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1.
In this paper the authors generalize the classic random bipartite graph model, and define a model of the random bipartite multigraphs as follows:let m = m(n) be a positive integer-valued function on n and ζ(n,m;{pk}) the probability space consisting of all the labeled bipartite multigraphs with two vertex sets A ={a1,a2,...,an} and B = {b1,b2,...,bm}, in which the numbers tai,bj of the edges between any two vertices ai∈A and bj∈ B are identically distributed independent random variables with distribution P{tai,bj=k}=pk,k=0,1,2,...,where pk ≥0 and ∞Σk=0 pk=1. They obtain that Xc,d,A, the number of vertices in A with degree between c and d of Gn,m∈ζ(n, m;{pk}) has asymptotically Poisson distribution, and answer the following two questions about the space ζ(n,m;{pk}) with {pk} having geometric distribution, binomial distribution and Poisson distribution, respectively. Under which condition for {pk} can there be a function D(n) such that almost every random multigraph Gn,m∈ζ(n,m;{pk}) has maximum degree D(n)in A? under which condition for {pk} has almost every multigraph G(n,m)∈ζ(n,m;{pk}) a unique vertex of maximum degree in A?  相似文献   

2.
张亚运  吴群英 《数学学报》2018,61(3):403-410
假设{X_n,n≥1}为一列严平稳的NA随机变量,期望为零,方差有限.设S_n=∑_(i=1)~n∑X_i,M_n=max_(1≤i≤n)|S_i|.在适当的条件下,得到了一类NA序列部分和部分和最大值重对数矩收敛的精确渐近性.  相似文献   

3.
张霞  张建华 《数学学报》1936,63(3):221-228
设U=Tri(A,M,B)是三角代数,{φn}n∈N:U→U是一列线性映射.本文利用代数分解的方法,证明了如果对任意U,V∈U且U?V=P为标准幂等元,有φn([U,V]ξi+j=n(φi(U)φj(V)-ξφi(V)φj(U))(ξ≠1),则{φn}n∈N是一个高阶导子,其中φ0=id为恒等映射,U?V=UV+VU为Jordan积,[U,V]ξ=UV-ξVU为ξ-Lie积.  相似文献   

4.
Let X1 and X2 be complex Banach spaces with dimension at least three, A1 and A2 be standard operator algebras on X1 and X2, respectively. For k ≥ 2, let(i1, i2,..., im) be a finite sequence such that {i1, i2,..., im} = {1, 2,..., k} and assume that at least one of the terms in(i1,..., im) appears exactly once. Define the generalized Jordan product T1 o T2 o ··· o Tk= Ti1Ti2··· Tim+ Tim··· Ti2Ti1 on elements in Ai. This includes the usual Jordan product A1A2 + A2A1, and the Jordan triple A1 A2 A3 + A3 A2 A1. Let Φ : A1 → A2 be a map with range containing all operators of rank at most three. It is shown that Φ satisfies that σπ(Φ(A1) o ··· o Φ(Ak)) = σπ(A1 o ··· o Ak) for all A1,..., Ak,where σπ(A) stands for the peripheral spectrum of A, if and only if Φ is a Jordan isomorphism multiplied by an m-th root of unity.  相似文献   

5.
关于Neyman-Pearson基本引理的几个注记   总被引:2,自引:0,他引:2  
本文探讨了Neyman-Pearson基本引理.通过论证总体参数θ只有θ0或θ1两种可能时最优检验功效函数的唯一性,得到了两种假设T1:θ=θ0←→θ=θ1和T2:θ=θ1←→θ=θ0各自对应最优检验的两类错误概率可以互换的结论.  相似文献   

6.
Let G =(V(G), E(G)) be a graph with vertex set V(G) and edge set E(G). For two distinct vertices x and y of a graph G, let RG{x, y} denote the set of vertices z such that the distance from x to z is not equa l to the distance from y to z in G. For a function g defined on V(G) and for U■V(G), let g(U) =∑s∈Ug(s). A real-valued function g : V(G) → [0, 1] is a resolving function of G if g(RG{x, y}) ≥ 1 for any two distinct vertices x, y ∈ V(G). The fractional metric dimension dimf(G)of a graph G is min{g(V(G)) : g is a resolving function of G}. Let G1 and G2 be disjoint copies of a graph G, and let σ : V(G1) → V(G2) be a bijection. Then, a permutation graph Gσ =(V, E) has the vertex set V = V(G1) ∪ V(G2) and the edge set E = E(G1) ∪ E(G2) ∪ {uv | v = σ(u)}. First,we determine dimf(T) for any tree T. We show that 1 dimf(Gσ) ≤1/2(|V(G)| + |S(G)|) for any connected graph G of order at least 3, where S(G) denotes the set of support vertices of G. We also show that, for any ε 0, there exists a permutation graph Gσ such that dimf(Gσ)- 1 ε. We give examples showing that neither is there a function h1 such that dimf(G) h1(dimf(Gσ)) for all pairs(G, σ), nor is there a function h2 such that h2(dimf(G)) dimf(Gσ) for all pairs(G, σ). Furthermore,we investigate dimf(Gσ) when G is a complete k-partite graph or a cycle.  相似文献   

