共查询到20条相似文献,搜索用时 109 毫秒
1.
本文给出了广义Dedekind和与Hardy和的定义,研究了广义Dedekind和的算术性质,并把Hardy和表示成广义Dedekind和的形式.提出了广义Subrahmanyam等式和Knopp定理,并给出了证明. 相似文献
2.
本文简要介绍了流程图(程序框图)的组成,详细分析了计算机执行机理和过程,举例讲解了流程图常见题型的解法,特别是提出了机械模拟和模块归纳的思想方法以及四十字口诀,对高中数学的算法教学和复习有一定指导意义和借鉴作用. 相似文献
3.
利用广义p-值和广义置信区间的概念,研究了Panel模型中未知参数的检验和置信区间问题.对于回归系数,分别考虑了单个情形和多个线性无关情形下的检验和置信区间问题,得到了精确检验和置信区间.对于方差分量,研究了其任意线性组合的检验和置信区间问题,建立了精确检验和置信区间.基于广义p-值和广义置信区间,获取精确检验和置信区间的方法具有计算方便、易应用于小样本问题的特点.最后,分别从理论和数值上研究了这些精确检验和置信区间的统计性质. 相似文献
4.
本文研究了混合随机变量序列加权和的收敛性.利用Utev, S.和Peligrad, M不等式得到了混合随机变量序列加权和的收敛性定理及Hajeck-Rènyi型不等式,推广和改进了W.F,Stout,吴群英,J.Hajeck和A.Rènyi.的相应结论. 相似文献
5.
覆盖空间及粗糙集与拓扑的统一 总被引:3,自引:0,他引:3
引入覆盖空间,定义了其邻域、内部、闭包、测度等概念,研究了它们的性质.得出了粗糙集近似空间和拓扑空间都是具体覆盖空间的重要结论,从而用覆盖空间统一了粗糙集和拓扑.利用覆盖空间,得到了粗糙集和拓扑中更深刻的性质,从算子论和集合论的角度丰富和深化了粗糙集与拓扑的内容. 相似文献
6.
2000年,Hwang和Li提出了一个新的智能卡远程用户认证方案,随后Chan和Cheng对该方案进行了成功的攻击.最近Shen,Lin和Hwang针对该方案提出了一种不同的攻击方法,并提供了一个改进方案用于抵御这些攻击.2003年,Leung等认为Shen-Lin-Hwang改进方案仍然不能抵御Chan和Cheng的攻击,他们用改进后的Chang-Hwang攻击方法进行了攻击.文中主要在Hwang-Li方案的基础上,提出了一个新的远程用户认证方案,该方案主要在注册阶段和登录阶段加强了安全性,抵御了类似Chan-Cheng和Chang-Hwang的攻击. 相似文献
7.
为了提高群组通信中密钥管理协议的安全性和执行效率,分析了群组密钥中集中式密钥管理和分布式密钥管理,针对这两类协议的优势和不足,构造了一种群组密钥管理协议,此协议保留了集中式密钥管理中群组服务器,并融入了分布式管理协议的特点,吸取了两者的优点.最后我们对该协议的安全性和有效性进行了分析.结果表明,在安全性得到保证的前提下显著地提高了协议的执行效率. 相似文献
8.
【背景】苏科版八年级数学(上)学生学习了一次函数,学生对一次函数的概念、图像、性质和应用有了一定的认识和理解,尤其对一次函数应用题的数形结合做了重点探究.但在教学性考试中,教师和学生遇到了问题,在探究解决问题的过程中,有了更深的认识和体会. 相似文献
9.
从一个常见的不等式谈起,分析了多种证明方法,运用该不等式推导出了多个重要结论,对不等式进行了扩充和加强,解释了蕴含的意义,显示了该不等式的重要性和深刻性. 相似文献
10.
一类具密度制约SIS模型的全局稳定性和周期性 总被引:1,自引:0,他引:1
研究了一类具密度制约和双线性传染率的S IS传染病模型,考虑到了实际中对易感者和传染者的控制,得到了地方病平衡点的全局渐近稳定性和系统的周期性,并给出了生物学解释和仿真. 相似文献
11.
P. Milnes 《Acta Mathematica Hungarica》2005,109(3):191-213
Summary For real connected nilpotent groups, 7 is the lowest dimension where there are infinitely many non-isomorphic groups, and
also where some groups (indeed, uncountably many) have no discrete cocompact subgroups. In [21] one infinite family <InlineEquation
ID=IE"1"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"2"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"3"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"4"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"5"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"6"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"7"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"8"><EquationSource Format="TEX"><![CDATA[$]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>\mathcal{G}$
of 7-dimensional groups was identified and classified. Discrete cocompact subgroups H were identified for some groups in $\mathcal{G}$
in [10], along with simple quotients of $C^{*}(\mathrm{H})$ and relevant flows $(\mathrm{H}_3,\mathbf{T}^3)$. In this paper,
such H and attributes are determined for more groups in $\mathcal{G}$; in particular, the members of $\mathcal{G}$ that admit
discrete cocompact subgroups are identified precisely. In achieving some of these results, we consider other known ways of
classifying the groups in $\mathcal{G}$, and also the classification of the analogous family of complex groups. 相似文献
12.
