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31.
We establish upper and lower bounds for the metric entropy and bracketing entropy of the class of d-dimensional bounded monotonic functions under Lp norms. It is interesting to see that both the metric entropy and bracketing entropy have different behaviors for p<d/(d-1) and p>d/(d-1). We apply the new bounds for bracketing entropy to establish a global rate of convergence of the MLE of a d-dimensional monotone density. 相似文献
32.
We continue the studies on the so–called genuine Bernstein–Durrmeyer operators U
n
by establishing a recurrence formula for the moments and by investigating the semigroup T(t) approximated by U
n
. Moreover, for sufficiently smooth functions the degree of this convergence is estimated. We also determine the eigenstructure
of U
n
, compute the moments of T(t) and establish asymptotic formulas.
Received: January 26, 2007. 相似文献
33.
Masahiro Kubo 《Journal of Evolution Equations》2007,7(4):701-717
We study an abstract second order nonlinear evolution equation in a real Hilbert space. We consider time-dependent convex
functions and their subdifferentials operating on the first derivative of the unknown function. Introducing appropriate assumptions
on the convex functions and other data, we prove the existence and uniqueness of a strong solution, and give some applications
of the abstract theorem to hyperbolic variational inequalities with time-dependent constraints.
相似文献
34.
We define the Sheffer group of all Sheffer-type polynomials and prove the isomorphism between the Sheffer group and the Riordan group. An equivalence of the Riordan array pair and generalized Stirling number pair is also presented. Finally, we discuss a higher dimensional extension of Riordan array pairs. 相似文献
35.
Jan J. Dijkstra 《Topology and its Applications》2006,153(15):2948-2951
In 1988 A. Gutek proved that there exist one-point connectifications of hereditarily disconnected spaces that do not have the fixed point property. We improve on this result by constructing a one-point connectification of a totally disconnected space without the fixed point property. 相似文献
36.
Debora Di Caprio 《Topology and its Applications》2006,153(14):2680-2702
We introduce and study some completeness properties for systems of open coverings of a given topological space. A Hausdorff space admitting a system of cardinality κ satisfying one of these properties is of type Gκ. Hence, we define several new variants of the ?ech number and use elementary submodels to determine further results. We introduce M-hulls and M-networks, for M elementary submodel. As an application, we give estimates for both the tightness and the Lindelöf number of a generic upper hyperspace. Two recent results of Costantini, Holá and Vitolo on the tightness of co-compact hyperspaces follow from ours as corollaries. 相似文献
37.
Andrea Loi 《Differential Geometry and its Applications》2006,24(3):311-319
In this paper we study the Calabi diastasis function of Hermitian symmetric spaces. This allows us to prove that if a complete Hermitian locally symmetric space (M,g) admits a Kähler immersion into a globally symmetric space (S,G) then it is globally symmetric and the immersion is injective. Moreover, if (S,G) is symmetric of a specified type (Euclidean, noncompact, compact), then (M,g) is of the same type. We also give a characterization of Hermitian globally symmetric spaces in terms of their diastasis function. Finally, we apply our analysis to study the balanced metrics, introduced by Donaldson, in the case of locally Hermitian symmetric spaces. 相似文献
38.
Common fixed-point results are established for a new class of noncommuting selfmaps. We apply them to obtain several invariant approximation results which unify, extend, and complement well-known results. 相似文献
39.
Given an integer n ≥ 2, let λ(n) := (log n)/(log γ(n)), where γ(n) = Π
p|n p, stand for the index of composition of n, with λ(1) = 1. We study the distribution function of (λ(n) – 1) log n as n runs through particular sets of integers, such as the shifted primes, the values of a given irreducible cubic polynomial
and the shifted powerful numbers.
Research supported in part by a grant from NSERC.
Research supported by the Applied Number Theory Research Group of the Hungarian Academy of Science and by a grant from OTKA.
Professor M.V. Subbarao passed away on February 15, 2006.
Received: 3 March 2006 Revised: 28 October 2006 相似文献
40.
This paper examines the steady state behaviour of a batch arrival queue with two phases of heterogeneous service along and Bernoulli schedule vacation under multiple vacation policy, where after two successive phases service or first vacation the server may go for further vacations until it finds a new batch of customer in the system. We carry out an extensive stationary analysis of the system, including existence of stationary regime, queue size distribution of idle period process, embedded Markov chain steady state distribution of stationary queue size, busy period distribution along with some system characteristics. 相似文献