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1.
ONACLASSOFNEWKKMTHEOREMWITHAPPLICATIONSZhangShisheng(张石生),ZhangXian(张宪)(ReceivedMay15,1995)Abstract:Inthispaper,aclassofnewKK...  相似文献   

2.
The limit analysis problem has been considered. The statical and kinematical formulation are summarised, and it is noted that while an existence theorem for the statical problem can obtained by the results of convex analysis, similar theorem for the kinematical problem must be obtained independently. We illustrate the main reasons that lead to a Suquet's relaxed version of the original kinematical problem, and we prove an existence theorem showing that the functional of dissipation is lower semicontinuous. This theorem is compared with an analogous theorem existing in the literature.  相似文献   

3.
In the part 2, theorem 3.1 studied in part 1[15] is proved first. The proof is obtained via a way of changing variables to reduce the original system of differential equations to a form concerning standard systems of equations in the theory of differentiable dynamical systems. Then by using theorem 3.1 together with the preliminary theorem 2.1, the main theorem of this paper announced in part 1 is proved. The definition of admissible perturbation is contained in the appendix of part 2. The meanings of the main theorem is described in the introduction of part 1.  相似文献   

4.
In this paper, some conmments on the proof of Fermat’s last theorem are proposed.The main resuilt is thai the proof proposed by Wong Chiahe is only part of proof for fermat’s last theorem. That is to sqy,the proof is not all-full proof to Fermat’s last theorem.  相似文献   

5.
NEWVERSIONOFKKMTHEOREMINPROBABILISTICMETRICSPACESWITHAPPLICATIONSZhangShisheng(张石生)YeolJeCho(赵烈济)WuXiang(吴鲜)(ReceivedMay7,199...  相似文献   

6.
This paper gives the modified Castigliano’s theorem, which is more convenient and more extensive for applications than the classical Castigliano’s theorem.The modifications to the classical Castigliano ’s theorem are in following two respects, the first respect is that the expression of the partial derivative with respect to the concentrated load p of the complementary energy density in the clasical Castigliano ’s theorem is replaced by the expressions with teh products of the external loads and influence functions, the modification brings us greatest simplicity and greatest convenience for calculations under various loads; the second respect is that the expressions with the products of the inhomogeneous boundary displacements and the influence functions are introduced into the classical Castigliano’s theorem, the modification provides the theoretical fundamental for solving the problems of various boundary conditions.We show also the method of how to apply the modified Castigliano’s theorem to solve the problems of the surface structural mechanics.Finally, as a calculated example of the applications of the modified Castigliano’s theorem we solved the equation of the deflection surface of the rectangular plate with two adjacent edges built-in and other two adjacent edges free.  相似文献   

7.
The averaging method on a semiaxis is justified for systems of difference equations. A theorem on the closeness of the corresponding solutions of the exact and averaged systems on a semiaxis is proved. This theorem is analogous to the second Bogolyubov theorem on the averaging method for systems of difference equations.  相似文献   

8.
Someengineeringproblemscanbeexpressedbysuchasystemoflinearnon_homogeneousdifferentialequationsasL1[u1(q)]=F1(q),L2[u2(q)]=F2(q)+f2[u1(q)],…Ln[un(q)]=Fn(q)+fn[u1(q),u2(q),…,un-1(q)],(1)andtheirinitialandboundaryconditions,whereqisthesetofallargumentsw…  相似文献   

9.
Some new fixed point theorems in probabilistic metric spaces   总被引:21,自引:0,他引:21  
SOMENEWFIXEDPOINTTHEOREMSINPROBABILISTICMETRICSPACESzhuChuan-xi(朱传喜)(MathematiesDivision,Nanchang.University,Nanchang)(Receiv...  相似文献   

10.
IV.ChangingVariablesTheproofofthemaintheoremstatedinSectionIofthepaperwillbecompletedinSectionVI.Now,withthesystem.)giveninSectionill,letuswritesimplyTheexistenceofsuchf(k)followsfromtheproperty(II)ofthesystem.).Theexistenceisunique.Thenbytheproperty(II)o…  相似文献   

11.
德国女数学家Noether E于1918年发表重要论文“不变变分问题”。这篇论文给出两个定理,第一定理涉及经典力学的对称性与守恒量,第二定理涉及广义相对论。Noether第一定理不仅已成为研究经典力学和经典场论中,而且已成为研究量子力学和量子场论中对称性与守恒量关系的基础。本文介绍了Noether的这篇论文和她思想的传播,以及经典力学中的Noether定理。  相似文献   

12.
基于Melan经典的安定理论和von Mises屈服准则,建立了塑性应变强化条件下结构安定的数学模型,根据与时间无关的应力场的特性,对结构中与时间无关的应力场进行了合理的数学变换,将其与载荷变化系数联系起来,推导出与其对应的结构安定极限范围的表达式,给出塑性应变强化模型安定性存在的简化条件.该结论有利于简化应变强化条件下结构的安定分析.  相似文献   