7.
The paper analyses the convergence of sequences of control polygons produced by a binary subdivision scheme of the form
  相似文献   

8.
Let be a sequence of independent equidistributed random vectors with . Let , where and denotes the indicator function of the event in brackets. If, for example, are the gains and are the indicators of success in repetitions of a game of chance, then is the maximal gain along head runs (sequences of successes without interruptions) of length j. We investigate the asymptotic behavior of the values , , where is the length of the longest head run in . We show that the asymptotics of the values depend significantly on the growth rate of j and that these asymptotics vary from the strong noninvariance (as in the ErdsRéenyi law of large numbers) to the strong invariance (as in the CsöorgRévész strong approximation laws). We also consider the Shepp-type statistics. Bibliography: 17 titles.  相似文献   

9.
Consider the following heteroscedastic semiparametric regression model:yi =XTiβ + g(ti) + σiei, 1 < i ≤ n,where {Xi,1 < i < n} are random design points,errors {ei,1 < i < n} are negatively associated (...  相似文献   

10.
Let $A \subset {{\Bbb Z}_N}$, and ${f_A}(s) = \left\{ {\begin{array}{*{20}{l}}{1 - \frac{{|A|}}{N},}&{{\rm{for}}\;s \in A,}\\{ - \frac{{|A|}}{N},}&{{\rm{for}}\;s \notin A.}\end{array}} \right.$ We define the pseudorandom measure of order k of the subset A as follows, Pk(A, N) = $\begin{array}{*{20}{c}}{\max }\\D\end{array}$|$\mathop \Sigma \limits_{n \in {\mathbb{Z}_N}}$fA(n + c1)fA(n + c2) … fA(n + ck)|, where the maximum is taken over all D = (c1, c2, . . . , ck) ∈ ${\mathbb{Z}^k}$ with 0 ≤ c1 < c2 < … < ckN - 1. The subset A ⊂ ${{\mathbb{Z}_N}}$ is considered as a pseudorandom subset of degree k if Pk(A, N) is “small” in terms of N. We establish a link between the Gowers norm and our pseudorandom measure, and show that “good” pseudorandom subsets must have “small” Gowers norm. We give an example to suggest that subsets with “small” Gowers norm may have large pseudorandom measure. Finally, we prove that the pseudorandom subset of degree L(k) contains an arithmetic progression of length k, where L(k) = 2·lcm(2, 4, . . . , 2|$\frac{k}{2}$|), for k ≥ 4, and lcm(a1, a2, . . . , al) denotes the least common multiple of a1, a2, . . . , al.  相似文献   

11.
We analyze polynomials P n that are biorthogonal to exponentials , in the sense that
Here α>−1. We show that the zero distribution of P n as n→∞ is closely related to that of the associated exponent polynomial
More precisely, we show that the zero counting measures of {P n (−4nx)} n=1 converge weakly if and only if the zero counting measures of {Q n } n=1 converge weakly. A key step is relating the zero distribution of such a polynomial to that of the composite polynomial
under appropriate assumptions on {Δ n,j }.   相似文献   

12.
Let \({\{\lambda_j\}^\infty_{j=0}}\) be a strictly increasing sequence of positive numbers with λ0 = 0 and λ1 = 1. We use orthogonal Dirichlet polynomials associated with the arctangent density, to observe that for r > 0, $$\begin{array}{ll}\int^\infty_0\left |\sum\limits^\infty_{n=1}(-1)^{n-1}a_n\lambda^{-irt}_n\right |^2 \frac{dt}{\pi(1 + t^2)}\\ = \sum\limits^\infty_{n=1}(\lambda^{2r}_n - \lambda^{2r}_{n-1})\left |\sum\limits^\infty_{k=n}(-1)^{k-1}\frac{ak}{\lambda^r_k}\right |^2,\end{array}$$ when the right-hand side converges. As a consequence, we obtain uniform mean value estimates, discrete Hilbert type inequalities, and asymptotics as r → ∞ for classes of Dirichlet series.  相似文献   

