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291.
A general theory for the approximate solution of nonlinear operator equations where the solution lies in some real or complex Hilbert space is developed. It is shown that the techniques can be applied to a variety of problems taken from the theories of plasma physics, colloid theory, and the theory of current flow in nerve membranes. 相似文献
292.
L.J. Ratliff 《Journal of Pure and Applied Algebra》1978,12(2):159-175
A chain condition intermediate to the catenary property and the chain condition for prime ideals (c.c.) is studied. Like the c.c., the condition is inherited from a semi-local domain R by integral extension domains, by local quotient domains, and by factor domains, and a semi-local ring that satisfies the condition is catenary. (Unlike the c.c., none of these statements is true when R is not semi-local.) A number of characterizations of a semi-local domain that satisfies the condition are given in terms of: integral (respectively, algebraic, transcendental) extension domains, Henselizations, completions, Rees rings, associated graded rings and certain discrete valuation over-rings. Then four of the catenary chain conjectures are characterized in terms of this condition. 相似文献
293.
N. Ottavy 《Journal of Optimization Theory and Applications》1988,56(3):433-461
Many mathematical and applied problems can be reduced to finding a common point of a system of convex sets. The aim of this paper is twofold: first, to present a unified framework for the study of all the projection-like methods, both parallel and serial (chaotic, mostremote set, cyclic order, barycentric, extrapolated, etc.); second, to establish strong convergence results for quite general sets of constraints (generalized Slater, generalized uniformly convex, made of affine varieties, complementary, etc.). This is done by introducing the concept of regular family. We proceed as follows: first, we present definitions, assumptions, theorems, and conclusions; thereafter, we prove them. 相似文献
294.
P. Masani 《Journal of multivariate analysis》1977,7(2):292-335
We extend the Lévy inversion formula for the recovery of a bounded measure over from its Fourier-Stieltjes transform to bounded complex-valued, orthogonally scattered Hilbert space-valued, and spectral projection operator-valued measures over any first countable locally compact Abelian group. All our results are direct generalizations of known inversions for . 相似文献
295.
T.A. Chapman 《Topology and its Applications》1982,14(3):247-262
In this paper a boundary theorem for Hilbert cube manifolds is established,where it is required that the boundary be put on the manifold with arbitrarily small control in a given compact metric parameter space. 相似文献
296.
The authors investigate the Toeplitz C^≠-algebra over the L-shaped domain in C^n by the groupoid approach, and successfully parameterize the unit space of the groupoid assocated to the Toeplitz C^≠-algebra. 相似文献
297.
关于hilbert-ingham不等式和它的应用 总被引:5,自引:1,他引:4
本文给出(i)hilbert不等式和hilbert-ingham不等式一些有意义的共同改进;(ii)一些fejer-riesz型不等式的改进和(iii)hardy不等式的改进. 相似文献
298.
A note on closed images of locally compact metric spaces 总被引:1,自引:0,他引:1
Shou Lin 《Acta Mathematica Hungarica》2005,109(1-2):157-162
Summary A decomposition theorem about closed images of locally compact metric spaces is discussed. It is shown that a space is a closed
image of a locally compact metric space if and only if it is a regular Fréchet space with a point-countable k-network, and each of its closed first-countable subset is locally compact. 相似文献
299.
The functional dimension of countable Hilbert spaces has been discussed by some authors. They showed that every countable Hilbert space with finite functional dimension is nuclear. In this paper the authors do further research on the functional dimension, and obtain the following results: (1) They construct a countable Hilbert space, which is nuclear, but its functional dimension is infinite. (2) The functional dimension of a Banach space is finite if and only if this space is finite dimensional. (3) Let B be a Banach space, B* be its dual, and denote the weak * topology of B* by σ(B*,B). Then the functional dimension of (B*,σ(B*,B)) is 1. By the third result, a class of topological linear spaces with finite functional dimension is presented. 相似文献
300.
D. V. Gorbachev 《Mathematical Notes》1997,61(4):430-439
For a functional on the classH
ω
(n)
,n≥3, we construct the extremal function on which the upper bound obtained by A. I. Stepanets is attained.
Translated fromMatematicheskie Zametki, Vol. 61, No. 4, pp. 519–529, April, 1997.
Translated by N. K. Kulman 相似文献