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1.
星形函数族的一个子族的极值点与支撑点   总被引:1,自引:0,他引:1  
彭志刚  杨爱芳 《数学杂志》1998,18(4):450-454
设F({n})={f(z):f(z)在|z|<1内解析,f(z)=z-∞n=1anzn,an≥0,+∞n=2nan≤1},则F({n})是星形函数族的一个子族.许多学者研究了这个函数族.设M={f(z):f(z)在|z|<1内解析,f(z)=z-∞n=1anzn,an≥an+1≥0,+∞n=2nan≤1}.在本文中我们找出了函数族M的极值点与支撑点.  相似文献   

2.
设有半参数回归模型yi=x’,β+f(ti)+ei,i=1,...n,其中{ti}为常数列,本文对{xi}为设计点列的情形,给出了β、f(t)有相合估计的条件;在{xi}为随机的情形,建立了f(t)估计的相合性。  相似文献   

3.
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   

4.
几类凝聚图的轮廓   总被引:1,自引:0,他引:1  
设G是个图,|V(G)=n|对G上的任一个标号f:V(G)→{1,…,n}记,且当j≠i时,G中有边以f(-1)(j)及f(-1)(i)为两端点}).称P(G)=min{P(f):f是G上的标号}为图G的轮廓.对以W表示G中W的边界.本文证明:i)若G是凝聚图,f及f是G上一对互逆标号,则P(G)=P(f)的充要条件是f为凝聚标号,且此时若G,H均是凝聚图,则存在阶梯标号。使得路、回、完全留之间的下列乘积图也是凝聚图,且其轮廓为  相似文献   

5.
罗宗俊 《数学杂志》1996,16(2):163-170
本文讨论了数学模型:max{f(x)│f(x)=min(1≤j≤n)〔c1jx1j+c2jx2j〕,x∈D},其中D={x│x={xij},nΣ(j=1)xij=a,i=1,2,xij≥0且为整数},并给出了一个拟多项式算法。  相似文献   

6.
一、选择题1.设集合M={x|22-x≥1},集合N={x|x2-2x-3<0},集合M∩N=()(A){x|0≤x<1}(B){x|0≤x<2}(C){x|0≤x≤1}(D){x|0≤x≤2}2.已知函数f(x)=2x,则函数y=|f-1(x-1...  相似文献   

7.
逆极限空间的伪轨跟踪性   总被引:1,自引:0,他引:1  
证明了对于由{Xi,i,fi}i=1生成的逆极限系统(X∞,f∞),如果每个fi具有伪轨跟踪性,则诱 导映射f∞也具有伪轨跟踪性.并构造了一个例子说明它的逆命题不成立.还证明了零维紧致度量群 的自同构拓扑共轭于一族有限型子转移生成的逆极限系统.  相似文献   

8.
新题征展(3)     
题组新编1.(1)设M={x|f(x)=0}、N={x|g(x)=0},则{x|f(x)·g(x)=0}为(  );(A)M (B)N (C)M∪N (D)以上都不对(2)设f(x)=x-1x+3,g(x)=x+3x-1,则集合{x|f(x)·g(x)=0}=  ;(3)设函数f(x)、g(x)的定义域依次是F、G,且M={x|f(x)=0}、N={x|g(x)=0},则{x|f(x)·g(x)=0}=  .2.(1)设m、k∈N,则Cnn+Cnn+1+Cnn+2+…+Cnn+k=  ;(2)求…  相似文献   

9.
齐型空间上的Lipschitz函数与Littlewood-Paley g-函数   总被引:3,自引:0,他引:3  
常心怡 《数学学报》1996,39(5):629-636
在θ阶正规齐型空间上,如果算子列{Sk}k∈Z是恒等逼近,Dk=Sk-Sk-1;本文给出一个用{Dk}k∈Z表达的f∈Lipα(Lipschitz函数类,0<α<θ)的充分必要条件.作为其推论得到,对于f∈LIpα,其Littlewood-Paleyg函数g(f)(X)或者处处为无穷大,或者在Lipα上有界.  相似文献   

