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1.
We determine the L p discrepancy of the two-dimensional Hammersley point set in base b. These formulas show that the L p discrepancy of the Hammersley point set is not of best possible order with respect to the general (best possible) lower bound on L p discrepancies due to Roth and Schmidt. To overcome this disadvantage we introduce permutations in the construction of the Hammersley point set and show that there always exist permutations such that the L p discrepancy of the generalized Hammersley point set is of best possible order. For the L 2 discrepancy such permutations are given explicitly. F.P. is supported by the Austrian Science Foundation (FWF), Project S9609, that is part of the Austrian National Research Network “Analytic Combinatorics and Probabilistic Number Theory”.  相似文献   

2.
We derive a lower bound of L p norms, 1 ⩽ p ⩽ ∞, in the central limit theorem for strongly mixing random variables X 1,..., X n with under the boundedness condition ℙ{|X i | ⩽ M} = 1 with a nonrandom constantM > 0 and condition ∑ r⩾1 r 2α(r) < ∞, where α(r) are the Rosenblatt strong mixing coefficients. __________ Translated from Lietuvos Matematikos Rinkinys, Vol. 45, No. 4, pp. 587–602, October–December, 2005.  相似文献   

3.
L p approximation capability of radial basis function (RBF) neural networks is investigated. If g: R +1R 1 and ∈ L loc p (R n ) with 1 ≤ p < ∞, then the RBF neural networks with g as the activation function can approximate any given function in L p (K) with any accuracy for any compact set K in R n , if and only if g(x) is not an even polynomial. Partly supported by the National Natural Science Foundation of China (10471017)  相似文献   

4.
Given 1≤ p,q < ∞, let BLpLq be the class of all Banach lattices X such that X is isometrically lattice isomorphic to a band in some Lp(Lq)-Banach lattice. We show that the range of a positive contractive projection on any BLpLq-Banach lattice is itself in BLpLq. It is a consequence of this theorem and previous results that BLpLq is first-order axiomatizable in the language of Banach lattices. By studying the pavings of arbitrary BLpLq-Banach lattices by finite dimensional sublattices that are themselves in this class, we give an explicit set of axioms for BLpLq. We also consider the class of all sublattices of Lp(Lq)-Banach lattices; for this class (when p/q is not an integer) we give a set of axioms that are similar to Krivine’s well-known axioms for the subspaces of Lp-Banach spaces (when p/2 is not an integer). We also extend this result to the limiting case q = ∞.  相似文献   

5.
We consider the solutions of refinement equations written in the form
where the vector of functions ϕ = (ϕ 1, ..., ϕ r ) T is unknown, g is a given vector of compactly supported functions on ℝ s , a is a finitely supported sequence of r × r matrices called the refinement mask, and M is an s × s dilation matrix with m = |detM|. Inhomogeneous refinement equations appear in the construction of multiwavelets and the constructions of wavelets on a finite interval. The cascade algorithm with mask a, g, and dilation M generates a sequence ϕ n , n = 1, 2, ..., by the iterative process
from a starting vector of function ϕ 0. We characterize the L p -convergence (0 < p < 1) of the cascade algorithm in terms of the p-norm joint spectral radius of a collection of linear operators associated with the refinement mask. We also obtain a smoothness property of the solutions of the refinement equations associated with the homogeneous refinement equation. This project is supported by the NSF of China under Grant No. 10071071  相似文献   

6.
We show that for every odd integer p 1 there is an absolute positive constantcp, so that the maximum cardinality of a set of vectors in Rn such that the lp distance between any pair is precisely 1, is at most cp n log n. We prove some upper bounds for other lp norms as well.  相似文献   

7.
We give a very simple and elementary proof of the existence of a weakly compact family of probability measures {Pθ : θ∈θ} representing an important sublinear expectation- G-expectation E[·]. We also give a concrete approximation of a bounded continuous function X(ω) by an increasing sequence of cylinder functions Lip(Ω) in order to prove that Cb(Ω) belongs to the completion of Lip(Ω) under the natural norm E[|·|].  相似文献   

8.
In the paper, we present upper bounds of L p norms of order ( X)-1/2 for all 1 ≤ p ≤ ∞ in the central limit theorem for a standardized random variable (XX)/ √ X, where a random variable X is distributed by the Poisson distribution with parameter λ > 0 or by the standard gamma distribution Γ(α, 0, 1) with parameter α > 0. The research was partially supported by the Lithuanian State Science and Studies Foundation, grant No. T-70/09.  相似文献   

9.
For 0 < α < mn and nonnegative integers n ≥ 2, m ≥ 1, the multilinear fractional integral is defined by
where = (y 1,y 2, ···, y m ) and denotes the m-tuple (f 1,f 2, ···, f m ). In this note, the one-weighted and two-weighted boundedness on L p (ℝ n ) space for multilinear fractional integral operator I α(m) and the fractional multi-sublinear maximal operator M α(m) are established respectively. The authors also obtain two-weighted weak type estimate for the operator M α(m). Supported in Part by the NNSF of China under Grant #10771110, and by NSF of Ningbo City under Grant #2006A610090.  相似文献   

