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1.
In this paper, 2-microlocal Herz type Besov and Triebel-Lizorkin spaces with variable exponents are introduced for the first time. Then, we give characterizations of these spaces by so-called Peetre's maximal functions. Further, the atomic and molecular decompositions of these spaces are obtained. Finally, using the characterizations of the spaces by local means and molecular decomposition we obtain the wavelet characterizations.  相似文献   

2.
綦明男  刘三阳 《应用数学》2005,18(3):345-351
下面的问题被称为n个外观不可区分硬币的分组测试问题,每个硬币可以是伪硬币或是标准硬币.本文所涉及的问题是:已知一个由n个硬币组成的集合中有两个伪(较重的)硬币,用一台天平以最小的称重次数,从这n个硬币组成的集合中探测出两个伪(较重的)硬币. 我们构造了找出两个伪(较重的)硬币的两个算法,并且这两个算法是最优的.  相似文献   

3.
In Kolwankar and Lévy Véhel, new functional spaces, denoted $K^{s,s}_{x_0}$, were introduced. These spaces characterize the fine local regularity of functions, much in the spirit of 2-microlocal spaces $C^{s,s}_{x_0}$. In contrast with $\C^{s,s}_{x_0}$ spaces, however, $K^{s,s}_{x_0}$ spaces are defined through simple estimations on the pointwise values of the functions. In this work, we generalize the definition of $K^{s,s}_{x_0}$ spaces and prove the equality $C^{s,s}_{x_0}=K^{s,s}_{x_0}$ for $s+s>0$, $s>0$. Using this result, we propose an algorithm able to estimate a part of the 2-microlocal frontier. Experiments on sampled data show that reasonable accuracy is achieved even for difficult functions such as continuous but nowhere differentiable ones. As a by-product, robust estimators of both the pointwise and the local exponents are obtained.  相似文献   

4.
In this article, we propose a general model for some chirp-like signals. The analytical structure of these chirps is given in the form |x|sg(x/|x|1+β), wheregis aLpindefinitely oscillating function like sin(x). Under suitable assumptions, we achieve a characterization of the chirps by means of their wavelet transforms.  相似文献   

5.
6.
SomeResultsConcerningHereditaryAlgebras¥LuYeguang(Hefeiof,InstituteofEconomyandTechnology)Abstract:Inthispeper,theAlprin'scou...  相似文献   

7.

We give lower and upper bounds on both the Lyapunov exponent and generalised Lyapunov exponents for the random product of positive and negative shear matrices. These types of random products arise in applications such as fluid stirring devices. The bounds, obtained by considering invariant cones in tangent space, give excellent accuracy compared to standard and general bounds, and are increasingly accurate with increasing shear. Bounds on generalised exponents are useful for testing numerical methods, since these exponents are difficult to compute in practice.

  相似文献   

8.
Let P(z) be a polynomial of degree n having no zeros in |z|< 1, then for every real or complex number β with |β|≤ 1, and |z|=1, R ≥ 1, it is proved by Dewan et al. [4] that ︱P(Rz)+ β( R+1/2 )n P(z)︱≤ 1 /2 { (︱Rn + β(R+1/2 )n︱+︱1+ β (R + 1 /2 )n︱) max |z|=1 |P(z)︱-(︱Rn + β (R+1/2 )n︱-︱1+ β(R+1/2 )n︱) min|z|=1 |P(z)︱}.In this paper we generalize the above inequality for polynomials having no zeros in |z|相似文献   

9.
We introduce a concept of multiplicity lattices of 2-multiarrangements, determine the combinatorics and geometry of that lattice, and give a criterion and method to construct a basis for derivation modules effectively.  相似文献   

10.
In this note, we present some detail estimates for the integral ∫L^Ne(x^ky)x^(p-1)dx with general integer k, as well as a singular integral formed from it, which would be useful for some nonlinear additive problems of primes.  相似文献   

11.
Mark Jerrum 《Combinatorica》2006,26(6):733-742
The property of balance (in the sense of Feder and Mihail) is investigated in the context of paving matroids. The following examples are exhibited: (a) a class of “sparse” paving matroids that are balanced, but at the same time rich enough combinatorially to permit the encoding of hard counting problems; and (b) a paving matroid that is not balanced. The computational significance of (a) is the following. As a consequence of balance, there is an efficient algorithm for approximating the number of bases of a sparse paving matroid within specified relative error. On the other hand, determining the number of bases exactly is likely to be computationally intractable. * The work described here was supported by the grant “Sharper analysis of randomised algorithms” from the UK Engineering and Physical Sciences Research Council.  相似文献   

