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111.
A spread of
is a set of l-dimensional subspaces L V partitioning V {0}. We construct examples of compact spreads that are identical with their sets of orthogonal spaces L
. In the corresponding topological translation planes, every Euclidean sphere is a unital with the additional property that every point at infinity has flat feet. 相似文献
112.
Let (X, F) be an Alexandroff space, let A(F) be the Boolean subalgebra of 2
X
generated by F, let G be a Hausdorff commutative topological lattice group and let rbaF(A(F), G) denote the set of all order bounded F-inner regular finitely additive set functions from A(F) into G. Using some special properties of the elements of rbaF(A(F), G), we extend to this setting the first decomposition theorem of Alexandroff. 相似文献
113.
Stavros Tsalidis 《K-Theory》2000,21(2):151-199
We investigate étale descent properties of topological Hochschild and cyclic homology. Using these properties we deduce a general injectivity result for the descent map in algebraic K-theory, and show that algebraic K-theory has étale descent for rings of integers in unramified and tamely ramified p-adic fields. 相似文献
114.
Large volume growth and finite topological type 总被引:5,自引:0,他引:5
D. Ordway B. Stephens D. G. Yang 《Proceedings of the American Mathematical Society》2000,128(4):1191-1196
It is shown in this paper that a complete noncompact -dimensional Riemannian manifold with nonnegative Ricci curvature, sectional curvature bounded from below, and large volume growth is of finite topological type provided that the volume growth rate of the complement of the cone of rays from a fixed base point is less than .
115.
The static and evolutionary properties of two-dimensional cellular structures, or froths, are discussed in the light of recent work on structuring of the froth into concentric shells. Of interest is the dual role of a topological dislocation (defect) in an otherwise uniform froth, considered both as a source of disorder and also as a source generating a shell-structured froth. We present simulations on an initially uniform hexagonal froth. A defect is introduced by forcing either a T1 or T2 process in the stable structure, after which the froth is allowed to evolve according to von Neumann's law. In the first case, topological inclusions are found in the first few layers early in the evolution. In the second case, no inclusions appear over the entire evolutionary period. The growing disorder (as measured by the second moment of the side distribution,
2) is isotropic. For the special case of a T2-formed froth in a uniform network, the SSI structure is retained with
20 only for the zeroth, first, and second layers. The ratio between topological perimeter and radius of the shells is close to 6, the value for a hexagonal froth. 相似文献
116.
Zhu ZhengHe 《中国科学G辑(英文版)》2007,50(5):581-590
This work presents a new science called atomic and molecular reaction statics (AMRS). There are four parts for AMRS, i.e.
the group theoretical derivation of molecular electronic states, the principle of microscopic reversibility, the principle
of microscopic transitivity and the optimum energy process rule. AMRS has been developed for about twenty years. 相似文献
117.
葛洵 《纯粹数学与应用数学》2010,26(3)
证明了如果空间类κ为D-空间类或闭遗传不可约空间类,则I(κ)(∈)κ.这一结果对于κ为D空间类和闭遗传不可约空间类,肯定地回答了I(κ)是否包含I2(κ)问题. 相似文献
118.
Static reanalysis for topological modifications of structures 总被引:1,自引:0,他引:1
A procedure for reanalysis of various structures subjected to various topological modifications is presented. The procedure
is based on the results of a single exact analysis and the factorization of the stiffness matrix of initial structures. It
is suitable for the case of addition of joints, where the number of the degrees of freedom is increased. The method deals
with the stiffness matrix of structures directly, so it can be used with a general finite element system. It is shown that
the proposed approximation method is most effective in terms of accuracy, efficiency, and ease of implementation. 相似文献
119.
By using φ-mapping topological current theory and gauge potential decomposition, we discuss the self-dual equation and its solution in the SU(N) Dunne-Jackiw-Pi-Trugenberger model and obtain a new concrete self-dual equation with a δ function. For the SU(3) case, we obtain a new self-duality solution and find the relationship between the soliton solution and topological number which is determined by the Hopf index and Brouwer degree of φ-mapping. In our solution, the flux of this soliton is naturally quantized. 相似文献
120.
Sneha Karmarkar P. V. Khadikar Vijay K. Agrawal Keshav C. Mathur Manorama Mandloi Shobha Joshi 《Journal of Chemical Sciences》2000,112(1):43-49
Proton-ligand formation constants of salicylhydroxamic acids (SHA) and their nuclear substituted derivatives have been estimated
topologically using the normalized Wiener index, referred to as mean square Wiener index (Wms). Regression analysis of the
data indicates that Wms can be used successfully for estimating and monitoring proton-ligand formation constants. 相似文献