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1.
陈夏 《应用概率统计》2006,22(4):337-346
本文提出了$\sigma(u)$的一种改进的估计$\wh\sigma_n(u)$, 在一定的条件下证明了$\sup\limits_{u}|\wh\sigma_n(u)-\sigma(u)|$相对于[1]中的估计以更快的速度依概率收敛于0, 并修正了定义区间.  相似文献   

2.
采用样本标准差$s$、$s/c_4$、$\ol{R}/d_2$以及MVA分析后的$\wh{\sigma}_{\text{TOTAL}}$分别估计总体标准差,介绍了相应的$\wh{C}_p$和$\wh{C}_{pk}$以及$C_p$的置信区间,分析了每种标准差估计方法的特点, 结合案例进行比较研究.  相似文献   

3.
该文在弱双代数$H$上给出了扭曲积$(H^\sigma,\cdot_\sigma)$成为弱双代数的充分必要条件.设$[B, H, \tau]$是一个弱斜配对, 并且$\tau$可逆,则在某个条件下弱双交叉积$B\bowtie_\tau H$是一个弱双代数. 如果$(B,H, \sigma)$是弱相关Long双代数, 并且$\sigma$可逆,则弱双交叉积$B^{OP}\bowtie_\sigma H$可以被构造. 它的乘法是:$(x\otimes h)(y\otimes g)=\Sigma\sigma(y_1, h_1)y_2x\otimes h_2g\sigma^{-1}(y_3, h_3),$ 特别地, 如果$(B, H,\sigma)$是相关Long双代数, 则$(B^{OP \bowtie_\sigma H,\beta)$是Long双代数当且仅当对任意$b, d\in B^{OP}; g, \ell\in H$,$\Sigma\sigma^{-1}(b, g_2\ell)\sigma(d, g_1)=\Sigma\sigma^{-1}(b,\ell g_1)\sigma(d, g_2),$ 其中$B$为$H$的子Hopf代数,$\beta$定义为$\beta(b\bowtie_\sigma h\otimes c\bowtie_\sigma g)=\varepsilon_H(h)\varepsilon_{B^{OP}}(c)\sigma^{-1}(b, g).$ 对于Sweedler 4维Hopf代数$H$, 作者给出一个例子说明:此弱双交叉积$(B^{OP}\bowtie_\sigma H, \beta)$不仅是一个Long双代数,而且是一个非可换和非余可换的8维Hopf代数. 最后, 设$B,H$都是弱双代数, $\sigma: B\otimes H\rightarrow k$是一个线性映射, 作者给出了$(B,\sigma,\leftharpoonup, \Delta_B)$是弱相关右$(H, B)$ -重模代数的充分必要条件.  相似文献   

4.
本文研究应力服从一类嵌套多元指数分布, 强度服从指数分布的应力---强度结构可靠度模型.分别在强度参数未知、应力参数已知和强度参数已知、应力参数未知的情况下给出了结构可靠度$P_{A}$的估计$\wh{P}_{A1}$和$\wh{P}_{A2}$,并讨论了它们的渐近性质,而且获得了$P_{A}$的近似置信区间.最后对这两种情况下模型结构可靠度的估计$\wh{P}_{A1}$和$\wh{P}_{A2}$进行了随机模拟,随机模拟结果令人满意.  相似文献   

5.
Let X and Z be two reflexive Banach spaces, U\in Z and b(\cdot,\cdot):[t_0,T]*U\rightarrow X continuous. Suppose $x(t)\equiv x(t,u(\cdot))$ is a function from [t_0, T] into X , satisfying the distrbnted parameter system $dx(t)\dt=A(t)x(t)+b(t,u(t)),t_0+\int_t_0^T {+r(t,u(t))dt}$. We have proved the following theorem. Theorem. Suppose u^*(\cdot) is the optimal control function, $x^*(t)=x(t,u^*(\cdot))$ and $\psi (t)=-U'(T,t)Q_1x^*(T)-\int_t^T{U'(\sigma,t)Q(\sigma)x^*(\sigma)d\sigma}$, then the maximum principle $<\psi(t),b(t,u^*(t))>-1/2r(t,u^*(t))=\mathop {\max }\limits_{u \in U} {\psi (t),b(t,u)>-1/2r(t,u)}$ (16) holds for almost all t on [t_0, T ].  相似文献   

6.
假设总体$X$服从两点均匀分布, 即$\pr(X=x_1)=\pr(X=x_2)=1/2$, 但是随机变量$X$的取值$x_1$和$x_2$是未知的\bd 在区间截断的情况下, 利用样本获得了$x_1$和$x_2$估计量$\wh{x}_1$和$\wh{x}_2$, 并给出了估计量$\wh{x}_1$和$\wh{x}_2$的收敛速度$o(n^{-1/3+\xs})$.  相似文献   

