共查询到20条相似文献,搜索用时 320 毫秒
1.
2.
弱s-置换性传递的有限群 总被引:1,自引:0,他引:1
群G被称为弱s-置换性传递的群,对于它的子群H和K,若H在K中弱s-置换,K在G中弱s-置换,则H在G中弱s-置换.本文给出弱s-置换性、弱s-补性传递的可解群的结构以及每一子群在G中弱s-置换、弱s-补的群的结构. 相似文献
3.
本文证明Banach空间中无界域上一类弱序列连续和1-集弱压缩算子的若干新不动点定理.我们引入原点处弱半闭算子,得到该算子的若干不动点定理.进而将著名的Leray-Schauder不动点定理、Altman定理、Roth定理和Petryshyn定理推广到弱序列连续算子和1-集弱压缩算子以及原点处弱半闭算子的情形.本文的主要结果依赖于非紧性弱原子测度的有关条件. 相似文献
4.
林鸿钊 《纯粹数学与应用数学》2011,27(5):650-655
为了进一步研究Banach空间中集合的紧致性,受极限集与极限算子定义的启发,给出了弱极限集与弱极限算子的定义,得到了它们的等价刻画,利用空间结构与算子理想的互动关系证明了弱极限算子全体是Pietsch意义下的闭满射算子理想. 相似文献
5.
本文首先在一般的赋范线性空间中研究了集值映射F;X→Y的平衡点的存在性问题,证明了包含问题O∈F(X)的三个可解性定理.然后在无穷维空间中研究了弱相依锥Tkσ(x)的直接像,弱相依导数DσF(x,y)的一个链式法则以及偏y弱导数DyσF(x,y)的弱Lip连续性.最后,作为应用,给出并证明了用弱相依导数DσF(x,y)及弱P导数PσF(x,y)判定无穷维 相似文献
6.
本文在有单位元的结合环上,研究模范畴的完全子范畴上的弱反射,得出特殊模族上包含性弱反射存在的一个充分条件,从而对模性质的内在本质有着更深入的刻画. 相似文献
7.
本文利用微分方程的指数型三分性给出了弱概周期微分方程的弱概周期解的存在性定理,并讨论了弱概周期微分方程的一些性质,从而改进了文献[2—7]中的一些结果. 相似文献
8.
9.
在弱Hopf群余代数情形中,讨论了一簇从弱Doi-Hopf群模范畴到某个代数上的模范畴忘却函子的可分性,诱导出弱Doi-Hopf群模数据的正规化积分概念,证明了正规化积分存在性是忘却函子可分的判别准则.所得结果在弱量子Yetter-Drinfel'd群模范畴及弱相对Hopf群模范畴中有应用价值. 相似文献
10.
研究了具有任意多个局中人的非合作多目标博弈(多目标大博弈).基于一般非合作博弈中的Berge均衡概念,定义多目标大博弈中的弱Pareto-Berge均衡.进一步推广了截口定理,得到新的截口定理,并且利用这个新的截口定理证明多目标大博弈中弱Pareto-Berge均衡的存在性.多目标大博弈中弱Pareto-Nash均衡的存在性结论可作为弱Pareto-Berge均衡存在性的特例给出. 相似文献
11.
V.V. Kurta 《Applicable analysis》2013,92(1-4):301-324
It is well known that a Monotonicity Condition and a Coerciveness Condition principally lie in the basis of most results of the Theory of PDE's. The necessity of these important assumptions for the validity of a comparison principle and analogues of the Phragmen-Lindelöf theorem for solutions of quasilinear parabolic inequalities is discussed in the paper. In the first part of the work we introduce a new concept of monotonicity for nonlinear differential operators-nonlinear monotonicity concept-and on its basis we obtain new phenomena for solutions, subsolutions and supersolutions of the well-known quasilinear differential equations. In the second part we omit the current coerciveness condition and change it by a weaker one. In spite of this we obtain a series of new qualitative properties of solutions for wide classes of quasilinear parabolic inequalities. Most of these properties are also new for solutions of the well-known equations, which we consider in the paper. 相似文献
12.
The basic geometric and physical relations and resolving equations of the theory of thin and nonthin orthotropic composite shells with account of nonlinear properties and low shear rigidity of their materials are presented. They are derived based on two theories, namely the theory of anisotropic shells employing the Timoshenko or Kirchhoff-Love hypothesis and the nonlinear theory of elasticity and plasticity of anisotropic media in combination with the Lagrange variational principle. The procedure and algorithm for the numerical solution of nonlinear (linear) problems are based on the method of successive approximations, the difference-variational method, and the Lagrange multiplier method. Calculations of the stress-strain state for a spherical shell with a circular opening loaded with internal pressure are presented. The effect of transverse shear strains and physical nonlinearity of the material on the distribution of maximum deflections and circumferential stresses in the shell, obtained according to two variants of the shell theories, is studied. A comparison of the results of the problem solution in linear and nonlinear statements with and without account of the shell shear strains is given. The numerical data obtained for thin and nonthin (medium thick) composite shells are analyzed. 相似文献
13.
