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1.
Qiming  Yan  朱磊 《数学学报》2008,51(5):900-910
讨论三维光滑复射影簇X上全纯曲线f:C→X的退化性.设D_1…,D_r为X上处于一般位置的相异的不可约有效除子.假定D_1…,D_r均为nef除子,而且存在正整数n_1…,n_r,c,使得n_in_jn_k(D_i.D_j.D_k)=c对所有i,j,k均成立.如果f的像取不到D_1…,D_r上的点,那么只要r≥11,f必定代数退化,即它的像包含于X的某个代数真子集中.  相似文献   

2.
Suppose that is a system of continuous subharmonic functions in the unit disk and is the class of holomorphic functions f in such that log|f(z)| ≤ B f p f (z) + C f , z ∈ , where B f and C f are constants and p f ∈ . We obtain sufficient conditions for a given number sequence Λ = { λn} ⊂ to be a subsequence of zeros of some nonzero holomorphic function from , i.e., Λ is a nonuniqueness sequence for .__________Translated from Matematicheskie Zametki, vol. 77, no. 5, 2005, pp. 775–787.Original Russian Text Copyright ©2005 by L. Yu. Cherednikova.  相似文献   

3.
阿美如 《数学季刊》2001,16(2):1-12
本文研究与其导数具有一个分担值对的整函数的唯一性问题,文中结果推广并改进了Jank Mues和Volkmann等人的一个结果以及杨连忠的R.Bruck的一个结果。  相似文献   

4.
一类非端点插值B样条曲线降阶的方法   总被引:1,自引:0,他引:1  
降阶算法是B样条曲线和曲面设计的一个基本算法,它广泛应用于组合曲线,蒙皮或扫描曲面等设计中.Piegl与Tiller曾给出B样条曲线的降阶方法.本文给出了解决更一般的非端点插值B样条曲线降阶的方法.新的方法主要是通过对现有的节点插入方法进行分析,给出了一种端点插值递推公式,并利用此公式对Piegl与Tiller降阶方法加以改进,使之能够解决非端点插值均匀及非均匀B样条曲线的降阶问题.  相似文献   

5.
亚纯函数理论的一个基本不等式及其应用   总被引:9,自引:0,他引:9  
王建平  仪洪勋 《数学学报》2006,49(2):443-450
本文首先证明了关于亚纯函数理论的一个基本不等式,进而用此不等式研究了与Hayman的一个结果密切相关的一类亚纯函数的值分布问题,得到如下结果:如果 f是一个超越亚纯函数,其所有零点的重数至少为k,则函数ff(k)取每一个有穷非零复数无穷多次,至多除去三个可能的例外正整数k=2,3,4.  相似文献   

6.
Bézier曲线降多阶逼近的一种方法   总被引:4,自引:0,他引:4  
文献[1,2]讨论了Bezier曲线一次降多阶逼近问题,得到了很好的结果.文献[1]利用广义逆矩阵得到不保端点插值的降多阶逼近曲线的控制顶点的表达式.但却没有得到带端点任意阶插值条件的降多阶逼近曲线的控制顶点的表达式.文献[2]得到了带端点任意阶插值的降多阶逼近曲线的控制顶点的解析表达式.本文首先给出两Bezier曲线间距离的定义;然后根据降阶曲线与原曲线间的距离最小,分别得到了用矩阵表示的不保端点插值和保端点任意阶插值的降多阶逼近曲线的控制顶点的显示表达式.所给数值例子显示,用本文方法得到的降多阶逼近曲线对原曲线有很好的逼近效果.  相似文献   

7.
本文对某类广义Hartogs三角形上的逆紧全纯自映射证明了刚性定理,即逆紧全纯自映射必定为全纯自同构.同时完全刻画了其全纯自同构群,并且给出了关于其全纯自同构以及两个这类域之间逆紧全纯映射的分类。  相似文献   

8.
Criteria are given for a mapping to have bounded distortion in terms of an integral estimate of the multiplicity function without any a priori assumption on the differential properties of the mapping. The result is most lucid and final in a sense for complex functions f:CC of one complex variable. Generalizations to multidimensional Beltrami systems are suggested.  相似文献   

9.
TheBergmanKernelFunctionandFullGroupofHolomorphicAutomorphismonaReinhardtDomainGuanBinxin(管冰辛)WangAn(王安)(Dept.ofMath.,Capital...  相似文献   

10.
Let X be a complex projective algebraic manifold of dimension 2 and let D1,…,Du be distinct irreducible divisors on X such that no three of them share a common point. Let f: C→X\(U1≤i≤uDi) be a holomorphic map. Assume that u≥4 and that there exist positive integers n1,…,nu, c such that ninj(Di.Dj) = c for all pairs i, j. Then f is algebraically degenerate, i.e. its image is contained in an algebraic curve on X.  相似文献   

11.
《Mathematische Nachrichten》2017,290(16):2560-2566
In this paper, we describe a second main theorem of holomorphic curves in , of hyper‐order strictly less than 1, that involves a general linear operator . As an application, we derive a truncated second main theorem of degenerate holomorphic curves of hyper‐order strictly less than 1 using Nochka weights.  相似文献   

