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1.
给出了如下形式的弦截切线法预估校正(P.C.)格式P(预估):ψ1(xn)=xn-f(xn)/(f(xn,x(n-1))),ψ2(xn)=xn-f(xn)/(f(xn,ψ1(xn)))C(校正):xn+1=ψ2(xn)-f(ψ2(xn))/(f(ψ2(xn),ψ1(xn))+f(ψ2(xn),xn)-f(ψ1(xn),xn))证明了它的收敛阶为3+√5.  相似文献   

2.
Let I={(x,x)|∈G}, δ∈P(G~2),I≤δ,δ=δ~(-1),G_i=max{E|EG, E~2≤δ} do notbe reduced to single point; gG~2×W, DW, ψ=gD. Ifψ∨ψ~(-1)∨I≤δ,then G_i∩(G_iψ∪ψG_i)≠φIf (ψ∧ψ~(-1))1ψ∨I≤δ, then G_i∩G_iψ∩ψG_i≠φ.If (ψ~t∧ψ(-t)∧ψ(-t))∨I≤δ,then there exist positive integers m, n, such that G_i∩G_iψ~(m)∩ψ~(n)G_i≠φ, whereψ~t is the transitive closure of ψ, and ψ~(m) is the composition of m times of ψ it-  相似文献   

3.
本文研究Jaulent-Miodek族的对易表示,在无反射位势的特征函数表示:即 q=-〈ψ_2,ψ_2〉,r=(Aψ_2,ψ2); (q,r)~T≡f(ψ),ψ≡(ψ_1,ψ_2)~T所诱导的约束条件下,Jaulent-Miodek族的Lax对的空间部分被非线性化为一个完全可积系统(R~(2N),dψ_1∧dψ_2,H=(?)_0),其中(?)_0=i〈Aψ_1,ψ_2〉+1/2〈ψ_1,ψ_2〉〈Aψ_2,ψ_2〉.时间部分的非线性化导出它的N-对合系{(?)_m},相容方程组((?)_0),((?)_m)的对合解被f映为第m个Jaulent-Miodek方程的解。  相似文献   

4.
讨论了三类包含Euler函数的方程x-ψ(x)=2~(ω(x)),x-ψ(ψ(x))=2~(ω(x))与ψ(x~k)=2~(ω(x~k))的可解性,利用初等方法给出这三类方程的所有正整数解,其中ψ(x)为Euler函数,ω(x)为x的相异素因子个数.  相似文献   

5.
本文是文[6]的继续,研究模糊保凸映射,用子基线段给出其特征定义1 设ψ是fts(x,J)的闭子基,非空模糊集c称为ψ-闭(或ψ-凸)如果有族■■ψ使得c=∩■。记H(X,ψ)是所有ψ-闭模糊集的全体。F-映射f:(X,J)→(Y,U)称为关于它们的闭子基ψ和ψ的F-保凸映射(简记F—cp映射)如果■T∈  相似文献   

6.
给定数据(x1,y1),(x2,y2),…,(xm,ym),考虑一般的损失函数ψ(y-f(x))下,当ψ(z)连续及ξ1=ψ(y1-f(x1)),ξ2=ψ(y2-f(x2)),…,ξm=ψ(ym-f(xm))是一个负相关序列时,本文研究了样本误差估计问题.  相似文献   

7.
周泽华  方中山 《数学进展》2004,33(6):691-696
设D是复空间C中的单位圆盘,ψ是D到自身的一个全纯映射,ψ(z)是D上的全纯函数,0<α<1.本文给出了单位圆盘中Lipschitz空间Lipa(D)上由ψ和ψ诱导的加权复合算子Wψ,ψ的有界性及紧性的充要条件.  相似文献   

8.
设D={z∈C:|z|1}是复平面上的单位圆盘,H(D)表示D上的所有解析函数的集合,ψ_1,ψ_2∈H(D),n是一个非负整数,φ是D到D的一个解析自映射,μ是一个权函数.研究从混合模空间到Zygmund-型空间的积型算子T_(ψ_1,ψ_2,φ)~n的有界性和紧性特征,其中T_(ψ_1,ψ_2,φ)~nf(z)=ψ_1(z)f~((n))(φ(z))+ψ_2(z)f~((n+1))(φ(z)),f∈H(D).  相似文献   

9.
张学军 《数学杂志》2005,25(4):361-367
本文将刻划从小Bloch型空间β0p到β0q(0<p,q<∞)上加权复合算子Tψ,ψ的有界性和紧性.同时得到了Tψ,ψ是Bloch型空间βp到βq(p>1,0≤q≤1)有界算子的充要条件以及Tψ,ψ是Bloch型空间βp到βq(0≤p,q<∞)紧算子的充要条件.  相似文献   

10.
Bergman空间和q-Bloch空间之间的复合算子   总被引:4,自引:0,他引:4  
本文讨论了Bergman空间和q-Bloch空间(小q-Bloch空间)之间的复合算子C(ψ)的有界性和紧性特征,得到了以下结论(1)C(ψ)是q-Bloch空间(小q-Bloch空间)到Bergman空间的有界算子或紧算子之充要条件;(2)C(ψ)是Bergman空间到q-Bloch空间的有界算子或紧算子之充要条件;(3)C(ψ)是Bergman空间到小q-Bloch空间的有界算子或紧算子之充要条件,还给出了算子C0的范数估计,此处C0(f)(z)=fo(ψ)(z)-f((ψ)(0)).  相似文献   

11.
设φ(z)=(φ1(z),…,φ_n(z))是D~n到自身的一个全纯映射,ψ(z)是D~n上的全纯函数,其中D~n是C~n中的单位多圆柱.研究了单位多圆柱上Bloch型空阊之间的加权复合算子ψC_φ的本性范数,并给出了其上下界估计.  相似文献   