13.
Let n≥2 be an integer number. In this paper, we investigate the generalized Hyers Ulam- Rassias stability in Banach spaces and also Banach modules over a Banach algebra and a C*-algebra and the stability using the alternative fixed point of an n-dimensional cubic functional equation in Banach spaces:f(2∑j=1^n-1 xj+xn)+f(2∑j=1^n-1 xj-xn)+4∑j=1^n-1f(xj)=16f(∑j=1^n-1 xj)+2∑j=1^n-1(f(xj+xn)+f(xj-xn)  相似文献   

14.
桂兴国  张静 《应用数学》2012,25(3):596-602
本文主要讨论三维Boussinesq方程当扩散系数κ=0时光滑解的爆破准则.利用Littlewood-Paley分解和能量方法证明了如果方程关于水平速度场ū=(u1,u2,0)的水平导数满足▽hū=(1ū,1ū,0)∈L1(0,T;B0∞,∞(R3)).则解(u,θ)可以连续到T1>T.  相似文献   

15.
杨沿奇  陶双平 《数学学报》1936,63(4):381-396
用T和Dγ(0 ≤ γ ≤ 1)分别表示变量核奇异积分和分数次微分算子.T*和T#分别为T的共轭算子及拟共轭算子.利用球调和多项式展式,本文得到了TDγ-DγT和(T*-T#)Dγ在?q,λω(Rn)上的有界性.同时也得到了变量核奇异积分的积T1T2和拟积T1°T2的加权范不等式.  相似文献   

16.
#xa; S_n = \sum\nolimits_{i = 1}^n \xi _i ,\bar S_n = \max _{k \leqslant n} S_k . Assuming that some regularly varying functions majorize and minorize $ F = \frac{1}{n}\sum\nolimits_{i = 1}^n {F_i } $ F = \frac{1}{n}\sum\nolimits_{i = 1}^n {F_i } , we find upper and lower bounds for the probabilities P(Sn > x) and P( $ {\bar S_n } $ {\bar S_n } > x). These bounds are precise enough to yield asymptotics. We also study the asymptotics of the probability that a trajectory {Sk} crosses the remote boundary {g(k)}; i.e., the asymptotics of P(maxk$ \overset{\lower0.5em\hbox{$ \overset{\lower0.5em\hbox{ Matematicheski $ \overset{\lower0.5em\hbox{$ \overset{\lower0.5em\hbox{ Zhurnal, Vol. 46, No. 1, pp. 46–70, January–February, 2005.  相似文献   

17.
We consider a finite XXZ spin chain with periodic boundary conditions and an odd number of sites. It appears that for the special value of the asymmetry parameter = –1/2, the ground state of this system described by the Hamiltonian has the energy E 0 = –3N/2. Although the ground state is antiferromagnetic, we can find the corresponding solution of the Bethe equations. Specifically, we can explicitly construct a trigonometric polynomial Q(u) of degree n = (N–1)/2, whose zeros are the parameters of the Bethe wave function for the ground state of the system. As is known, this polynomial satisfies the Baxter TQ equation. This equation also has a second independent solution corresponding to the same eigenvalue of the transfer matrix T. We use this solution to find the derivative of the ground-state energy of the XXZ chain with respect to the crossing parameter . This derivative is directly related to one of the spin–spin correlators, which appears to be . In turn, this correlator gives the average number of spin strings for the ground state of the chain, . All these simple formulas fail if the number N of chain sites is even.  相似文献   

18.
19.
Let A 0, ... , A n−1 be operators on a separable complex Hilbert space , and let α0,..., α n−1 be positive real numbers such that 1. We prove that for every unitarily invariant norm,
for 2 ≤ p < ∞, and the reverse inequality holds for 0 < p ≤ 2. Moreover, we prove that if ω0,..., ω n−1 are the n roots of unity with ω j = e ij/n , 0 ≤ jn − 1, then for every unitarily invariant norm,
for 2 ≤ p < ∞, and the reverse inequalities hold for 0 < p ≤ 2. These inequalities, which involve n-tuples of operators, lead to natural generalizations and refinements of some of the classical Clarkson inequalities in the Schatten p-norms. Extensions of these inequalities to certain convex and concave functions, including the power functions, are olso optained.   相似文献   

20.
In this paper it is studied that the generated theory of wave recursive interpolation of uniform T-subdivi-ston scheme include wave parameter.The paper analyses the convergence of sequences of control polygons produced by wave recursive interpolation T-subdivision scheme of the formj=l,2,…,T-1;m=O,l,…,nTk;k=0,l,2,…,and differentiability of the limit curve.  相似文献   

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