12.
本文讨论P2(C)中全纯曲线相交处于次一般位置超平面的唯一性.设f1, f2, · · · , fλ为P2(C)中线性非退化的全纯曲线,H1, H1, · · · , Hq为P2(C)上处于m-次一般位置的超平面,满足Aj :f1-1(Hj) = · · · =fλ-1(Hj) (1 ≤ j ≤ q)且Ai ∩ Aj = ?(i = j).假设存在整数l (2 ≤ l ≤ λ),使得fj1(z) ∧ fj2(z) ∧ · · · ∧ fjl(z) = 0 (z ∈ Aj)对任意l个指标1 ≤ j1 < j2 < · · · < jl < λ成立.那么当 q > 2λ/λ-l+1 + 3/2 m时, f1 ∧ · · · ∧ fλ ≡ 0.关键技术是第二基本定理中不等式改进为: ∥(q - 3m/2)Tft(r)≤ Pjq=1N2(ft,Hj )(r, 0) + o(Tft(r))(1 ≤ t ≤ λ).  相似文献   

13.
Let D be a bounded strongly convex domain and let f be a holomorphicself-map of D. In this paper we introduce and study the dilatation(f) of f defined, if f has no fixed points in D, as the usualboundary dilatation coefficient of f at its Wolff point, or,if f has some fixed points in D, as the ratio of shrinking ofthe Kobayashi balls around a fixed point of f. In particular,we show that the map , defined as : f (f) [0,1], is lowersemicontinuous. Among other things, this allows us to studythe limits of a family of holomorphic self-maps of D. In thecase of an inner fixed point, the dilatation is an intrinsicmeasure of the order of contact of f(D) to D. Finally, using complex geodesics, we define and study a directionaldilatation, which is a measure of the shrinking of the domainalong a given direction. Again, results of semicontinuity aregiven and applied to a family of holomorphic self-maps. 2000Mathematical Subject Classification: primary 32H99; secondary30F99, 32H15.  相似文献   

14.
For problems in the calculus of variations with isoperimetric side constraints, we provide in this paper a set of points whose emptiness, independently of nonsingularity assumptions, is equivalent to the nonnegativity of the second variation along admissible variations. The main objective of introducing a characterization of this condition should be, of course, to obtain a simpler way of verifying it. There are two other sets of points available in the literature, introduced by Loewen and Zheng (1994) and Zeidan (1996), for which this necessary condition implies their emptiness. However, we show that verifying membership of these sets may be more difficult than checking directly if that condition holds. Contrary to this behavior, we prove that the desired objective of characterizing that condition is achieved by means of the set introduced in this paper.  相似文献   

15.
连杆机构曲线特征参数模糊相似度的判别方法   总被引:2,自引:0,他引:2  
通过快速傅立叶变换获取预定轨迹及已知连杆曲线的特征参数,使得轨迹曲线之间的比较转化为特征参数的模糊相似度判别。根据特征参数可进一步获取连杆曲线的数学表达式,从而为连杆机构运动分析提供理论依据。  相似文献   

16.
This paper is a subsequent work of [Invent. Math., 2013, 191: 197-253]. The second fundamental theorem in Ahlfors covering surface theory is that, for each set Eq of q (≥3) distinct points in the extended complex plane ; there is a minimal positive constant H0 (Eq) (called Ahlfors constant with respect to Eq), such that the inequality(q2)A()4π(f1(Eq)U)H0(Eq)L()holds for any simply-connected surface=f,U ; where A() is the area of; L() is the perimeter of; and # denotes the cardinality. It is difficult to compute H0 (Eq) explicitly for general set Eq; and only a few properties of H0(Eq) are known. The goals of this paper are to prove the continuity and differentiability of H0 (Eq); to estimate H0 (Eq); and to discuss the minimum of H0 (Eq) for fiixed q.  相似文献   

17.
In this paper, we discuss the influence of multiple values and Valiron deficiencies on the uniqueness problem of algebroid functions on annuli, we get the several uniqueness theorems of algebroid functions on annuli, and also we extend the Nevanlinna value distribution theory for algebroid functions on annuli.  相似文献   

18.
In this paper we propose two methods for approximating the distribution of the maximum for a chain-dependent process. For these methods we investigate the rate of convergence of the approximations. A simulation study was performed that demonstrated excellent performance of the approximations even for small sample sizes. In addition, an application was made to river flow data collected on the North Pacolet River in South Carolina.  相似文献   

19.
We introduce the notion of covering sequence of a Boolean function, related to the derivatives of the function. We give complete characterizations of balancedness, correlation immunity and resiliency of Boolean functions by means of their covering sequences. By considering particular covering sequences, we define subclasses of (correlation-immune) resilient functions. We derive upper bounds on their algebraic degrees and on their nonlinearities. We give constructions of resilient functions belonging to these classes. We show that they achieve the best known trade-off between order of resiliency, nonlinearity and algebraic degree.  相似文献   

20.
Let φ: 𝔻 → 𝔻 and ψ: 𝔻 → ? be analytic maps. They induce a weighted composition operator ψ C φ acting between weighted Bloch type spaces and weighted Banach spaces of holomorphic functions. Under some assumptions on the weights, we give a necessary as well as a sufficient condition when such an operator is bounded resp. compact.  相似文献   

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