The paper studies the first homology of finite regular branched coverings of a universal Borromean orbifold called B
4,4,4ℍ3. We investigate the irreducible components of the first homology as a representation space of the finite covering transformation
group G. This gives information on the first betti number of finite coverings of general 3-manifolds by the universality of B
4,4,4. The main result of the paper is a criterion in terms of the irreducible character whether a given irreducible representation
of G is an irreducible component of the first homology when G admits certain symmetries. As a special case of the motivating argument the criterion is applied to principal congruence
subgroups of B
4,4,4. The group theoretic computation shows that most of the, possibly nonprincipal, congruence subgroups are of positive first
Betti number.
This work is partially supported by the Sonderforschungsbereich 288. 相似文献
14.
ChenDan YangXiaoling 《分析论及其应用》2004,20(2):167-174
thenandIn this paper, a lemma as a new method to calculate the Hausdorff measure of fractal is given. And the exact values of Hausdorff measure of a class of Sierpinski sets which satisfy balance distribution ang dimension ≤1 are obtained 相似文献
15.
It is considered the class of Riemann surfaces with dimT1 = 0, where T1 is a subclass of exact harmonic forms which is one of the factors in the orthogonal decomposition of the spaceΩH of harmonic forms of the surface, namely The surfaces in the class OHD and the class of planar surfaces satisfy dimT1 = 0. A.Pfluger posed the question whether there might exist other surfaces outside those two classes. Here it is shown that in the case of finite genus g, we should look for a surface S with dimT1 = 0 among the surfaces of the form Sg\K , where Sg is a closed surface of genus g and K a compact set of positive harmonic measure with perfect components and very irregular boundary. 相似文献
16.
W.M.Shah A.Liman 《分析论及其应用》2004,20(1):16-27
Let P(z)=∑↓j=0↑n ajx^j be a polynomial of degree n. In this paper we prove a more general result which interalia improves upon the bounds of a class of polynomials. We also prove a result which includes some extensions and generalizations of Enestrǒm-Kakeya theorem. 相似文献
17.
Brandon Chabaud M. Carme Calderer 《Mathematical Methods in the Applied Sciences》2016,39(6):1395-1409
We propose and analyze a mathematical model of the mechanics of gels, consisting of the laws of balance of mass and linear momentum of the polymer and liquid components of the gel. We consider a gel to be an immiscible and incompressible mixture of a nonlinearly elastic polymer and a fluid. The problems that we study are motivated by predictions of the life cycle of body‐implantable medical devices. Scaling arguments suggest neglecting inertia terms, and therefore, we consider the quasi‐static approximation to the dynamics. We focus on the linearized system about stress‐free states, uniform expansions, and compressions and derive sufficient conditions for the solvability of the time‐dependent problems. These turn out to be conditions that guarantee local stability of the equilibrium solutions. We also consider non‐stress free equilibria and states with residual stress and derive an energy law for the corresponding time‐dependent system. The conditions that guarantee stability of solutions provide a selection criteria of the material parameters of devices. The boundary conditions that we consider are of two types, displacement‐traction and permeability of the gel surface to the fluid. We address the cases of viscous and inviscid solvent, assume Newtonian dissipation for the polymer component, and establish existence of weak solutions for the different boundary permeability conditions and viscosity assumptions. We present two‐dimensional, finite element numerical simulations to study stress concentration on edges, this being the precursor to debonding of the gel from its substrate. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
18.
A.Al-Shuaibi F.Al-Rawjih 《分析论及其应用》2004,20(1):28-34
Given the Laplace transform F(s) of a function f(t), we develop a new algorithm to find an approximation to f(t) by the use of the classical Jacobi polynomials. The main contribution of our work is the development of a new and very effective method to determine the coefficients in the finite series expansion that approximation f(t) in terms of Jacobi polynomials. Some numerical examples are illustrated. 相似文献
19.
T. M. Ulyanova N. P. Krut'ko L. V. Titova S. V. Medichenko 《Mechanics of Composite Materials》2005,41(6):561-566
The crystalline and porous structure of superfine powders and fibers made of alumina and zirconia doped with yttria is investigated.
The particle sizes were determined by the methods of coherent dispersion and scanning transmission electron microscopy. Based
on data on the sizes of crystallites of the metal oxides, which were obtained by different methods, it is found that crystalline
transformations of the oxides lead to dispersion of the materials. The structural transformations of the superfine oxides
are accompanied by changes in crystallite sizes and in the character and size of pores. The laws established allow one to
purposefully control the process of producing nanostructured oxide powders and fibers, which can be utilized as active fillers
for composite materials based on various matrices.
__________
Translated from Mekhanika Kompozitnykh Materialov, Vol. 41, No. 6, pp. 831–840, November–December, 2005. 相似文献
20.
We argue that the epistemic theory of vagueness cannot adequately justify its key tenet-that vague predicates have precisely
bounded extensions, of which we are necessarily ignorant. Nor can the theory adequately account for our ignorance of the truth
values of borderline cases. Furthermore, we argue that Williamson’s promising attempt to explicate our understanding of vague
language on the model of a certain sort of “inexact knowledge” is at best incomplete, since certain forms of vagueness do
not fit Williamson’s model, and in fact fit an alternative model. Finally, we point out that a certain kind of irremediable
inexactitude postulated by physics need not be-and is not commonly-interpreted as epistemic. Thus, there are aspects of contemporary
science that do not accord well with the epistemicist outlook. 相似文献