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101.
刘秀贵 《数学物理学报(A辑)》2007,27(2)
决定球面稳定同伦群是同伦论中的核心问题之一,是非常重要的.该文证明:球面稳定同伦元素α1β1βs是一个阶为p的非平凡元素,其中p≥5是任意奇素数,1≤s
相似文献
102.
ON THE EXISTENCE OF ZERO POINTS OF A CONTINUOUS FUNCTION 总被引:3,自引:1,他引:2
J.M. SorianoDepartamento de Andlisis Matematico Facultad de Matemdticas Universidad de Sevilla Aptdo. Sevilla Spain 《数学物理学报(B辑英文版)》2002,22(2)
IPreliminarlesTheee。etOOk totot比OO。stsllCCdCSdO‘lOll‘。山OOqll时1OO/(。)=。,SS山 SFSSdPoint Theorems[‘’,”],Degree Theory【9,15].In general these are used when f aPPlies a set ora space on itself.Cm眈inn眈ion Methods can be used to test the existence ofa solution whenf pplies a set or a sp。e on it咖‘-’,”-“l,or aPPlies a set or sP。m another sP。,s。M see here.wrthermore,contlnuulon methods pve us the exlstence ofcurves wb讪 can beused to CalCttlue the Sdutionsl6… 相似文献
103.
It has been proved that if a rectangle is dissected into three congruent pieces,then those pieces must themselves be rectangles. In the present paper this result is generalized to the case of parallelogram. 相似文献
104.
R. W. Kieboom 《Applied Categorical Structures》1997,5(2):131-142
It is well known that the concept of monomorphism in a category can be defined using an appropriate pullback diagram. In the homotopy category of TOP pullbacks do not generally exist. This motivated Michael Mather to introduce another notion of homotopy pullback which does exist. The aim of this paper is to investigate the modified notion of homotopy monomorphism obtained by applying the pullback characterization using Mather's homotopy pullback. The main result of Section 1 shows that these modified homotopy monomorphisms are exactly those homotopy monomorphisms (in the usual sense) which are homotopy pullback stable, hence the terminology “stable” homotopy monomorphism. We also link these stable homotopy monomorphisms to monomorphisms and products in the track homotopy category over a fixed space. In Section 2 we answer the question: when is a (weak) fibration also a stable homotopy monomorphism? In the final section it is shown that the class of (weak) fibrations with this additional property coincides with the class of “double” (weak) fibrations. The double (weak) covering homotopy property being introduced here is a stronger version of the (W) CHP in which the final maps of the homotopies involved play the same role as the initial maps. 相似文献
105.
It is proved that algebraic and topological K-functors are isomorphic on the category of stable generalized operator algebras which are K
i
-regular for all i > 0. 相似文献
106.
组合同伦方法在无界域上的收敛性 总被引:3,自引:0,他引:3
组合同伦内点法由Feng等提出,是求解有界区域上的非凸数学规划的一种大范围收敛性方法,本文证明此算法适用于某些无界区域上的非凸数学规划问题。 相似文献
107.
A New Decomposition Technique in Solving Multistage Stochastic Linear Programs by Infeasible Interior Point Methods 总被引:1,自引:0,他引:1
Multistage stochastic linear programming (MSLP) is a powerful tool for making decisions under uncertainty. A deterministic equivalent problem of MSLP is a large-scale linear program with nonanticipativity constraints. Recently developed infeasible interior point methods are used to solve the resulting linear program. Technical problems arising from this approach include rank reduction and computation of search directions. The sparsity of the nonanticipativity constraints and the special structure of the problem are exploited by the interior point method. Preliminary numerical results are reported. The study shows that, by combining the infeasible interior point methods and specific decomposition techniques, it is possible to greatly improve the computability of multistage stochastic linear programs. 相似文献
108.
Giovanna Idone 《Journal of Global Optimization》2004,28(1):45-53
A continuum model of transportation network is considered in presence of capacity constraints on the flow. The equilibrium conditions are expressed in terms of a Variational Inequality for which an existence theorem is provided. 相似文献
109.
Wiesława T. Obuchowska 《Computational Optimization and Applications》2004,29(1):69-90
In this paper we analyze properties of the analytic centers for perturbed convex problems. In particular we study the continuity of convex regions with respect to such characteristics as boundedness, full dimensionality and the existence of an analytic centre. Furthermore, we state the necessary and sufficient conditions for the existence of the analytic centre for possibly unbounded regions and we show that the analytic centre is identical for any minimal representation of the convex set. We are also concerned with the limiting behaviour of the central path as it approaches the set of optimal solutions of the problem. 相似文献
110.
Thomas Lorenz 《Set-Valued Analysis》2006,14(3):209-247
The well-known Reynold's Transport Theorem deals with the integral over a time-dependent set (that is evolving along a smooth vector field) and specifies its semiderivative with respect to time. Here reachable sets of differential inclusions are considered instead. Dispensing with any assumptions about the regularity of the compact initial set, we give sufficient conditions on the differential inclusion for the absolute continuity (of the integral) with respect to time and its weak derivative is formulated as a Hausdorff integral over the topological boundary. 相似文献