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61.
弹塑性有限变形的拟流动理论 总被引:13,自引:0,他引:13
本文提出一种弹塑性有限变形的拟流动理论。该理论从正交性法则出发,通过引入“拟弹性模量”和模量衰减函数并改进应变率的弹塑性分解,实现了由有限变形Prandtl-Reuss流动理论(J2F)向基于非正交法则的率形式形变理论(J2D)的合理的光滑过渡;并适用于初始及后继各向异性变形分析。在特殊条件下,可退化为J2F、J2D理论以及由任意各向异性屈服函数描述的流动理论。将该理论用于韧性金属平面应力/应变拉伸失稳与变形局部化的有限元模拟,并与理论分析及实验结果相比较,表明了本文理论的正确性。 相似文献
62.
YiHua Deng 《Mathematische Nachrichten》2015,288(10):1122-1126
In this note, we get a necessary and sufficient condition such that the scalar curvature of generalized m‐quasi‐Einstein manifold with is constant. In particular, we discuss a class of generalized quasi‐Einstein manifolds which are more general than ‐quasi‐Einstein manifolds and prove that these manifolds with dimension four are either Einstein or locally conformally flat under some suitable conditions. 相似文献
63.
In this paper, a new iterative scheme by hybrid method is constructed. Strong convergence of the scheme to a common element of the set of common fixed points of finite family of relatively quasi-nonexpansive mappings and set of common solutions of a system of equilibrium problems in a uniformly convex and uniformly smooth real Banach space is proved using the properties of generalized f-projection operator. Our results extend important recent results. 相似文献
64.
以双分数次Brown运动为例,本文对一类具有较弱性质的连续Gauss过程x证明其q变差2n-1∑i=0 |x((i+1)2-n)∧t-X(i2-n)∧t|q拟必然收敛到0.对双参数情形我们也给出相应的结果. 相似文献
65.
Tarek Sayed Ahmed 《Mathematical Logic Quarterly》2011,57(4):384-394
Using games, as introduced by Hirsch and Hodkinson in algebraic logic, we give a recursive axiomatization of the class RQPEA α of representable quasi‐polyadic equality algebras of any dimension α. Following Sain and Thompson in modifying Andréka’s methods of splitting, to adapt the quasi‐polyadic equality case, we show that if Σ is a set of equations axiomatizing RPEA n for $2< n <\omegaUsing games, as introduced by Hirsch and Hodkinson in algebraic logic, we give a recursive axiomatization of the class RQPEA α of representable quasi‐polyadic equality algebras of any dimension α. Following Sain and Thompson in modifying Andréka’s methods of splitting, to adapt the quasi‐polyadic equality case, we show that if Σ is a set of equations axiomatizing RPEA n for $2< n <\omega$ and $l< n,$ $k < n$, k′ < ω are natural numbers, then Σ contains infinitely equations in which ? occurs, one of + or · occurs, a diagonal or a permutation with index l occurs, more than k cylindrifications and more than k′ variables occur. © 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim 相似文献
66.
Messaoud Boulbrachene 《Mathematical Methods in the Applied Sciences》2019,42(16):5305-5316
In this paper, we extend the approach developed by the author for the standard finite element method in the L∞‐norm of the noncoercive variational inequalities (VI) (Numer Funct Anal Optim.2015;36:1107‐1121.) to impulse control quasi‐variational inequality (QVI). We derive the optimal error estimate, combining the so‐called Bensoussan‐Lions Algorithm and the concept of subsolutions for VIs. 相似文献
67.
Hicham Benaissa El‐Hassan Benkhira Rachid Fakhar Abdelhadi Hachlaf 《Mathematical Methods in the Applied Sciences》2019,42(4):1292-1311
We consider here a mathematical model describing the bilateral frictional contact between a thermo‐piezoelectric body and a thermally conductive foundation. We model the behavior of the material with a linear thermo‐electro‐elastic constitutive law. The process is assumed to be quasistatic and the contact is modeled with a nonlocal version of Coulomb's dry friction law, in which the frictional heat generated in the process, is taken into account. We drive a variational formulation of the problem and establish the existence of its weak solution. 相似文献
68.
Liya Liu Xiaolong Qin Jen‐Chih Yao 《Mathematical Methods in the Applied Sciences》2019,42(18):7367-7380
The purpose of this paper is to introduce a hybrid descent algorithm for finding a common point in fixed‐point sets of quasi‐nonexpansive mappings and solution sets of variational inequality problems. In the framework of Hilbert spaces, the strong convergence of the hybrid descent algorithm is established. Numerical experiments for the bandwidth allocation, which demonstrate the effectiveness, performance, and convergence of the proposed algorithm, are provided. 相似文献
69.
Lorenzo Carlucci 《Mathematical Logic Quarterly》2005,51(4):342-350
We define a direct translation from finite rooted trees to finite natural functions which shows that the Worm Principle introduced by Lev Beklemishev is equivalent to a very slight variant of the well‐known Kirby‐Paris' Hydra Game. We further show that the elements in a reduction sequence of the Worm Principle determine a bad sequence in the well‐quasi‐ordering of finite sequences of natural numbers with respect to Friedman's gapembeddability. A characterization of gap‐embeddability in terms of provability logic due to Lev Beklemishev is also presented. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
70.