13.
张毅 《力学季刊》2016,37(2):214-224
提出并研究时间尺度上Hamilton系统的Noether对称性与守恒量问题.建立了时间尺度上Hamilton原理,导出了相应的Hamilton正则方程.基于时间尺度上Hamilton作用量在群的无限小变换下的不变性,建立了时间尺度上Hamilton系统的Noether定理.定理的证明分成两步:第一步,在时间不变的无限小变换群下给出证明;第二步,利用时间重新参数化技术得到了一般无限小变换群下的定理.给出了经典和离散两种情况下Hamilton系统的Noether守恒量.文末举例说明结果的应用.  相似文献   

14.
An alternative form is given of the kinematic minimum principle for the rate problem in classical, small displacement plasticity. This study was motivated by the theorem given by G. Maier (1969) based on a quadratic programming approach, but the result is derived from the classical theorem and has a simpler form than Maier's theorem.  相似文献   

15.
1 TheProcessandStatementoftheResultAsadynamicalcounterpartoftheclassicalPoissonlimittheoremfor0_1valuedindependentrandomvariables,aPoissonlimittheoremisprovedbyPitskel[1,2 ]forergodicfiniteMarkovchains,forstronglyergodicnon_homogeneousfiniteMarkovchains.In…  相似文献   

16.
A modified shakedown theorem and its solving technique are presented to involve hydrogen embrittlement of steel into limit and shakedown analysis. Firstly, the shakedown theorem for hydrogen embrittled material is derived from a limited kinematic hardening shakedown theorem and hydrogen enhanced localized plasticity mechanism of hydrogen embrittlement. In the presented theorem, hydrogen’s effect is taken into account by the synergistic action of both strength reduction and stress redistribution. Secondly, a novel solving technique is developed based on the basis reduction method, in which the complicated constraints in the resulting nonlinear mathematical programming are released. At last, three numerical examples are carried out to verify the performance of the proposed method and to reveal hydrogen’s effect on the limit and shakedown load of structure. The numerical results are discussed and compared with those from literatures, which proves the accuracy and high efficiency of the introduced solving technique. It is concluded that the proposed theorem can predict the limit and shakedown load of hydrogen embrittled structure reasonably.  相似文献   

17.
The linear dynamic theory of microstretch thermomagnetoelectroelasticity is studied in this paper.First,a reciprocity relation which involves two processes at different instants is established to form the basis of a uniqueness result and a reciprocal theorem.The proof of the reciprocal theorem avoids both using the Laplace transform and incorporating the initial conditions into the equations of motion.The uniqueness theorem is derived with no definiteness assumption on the elastic constitutive coefficients.Then the continuous dependence theorem is discussed upon two external data systems.Finally,the variational principle of Hamilton type which fully characterizes the solution of the mixed boundary-initial-value problem(mixed problem) is obtained.These theorems lay a solid foundation for further theoretical and numerical studies on microstretch thermomagnetoelectroelastic materials.  相似文献   

18.
IntroductionThefamousAsgeirssonmeanvaluetheoremhasansweredthattheCauchyproblemsareill_posedtotheultra_hyperbolicpartialdifferentialequationsofthesecond_order(Δ2 x-Δ2 y)u=0 . ( 1 )Theresultcanbeusedtoprovethecontinuationofthesolutionsofthisequation ( 1 ) .Soitisi…  相似文献   

19.
诺特(Noether) 定理建立了对称性与守恒定律之间的联系,是现代物理学与力学的基石之一。文中介绍了诺特定理提出的起因、定理的内涵及相关逸闻,说明了固体力学中J 积分、艾西比(Eshelby) 张量与诺特定理的关系。  相似文献   

20.
张毅 《力学学报》2017,(3):693-702
应用分数阶模型可以更准确地描述和研究复杂系统的动力学行为和物理过程,同时Birkhoff力学是Hamilton力学的推广,因此研究分数阶Birkhoff系统动力学具有重要意义.分数阶Noether定理揭示了Noether对称变换与分数阶守恒量之间的内在联系,但是当变换拓展为Noether准对称变换时,该定理的推广遇到了很大的困难.本文基于时间重新参数化方法提出并研究Caputo导数下分数阶Birkhoff系统的Noether准对称性与守恒量.首先,将时间重新参数化方法应用于经典Birkhoff系统的Noether准对称性与守恒量研究,建立了相应的Noether定理;其次,基于分数阶Pfaff作用量分别在时间不变的和一般单参数无限小变换群下的不变性给出分数阶Birkhoff系统的Noether准对称变换的定义和判据,基于Frederico和Torres提出的分数阶守恒量定义,利用时间重新参数化方法建立了分数阶Birkhoff系统的Noether定理,从而揭示了分数阶Birkhoff系统的Noether准对称性与分数阶守恒量之间的内在联系.分数阶Birkhoff系统的Noether对称性定理和经典Birkhoff系统的Noether定理是其特例.最后以分数阶Hojman-Urrutia问题为例说明结果的应用.  相似文献   

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