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91.
Let be a nonempty closed convex subset of a real Banach space and be a Lipschitz pseudocontractive self-map of with . An iterative sequence is constructed for which as . If, in addition, is assumed to be bounded, this conclusion still holds without the requirement that Moreover, if, in addition, has a uniformly Gâteaux differentiable norm and is such that every closed bounded convex subset of has the fixed point property for nonexpansive self-mappings, then the sequence converges strongly to a fixed point of . Our iteration method is of independent interest.
92.
For any subset A of the unit sphere of a Banach space X and for [0,2) the notion of -flatness is introduced as a measure of non-flatness of A. For any positive , construction of locally finite tilings of the unit sphere by -flat sets is carried out under suitable -renormings of X in a quite general context; moreover, a characterization of spaces having separable dual is provided in terms of the existence of such tilings. Finally, relationships between the possibility of getting such tilings of the unit sphere in the given norm and smoothness properties of the norm are discussed. 相似文献
93.
Christopher Allday Bernhard Hanke Volker Puppe 《Proceedings of the American Mathematical Society》2003,131(10):3275-3283
Let , or more generally be a finite -group, where is an odd prime. If acts on a space whose cohomology ring fulfills Poincaré duality (with appropriate coefficients ), we prove a mod congruence between the total Betti number of and a number which depends only on the -module structure of . This improves the well known mod congruences that hold for actions on general spaces.
94.
Regina Sandra Burachik B. F. Svaiter 《Proceedings of the American Mathematical Society》2003,131(8):2379-2383
Recently, the authors studied the connection between each maximal monotone operator and a family of convex functions. Each member of this family characterizes the operator and satisfies two particular inequalities.
The aim of this paper is to establish the converse of the latter fact. Namely, that every convex function satisfying those two particular inequalities is associated to a unique maximal monotone operator.
95.
S. J. Brodsky 《The European Physical Journal A - Hadrons and Nuclei》2007,31(4):638-644
The AdS/CFT correspondence between conformal field theory and string states in an extended space-time has provided new insights
into not only hadron spectra, but also their light-front wave functions. We show that there is an exact correspondence between
the fifth-dimensional coordinate of anti-de Sitter space z and a specific impact variable ζ which measures the separation of the constituents within the hadron in ordinary space-time. This connection allows one to
predict the form of the light-front wave functions of mesons and baryons, the fundamental entities which encode hadron properties
and scattering amplitudes. A new relativistic Schr?dinger light-front equation is found which reproduces the results obtained
using the fifth-dimensional theory. Since they are complete and orthonormal, the AdS/CFT model wave functions can be used
as an initial ansatz for a variational treatment or as a basis for the diagonalization of the light-front QCD Hamiltonian.
A number of applications of light-front wave functions are also discussed. 相似文献
96.
We analyze the finite temperature behavior of the Sakai-Sugimoto model, which is a holographic dual of a theory which spontaneously breaks a U(Nf)L × U(Nf)R chiral flavor symmetry at zero temperature. The theory involved is a 4 + 1 dimensional supersymmetric SU(Nc) gauge theory compactified on a circle of radius R with anti-periodic boundary conditions for fermions, coupled to Nf left-handed quarks and Nf right-handed quarks which are localized at different points on the compact circle (separated by a distance L). In the supergravity limit which we analyze (corresponding in particular to the large Nc limit of the gauge theory), the theory undergoes a deconfinement phase transition at a temperature Td = 1/2πR. For quark separations obeying L > Lc ? 0.97 ∗ R the chiral symmetry is restored at this temperature, but for L < Lc ? 0.97 ∗ R there is an intermediate phase which is deconfined with broken chiral symmetry, and the chiral symmetry is restored at TχSB ? 0.154/L. All of these phase transitions are of first order. 相似文献
97.
Hsien-Chung Wu 《Fuzzy Optimization and Decision Making》2003,2(1):61-73
The concept of fuzzy scalar (inner) product that will be used in the fuzzy objective and inequality constraints of the fuzzy primal and dual linear programming problems with fuzzy coefficients is proposed in this paper. We also introduce a solution concept that is essentially similar to the notion of Pareto optimal solution in the multiobjective programming problems by imposing a partial ordering on the set of all fuzzy numbers. We then prove the weak and strong duality theorems for fuzzy linear programming problems with fuzzy coefficients. 相似文献
98.
Fusion Operators and Cocycloids in Monoidal Categories 总被引:1,自引:0,他引:1
Ross Street 《Applied Categorical Structures》1998,6(2):177-191
The Yang–Baxter equation has been studied extensively in the context of monoidal categories. The fusion equation, which appears to be the Yang–Baxter equation with a term missing, has been studied mainly in the context of Hilbert spaces. This paper endeavours to place the fusion equation in an appropriate categorical setting. Tricocycloids are defined; they are new mathematical structures closely related to Hopf algebras. 相似文献
99.
曾韧英 《应用数学与计算数学学报》1997,11(1):27-32
本文讨论定义在Banach空间上的,既具有等式约束又具有不等式约束的,非光滑(F,P)不变凸多目标规划的Wolfe对偶性,Mond-Weir型对偶性可类似讨论之。 相似文献
100.
Necessary and sufficient conditions in constrained optimization 总被引:22,自引:0,他引:22
Additional conditions are attached to the Kuhn-Tucker conditions giving a set of conditions which are both necessary and sufficient
for optimality in constrained optimization, under appropriate constraint qualifications. Necessary and sufficient conditions
are also given for optimality of the dual problem. Duality and converse duality are treated accordingly. 相似文献