7.
徐新冬  耿建生 《中国科学A辑》2008,38(11):1235-1246
考虑高维的具有周期边值条件的非线性梁方程 $u_{tt} +\Delta^2u+\sigma u+f(u)=0,$ 其中$f(u)$为实解析的函数, 且在$u=0$附近具有形式$f(u)=u^3+$h.o.t; $\sigma$ 为一个正常数. 对任意给定的$\sigma>0$, 通过证明相应的无穷维动力系统的有限维不变环面的存在性, 得到梁方程的一族具有小振幅的拟周期解的存在性与线性稳定性.  相似文献   

8.
该文讨论了如下具有退化粘性的非齐次双曲守恒律方程的Cauchy问题$\left\{\begin{array}{l} u_t+f(u)_x=a^2t^\alpha u_{xx}+g(u),\ \ \ x\in{\bf R},\ \ \ t>0,\\u(x,0)=u_0(x) \in L^\infty({\bf R}).\end{array}\right.\eqno{({\rm I})}$其中$f(u), g(u)$是${\bf R}$上的光滑函数, $a>0, 0<\alpha<1$均为常数.在此条件下, 作者首先给出了Cauchy问题(I)的局部解的存在性, 再利用极值原理获得了解的$L^{\infty}$估计, 从而证明了Cauchy问题(I)整体光滑解的存在性.  相似文献   

9.
对于混合分布模型$H=\lambda F+(1-\lambda)G$, 构造了在右随机截断下混合分布系数$\lambda$的估计量$\wh{\lambda}$, 并证明了$\wh{\lambda}$的渐进正态性.  相似文献   

10.
本文中我们考虑下面的系统 $[\frac{{dx(t)}}{{dt}} = L({x_i}) + Rf(\sigma (t))\]$ $[\sigma (t) = Cx(t)\]$ 以及 $[\frac{{dx(t)}}{{dt}} = L({x_i}) + Rf(\sigma (t))\]$ $[\frac{{d\xi (t)}}{{dt}} = f(\sigma (t)),\sigma (t) = Cx(t) + D\xi (t)\]$ 其中x,f是n维向量,\sigma,\xi 是m维向量,C、D是m*n矩阵,R是n*m矩阵,m>1. 我们引入了系统的广义H-绝对稳定性,并给出了系统(1)(2)的广义H-绝对稳定性的充分判据。本文中我们推广和简化了文[1,2]中的方法。对非线性项f(\sigma)去掉了f_j仅依赖于\sigma_j的限制。  相似文献   

11.
本文研究一类二阶齐次线性微分方程f"+A_1(z)e~(P(z))f'+A_0(z)e~(Q(z))f=0,解的增长性,其中P(z)=az~n,Q(z)=bz~n,ab≠0,a=cb(c1),A_j(z)(j=0,1)是非零多项式,证明了该方程的每个非零解满足σ(f)=∞并且σ_2(f)=n.  相似文献   

12.
Let H1, H2 and H3 be infinite dimensional separable complex Hilbert spaces. We denote by M(D,V,F) a 3×3 upper triangular operator matrix acting on Hi +H2+ H3 of theform M(D,E,F)=(A D F 0 B F 0 0 C).For given A ∈ B(H1), B ∈ B(H2) and C ∈ B(H3), the sets ∪D,E,F^σp(M(D,E,F)),∪D,E,F ^σr(M(D,E,F)),∪D,E,F ^σc(M(D,E,F)) and ∪D,E,F σ(M(D,E,F)) are characterized, where D ∈ B(H2,H1), E ∈B(H3, H1), F ∈ B(H3,H2) and σ(·), σp(·), σr(·), σc(·) denote the spectrum, the point spectrum, the residual spectrum and the continuous spectrum, respectively.  相似文献   

13.
可迹图即为一个含有Hamilton路的图.令$N[v]=N(v)\cup\{v\}$, $J(u,v)=\{w\in N(u)\cap N(v):N(w)\subseteq N[u]\cup N[v]\}$.若图中任意距离为2的两点$u,v$满足$J(u,v)\neq \emptyset$,则称该图为半无爪图.令$\sigma_{k}(G)=\min\{\sum_{v\in S}d(v):S$为$G$中含有$k$个点的独立集\},其中$d(v)$表示图$G$中顶点$v$的度.本论文证明了若图$G$为一个阶数为$n$的连通半无爪图,且$\sigma_{3}(G)\geq {n-2}$,则图$G$为可迹图; 文中给出一个图例,说明上述结果中的界是下确界; 此外,我们证明了若图$G$为一个阶数为$n$的连通半无爪图,且$\sigma_{2}(G)\geq \frac{2({n-2})}{3}$,则该图为可迹图.  相似文献   