Summary Given a real-valued function <InlineEquation ID=IE"3"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"4"><EquationSource
Format="TEX"><![CDATA[<InlineEquation ID=IE"5"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"6"><EquationSource
Format="TEX"><![CDATA[<InlineEquation ID=IE"7"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"8"><EquationSource
Format="TEX"><![CDATA[<InlineEquation ID=IE"9"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"10"><EquationSource
Format="TEX"><![CDATA[$]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>\mu(x,y)$
of bounded variation in the sense of Hardy and Krause on the square $[0, 2\pi]\times [0, 2\pi]$, the sequence <InlineEquation
ID=IE"1"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"2"><EquationSource Format="TEX"><![CDATA[$$]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>
\mu_{m,n}:=\int^{2\pi}_0 \int^{2\pi}_0 e^{i(mx+ny)} \, d_x \, d_y \mu(x,y), \quad (m,n)\in \bZ^2, $$ may be called the sequence
of trigonometric moment constants with respect to $\mu(x,y)$. We discuss the uniqueness of the expression of the sequence
$\{\mu_{m,n}\}$ in terms of the function $\mu(x,y)$. 相似文献
13.
Zbigniew Olszak 《Periodica Mathematica Hungarica》2005,51(2):59-74
Summary Let <InlineEquation ID=IE"1"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"2"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"3"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"4"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"5"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"6"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"7"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"8"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"9"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"10"><EquationSource Format="TEX"><![CDATA[$]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>(M,J,g)$
be a K\"ahler--Norden manifold. Using the notions of the horizontal and vertical lifts, a class of almost complex structures
$\widetilde J$ is defined on the tangent bundle $T\!M$, and necessary and sufficient conditions for such a structure to be
integrable (complex) are described. Next, a class of pseudo-Riemannian metrics $\widetilde g$ of Norden type is defined on
$T\!M$, for which $\widetilde J$ is an antiisometry. Thus, the pair $(\widetilde J,\widetilde g)$ becomes an almost complex
structure with Norden metric on $T\!M$. It is checked whether the structure $(\widetilde J,\widetilde g)$ is K\"ahler--Norden
itself. 相似文献
14.
Summary Recently, Goubin, Mauduit, Rivat and Sárk?zy have given three constructions for large families of binary sequences. In each
of these constructions the sequence is defined by modulo <InlineEquation ID=IE"1"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"2"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"3"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"4"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"5"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"6"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"7"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"8"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"9"><EquationSource Format="TEX"><![CDATA[$]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>p$
congruences where $p$ is a prime number. In this paper the three constructions are extended to the case when the modulus is
of the form $pq$ where $p$, $q$ are two distinct primes not far apart (note that the well-known Blum-Blum-Shub and RSA constructions
for pseudorandom sequences are also of this type). It is shown that these modulo $pq$ constructions also have certain strong
pseudorandom properties but, e.g., the (``long range') correlation of order $4$ is large (similar phenomenon may occur in
other modulo $pq$ constructions as well). 相似文献
15.
Summary Let <InlineEquation ID=IE"1"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"2"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"3"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"4"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"5"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"6"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"7"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"8"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"9"><EquationSource Format="TEX"><![CDATA[$]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>{\cal
{X}}_{n} =(X_1,\ldots,X_n)$ be a random vector. Suppose that the random variables $(X_i)_{1\leq i\leq n}$ are stationary and
fulfill a suitable dependence criterion. Let $f$ be a real valued function defined on $\mathbbm{R}^n$ having some regular
properties. Let ${\cal {Y}}_{n}$ be a random vector, independent of ${\cal {X}}_{n}$, having independent and identically distributed
components. We control $\left|\mathbbm{E}(f({\cal {X}}_{n}))-\mathbbm{E} (f({\cal {Y}}_{n}))\right|$. Suitable choices of
the function $f$ yield, under minimal conditions, to rates of convergence in the central limit theorem, to some moment inequalities
or to bounds useful for Poisson approximation. The proofs are derived from multivariate extensions of Taylor's formula and
of the Lindeberg decomposition. In the univariate case and in the mixing setting the method is due to Rio (1995). 相似文献
16.
C.O. AlvesAna Maria Bertone J.V. Goncalves 《Journal of Mathematical Analysis and Applications》2002,265(1):103-127
We employ variational techniques to study the existence and multiplicity of positive solutions of semilinear equations of the form − Δu = λh(x)H(u − a)uq + u2* − 1 in RN, where λ, a > 0 are parameters, h(x) is both nonnegative and integrable on RN, H is the Heaviside function, 2* is the critical Sobolev exponent, and 0 ≤ q < 2* − 1. We obtain existence, multiplicity and regularity of solutions by distinguishing the cases 0 ≤ q ≤ 1 and 1 < q < 2* − 1. 相似文献
17.
