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1.
胡克 《数学杂志》1993,13(4):413-418
设f(z)=z+Σanz^n为单位园|z|<1内解析且平均单叶,记其族为M又设{f(z)/z}^λ=1+Σ^∞n=1Dn(λ),λ>0,本文说明了:定理一 若f∈M,λ>0,则:Σ^∞k=1{||Dk(λ)|-|Dk-1(λ)||/dk(λ)}^2≤An,n=2,3,…其中A为绝对常数。dk(h)=h(h+1)…(h+k-1)/k!当λ=1/2,f∈s时为I.V.Milm所证明。定理二 若f∈M并  相似文献   

2.
设D是C中的单位圆盘及为[0,1)上的正规函数。对于0<P<∞,这样的函数用于定义一个带权为 ̄p(|z|)/(1-|z| ̄2)的Bergman空间A ̄p.本文刻画了A ̄p中函数之零点集的结构.作为应用,又给出了A ̄p中函数序列插值的条件。  相似文献   

3.
涂振汉 《数学杂志》1995,15(1):72-76
设(A,(z))^ni=0为复平面上的整函数且没肥公共零点,令k+1是(Ai(z))^ni=0在复数域上的极大线性无关数,设W=W(z)由下列不可约方程An(z)W^n+An-1(z)W^n-1+...+A1(z)w+A0(z)=0所定义,我们称W=W(Z)为n值k型代数体函数(1≤K≤n)。  相似文献   

4.
关于面积平均p叶函数(Ⅱ)   总被引:1,自引:0,他引:1  
董新汉 《数学进展》1993,22(5):441-448
假设f(z)=z^p(1+Σ^∞n=1an^z^nk)是△={|z|<1}内面积平均p叶的(如果必要,△={|z|<1}\(-1,0])。本文的主要结论是:(1)如果设M(r)=max|f(z)|,则(1-r)2p/kM(r)→αk≤1(r→1),αk=1的充要条件是f(z)=z^p(1-xz^k)^-2p/k,|x|=1。进一步,如果1≤k<4p,我们有|an|n^1-2p/k→αkГ(2p/k  相似文献   

5.
1.引言 CG法对于变量个数很多的问题,是很有用的.1970年后它有了许多改进和发展,CCG法以正定圆锥函数为基础[1],它的一般方法是:设圆锥函数为 2]其中: V= V(x)=1+ aTx ≠ 0;, r ∈R1为常量; a,g ∈ Rn为常向量;x ∈ Rn为变向量;A∈Rn×n为对称正定矩阵.算法[1]:预先给出初始近似点x0∈ Rn及初始搜索方向 p0;满足:其中“I”是单位矩阵, V0= V(x0)= 1+ atx0及记号“”是函数的梯度.迭代格式为: xk+1= xk +λkpk,k= 0,1,2,…(3…  相似文献   

6.
关于Gross问题的一个注记   总被引:6,自引:0,他引:6  
本文研究亚纯函数的唯一性,得到了如下结果.设S={z:z3-z2-1=0},f(z)与g(z)是满足Θ(∞,f)>12,Θ(∞,g)>12,的两个非常数亚纯函数.若E(0,f)=E(0,g),E(S,f)=E(S,g)以及E(∞,f)=E(∞,g),则f(z)≡g(z).这个结果彻底解决了Gross[3]于1976年提出的一个问题  相似文献   

7.
本文研究了一类奇异非线性边界值问题g(x)g″(x)+h(x)=0,-k<x<1,g′(-k)=C,g(1)=0,k>0正解的存在性和非唯一性.问题起源于幂律流体理论中著名的边界层方程.  相似文献   

8.
王文昌  顾永兴 《数学杂志》1997,17(2):277-282
本文考虑了亚纯函数的幅角分布及其增长性的关系,得到了如下定理:设f(z)为亚纯函数,下级μ(μ〈+∞,argz=θk(k=1,2,…,q;0≤θ1〈θ2〈…〈θq〈2π,θq+1=θ1+2π)为q(1≤q〈+∞)条半直线使对A↓ε〉0有:limr→∞↑-log+n↑-(∪k=1↑qΩ↑-(θk+ε,θk+1-ε;r),f=x)/logr≤ρ〈+∞ x=0,∞则当存在一非负整数l使f^(l)(z)(  相似文献   

9.
证明了如下定理:设Φ(z)=∑nu=1∏ti=1faui0i…f(ki)iauiki∑mv=1∏ti=1fbvi0i…f(ki)ibviki其中fi(z),(1≤i≤t)是亚纯函数,auij,bvij为非负整数,则有T(r,Φ)≤∑ti=1{[Si+o(1)]m(r,fi)+[△i-ui+o(1)]N(r,fi)+(△i-Si)N(r,fi)}rE∈L.它是МОХОНЪКО的一个定理的精确改进.  相似文献   

