积在t-模下的一些性质。 相似文献
154.
含分层损伤复合材料层合板的压缩强度研究 总被引:5,自引:0,他引:5
给出了基于一阶剪切变形理论的含分层损伤层合板有限元分析模型,将含分层损伤层合板在压缩载荷作用下的强度破坏分析和屈曲破坏分析统一起来,先区分其破坏形式,然后再进行具体破坏分析.在屈曲特性分析中考虑了铺层强度破坏引起的刚度折减的影响.数值结果表明, 该文给出的方法和结论对含分层损伤复合材料层合板的设计更具参考价值. 相似文献
155.
Christophe Lacave 《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2009,26(4):1121-1148
In this work we study the asymptotic behavior of solutions of the incompressible two dimensional Euler equations in the exterior of a single smooth obstacle when the obstacle becomes very thin tending to a curve. We extend results by Iftimie, Lopes Filho and Nussenzveig Lopes, obtained in the context of an obstacle tending to a point, see [D. Iftimie, M.C. Lopes Filho, H.J. Nussenzveig Lopes, Two dimensional incompressible ideal flow around a small obstacle, Comm. Partial Differential Equations 28 (1–2) (2003) 349–379]. 相似文献
156.
Bert O. Baumgaertner Rebecca C. Tyson Stephen M. Krone 《The Journal of mathematical sociology》2016,40(4):207-218
Opinions are rarely binary; they can be held with different degrees of conviction, and this expanded attitude spectrum can affect the influence one opinion has on others. Our goal is to understand how different aspects of influence lead to recognizable spatio-temporal patterns of opinions and their strengths. To do this, we introduce a stochastic spatial agent-based model of opinion dynamics that includes a spectrum of opinion strengths and various possible rules for how the opinion strength of one individual affects the influence that this individual has on others. Through simulations, we find that even a small amount of amplification of opinion strength through interaction with like-minded neighbors can tip the scales in favor of polarization and deadlock. 相似文献
157.
柯尔莫哥洛夫检验在混凝土强度检测中的应用 总被引:1,自引:0,他引:1
回弹法是检测混凝土强度的一种常用方法,回弹法的测量精度依赖于数据本身的真实性。本文提出了一种利用柯尔莫哥洛夫检验控制测量数据误差的方法。 相似文献
158.
C. Soutis 《Mechanics of Composite Materials》2007,43(1):51-58
Cohesive-zone models have been successfully applied to predicting the damage from notches in engineering materials loaded
intension. They have also been used to determine the growth of fibre microbuckling from a hole in a composite laminate under
compression. The usual strategy is to replace the in elastic deformation associated with plasticity or microbuckling with
a line crack and to assume some form of stress-displacement bridging law across the crack faces. This paper examines recent
published experimental data for notched glass-fibre epoxy/honey comb sand wich panels loaded in uniaxial compression. A plastic
fibre kinking analysis and a linear softening cohesive-zone model are used for the prediction of the unnotched and open-hole
compressive strength and the theoretical results are found to be in a good agreement with experimental data.
Russian translation published in Mekhanika Kompozitnykh Materialov, Vol. 43, No. 1, pp. 73–84, January–February, 2007. 相似文献
159.
The paper presents a theoretical-numerical hybrid method for determining the stresses distribution in composite laminates
containing a circular hole and subjected to uniaxial tensile loading. The method is based upon an appropriate corrective function
allowing a simple and rapid evaluation of stress distributions in a generic plate of finite width with a hole based on the
theoretical stresses distribution in an infinite plate with the same hole geometry and material. In order to verify the accuracy
of the method proposed, various numerical and experimental tests have been performed by considering different laminate lay-ups;
in particular, the experimental results have shown that a combined use of the method proposed and the well-know point-stress
criterion leads to reliable strength predictions for GFRP or CFRP laminates with a circular hole.
Russian translation published in Mekhanika Kompozitnykh Materialov, Vol. 43, No. 4, pp. 531–570, July–August, 2007. 相似文献
160.
关于Fuzzy Drazin子半群 总被引:2,自引:0,他引:2
本文引进了FuzzyDrazin子半群的概念,并讨论了它们的一些代数性质,改进并推广了[5]、[6]、[8]、[10]及[11]中的许多重要结果 相似文献