10.
We show that the Lp-approximation order of surface spline interpolation equals m+1/p for p in the range 1 \leq p \leq 2, where m is an integer parameter which specifies the surface spline. Previously it was known that this order was bounded below by m + &frac; and above by m+1/p. With h denoting the fill-distance between the interpolation points and the domain , we show specifically that the Lp()-norm of the error between f and its surface spline interpolant is O(hm + 1/p) provided that f belongs to an appropriate Sobolev or Besov space and that \subset Rd is open, bounded, and has the C2m-regularity property. We also show that the boundary effects (which cause the rate of convergence to be significantly worse than O(h2m)) are confined to a boundary layer whose width is no larger than a constant multiple of h |log h|. Finally, we state numerical evidence which supports the conjecture that the Lp-approximation order of surface spline interpolation is m + 1/p for 2 < p \leq \infty.  相似文献   

11.
We present an equivalence theorem, which includes all known characterizations of the class B p , i.e., the weight class of Ariño and Muckenhoupt, and also some new equivalent characterizations. We also give equivalent characterizations for the classes B p * , B * and RB p , and prove and apply a “gluing lemma” of independent interest.  相似文献   

12.
A set S of vertices in a graph G is a paired-dominating set of G if every vertex of G is adjacent to some vertex in S and if the subgraph induced by S contains a perfect matching. The paired-domination number of G, denoted by , is the minimum cardinality of a paired-dominating set of G. In [1], the authors gave tight bounds for paired-dominating sets of generalized claw-free graphs. Yet, the critical cases are not claws but subdivided stars. We here give a bound for graphs containing no induced P 5, which seems to be the critical case.  相似文献   

13.
The lattice vertex operator algebra VL associated to a positive definite even lattice L has an automorphism of order 2 lifted from –1-isometry of L. The fixed point set VL+ of VL for the automorphism is naturally a vertex operator algebra. We prove that any 0-graded weak VL+-module is completely reducible.Supported by JSPS Research Fellowships for Young Scientists.  相似文献   

14.
In this paper the author first introduce a new concept of L p -dual mixed volumes of star bodies which extends the classical dual mixed volumes. Moreover, we extend the notions of L p intersection body to L p -mixed intersection body. Inequalities for L p -dual mixed volumes of L p -mixed intersection bodies are established and the results established here provide new estimates for these type of inequalities. This work was supported by the Natural Science Foundation of Zhejiang Province of China (Grant No. Y605065) and the Foundation of the Education Department of Zhejiang Province of China (Grant No. 20050392)  相似文献   

15.
We consider the mixed problem,
in a class of Lipschitz graph domains in two dimensions with Lipschitz constant at most 1. We suppose the Dirichlet data, f D , has one derivative in L p (D) of the boundary and the Neumann data, f N , is in L p (N). We find a p 0 > 1 so that for p in an interval (1, p 0), we may find a unique solution to the mixed problem and the gradient of the solution lies in L p . L. Lanzani, L. Capogna and R. M. Brown were supported, in part, by the U.S. National Science Foundation.  相似文献   

16.
With the objective of generating “shape-preserving” smooth interpolating curves that represent data with abrupt changes in magnitude and/or knot spacing, we study a class of first-derivative-based -smooth univariate cubic L 1 splines. An L 1 spline minimizes the L 1 norm of the difference between the first-order derivative of the spline and the local divided difference of the data. Calculating the coefficients of an L 1 spline is a nonsmooth non-linear convex program. Via Fenchel’s conjugate transformation, the geometric dual program is a smooth convex program with a linear objective function and convex cubic constraints. The dual-to-primal transformation is accomplished by solving a linear program.  相似文献   

17.
Let be an n-dimensional compact, possibly with boundary, submanifold in an (n + p)-dimensional space form R n+p (c). Assume that r is even and , in this paper we introduce rth mean curvature function S r and (r + 1)-th mean curvature vector field . We call M to be an r-minimal submanifold if on M, we note that the concept of 0-minimal submanifold is the concept of minimal submanifold. In this paper, we define a functional of , by calculation of the first variational formula of J r we show that x is a critical point of J r if and only if x is r-minimal. Besides, we give many examples of r-minimal submanifolds in space forms. We calculate the second variational formula of J r and prove that there exists no compact without boundary stable r-minimal submanifold with in the unit sphere S n+p . When r = 0, noting S 0 = 1, our result reduces to Simons’ result: there exists no compact without boundary stable minimal submanifold in the unit sphere S n+p .   相似文献   

18.
We investigate the best approximations of sine-shaped functions by constants in the spaces Lp for p < 1. In particular, we find the best approximation of perfect Euler splines by constants in the spaces Lp for certain p(0,1).Translated from Ukrainskyi Matematychnyi Zhurnal, Vol. 56, No. 6, pp. 745–762, June, 2004.  相似文献   

19.
We establish the boundedness properties in L p for a class of integral transformations with respect to an index of hypergeometric functions. In particular, by using the Riesz-Thorin interpolation theorem, we get the corresponding results in L p (R +), 1 p 2, for the Kontorovich-Lebedev, Mehler-Fock, and Olevskii index transforms. An inversion theorem is proved for a general index transformation. The case p=2 is known as the Plancherel-type theory for this class of transformations.__________Published in Lietuvos Matematikos Rinkinys, Vol. 45, No. 1, pp. 127–147, January–March, 2005.  相似文献   

20.
We prove firstly the classification theorem for p-harmonic morphisms between Euclidean domains. Secondly, we show that if is a p-harmonic morphism (p ≥ 2) from a complete Riemannian manifold M of nonnegative Ricci curvature into a Riemannian manifold N of non-positive scalar curvature such that the L q -energy is finite, then is constant, which improve the corresponding result due to G. Choi, G. Yun in (Geometriae Dedicata 101 (2003), 53–59).   相似文献   

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