10.
非光滑约束问题的既约次梯度法   总被引:1,自引:0,他引:1  
1引言 对带约束的不可微的非线性规划问题,由于不能使用梯度,求极小点就比较困难.本文给出解决此问题的一种有效的算法. 2 非光滑约束问题的既约次梯度法 1)非线性规划问题的Laerane对偶理论 考虑下面非线性规划问题其中g(x)=(g1(x),…,gr(x))T,h(x))=(h1(x),…,hm(x))T,f(x)=      Rn中是Lispschitz连续的i=1,2,…,r,j=1,2,…,m相应的Lagrange对偶问题为其中  (u, )=infL(x;u,v)=inf(f(x)+uT…  相似文献   

11.
In this paper, we study an optimal control problem for the mixed boundary value problem for an elastic body with quasistatic evolution of an internal damage variable. We suppose that the evolution of microscopic cracks and cavities responsible for the damage is described by a nonlinear parabolic equation. A density of surface traction p acting on a part of boundary of an elastic body Ω is taken as a boundary control. Because the initial boundary value problem of this type can exhibit the Lavrentieff phenomenon and non‐uniqueness of weak solutions, we deal with the solvability of this problem in the class of weak variational solutions. Using the convergence concept in variable spaces and following the direct method in calculus of variations, we prove the existence of optimal and approximate solutions to the optimal control problem under rather general assumptions on the quasistatic evolution of damage. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

12.
This work investigates the existence of globally Lipschitz continuous solutions to a class of initial-boundary value problem of quasilinear wave equations. Applying the Lax's method and generalized Glimm's method, we construct the approximate solutions of initial-boundary Riemann problem near the boundary layer and perturbed Riemann problem away from the boundary layer. By showing the weak convergence of residuals for the approximate solutions, we establish the global existence for the derivatives of solutions and obtain the existence of global Lipschitz continuous solutions of the problem.  相似文献   

13.
In this paper, we study the boundary layer problem for the incompressible MHD system with the magnetic field having a non-characteristic perfect conducting wall boundary condition. Using the multi-scale analysis and asymptotic expansion approach, we can construct the approximate solutions for the viscous and diffuse MHD system, and utilize the careful energy method to prove the validity of the approximate solutions.  相似文献   

14.
We propose a free boundary shallow water model for which we give an existence theorem. The proof uses an original Lagrangian discrete scheme in order to build a sequence of approximate solutions. The properties of this scheme allow to treat the difficulties linked to the boundary motion. These approximate solutions verify some compactness results which allow us to pass to the limit in the discrete problem.  相似文献   

15.
We study a coupled nonlinear boundary value problem which has been shown to have applications to fluid flow and heat transfer in a fluid film over a stretching surface for set values of the model parameters (one of which determines the size of the problem domain). For arbitrary values of these parameters we are able to establish the existence and uniqueness of a class of monotone solutions. Perturbation solutions are then constructed and used to approximate certain invariants for the solutions. We then study a related boundary value problem formed by imposing an additional boundary condition on one of the governing equations (which results in an ill-posed problem), and we arrive at conditions allowing for solutions to this four-parameter problem to agree with the solutions to the three-parameter problem.  相似文献   

16.
We consider two numerical methods for solving a periodic boundary value problem for a system of differential inclusions, the Galerkin method and the polygon method. To the original problem, we assign a sequence of its discretizations. Conditions under which the existence of solutions of the periodic boundary value problem implies the solvability of its discrete versions are presented. The convergence of the sequence of approximate solutions is analyzed.  相似文献   

17.
In this paper, we discuss the existence of weak solutions to the initial and boundary value problem of a class of nonlinear degenerate parabolic equations in non-divergence form. Applying the method of parabolic regularization, we prove the existence of weak solutions to the problem. By carefully analyzing the approximate solutions to the problem, we make a series of estimates to the solutions and prove the weak convergence of the approximation solution sequence. Finally we testify the existence of weak solutions to the problem.  相似文献   

18.
In this paper using the monotone iterative technique we establish the existence and uniqueness of positive solutions for a nonlinear discrete fractional boundary value problem with a $p$-Laplacian operator. Also we discuss an iterative sequence which yields the approximate solution for this problem.  相似文献   

19.
The aim of this paper is to explore the free boundary problem for the NonNewtonian shear thickening fluids. These fluids not only have vacuum, but also have strong nonlinear properties. In this paper, a class of approximate solutions is first constructed, and some uniform estimates are obtained for these approximate solutions. Finally, the existence of free boundary problem solutions is proved by these uniform estimates.  相似文献   

20.
In this paper we give existence and uniqueness theorems for weak solutions of a mixed initial and boundary value problem with conservative boundary conditions relating to a particular symmetric hyperbolic linear system with discontinuous coefficients. The unicity is proved also for a mixed non linear problem.  相似文献   

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