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981.
Bengt Lindberg 《BIT Numerical Mathematics》1989,29(2):369-371
982.
Summary. It is well-known that Brownian motion has no points of increase. We show that an analogous statement for the Brownian sheet
is false. More precisely, for the standard Brownian sheet in the positive quadrant, we prove that there exist monotone curves
along which the sheet has a point of increase.
Received: 7 December 1994 / In revised form: 6 August 1996 相似文献
983.
The issue is that of following the path of a Brownian particle by a process of bounded total variation and subject to a reflecting barrier at the origin, in such a way as to minimize expected total cost over a finite horizon. We establish the existence of optimal processes and the dynamic programming equations for this question, and show (by purely probabilistic arguments) its relation to an appropriatefamily of optimal stopping problems with absorption at the origin.Work carried out during a visit by the second author at the University Pierre et Marie Curie (Paris VI), and at INRIA (Institut National de Recherche en Informatique et en Automatique). The hospitality of these institutions is gratefully acknowledged.Research supported in part by the U.S. Air Force Office of Scientific Research, under grant AFOSR-86-0203. 相似文献
984.
Ernst S. Selmer 《BIT Numerical Mathematics》1989,29(1):37-40
A boundO(N
1+1/k
) for the running time of Shellsort, withO(logN) passes, is proved very simply by application of a Frobenius basis withk elements. 相似文献
985.
Lois Mansfield 《Numerische Mathematik》1984,45(2):165-172
Summary Optimal rates of convergence for the approximate solution of the stationary Stokes equations are obtained for finite element schemes which use piecewise constants to approximate the pressure and piecewise linear or piecewise bilinear or trilinear polynomials to approximate the velocity over fairly general quadrilateral or hexahedral meshes.This research was supported by NSF Grant MC80-16532 相似文献
986.
We construct connected, locally connected, almost regular, countable, Urysohn spaces. This answers a problem of G.X. Ritter. We show that there are 2c such non-homeomorphic spaces. We also show that there are 2c non-homeomorphic spaces which are further rigid. We discuss the group of homeomorphisms of such spaces.The following question was raised by G.X. Ritter: Does there exist a countable connected locally connected Urysohn space which is almost regular? We answer this question in the affirmative and in fact, show that not only are there as many as 2c such spaces but that there are just as many rigid spaces with the same properties. Furthermore we show that every countable Urysohn space is a subspace of such a space. We also prove that every countable group is isomorphic to the group of autohomeomorphisms of some connected locally connected almost regular Urysohn space. Examples are given of groups of order c which can be represented in this manner. 相似文献
987.
Pranab Kumar Sen 《Statistics & probability letters》1984,2(4):193-196
For testing the hypothesis that two (symmetric) distributions may differ only in locations, a Kolmogorov-Smirnov type test based on the aligned observations is considered and its properties are studied. 相似文献
988.
For the Gaussian channel Y(t) = Φ(ξ(s), Y(s); s ≦ t) + X(t), the mutual information I(ξ, Y) between the message ξ(·) and the output Y(·) is evaluated, where X(·) is a Gaussian noise. Furthermore, the optimal coding under average power constraints is constructed. 相似文献
989.
A.Larry Wright 《Journal of multivariate analysis》1982,12(2):178-185
Two related almost sure limit theorems are obtained in connection with a stochastic process {ξ(t), ?∞ < t < ∞} with independent increments. The first result deals with the existence of a simultaneous stabilizing function H(t) such that for almost all sample functions of the process. The second result deals with a wide-sense stationary process whose random spectral distributions is ξ. It addresses the question: Under what conditions does converge as T → ∞ for all τ for almost all sample functions? 相似文献
990.