12.
If J is an analytic, saturated gambling house with compact sections, and we show that there exists a (submarkovian) borel kernel P permitted in J such that μ = λP. If is a proper submarkovian resolvent on a Lusin space X, we study the regularity of the reduite RAs of an excesive function s on a set AX.  相似文献   

13.
引入二对共轭指数,应用权函数的方法,给出一个新的有最佳常数因子并在全平面积分的Hilbert型不等式,同时考虑了对应的等价式.  相似文献   

14.
设f(z)是一个复平面上的亚纯函数,c是一个非零有穷复数,a(z)是f(z)的一个小函数,本文研究f(z)-a(z),f(z + c) - a(z)及Δncf(z)-a(z)(n ∈N+)的零点收敛指数与f(z)的级之间的关系.由此改进了涉及导数与差分的亚纯函数值分布的一些相关结果.  相似文献   

15.
Invention of wavelets and fractals have revolutionized several areas of emerging technologies, especially image processing and scientific computing. The iterated function system [2-4,13,17,18,20,25,26,29], inverse problem of images [5,14-16] and wavelet-based numerical methods [6,7,10,19,22,23] are basic in-gredients of these exciting developments. The iterated function system and the collage theorem are among the basic mathematical tools which are consequences of the Banach contraction fixed point theorem. In one of the sections of this paper we have generalized these two theorems applying a generalization of the Banach contraction fixed point theorem due to Edelstein [11]. In the other section we have studied the inverse problem of images by the iterative function system with grey-level in the context of Besov space, extending a result of Forte and Vrscay [16].  相似文献   

16.
Exponents of 2-coloring of symmetric digraphs   总被引:1,自引:0,他引:1  
A 2-coloring (G1,G2) of a digraph is 2-primitive if there exist nonnegative integers h and k with h+k>0 such that for each ordered pair (u,v) of vertices there exists an (h,k)-walk in (G1,G2) from u to v. The exponent of (G1,G2) is the minimum value of h+k taken over all such h and k. In this paper, we consider 2-colorings of strongly connected symmetric digraphs with loops, establish necessary and sufficient conditions for these to be 2-primitive and determine an upper bound on their exponents. We also characterize the 2-colored digraphs that attain the upper bound and the exponent set for this family of digraphs on n vertices.  相似文献   

17.
<正>In mathematics,a power is represented with a base number and an exponent.The base number tells what number is being multiplied.The exponent,a small number written above and to the right of the base number,tells how many times the base number is being multiplied.Today we will talk about  相似文献   

18.
Here introduced and studied are two formulaic classes consisting of various combinatorial algebraic identities and series summation formulas.The basic ideas include utilizing properly the-operator and Stirling numbers for some series transformations.A variety of classic formulas and remarkable identities are shown to be the members of the classes.  相似文献   

19.
The analytic concepts of martingale type p and cotype q of aBanach space have an intimate relation with the geometric conceptsof p-concavity and q-convexity of the space under consideration,as shown by pisier. In particular, for a banach space X, havingmartingale type p for some p > 1 implies that X has martingalecotype q for some q < . The generalisation of these concepts to linear operators wasstudied by the author, and it turns out that the duality aboveonly holds in a weaker form. An example is constructed showingthat this duality result is best possible. So-called random martingale unconditionality estimates, introducedby Garling as a decoupling of the unconditional martingale differences(UMD) inequality, are also examined. It is shown that the random martingale unconditionality constantof for martingales of length n asymptotically behaves like n. This improves previous estimatesby Geiss, who needed martingales of length 2n to show this asymptotic.At the same time the order in the paper is the best that canbe expected.  相似文献   

20.
We consider generalized exponents of a finite reflection group acting on a real or complex vector space V. These integers are the degrees in which an irreducible representation of the group occurs in the coinvariant algebra. A basis for each isotypic component arises in a natural way from a basis of invariant generalized forms. We investigate twisted reflection representations (V tensor a linear character) using the theory of semi-invariant differential forms. Springer’s theory of regular numbers gives a formula when the group is generated by dim V reflections. Although our arguments are case-free, we also include explicit data and give a method (using differential operators) for computing semi-invariants and basic derivations. The data give bases for certain isotypic components of the coinvariant algebra.  相似文献   

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