Xiaoming HeWeigao Ge 《Journal of Mathematical Analysis and Applications》2002,268(1):256-265
We establish the existence of at least three positive solutions to the second-order three-point boundary value problem, u″ + f(t, u) = 0, u(0) = 0, αu(η) = u(1), where η: 0 lt; η < 1, 0 < α < 1/η, and f: [0, 1] × [0, ∞) → [0, ∞) is continuous. We accomplish this by making growth assumptions on f which can apply to many more cases than the sublinear and superlinear ones discussed in recent works. 相似文献
18.
V. A. Belonogov 《Algebra and Logic》2005,44(6):357-369
Let P(n) be the set of all partitions of a natural number n. In the representation theory of symmetric groups, for every partition
α ∈ P(n), the partition h(α) ∈ P(n) is defined so as to produce a certain set of zeros in the character table for Sn. Previously, the analog f(α) of h(α) was obtained pointing out an extra set of zeros in the table mentioned. Namely, h(α)
is greatest (under the lexicographic ordering ≤) of the partitions β of n such that χα(gβ) ≠ 0, and f(α) is greatest of the partitions γ of n that are opposite in sign to h(α) and are such that χα(gγ) ≠ 0, where χα is an irreducible character of Sn, indexed by α, and gβ is an element in the conjugacy class of Sn, indexed by β. For α ∈ P(n), under some natural restrictions, here, we construct new partitions h′(α) and f′(α) of n possessing
the following properties. (A) Let α ∈ P(n) and n ⩾ 3. Then h′(α) is identical is sign to h(α), χα(gh′(α)) ≠ 0, but χα(gγ) = 0 for all γ ∈ P(n) such that the sign of γ coincides with one of h(α), and h′(α) < γ < h(α). (B) Let α ∈ P(n), α ≠ α′,
and n ⩾ 4. Then f′(α) is identical in sign to f(α), χα(gf′(α)) ≠ 0, but χα(gγ) = 0 for all γ ∈ P(n) such that the sign of γ coincides with one of f(α), and f′(α) < γ < f(α). The results obtained are
then applied to study pairs of semiproportional irreducible characters in An.
Supported by RFBR grant No. 04-01-00463.
__________
Translated from Algebra i Logika, Vol. 44, No. 6, pp. 643–663, November–December, 2005. 相似文献
19.
Michel Weber 《Periodica Mathematica Hungarica》2005,51(1):119-131
Summary Let <InlineEquation ID=IE"1"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"2"><EquationSource Format="TEX"><![CDATA[<InlineEquation
ID=IE"3"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"4"><EquationSource Format="TEX"><![CDATA[$]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>S_n$,
$n=1,2\dots$ be the sequence of partial sums of independent spin random variables. We show that the distribution value of
the divisors of $S_n$, is intimately related to the Zeta-Riemann function via the functional equation and Theta elliptic functions. 相似文献
20.
该文首先研究具有脉冲的线性Dirichlet边值问题
$\left\{
\begin{array}{ll}
x'(t)+a(t)x(t)=0, t\neq \tau_{k}, \ \Delta x(\tau_{k})=c_{k}x(\tau_{k}),\ \Delta x'(\tau_{k})=d_{k}x(\tau_{k}), \ x(0)=x(T)=0,
\end{array}
\right. (k=1,2\cdots,m)
$
给出该Dirichlet边值问题仅有零解的两个充分条件, 其中$a:[0,T]\rightarrow R$, $c_{k}, d_{k}, k=1,2,$ $\cdots,m$是常数, 该文首先研究具有脉冲的线性Dirichlet边值问题
$$\left\{
\begin{array}{ll}
x'(t)+a(t)x(t)=0, t\neq \tau_{k}, \ \Delta x(\tau_{k})=c_{k}x(\tau_{k}),\ \Delta x'(\tau_{k})=d_{k}x(\tau_{k}), \ x(0)=x(T)=0,
\end{array}
\right. (k=1,2\cdots,m)
$$
给出该Dirichlet边值问题仅有零解的两个充分条件, 其中$a:[0,T]\rightarrow R$, $c_{k}, d_{k}, k=1,2,$ $\cdots,m$是常数, $0<\tau_{1}<\tau_{2}\cdots<\tau_{m}<T$为脉冲时刻. 其次利用上面的线性边值问题仅有零解这个性质和Leray-Schauder度理论, 研究具有脉冲的非线性Dirichlet边值问题
$$\left\{
\begin{array}{ll}
x'(t)+f(t,x(t))=0, t\neq \tau_{k}, \ \Delta x(\tau_{k})=I_{k}(x(\tau_{k})), \ \Delta x'(\tau_{k})=M_{k}(x(\tau_{k})), \ x(0)=x(T)=0
\end{array}
\right. (k=1,2\cdots,m)
$$ 解的存在性和唯一性, 其中 $f\in C([0,T]\times
R,R)$, $I_{k},M_{k}\in C(R, R),k=1,2,\cdots,m$.
该文主要定理的一个推论将经典的Lyaponov不等式比较完美地推广到脉冲系统. 相似文献