14.
一类缺项算子矩阵的四类点谱的扰动   总被引:1,自引:0,他引:1  
有界线性算子的点谱可进一步细分为4类,分别为$\sigma_{p1}$, $\sigma_{p2}$, $\sigma_{p3}$ 和$\sigma_{p4}$.设 $H, K$为无穷维可分的Hilbert空间,用$M_C$表示$2\times 2$上三角算子矩阵$\left(\begin{array}{cc} A & C \\ 0 & B \\ \end{array} \right)$,对于给定的 $A\in B(H),~B\in B(K)$,描述了集合$\bigcap\limits_{C\in B(K,H)}\sigma_{p1}(M_C)$, $\bigcap\limits_{C\in B(K,H)}\sigma_{p2}(M_C)$, $\bigcap\limits_{C\in B(K,H)}\sigma_{p3}(M_C)$和$\bigcap\limits_{C\in B(K,H)}\sigma_{p4}(M_C)$.  相似文献   

15.
In this paper, we have studied the separation for the biharmonic Laplace-Beltrami differential operator\begin{equation*}Au(x)=-\Delta \Delta u(x)+V(x)u(x),\end{equation*}for all $x\in R^{n}$, in the Hilbert space $H=L_{2}(R^{n},H_{1})$ with the operator potential $V(x)\in C^{1}(R^{n},L(H_{1}))$, where $L(H_{1})$ is the space of all bounded linear operators on the Hilbert space $H_{1}$, while $\Delta \Delta u$\ is the biharmonic differential operator and\begin{equation*}\Delta u{=-}\sum_{i,j=1}^{n}\frac{1}{\sqrt{\det g}}\frac{\partial }{{\partial x_{i}}}\left[ \sqrt{\det g}g^{-1}(x)\frac{\partial u}{{\partial x}_{j}}\right]\end{equation*}is the Laplace-Beltrami differential operator in $R^{n}$. Here $g(x)=(g_{ij}(x))$ is the Riemannian matrix, while $g^{-1}(x)$ is the inverse of the matrix $g(x)$. Moreover, we have studied the existence and uniqueness Theorem for the solution of the non-homogeneous biharmonic Laplace-Beltrami differential equation $Au=-\Delta \Delta u+V(x)u(x)=f(x)$ in the Hilbert space $H$ where $f(x)\in H$ as an application of the separation approach.  相似文献   

16.
2×2阶上三角型算子矩阵的Moore-Penrose谱   总被引:1,自引:1,他引:1  
设$H_{1}$和$H_{2}$是无穷维可分Hilbert空间. 用$M_{C}$表示$H_{1}\oplusH_{2}$上的2$\times$2阶上三角型算子矩阵$\left(\begin{array}{cc} A & C \\ 0 & B \\\end{array}\right)$. 对给定的算子$A\in{\mathcal{B}}(H_{1})$和$B\in{\mathcal{B}}(H_{2})$,描述了集合$\bigcap\limits_{C\in{\mathcal{B}}(H_{2},H_{1})}\!\!\!\sigma_{M}(M_{C})$与$\bigcup\limits_{C\in{\mathcal{B}}(H_{2},H_{1})}\!\!\!\sigma_{M}(M_{C})$,其中$\sigma_{M}(\cdot)$表示Moore-Penrose谱.  相似文献   

17.
A spanning tree with no more than 3 leaves is called a spanning 3-ended tree.In this paper, we prove that if G is a k-connected(k ≥ 2) almost claw-free graph of order n and σ_(k+3)(G) ≥ n + k + 2, then G contains a spanning 3-ended tree, where σk(G) =min{∑_(v∈S)deg(v) : S is an independent set of G with |S| = k}.  相似文献   

18.
In this paper, we prove that two-parameter Volterra multifractional process can be approximated in law in the topology of the anisotropic Besov spaces by the family of processes{B_n(s,t)},n∈N defined by B_n(s,t)=∫_0~s ∫_0~tk_(a(s))(s,u)K_(β(t))(t,u)θ_(n(u,v))dudv,here {θ_n(u, v)}n∈N is a family of processes, converging in law to a Brownian sheet as n→∞,based on the well known Donsker's theorem.  相似文献   

19.
Let be a contraction on a Banach space and the Banach algebra generated by . Let be the unitary spectrum (i.e., the intersection of with the unit circle) of . We prove the following theorem of Katznelson-Tzafriri type: If is at most countable, then the Gelfand transform of vanishes on if and only if

  相似文献   


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