12.
程俊芳  李登峰 《数学学报》2008,51(5):877-888
设E=■或■,■(x)∈L~2(R~2)且■_(jk)(x)=2■(E~jx-k),其中j∈Z,k∈Z~2.若{■_(jk)|jJ∈Z,k∈Z~2}构成L~2(R~2)的紧框架,则称■(x)为E-紧框架小波.本文给出E-紧框架小波是MRA E-紧框架小波的一个充要条件,即E紧框架小波■来自多尺度分析当且仅当线性空间F_■(ξ)的维数为0或1,其中F_■(ξ)=■(ξ)|j■1},■_j(ξ)={■((E~T)~j(ξ+2kπ))}_(k∈EZ~2,j■1。  相似文献   

13.
带接种疫苗和二次感染的年龄结构MSEIR流行病模型分析   总被引:1,自引:0,他引:1  
本文讨论带二次感染和接种疫苗的年龄结构MSEIR流行病模型。在常数人口规模的假设下,运用微分方程和积分方程中的理论和方法,得到一个与接种疫苗策略ψ有关的再生数R(ψ)的表达式,证明了当R(ψ)<1时,无病平衡态是局部渐近稳定的;当R(ψ)>1时,无病平衡态是不稳定的,此时存在一个地方病平衡态,并且证明当R(0)<1时,无病平衡态是全局渐近稳定的。  相似文献   

14.
By using the method of dynamical systems to Mikhailov-Novikov-Wang Equation, through qualitative analysis, we obtain bifurcations of phase portraits of the traveling system of the derivative $\phi(\xi)$ of the wave function $\psi(\xi)$. Under different parameter conditions, for $\phi(\xi)$, exact explicit solitary wave solutions, periodic peakon and anti-peakon solutions are obtained. By integrating known $\phi(\xi)$, nine exact explicit traveling wave solutions of $\psi(\xi)$ are given.  相似文献   

15.
Let F be a family of meromorphic functions in D,and let Ψ(≠0) be a meromorphic function in D all of whose poles are simple.Suppose that,for each f ∈F,f≠0 in D.If for each pair of functions {f,g}(?) F,f' and g' share Ψ in D,then F is normal in D.  相似文献   

16.
Let ${\|\cdot\|_{\psi}}$ be the absolute norm on ${\mathbb{R}^2}$ corresponding to a convex function ${\psi}$ on [0, 1] and ${C_{\text{NJ}}(\|\cdot\|_{\psi})}$ its von Neumann–Jordan constant. It is known that ${\max \{M_1^2, M_2^2\} \leq C_{\text{NJ}}(\| \cdot \|_{\psi}) \leq M_1^2 M_2^2}$ , where ${M_1 = \max_{0 \leq t \leq 1} \psi(t)/ \psi_2(t)}$ , ${M_2 = \max_{0\leq t \leq 1} \psi_2(t)/ \psi(t)}$ and ${\psi_2}$ is the corresponding function to the ? 2-norm. In this paper, we shall present a necessary and sufficient condition for the above right side inequality to attain equality. A corollary, which is valid for the complex case, will cover a couple of previous results. Similar results for the James constant will be presented.  相似文献   

17.
The author studies the life span of classical solutions to the following Cauchy problem $\[B \simeq Ma{t_m}(kD)\]$, $t=0:u=\epsilon\phi(x),u_t=\epsilon\psi(x),x\in R^2$ where $\phi,\psi\in C_0^\infinity(R^2)$ and not both identically zero,$\[\square = \partial _t^2 - \partial _1^2 - \partial _2^2,p \geqslant 2\]$ is a real number and $\epsilon > 0$ is a small parameter, and obtains respectively upper and lower bounds of the same order of magnitude for the life span for $2\leq p \leq p_0$, where $p_0$ is the positive root of the quadratic $X^2-3X-2=0$.  相似文献   

18.
We establish rather weak conditions on under which the small scale affine system spans . The conditions are that the periodization of |ψ| be locally in Lp, that , and that the dilation matrices aj are expanding, meaning . The periodization of ψ need not be constant; that is, the integer translates need not form a partition of unity. The proof involves explicitly approximating an arbitrary function f using a linear combination of the , with the coefficients in the linear combination being local average values of f .  相似文献   

19.
We study large time asymptotic behavior of solutions to the periodic problem for the nonlinear Burgers type equation
$ \left\{ {l} \psi_{t}=\psi_{xx}+\lambda \psi +\psi \psi_{x},\quad x\in \Omega, \quad t >0 , \\ \psi (0,x)=\widetilde{\psi}(x), \quad x\in \Omega, \right. $ \left\{ \begin{array}{l} \psi_{t}=\psi_{xx}+\lambda \psi +\psi \psi_{x},\quad x\in \Omega, \quad t >0 , \\ \psi (0,x)=\widetilde{\psi}(x), \quad x\in \Omega, \end{array} \right.  相似文献   

20.
We derive the optimal decay rates of solution to the Cauchy problem for a set of nonlinear evolution equations with ellipticity and dissipative effects
$\left\{ \begin{aligned} & \psi t = - (1 - \alpha )\psi - \theta _{x} + \alpha \psi _{{xx}} , \\ & \theta _{t} = - (1 - \beta )\theta + \nu \psi _{x} + 2\psi \theta _{x} + \alpha \theta _{{xx}} , \\ \end{aligned} \right.$\left\{ \begin{aligned} & \psi t = - (1 - \alpha )\psi - \theta _{x} + \alpha \psi _{{xx}} , \\ & \theta _{t} = - (1 - \beta )\theta + \nu \psi _{x} + 2\psi \theta _{x} + \alpha \theta _{{xx}} , \\ \end{aligned} \right.  相似文献   

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