10.
取定具下述性质的函数r(x)∈C∞(R):(i),τ(x)=τ(-x),(ii)0≤τ(x)≤1,(iii)τ(x)=1,当|x|≤1/2,(iv)τ(x)=0,当|x|≥1.单位序列{τn(x)},x∈Rm和n∈Im,定义作τm(x)=τ(x1/n1)…τ(xm/nm),n1,…,nm=1,2,….空间D’(Rm)中分布f和g的中性卷积fg定义作序列{fn*g}的极限,其中fn=f·τn.作者给出了一些新的卷积.  相似文献   

11.
As early as in 1990, Professor Sun Yongsheng, suggested his students at Beijing Normal University to consider research problems on the unit sphere. Under his guidance and encouragement his students started the research on spherical harmonic analysis and approximation. In this paper, we incompletely introduce the main achievements in this area obtained by our group and relative researchers during recent 5 years (2001-2005). The main topics are: convergence of Cesaro summability, a.e. and strong summability of Fourier-Laplace series; smoothness and K-functionals; Kolmogorov and linear widths.  相似文献   

12.
In this paper, we study the commutators generalized by multipliers and a BMO function. Under some assumptions, we establish its boundedness properties from certain atomic Hardy space Hb^p(R^n) into the Lebesgue space L^p with p 〈 1.  相似文献   

13.
In this paper we study best local quasi-rational approximation and best local approximation from finite dimensional subspaces of vectorial functions of several variables. Our approach extends and unifies several problems concerning best local multi-point approximation in different norms.  相似文献   

14.
<正>May 26,2014,Beijing Science is a human enterprise in the pursuit of knowledge.The scientific revolution that occurred in the 17th Century initiated the advances of modern science.The scientific knowledge system created by  相似文献   

15.
16.
<正>August 10-14,2015Beijing,ChinaThe International Congress on Industrial and Applied Mathematics(ICIAM)is the premier international congress in the field of applied mathematics held every four years under the auspices of the International Council for Industrial and Applied Mathematics.From August 10 to 14,2015,mathematicians,scientists  相似文献   

17.
Let P(z)=∑↓j=0↑n ajx^j be a polynomial of degree n. In this paper we prove a more general result which interalia improves upon the bounds of a class of polynomials. We also prove a result which includes some extensions and generalizations of Enestrǒm-Kakeya theorem.  相似文献   

18.
Shanzhen  Lu  Lifang  Xu 《分析论及其应用》2004,20(3):215-230
In this paper, the authors study the boundedness of the operator [μΩ, b], the commutator generated by a function b ∈ Lipβ(Rn)(0 <β≤ 1) and the Marcinkiewicz integrals μΩ, on the classical Hardy spaces and the Herz-type Hardy spaces in the case Ω∈ Lipα(Sn-1)(0 <α≤ 1).  相似文献   

19.
In applications it is useful to compute the local average empirical statistics on u. A very simple relation exists when of a function f(u) of an input u from the local averages are given by a Haar approximation. The question is to know if it holds for higher order approximation methods. To do so, it is necessary to use approximate product operators defined over linear approximation spaces. These products are characterized by a Strang and Fix like condition. An explicit construction of these product operators is exhibited for piecewise polynomial functions, using Hermite interpolation. The averaging relation which holds for the Haar approximation is then recovered when the product is defined by a two point Hermite interpolation.  相似文献   

20.
Given the Laplace transform F(s) of a function f(t), we develop a new algorithm to find an approximation to f(t) by the use of the classical Jacobi polynomials. The main contribution of our work is the development of a new and very effective method to determine the coefficients in the finite series expansion that approximation f(t) in terms of Jacobi polynomials. Some numerical examples are illustrated.  相似文献   

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