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911.
Harald Brandenburg 《Topology and its Applications》1985,20(1):17-27
Following Pareek a topological space X is called D-paracompact if for every open cover of X there exists a continuous mapping f from X onto a developable T1-space Y and an open cover of Y such that { f-1[B]|B ∈ } refines . It is shown that a space is D-paracompact if and only if it is subparacompact and D-expandable. Moreover, it is proved that D-paracompactness coincides with a covering property, called dissectability, which was introduced by the author in order to obtain a base characterization of developable spaces. 相似文献
912.
We show that the following classes of topological spaces coincide: (1) stratifiable μ-spaces, (2) stratifiable spaces with an M-structure, (3) regularly stratifiable spaces, and (4) strongly regularly stratifiable spaces. 相似文献
913.
In this paper we prove that p-spaces and ?ech-complete spaces with Gδ-diagonals can be characterized by a familiar function extension property. 相似文献
914.
Munehiko Itō 《Topology and its Applications》1985,19(1):65-69
Let X be an M3-space. If every point of X has a closure preserving outer base, then X is an M1-space. This is a remarkable improvement on [2, Corollary 2.8]. If there is a point of X having no closure preserving outer base, then we have an M3-space which is not M1. 相似文献
915.
James C. Fu 《Statistics & probability letters》1985,3(2):101-105
In this paper the exponential rates, bounds, and local exponential rates for likelihood ratio estimators are studied. Under certain regularity conditions, a family of likelihood ratio estimators is shown to be admissible in exponential rate. It is also shown that the maximum likelihood estimator is the limit of this family of estimators. 相似文献
916.
It is proved that the correlation coefficient between the elements of the order statistics is maximal for a rectangularly (uniformly) distributed population. 相似文献
917.
We discuss both pathwise and mean-square convergence of several approximation schemes to stochastic differential equations. We then estimate the corresponding speeds of convergence, the error being either the mean square error or the error induced by the approximation on the value of the expectation of a functional of the solution. We finally give and comment on a few comparative simulation results. 相似文献
918.
J. -L. Charvet R. Dayras D. Durand O. Lopez D. Cussol D. Dor L. Nalpas A. Van Lauwe C. Volant 《Nuclear Physics A》2004,730(3-4):431-447
A previous analysis of the charge (Z) correlations in the ΔZ−Z plane for 129Xe+natSn central collisions at 32 MeV/n has shown an enhancement in the production of equally sized fragments (low ΔZ) which was interpreted as an evidence for spinodal decomposition. However, the signal is weak and rises the question of the estimation of the uncorrelated yield. After a critical analysis of its robustness, we propose in this paper a new technique to build the uncorrelated yield in the charge correlation function. The application of this method to 129Xe+natSn central collision data at 32, 39, 45 and 50 MeV/n does not show any particular enhancement of the correlation function in any ΔZ bin. 相似文献
919.
We present the first quadratic-time algorithm for the greedy triangulation of a finite planar point set, and the first linear-time algorithm for the greedy triangulation of a convex polygon. 相似文献
920.
D. Juriev 《Letters in Mathematical Physics》1991,22(1):11-14
A version, based on infinite-dimensional geometry, of the generally covariant closed string-field theory is proposed. 相似文献